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1 \input texinfo @c -*- texinfo -*-
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2
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3 @settitle ffmpeg Documentation
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4 @titlepage
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5 @center @titlefont{ffmpeg Documentation}
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6 @end titlepage
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7
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8 @top
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9
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10 @contents
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11
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12 @chapter Synopsis
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13
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14 ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_file}@} ... @{[@var{output_file_options}] @file{output_file}@} ...
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15
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16 @chapter Description
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17 @c man begin DESCRIPTION
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18
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19 @command{ffmpeg} is a very fast video and audio converter that can also grab from
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20 a live audio/video source. It can also convert between arbitrary sample
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21 rates and resize video on the fly with a high quality polyphase filter.
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22
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23 @command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular
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24 files, pipes, network streams, grabbing devices, etc.), specified by the
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25 @code{-i} option, and writes to an arbitrary number of output "files", which are
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26 specified by a plain output filename. Anything found on the command line which
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27 cannot be interpreted as an option is considered to be an output filename.
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28
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29 Each input or output file can, in principle, contain any number of streams of
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30 different types (video/audio/subtitle/attachment/data). The allowed number and/or
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31 types of streams may be limited by the container format. Selecting which
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32 streams from which inputs will go into which output is either done automatically
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33 or with the @code{-map} option (see the Stream selection chapter).
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34
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35 To refer to input files in options, you must use their indices (0-based). E.g.
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36 the first input file is @code{0}, the second is @code{1}, etc. Similarly, streams
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37 within a file are referred to by their indices. E.g. @code{2:3} refers to the
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38 fourth stream in the third input file. Also see the Stream specifiers chapter.
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39
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40 As a general rule, options are applied to the next specified
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41 file. Therefore, order is important, and you can have the same
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42 option on the command line multiple times. Each occurrence is
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43 then applied to the next input or output file.
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44 Exceptions from this rule are the global options (e.g. verbosity level),
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45 which should be specified first.
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46
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47 Do not mix input and output files -- first specify all input files, then all
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48 output files. Also do not mix options which belong to different files. All
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49 options apply ONLY to the next input or output file and are reset between files.
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50
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51 @itemize
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52 @item
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53 To set the video bitrate of the output file to 64 kbit/s:
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54 @example
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55 ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
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56 @end example
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57
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58 @item
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59 To force the frame rate of the output file to 24 fps:
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60 @example
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61 ffmpeg -i input.avi -r 24 output.avi
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62 @end example
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63
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64 @item
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65 To force the frame rate of the input file (valid for raw formats only)
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66 to 1 fps and the frame rate of the output file to 24 fps:
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67 @example
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68 ffmpeg -r 1 -i input.m2v -r 24 output.avi
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69 @end example
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70 @end itemize
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71
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72 The format option may be needed for raw input files.
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73
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74 @c man end DESCRIPTION
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75
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76 @chapter Detailed description
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77 @c man begin DETAILED DESCRIPTION
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78
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79 The transcoding process in @command{ffmpeg} for each output can be described by
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80 the following diagram:
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81
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82 @example
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83 _______ ______________ _________ ______________ ________
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84 | | | | | | | | | |
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85 | input | demuxer | encoded data | decoder | decoded | encoder | encoded data | muxer | output |
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86 | file | ---------> | packets | ---------> | frames | ---------> | packets | -------> | file |
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87 |_______| |______________| |_________| |______________| |________|
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88
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89 @end example
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90
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91 @command{ffmpeg} calls the libavformat library (containing demuxers) to read
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92 input files and get packets containing encoded data from them. When there are
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93 multiple input files, @command{ffmpeg} tries to keep them synchronized by
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94 tracking lowest timestamp on any active input stream.
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95
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96 Encoded packets are then passed to the decoder (unless streamcopy is selected
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97 for the stream, see further for a description). The decoder produces
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98 uncompressed frames (raw video/PCM audio/...) which can be processed further by
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99 filtering (see next section). After filtering, the frames are passed to the
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100 encoder, which encodes them and outputs encoded packets. Finally those are
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101 passed to the muxer, which writes the encoded packets to the output file.
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102
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103 @section Filtering
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104 Before encoding, @command{ffmpeg} can process raw audio and video frames using
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105 filters from the libavfilter library. Several chained filters form a filter
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106 graph. @command{ffmpeg} distinguishes between two types of filtergraphs:
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107 simple and complex.
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108
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109 @subsection Simple filtergraphs
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110 Simple filtergraphs are those that have exactly one input and output, both of
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111 the same type. In the above diagram they can be represented by simply inserting
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112 an additional step between decoding and encoding:
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113
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114 @example
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115 _________ __________ ______________
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116 | | | | | |
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117 | decoded | simple filtergraph | filtered | encoder | encoded data |
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118 | frames | -------------------> | frames | ---------> | packets |
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119 |_________| |__________| |______________|
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120
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121 @end example
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122
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123 Simple filtergraphs are configured with the per-stream @option{-filter} option
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124 (with @option{-vf} and @option{-af} aliases for video and audio respectively).
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125 A simple filtergraph for video can look for example like this:
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126
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127 @example
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128 _______ _____________ _______ _____ ________
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129 | | | | | | | | | |
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130 | input | ---> | deinterlace | ---> | scale | ---> | fps | ---> | output |
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131 |_______| |_____________| |_______| |_____| |________|
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132
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133 @end example
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134
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135 Note that some filters change frame properties but not frame contents. E.g. the
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136 @code{fps} filter in the example above changes number of frames, but does not
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137 touch the frame contents. Another example is the @code{setpts} filter, which
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138 only sets timestamps and otherwise passes the frames unchanged.
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139
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140 @subsection Complex filtergraphs
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141 Complex filtergraphs are those which cannot be described as simply a linear
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142 processing chain applied to one stream. This is the case, for example, when the graph has
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143 more than one input and/or output, or when output stream type is different from
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144 input. They can be represented with the following diagram:
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145
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146 @example
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147 _________
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148 | |
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149 | input 0 |\ __________
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150 |_________| \ | |
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151 \ _________ /| output 0 |
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152 \ | | / |__________|
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153 _________ \| complex | /
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154 | | | |/
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155 | input 1 |---->| filter |\
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156 |_________| | | \ __________
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157 /| graph | \ | |
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158 / | | \| output 1 |
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159 _________ / |_________| |__________|
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160 | | /
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161 | input 2 |/
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162 |_________|
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163
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164 @end example
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165
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166 Complex filtergraphs are configured with the @option{-filter_complex} option.
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167 Note that this option is global, since a complex filtergraph, by its nature,
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168 cannot be unambiguously associated with a single stream or file.
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169
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170 The @option{-lavfi} option is equivalent to @option{-filter_complex}.
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171
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172 A trivial example of a complex filtergraph is the @code{overlay} filter, which
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173 has two video inputs and one video output, containing one video overlaid on top
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174 of the other. Its audio counterpart is the @code{amix} filter.
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175
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176 @section Stream copy
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177 Stream copy is a mode selected by supplying the @code{copy} parameter to the
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178 @option{-codec} option. It makes @command{ffmpeg} omit the decoding and encoding
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179 step for the specified stream, so it does only demuxing and muxing. It is useful
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180 for changing the container format or modifying container-level metadata. The
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181 diagram above will, in this case, simplify to this:
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182
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183 @example
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184 _______ ______________ ________
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185 | | | | | |
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186 | input | demuxer | encoded data | muxer | output |
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187 | file | ---------> | packets | -------> | file |
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188 |_______| |______________| |________|
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189
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190 @end example
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191
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192 Since there is no decoding or encoding, it is very fast and there is no quality
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193 loss. However, it might not work in some cases because of many factors. Applying
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194 filters is obviously also impossible, since filters work on uncompressed data.
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195
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196 @c man end DETAILED DESCRIPTION
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197
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198 @chapter Stream selection
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199 @c man begin STREAM SELECTION
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200
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201 By default, @command{ffmpeg} includes only one stream of each type (video, audio, subtitle)
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202 present in the input files and adds them to each output file. It picks the
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203 "best" of each based upon the following criteria: for video, it is the stream
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204 with the highest resolution, for audio, it is the stream with the most channels, for
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205 subtitles, it is the first subtitle stream. In the case where several streams of
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206 the same type rate equally, the stream with the lowest index is chosen.
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207
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208 You can disable some of those defaults by using the @code{-vn/-an/-sn} options. For
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209 full manual control, use the @code{-map} option, which disables the defaults just
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210 described.
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211
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212 @c man end STREAM SELECTION
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213
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214 @chapter Options
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215 @c man begin OPTIONS
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216
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217 @include avtools-common-opts.texi
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218
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219 @section Main options
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220
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221 @table @option
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222
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223 @item -f @var{fmt} (@emph{input/output})
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224 Force input or output file format. The format is normally auto detected for input
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225 files and guessed from the file extension for output files, so this option is not
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226 needed in most cases.
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227
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228 @item -i @var{filename} (@emph{input})
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229 input file name
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230
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231 @item -y (@emph{global})
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232 Overwrite output files without asking.
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233
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234 @item -n (@emph{global})
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235 Do not overwrite output files, and exit immediately if a specified
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236 output file already exists.
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237
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238 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
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239 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
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240 Select an encoder (when used before an output file) or a decoder (when used
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241 before an input file) for one or more streams. @var{codec} is the name of a
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242 decoder/encoder or a special value @code{copy} (output only) to indicate that
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243 the stream is not to be re-encoded.
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244
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245 For example
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246 @example
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247 ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
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248 @end example
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249 encodes all video streams with libx264 and copies all audio streams.
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250
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251 For each stream, the last matching @code{c} option is applied, so
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252 @example
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253 ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
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254 @end example
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255 will copy all the streams except the second video, which will be encoded with
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256 libx264, and the 138th audio, which will be encoded with libvorbis.
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257
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258 @item -t @var{duration} (@emph{output})
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259 Stop writing the output after its duration reaches @var{duration}.
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260 @var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
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261
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262 -to and -t are mutually exclusive and -t has priority.
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263
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264 @item -to @var{position} (@emph{output})
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265 Stop writing the output at @var{position}.
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266 @var{position} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form.
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267
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268 -to and -t are mutually exclusive and -t has priority.
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269
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270 @item -fs @var{limit_size} (@emph{output})
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271 Set the file size limit, expressed in bytes.
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272
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273 @item -ss @var{position} (@emph{input/output})
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274 When used as an input option (before @code{-i}), seeks in this input file to
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275 @var{position}. When used as an output option (before an output filename),
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276 decodes but discards input until the timestamps reach @var{position}. This is
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277 slower, but more accurate.
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278
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279 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
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280
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281 @item -itsoffset @var{offset} (@emph{input})
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282 Set the input time offset in seconds.
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283 @code{[-]hh:mm:ss[.xxx]} syntax is also supported.
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284 The offset is added to the timestamps of the input files.
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285 Specifying a positive offset means that the corresponding
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286 streams are delayed by @var{offset} seconds.
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287
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288 @item -timestamp @var{time} (@emph{output})
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289 Set the recording timestamp in the container.
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290 The syntax for @var{time} is:
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291 @example
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292 now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...])|(HHMMSS[.m...]))[Z|z])
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293 @end example
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294 If the value is "now" it takes the current time.
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295 Time is local time unless 'Z' or 'z' is appended, in which case it is
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296 interpreted as UTC.
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297 If the year-month-day part is not specified it takes the current
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298 year-month-day.
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299
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300 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
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301 Set a metadata key/value pair.
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302
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303 An optional @var{metadata_specifier} may be given to set metadata
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304 on streams or chapters. See @code{-map_metadata} documentation for
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305 details.
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306
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307 This option overrides metadata set with @code{-map_metadata}. It is
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308 also possible to delete metadata by using an empty value.
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309
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310 For example, for setting the title in the output file:
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311 @example
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312 ffmpeg -i in.avi -metadata title="my title" out.flv
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313 @end example
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314
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315 To set the language of the first audio stream:
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316 @example
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317 ffmpeg -i INPUT -metadata:s:a:1 language=eng OUTPUT
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318 @end example
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319
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320 @item -target @var{type} (@emph{output})
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321 Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
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322 @code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
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323 @code{film-} to use the corresponding standard. All the format options
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324 (bitrate, codecs, buffer sizes) are then set automatically. You can just type:
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325
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326 @example
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327 ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
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328 @end example
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329
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330 Nevertheless you can specify additional options as long as you know
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331 they do not conflict with the standard, as in:
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332
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333 @example
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334 ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
|
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335 @end example
|
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336
|
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337 @item -dframes @var{number} (@emph{output})
|
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338 Set the number of data frames to record. This is an alias for @code{-frames:d}.
|
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|
339
|
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|
340 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
|
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341 Stop writing to the stream after @var{framecount} frames.
|
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342
|
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343 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
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344 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
|
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345 Use fixed quality scale (VBR). The meaning of @var{q} is
|
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|
346 codec-dependent.
|
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|
347
|
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348 @anchor{filter_option}
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|
349 @item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream})
|
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350 Create the filtergraph specified by @var{filtergraph} and use it to
|
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|
351 filter the stream.
|
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|
352
|
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|
353 @var{filtergraph} is a description of the filtergraph to apply to
|
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|
354 the stream, and must have a single input and a single output of the
|
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355 same type of the stream. In the filtergraph, the input is associated
|
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|
356 to the label @code{in}, and the output to the label @code{out}. See
|
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|
357 the ffmpeg-filters manual for more information about the filtergraph
|
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|
358 syntax.
|
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|
359
|
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|
360 See the @ref{filter_complex_option,,-filter_complex option} if you
|
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|
361 want to create filtergraphs with multiple inputs and/or outputs.
|
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|
362
|
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|
363 @item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream})
|
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|
364 This option is similar to @option{-filter}, the only difference is that its
|
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|
365 argument is the name of the file from which a filtergraph description is to be
|
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|
366 read.
|
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|
367
|
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|
368 @item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
|
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|
369 Specify the preset for matching stream(s).
|
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|
370
|
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371 @item -stats (@emph{global})
|
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|
372 Print encoding progress/statistics. It is on by default, to explicitly
|
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|
373 disable it you need to specify @code{-nostats}.
|
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|
374
|
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|
375 @item -progress @var{url} (@emph{global})
|
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|
376 Send program-friendly progress information to @var{url}.
|
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|
377
|
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|
378 Progress information is written approximately every second and at the end of
|
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|
379 the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
|
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|
380 consists of only alphanumeric characters. The last key of a sequence of
|
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|
381 progress information is always "progress".
|
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|
382
|
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|
383 @item -stdin
|
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|
384 Enable interaction on standard input. On by default unless standard input is
|
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|
385 used as an input. To explicitly disable interaction you need to specify
|
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|
386 @code{-nostdin}.
|
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|
387
|
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|
388 Disabling interaction on standard input is useful, for example, if
|
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|
389 ffmpeg is in the background process group. Roughly the same result can
|
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|
390 be achieved with @code{ffmpeg ... < /dev/null} but it requires a
|
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|
391 shell.
|
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|
392
|
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|
393 @item -debug_ts (@emph{global})
|
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|
394 Print timestamp information. It is off by default. This option is
|
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|
395 mostly useful for testing and debugging purposes, and the output
|
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|
396 format may change from one version to another, so it should not be
|
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|
397 employed by portable scripts.
|
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|
398
|
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|
399 See also the option @code{-fdebug ts}.
|
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|
400
|
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|
401 @item -attach @var{filename} (@emph{output})
|
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|
402 Add an attachment to the output file. This is supported by a few formats
|
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|
403 like Matroska for e.g. fonts used in rendering subtitles. Attachments
|
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|
404 are implemented as a specific type of stream, so this option will add
|
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|
405 a new stream to the file. It is then possible to use per-stream options
|
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|
406 on this stream in the usual way. Attachment streams created with this
|
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|
407 option will be created after all the other streams (i.e. those created
|
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|
408 with @code{-map} or automatic mappings).
|
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|
409
|
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|
410 Note that for Matroska you also have to set the mimetype metadata tag:
|
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|
411 @example
|
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|
412 ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
|
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|
413 @end example
|
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|
414 (assuming that the attachment stream will be third in the output file).
|
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|
415
|
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|
416 @item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
|
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|
417 Extract the matching attachment stream into a file named @var{filename}. If
|
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|
418 @var{filename} is empty, then the value of the @code{filename} metadata tag
|
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|
419 will be used.
|
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|
420
|
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|
421 E.g. to extract the first attachment to a file named 'out.ttf':
|
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|
422 @example
|
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|
423 ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
|
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|
424 @end example
|
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|
425 To extract all attachments to files determined by the @code{filename} tag:
|
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|
426 @example
|
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|
427 ffmpeg -dump_attachment:t "" -i INPUT
|
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|
428 @end example
|
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|
429
|
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|
430 Technical note -- attachments are implemented as codec extradata, so this
|
yading@10
|
431 option can actually be used to extract extradata from any stream, not just
|
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|
432 attachments.
|
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|
433
|
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|
434 @end table
|
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|
435
|
yading@10
|
436 @section Video Options
|
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|
437
|
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|
438 @table @option
|
yading@10
|
439 @item -vframes @var{number} (@emph{output})
|
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|
440 Set the number of video frames to record. This is an alias for @code{-frames:v}.
|
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|
441 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
|
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|
442 Set frame rate (Hz value, fraction or abbreviation).
|
yading@10
|
443
|
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|
444 As an input option, ignore any timestamps stored in the file and instead
|
yading@10
|
445 generate timestamps assuming constant frame rate @var{fps}.
|
yading@10
|
446
|
yading@10
|
447 As an output option, duplicate or drop input frames to achieve constant output
|
yading@10
|
448 frame rate @var{fps}.
|
yading@10
|
449
|
yading@10
|
450 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
|
yading@10
|
451 Set frame size.
|
yading@10
|
452
|
yading@10
|
453 As an input option, this is a shortcut for the @option{video_size} private
|
yading@10
|
454 option, recognized by some demuxers for which the frame size is either not
|
yading@10
|
455 stored in the file or is configurable -- e.g. raw video or video grabbers.
|
yading@10
|
456
|
yading@10
|
457 As an output option, this inserts the @code{scale} video filter to the
|
yading@10
|
458 @emph{end} of the corresponding filtergraph. Please use the @code{scale} filter
|
yading@10
|
459 directly to insert it at the beginning or some other place.
|
yading@10
|
460
|
yading@10
|
461 The format is @samp{wxh} (default - same as source).
|
yading@10
|
462
|
yading@10
|
463 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
|
yading@10
|
464 Set the video display aspect ratio specified by @var{aspect}.
|
yading@10
|
465
|
yading@10
|
466 @var{aspect} can be a floating point number string, or a string of the
|
yading@10
|
467 form @var{num}:@var{den}, where @var{num} and @var{den} are the
|
yading@10
|
468 numerator and denominator of the aspect ratio. For example "4:3",
|
yading@10
|
469 "16:9", "1.3333", and "1.7777" are valid argument values.
|
yading@10
|
470
|
yading@10
|
471 If used together with @option{-vcodec copy}, it will affect the aspect ratio
|
yading@10
|
472 stored at container level, but not the aspect ratio stored in encoded
|
yading@10
|
473 frames, if it exists.
|
yading@10
|
474
|
yading@10
|
475 @item -vn (@emph{output})
|
yading@10
|
476 Disable video recording.
|
yading@10
|
477
|
yading@10
|
478 @item -vcodec @var{codec} (@emph{output})
|
yading@10
|
479 Set the video codec. This is an alias for @code{-codec:v}.
|
yading@10
|
480
|
yading@10
|
481 @item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
|
yading@10
|
482 Select the pass number (1 or 2). It is used to do two-pass
|
yading@10
|
483 video encoding. The statistics of the video are recorded in the first
|
yading@10
|
484 pass into a log file (see also the option -passlogfile),
|
yading@10
|
485 and in the second pass that log file is used to generate the video
|
yading@10
|
486 at the exact requested bitrate.
|
yading@10
|
487 On pass 1, you may just deactivate audio and set output to null,
|
yading@10
|
488 examples for Windows and Unix:
|
yading@10
|
489 @example
|
yading@10
|
490 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
|
yading@10
|
491 ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
|
yading@10
|
492 @end example
|
yading@10
|
493
|
yading@10
|
494 @item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream})
|
yading@10
|
495 Set two-pass log file name prefix to @var{prefix}, the default file name
|
yading@10
|
496 prefix is ``ffmpeg2pass''. The complete file name will be
|
yading@10
|
497 @file{PREFIX-N.log}, where N is a number specific to the output
|
yading@10
|
498 stream
|
yading@10
|
499
|
yading@10
|
500 @item -vlang @var{code}
|
yading@10
|
501 Set the ISO 639 language code (3 letters) of the current video stream.
|
yading@10
|
502
|
yading@10
|
503 @item -vf @var{filtergraph} (@emph{output})
|
yading@10
|
504 Create the filtergraph specified by @var{filtergraph} and use it to
|
yading@10
|
505 filter the stream.
|
yading@10
|
506
|
yading@10
|
507 This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}.
|
yading@10
|
508 @end table
|
yading@10
|
509
|
yading@10
|
510 @section Advanced Video Options
|
yading@10
|
511
|
yading@10
|
512 @table @option
|
yading@10
|
513 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
|
yading@10
|
514 Set pixel format. Use @code{-pix_fmts} to show all the supported
|
yading@10
|
515 pixel formats.
|
yading@10
|
516 If the selected pixel format can not be selected, ffmpeg will print a
|
yading@10
|
517 warning and select the best pixel format supported by the encoder.
|
yading@10
|
518 If @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error
|
yading@10
|
519 if the requested pixel format can not be selected, and automatic conversions
|
yading@10
|
520 inside filtergraphs are disabled.
|
yading@10
|
521 If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format
|
yading@10
|
522 as the input (or graph output) and automatic conversions are disabled.
|
yading@10
|
523
|
yading@10
|
524 @item -sws_flags @var{flags} (@emph{input/output})
|
yading@10
|
525 Set SwScaler flags.
|
yading@10
|
526 @item -vdt @var{n}
|
yading@10
|
527 Discard threshold.
|
yading@10
|
528
|
yading@10
|
529 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
|
yading@10
|
530 Rate control override for specific intervals, formatted as "int,int,int"
|
yading@10
|
531 list separated with slashes. Two first values are the beginning and
|
yading@10
|
532 end frame numbers, last one is quantizer to use if positive, or quality
|
yading@10
|
533 factor if negative.
|
yading@10
|
534
|
yading@10
|
535 @item -deinterlace
|
yading@10
|
536 Deinterlace pictures.
|
yading@10
|
537 This option is deprecated since the deinterlacing is very low quality.
|
yading@10
|
538 Use the yadif filter with @code{-filter:v yadif}.
|
yading@10
|
539 @item -ilme
|
yading@10
|
540 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
|
yading@10
|
541 Use this option if your input file is interlaced and you want
|
yading@10
|
542 to keep the interlaced format for minimum losses.
|
yading@10
|
543 The alternative is to deinterlace the input stream with
|
yading@10
|
544 @option{-deinterlace}, but deinterlacing introduces losses.
|
yading@10
|
545 @item -psnr
|
yading@10
|
546 Calculate PSNR of compressed frames.
|
yading@10
|
547 @item -vstats
|
yading@10
|
548 Dump video coding statistics to @file{vstats_HHMMSS.log}.
|
yading@10
|
549 @item -vstats_file @var{file}
|
yading@10
|
550 Dump video coding statistics to @var{file}.
|
yading@10
|
551 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
|
yading@10
|
552 top=1/bottom=0/auto=-1 field first
|
yading@10
|
553 @item -dc @var{precision}
|
yading@10
|
554 Intra_dc_precision.
|
yading@10
|
555 @item -vtag @var{fourcc/tag} (@emph{output})
|
yading@10
|
556 Force video tag/fourcc. This is an alias for @code{-tag:v}.
|
yading@10
|
557 @item -qphist (@emph{global})
|
yading@10
|
558 Show QP histogram
|
yading@10
|
559 @item -vbsf @var{bitstream_filter}
|
yading@10
|
560 Deprecated see -bsf
|
yading@10
|
561
|
yading@10
|
562 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
|
yading@10
|
563 @item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream})
|
yading@10
|
564 Force key frames at the specified timestamps, more precisely at the first
|
yading@10
|
565 frames after each specified time.
|
yading@10
|
566
|
yading@10
|
567 If the argument is prefixed with @code{expr:}, the string @var{expr}
|
yading@10
|
568 is interpreted like an expression and is evaluated for each frame. A
|
yading@10
|
569 key frame is forced in case the evaluation is non-zero.
|
yading@10
|
570
|
yading@10
|
571 If one of the times is "@code{chapters}[@var{delta}]", it is expanded into
|
yading@10
|
572 the time of the beginning of all chapters in the file, shifted by
|
yading@10
|
573 @var{delta}, expressed as a time in seconds.
|
yading@10
|
574 This option can be useful to ensure that a seek point is present at a
|
yading@10
|
575 chapter mark or any other designated place in the output file.
|
yading@10
|
576
|
yading@10
|
577 For example, to insert a key frame at 5 minutes, plus key frames 0.1 second
|
yading@10
|
578 before the beginning of every chapter:
|
yading@10
|
579 @example
|
yading@10
|
580 -force_key_frames 0:05:00,chapters-0.1
|
yading@10
|
581 @end example
|
yading@10
|
582
|
yading@10
|
583 The expression in @var{expr} can contain the following constants:
|
yading@10
|
584 @table @option
|
yading@10
|
585 @item n
|
yading@10
|
586 the number of current processed frame, starting from 0
|
yading@10
|
587 @item n_forced
|
yading@10
|
588 the number of forced frames
|
yading@10
|
589 @item prev_forced_n
|
yading@10
|
590 the number of the previous forced frame, it is @code{NAN} when no
|
yading@10
|
591 keyframe was forced yet
|
yading@10
|
592 @item prev_forced_t
|
yading@10
|
593 the time of the previous forced frame, it is @code{NAN} when no
|
yading@10
|
594 keyframe was forced yet
|
yading@10
|
595 @item t
|
yading@10
|
596 the time of the current processed frame
|
yading@10
|
597 @end table
|
yading@10
|
598
|
yading@10
|
599 For example to force a key frame every 5 seconds, you can specify:
|
yading@10
|
600 @example
|
yading@10
|
601 -force_key_frames expr:gte(t,n_forced*5)
|
yading@10
|
602 @end example
|
yading@10
|
603
|
yading@10
|
604 To force a key frame 5 seconds after the time of the last forced one,
|
yading@10
|
605 starting from second 13:
|
yading@10
|
606 @example
|
yading@10
|
607 -force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
|
yading@10
|
608 @end example
|
yading@10
|
609
|
yading@10
|
610 Note that forcing too many keyframes is very harmful for the lookahead
|
yading@10
|
611 algorithms of certain encoders: using fixed-GOP options or similar
|
yading@10
|
612 would be more efficient.
|
yading@10
|
613
|
yading@10
|
614 @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
|
yading@10
|
615 When doing stream copy, copy also non-key frames found at the
|
yading@10
|
616 beginning.
|
yading@10
|
617 @end table
|
yading@10
|
618
|
yading@10
|
619 @section Audio Options
|
yading@10
|
620
|
yading@10
|
621 @table @option
|
yading@10
|
622 @item -aframes @var{number} (@emph{output})
|
yading@10
|
623 Set the number of audio frames to record. This is an alias for @code{-frames:a}.
|
yading@10
|
624 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
|
yading@10
|
625 Set the audio sampling frequency. For output streams it is set by
|
yading@10
|
626 default to the frequency of the corresponding input stream. For input
|
yading@10
|
627 streams this option only makes sense for audio grabbing devices and raw
|
yading@10
|
628 demuxers and is mapped to the corresponding demuxer options.
|
yading@10
|
629 @item -aq @var{q} (@emph{output})
|
yading@10
|
630 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
|
yading@10
|
631 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
|
yading@10
|
632 Set the number of audio channels. For output streams it is set by
|
yading@10
|
633 default to the number of input audio channels. For input streams
|
yading@10
|
634 this option only makes sense for audio grabbing devices and raw demuxers
|
yading@10
|
635 and is mapped to the corresponding demuxer options.
|
yading@10
|
636 @item -an (@emph{output})
|
yading@10
|
637 Disable audio recording.
|
yading@10
|
638 @item -acodec @var{codec} (@emph{input/output})
|
yading@10
|
639 Set the audio codec. This is an alias for @code{-codec:a}.
|
yading@10
|
640 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
|
yading@10
|
641 Set the audio sample format. Use @code{-sample_fmts} to get a list
|
yading@10
|
642 of supported sample formats.
|
yading@10
|
643
|
yading@10
|
644 @item -af @var{filtergraph} (@emph{output})
|
yading@10
|
645 Create the filtergraph specified by @var{filtergraph} and use it to
|
yading@10
|
646 filter the stream.
|
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|
647
|
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|
648 This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}.
|
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|
649 @end table
|
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|
650
|
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|
651 @section Advanced Audio options:
|
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|
652
|
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|
653 @table @option
|
yading@10
|
654 @item -atag @var{fourcc/tag} (@emph{output})
|
yading@10
|
655 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
|
yading@10
|
656 @item -absf @var{bitstream_filter}
|
yading@10
|
657 Deprecated, see -bsf
|
yading@10
|
658 @item -guess_layout_max @var{channels} (@emph{input,per-stream})
|
yading@10
|
659 If some input channel layout is not known, try to guess only if it
|
yading@10
|
660 corresponds to at most the specified number of channels. For example, 2
|
yading@10
|
661 tells to @command{ffmpeg} to recognize 1 channel as mono and 2 channels as
|
yading@10
|
662 stereo but not 6 channels as 5.1. The default is to always try to guess. Use
|
yading@10
|
663 0 to disable all guessing.
|
yading@10
|
664 @end table
|
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|
665
|
yading@10
|
666 @section Subtitle options:
|
yading@10
|
667
|
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|
668 @table @option
|
yading@10
|
669 @item -slang @var{code}
|
yading@10
|
670 Set the ISO 639 language code (3 letters) of the current subtitle stream.
|
yading@10
|
671 @item -scodec @var{codec} (@emph{input/output})
|
yading@10
|
672 Set the subtitle codec. This is an alias for @code{-codec:s}.
|
yading@10
|
673 @item -sn (@emph{output})
|
yading@10
|
674 Disable subtitle recording.
|
yading@10
|
675 @item -sbsf @var{bitstream_filter}
|
yading@10
|
676 Deprecated, see -bsf
|
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|
677 @end table
|
yading@10
|
678
|
yading@10
|
679 @section Advanced Subtitle options:
|
yading@10
|
680
|
yading@10
|
681 @table @option
|
yading@10
|
682
|
yading@10
|
683 @item -fix_sub_duration
|
yading@10
|
684 Fix subtitles durations. For each subtitle, wait for the next packet in the
|
yading@10
|
685 same stream and adjust the duration of the first to avoid overlap. This is
|
yading@10
|
686 necessary with some subtitles codecs, especially DVB subtitles, because the
|
yading@10
|
687 duration in the original packet is only a rough estimate and the end is
|
yading@10
|
688 actually marked by an empty subtitle frame. Failing to use this option when
|
yading@10
|
689 necessary can result in exaggerated durations or muxing failures due to
|
yading@10
|
690 non-monotonic timestamps.
|
yading@10
|
691
|
yading@10
|
692 Note that this option will delay the output of all data until the next
|
yading@10
|
693 subtitle packet is decoded: it may increase memory consumption and latency a
|
yading@10
|
694 lot.
|
yading@10
|
695
|
yading@10
|
696 @item -canvas_size @var{size}
|
yading@10
|
697 Set the size of the canvas used to render subtitles.
|
yading@10
|
698
|
yading@10
|
699 @end table
|
yading@10
|
700
|
yading@10
|
701 @section Advanced options
|
yading@10
|
702
|
yading@10
|
703 @table @option
|
yading@10
|
704 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output})
|
yading@10
|
705
|
yading@10
|
706 Designate one or more input streams as a source for the output file. Each input
|
yading@10
|
707 stream is identified by the input file index @var{input_file_id} and
|
yading@10
|
708 the input stream index @var{input_stream_id} within the input
|
yading@10
|
709 file. Both indices start at 0. If specified,
|
yading@10
|
710 @var{sync_file_id}:@var{stream_specifier} sets which input stream
|
yading@10
|
711 is used as a presentation sync reference.
|
yading@10
|
712
|
yading@10
|
713 The first @code{-map} option on the command line specifies the
|
yading@10
|
714 source for output stream 0, the second @code{-map} option specifies
|
yading@10
|
715 the source for output stream 1, etc.
|
yading@10
|
716
|
yading@10
|
717 A @code{-} character before the stream identifier creates a "negative" mapping.
|
yading@10
|
718 It disables matching streams from already created mappings.
|
yading@10
|
719
|
yading@10
|
720 An alternative @var{[linklabel]} form will map outputs from complex filter
|
yading@10
|
721 graphs (see the @option{-filter_complex} option) to the output file.
|
yading@10
|
722 @var{linklabel} must correspond to a defined output link label in the graph.
|
yading@10
|
723
|
yading@10
|
724 For example, to map ALL streams from the first input file to output
|
yading@10
|
725 @example
|
yading@10
|
726 ffmpeg -i INPUT -map 0 output
|
yading@10
|
727 @end example
|
yading@10
|
728
|
yading@10
|
729 For example, if you have two audio streams in the first input file,
|
yading@10
|
730 these streams are identified by "0:0" and "0:1". You can use
|
yading@10
|
731 @code{-map} to select which streams to place in an output file. For
|
yading@10
|
732 example:
|
yading@10
|
733 @example
|
yading@10
|
734 ffmpeg -i INPUT -map 0:1 out.wav
|
yading@10
|
735 @end example
|
yading@10
|
736 will map the input stream in @file{INPUT} identified by "0:1" to
|
yading@10
|
737 the (single) output stream in @file{out.wav}.
|
yading@10
|
738
|
yading@10
|
739 For example, to select the stream with index 2 from input file
|
yading@10
|
740 @file{a.mov} (specified by the identifier "0:2"), and stream with
|
yading@10
|
741 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
|
yading@10
|
742 and copy them to the output file @file{out.mov}:
|
yading@10
|
743 @example
|
yading@10
|
744 ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
|
yading@10
|
745 @end example
|
yading@10
|
746
|
yading@10
|
747 To select all video and the third audio stream from an input file:
|
yading@10
|
748 @example
|
yading@10
|
749 ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
|
yading@10
|
750 @end example
|
yading@10
|
751
|
yading@10
|
752 To map all the streams except the second audio, use negative mappings
|
yading@10
|
753 @example
|
yading@10
|
754 ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
|
yading@10
|
755 @end example
|
yading@10
|
756
|
yading@10
|
757 Note that using this option disables the default mappings for this output file.
|
yading@10
|
758
|
yading@10
|
759 @item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
|
yading@10
|
760 Map an audio channel from a given input to an output. If
|
yading@10
|
761 @var{output_file_id}.@var{stream_specifier} is not set, the audio channel will
|
yading@10
|
762 be mapped on all the audio streams.
|
yading@10
|
763
|
yading@10
|
764 Using "-1" instead of
|
yading@10
|
765 @var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
|
yading@10
|
766 channel.
|
yading@10
|
767
|
yading@10
|
768 For example, assuming @var{INPUT} is a stereo audio file, you can switch the
|
yading@10
|
769 two audio channels with the following command:
|
yading@10
|
770 @example
|
yading@10
|
771 ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
|
yading@10
|
772 @end example
|
yading@10
|
773
|
yading@10
|
774 If you want to mute the first channel and keep the second:
|
yading@10
|
775 @example
|
yading@10
|
776 ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
|
yading@10
|
777 @end example
|
yading@10
|
778
|
yading@10
|
779 The order of the "-map_channel" option specifies the order of the channels in
|
yading@10
|
780 the output stream. The output channel layout is guessed from the number of
|
yading@10
|
781 channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
|
yading@10
|
782 in combination of "-map_channel" makes the channel gain levels to be updated if
|
yading@10
|
783 input and output channel layouts don't match (for instance two "-map_channel"
|
yading@10
|
784 options and "-ac 6").
|
yading@10
|
785
|
yading@10
|
786 You can also extract each channel of an input to specific outputs; the following
|
yading@10
|
787 command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0)
|
yading@10
|
788 to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs:
|
yading@10
|
789 @example
|
yading@10
|
790 ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
|
yading@10
|
791 @end example
|
yading@10
|
792
|
yading@10
|
793 The following example splits the channels of a stereo input into two separate
|
yading@10
|
794 streams, which are put into the same output file:
|
yading@10
|
795 @example
|
yading@10
|
796 ffmpeg -i stereo.wav -map 0:0 -map 0:0 -map_channel 0.0.0:0.0 -map_channel 0.0.1:0.1 -y out.ogg
|
yading@10
|
797 @end example
|
yading@10
|
798
|
yading@10
|
799 Note that currently each output stream can only contain channels from a single
|
yading@10
|
800 input stream; you can't for example use "-map_channel" to pick multiple input
|
yading@10
|
801 audio channels contained in different streams (from the same or different files)
|
yading@10
|
802 and merge them into a single output stream. It is therefore not currently
|
yading@10
|
803 possible, for example, to turn two separate mono streams into a single stereo
|
yading@10
|
804 stream. However splitting a stereo stream into two single channel mono streams
|
yading@10
|
805 is possible.
|
yading@10
|
806
|
yading@10
|
807 If you need this feature, a possible workaround is to use the @emph{amerge}
|
yading@10
|
808 filter. For example, if you need to merge a media (here @file{input.mkv}) with 2
|
yading@10
|
809 mono audio streams into one single stereo channel audio stream (and keep the
|
yading@10
|
810 video stream), you can use the following command:
|
yading@10
|
811 @example
|
yading@10
|
812 ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
|
yading@10
|
813 @end example
|
yading@10
|
814
|
yading@10
|
815 @item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
|
yading@10
|
816 Set metadata information of the next output file from @var{infile}. Note that
|
yading@10
|
817 those are file indices (zero-based), not filenames.
|
yading@10
|
818 Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy.
|
yading@10
|
819 A metadata specifier can have the following forms:
|
yading@10
|
820 @table @option
|
yading@10
|
821 @item @var{g}
|
yading@10
|
822 global metadata, i.e. metadata that applies to the whole file
|
yading@10
|
823
|
yading@10
|
824 @item @var{s}[:@var{stream_spec}]
|
yading@10
|
825 per-stream metadata. @var{stream_spec} is a stream specifier as described
|
yading@10
|
826 in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first
|
yading@10
|
827 matching stream is copied from. In an output metadata specifier, all matching
|
yading@10
|
828 streams are copied to.
|
yading@10
|
829
|
yading@10
|
830 @item @var{c}:@var{chapter_index}
|
yading@10
|
831 per-chapter metadata. @var{chapter_index} is the zero-based chapter index.
|
yading@10
|
832
|
yading@10
|
833 @item @var{p}:@var{program_index}
|
yading@10
|
834 per-program metadata. @var{program_index} is the zero-based program index.
|
yading@10
|
835 @end table
|
yading@10
|
836 If metadata specifier is omitted, it defaults to global.
|
yading@10
|
837
|
yading@10
|
838 By default, global metadata is copied from the first input file,
|
yading@10
|
839 per-stream and per-chapter metadata is copied along with streams/chapters. These
|
yading@10
|
840 default mappings are disabled by creating any mapping of the relevant type. A negative
|
yading@10
|
841 file index can be used to create a dummy mapping that just disables automatic copying.
|
yading@10
|
842
|
yading@10
|
843 For example to copy metadata from the first stream of the input file to global metadata
|
yading@10
|
844 of the output file:
|
yading@10
|
845 @example
|
yading@10
|
846 ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
|
yading@10
|
847 @end example
|
yading@10
|
848
|
yading@10
|
849 To do the reverse, i.e. copy global metadata to all audio streams:
|
yading@10
|
850 @example
|
yading@10
|
851 ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
|
yading@10
|
852 @end example
|
yading@10
|
853 Note that simple @code{0} would work as well in this example, since global
|
yading@10
|
854 metadata is assumed by default.
|
yading@10
|
855
|
yading@10
|
856 @item -map_chapters @var{input_file_index} (@emph{output})
|
yading@10
|
857 Copy chapters from input file with index @var{input_file_index} to the next
|
yading@10
|
858 output file. If no chapter mapping is specified, then chapters are copied from
|
yading@10
|
859 the first input file with at least one chapter. Use a negative file index to
|
yading@10
|
860 disable any chapter copying.
|
yading@10
|
861
|
yading@10
|
862 @item -benchmark (@emph{global})
|
yading@10
|
863 Show benchmarking information at the end of an encode.
|
yading@10
|
864 Shows CPU time used and maximum memory consumption.
|
yading@10
|
865 Maximum memory consumption is not supported on all systems,
|
yading@10
|
866 it will usually display as 0 if not supported.
|
yading@10
|
867 @item -benchmark_all (@emph{global})
|
yading@10
|
868 Show benchmarking information during the encode.
|
yading@10
|
869 Shows CPU time used in various steps (audio/video encode/decode).
|
yading@10
|
870 @item -timelimit @var{duration} (@emph{global})
|
yading@10
|
871 Exit after ffmpeg has been running for @var{duration} seconds.
|
yading@10
|
872 @item -dump (@emph{global})
|
yading@10
|
873 Dump each input packet to stderr.
|
yading@10
|
874 @item -hex (@emph{global})
|
yading@10
|
875 When dumping packets, also dump the payload.
|
yading@10
|
876 @item -re (@emph{input})
|
yading@10
|
877 Read input at native frame rate. Mainly used to simulate a grab device.
|
yading@10
|
878 By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
|
yading@10
|
879 This option will slow down the reading of the input(s) to the native frame rate
|
yading@10
|
880 of the input(s). It is useful for real-time output (e.g. live streaming). If
|
yading@10
|
881 your input(s) is coming from some other live streaming source (through HTTP or
|
yading@10
|
882 UDP for example) the server might already be in real-time, thus the option will
|
yading@10
|
883 likely not be required. On the other hand, this is meaningful if your input(s)
|
yading@10
|
884 is a file you are trying to push in real-time.
|
yading@10
|
885 @item -loop_input
|
yading@10
|
886 Loop over the input stream. Currently it works only for image
|
yading@10
|
887 streams. This option is used for automatic FFserver testing.
|
yading@10
|
888 This option is deprecated, use -loop 1.
|
yading@10
|
889 @item -loop_output @var{number_of_times}
|
yading@10
|
890 Repeatedly loop output for formats that support looping such as animated GIF
|
yading@10
|
891 (0 will loop the output infinitely).
|
yading@10
|
892 This option is deprecated, use -loop.
|
yading@10
|
893 @item -vsync @var{parameter}
|
yading@10
|
894 Video sync method.
|
yading@10
|
895 For compatibility reasons old values can be specified as numbers.
|
yading@10
|
896 Newly added values will have to be specified as strings always.
|
yading@10
|
897
|
yading@10
|
898 @table @option
|
yading@10
|
899 @item 0, passthrough
|
yading@10
|
900 Each frame is passed with its timestamp from the demuxer to the muxer.
|
yading@10
|
901 @item 1, cfr
|
yading@10
|
902 Frames will be duplicated and dropped to achieve exactly the requested
|
yading@10
|
903 constant frame rate.
|
yading@10
|
904 @item 2, vfr
|
yading@10
|
905 Frames are passed through with their timestamp or dropped so as to
|
yading@10
|
906 prevent 2 frames from having the same timestamp.
|
yading@10
|
907 @item drop
|
yading@10
|
908 As passthrough but destroys all timestamps, making the muxer generate
|
yading@10
|
909 fresh timestamps based on frame-rate.
|
yading@10
|
910 @item -1, auto
|
yading@10
|
911 Chooses between 1 and 2 depending on muxer capabilities. This is the
|
yading@10
|
912 default method.
|
yading@10
|
913 @end table
|
yading@10
|
914
|
yading@10
|
915 Note that the timestamps may be further modified by the muxer, after this.
|
yading@10
|
916 For example, in the case that the format option @option{avoid_negative_ts}
|
yading@10
|
917 is enabled.
|
yading@10
|
918
|
yading@10
|
919 With -map you can select from which stream the timestamps should be
|
yading@10
|
920 taken. You can leave either video or audio unchanged and sync the
|
yading@10
|
921 remaining stream(s) to the unchanged one.
|
yading@10
|
922
|
yading@10
|
923 @item -async @var{samples_per_second}
|
yading@10
|
924 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
|
yading@10
|
925 the parameter is the maximum samples per second by which the audio is changed.
|
yading@10
|
926 -async 1 is a special case where only the start of the audio stream is corrected
|
yading@10
|
927 without any later correction.
|
yading@10
|
928
|
yading@10
|
929 Note that the timestamps may be further modified by the muxer, after this.
|
yading@10
|
930 For example, in the case that the format option @option{avoid_negative_ts}
|
yading@10
|
931 is enabled.
|
yading@10
|
932
|
yading@10
|
933 This option has been deprecated. Use the @code{aresample} audio filter instead.
|
yading@10
|
934
|
yading@10
|
935 @item -copyts
|
yading@10
|
936 Do not process input timestamps, but keep their values without trying
|
yading@10
|
937 to sanitize them. In particular, do not remove the initial start time
|
yading@10
|
938 offset value.
|
yading@10
|
939
|
yading@10
|
940 Note that, depending on the @option{vsync} option or on specific muxer
|
yading@10
|
941 processing (e.g. in case the format option @option{avoid_negative_ts}
|
yading@10
|
942 is enabled) the output timestamps may mismatch with the input
|
yading@10
|
943 timestamps even when this option is selected.
|
yading@10
|
944
|
yading@10
|
945 @item -copytb @var{mode}
|
yading@10
|
946 Specify how to set the encoder timebase when stream copying. @var{mode} is an
|
yading@10
|
947 integer numeric value, and can assume one of the following values:
|
yading@10
|
948
|
yading@10
|
949 @table @option
|
yading@10
|
950 @item 1
|
yading@10
|
951 Use the demuxer timebase.
|
yading@10
|
952
|
yading@10
|
953 The time base is copied to the output encoder from the corresponding input
|
yading@10
|
954 demuxer. This is sometimes required to avoid non monotonically increasing
|
yading@10
|
955 timestamps when copying video streams with variable frame rate.
|
yading@10
|
956
|
yading@10
|
957 @item 0
|
yading@10
|
958 Use the decoder timebase.
|
yading@10
|
959
|
yading@10
|
960 The time base is copied to the output encoder from the corresponding input
|
yading@10
|
961 decoder.
|
yading@10
|
962
|
yading@10
|
963 @item -1
|
yading@10
|
964 Try to make the choice automatically, in order to generate a sane output.
|
yading@10
|
965 @end table
|
yading@10
|
966
|
yading@10
|
967 Default value is -1.
|
yading@10
|
968
|
yading@10
|
969 @item -shortest (@emph{output})
|
yading@10
|
970 Finish encoding when the shortest input stream ends.
|
yading@10
|
971 @item -dts_delta_threshold
|
yading@10
|
972 Timestamp discontinuity delta threshold.
|
yading@10
|
973 @item -muxdelay @var{seconds} (@emph{input})
|
yading@10
|
974 Set the maximum demux-decode delay.
|
yading@10
|
975 @item -muxpreload @var{seconds} (@emph{input})
|
yading@10
|
976 Set the initial demux-decode delay.
|
yading@10
|
977 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
|
yading@10
|
978 Assign a new stream-id value to an output stream. This option should be
|
yading@10
|
979 specified prior to the output filename to which it applies.
|
yading@10
|
980 For the situation where multiple output files exist, a streamid
|
yading@10
|
981 may be reassigned to a different value.
|
yading@10
|
982
|
yading@10
|
983 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
|
yading@10
|
984 an output mpegts file:
|
yading@10
|
985 @example
|
yading@10
|
986 ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
|
yading@10
|
987 @end example
|
yading@10
|
988
|
yading@10
|
989 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
|
yading@10
|
990 Set bitstream filters for matching streams. @var{bitstream_filters} is
|
yading@10
|
991 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
|
yading@10
|
992 to get the list of bitstream filters.
|
yading@10
|
993 @example
|
yading@10
|
994 ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
|
yading@10
|
995 @end example
|
yading@10
|
996 @example
|
yading@10
|
997 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
|
yading@10
|
998 @end example
|
yading@10
|
999
|
yading@10
|
1000 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{per-stream})
|
yading@10
|
1001 Force a tag/fourcc for matching streams.
|
yading@10
|
1002
|
yading@10
|
1003 @item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff}
|
yading@10
|
1004 Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';'
|
yading@10
|
1005 (or '.') for drop.
|
yading@10
|
1006 @example
|
yading@10
|
1007 ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
|
yading@10
|
1008 @end example
|
yading@10
|
1009
|
yading@10
|
1010 @anchor{filter_complex_option}
|
yading@10
|
1011 @item -filter_complex @var{filtergraph} (@emph{global})
|
yading@10
|
1012 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
|
yading@10
|
1013 outputs. For simple graphs -- those with one input and one output of the same
|
yading@10
|
1014 type -- see the @option{-filter} options. @var{filtergraph} is a description of
|
yading@10
|
1015 the filtergraph, as described in the ``Filtergraph syntax'' section of the
|
yading@10
|
1016 ffmpeg-filters manual.
|
yading@10
|
1017
|
yading@10
|
1018 Input link labels must refer to input streams using the
|
yading@10
|
1019 @code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map}
|
yading@10
|
1020 uses). If @var{stream_specifier} matches multiple streams, the first one will be
|
yading@10
|
1021 used. An unlabeled input will be connected to the first unused input stream of
|
yading@10
|
1022 the matching type.
|
yading@10
|
1023
|
yading@10
|
1024 Output link labels are referred to with @option{-map}. Unlabeled outputs are
|
yading@10
|
1025 added to the first output file.
|
yading@10
|
1026
|
yading@10
|
1027 Note that with this option it is possible to use only lavfi sources without
|
yading@10
|
1028 normal input files.
|
yading@10
|
1029
|
yading@10
|
1030 For example, to overlay an image over video
|
yading@10
|
1031 @example
|
yading@10
|
1032 ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
|
yading@10
|
1033 '[out]' out.mkv
|
yading@10
|
1034 @end example
|
yading@10
|
1035 Here @code{[0:v]} refers to the first video stream in the first input file,
|
yading@10
|
1036 which is linked to the first (main) input of the overlay filter. Similarly the
|
yading@10
|
1037 first video stream in the second input is linked to the second (overlay) input
|
yading@10
|
1038 of overlay.
|
yading@10
|
1039
|
yading@10
|
1040 Assuming there is only one video stream in each input file, we can omit input
|
yading@10
|
1041 labels, so the above is equivalent to
|
yading@10
|
1042 @example
|
yading@10
|
1043 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
|
yading@10
|
1044 '[out]' out.mkv
|
yading@10
|
1045 @end example
|
yading@10
|
1046
|
yading@10
|
1047 Furthermore we can omit the output label and the single output from the filter
|
yading@10
|
1048 graph will be added to the output file automatically, so we can simply write
|
yading@10
|
1049 @example
|
yading@10
|
1050 ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
|
yading@10
|
1051 @end example
|
yading@10
|
1052
|
yading@10
|
1053 To generate 5 seconds of pure red video using lavfi @code{color} source:
|
yading@10
|
1054 @example
|
yading@10
|
1055 ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
|
yading@10
|
1056 @end example
|
yading@10
|
1057
|
yading@10
|
1058 @item -lavfi @var{filtergraph} (@emph{global})
|
yading@10
|
1059 Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or
|
yading@10
|
1060 outputs. Equivalent to @option{-filter_complex}.
|
yading@10
|
1061
|
yading@10
|
1062 @item -filter_complex_script @var{filename} (@emph{global})
|
yading@10
|
1063 This option is similar to @option{-filter_complex}, the only difference is that
|
yading@10
|
1064 its argument is the name of the file from which a complex filtergraph
|
yading@10
|
1065 description is to be read.
|
yading@10
|
1066
|
yading@10
|
1067 @end table
|
yading@10
|
1068
|
yading@10
|
1069 As a special exception, you can use a bitmap subtitle stream as input: it
|
yading@10
|
1070 will be converted into a video with the same size as the largest video in
|
yading@10
|
1071 the file, or 720x576 if no video is present. Note that this is an
|
yading@10
|
1072 experimental and temporary solution. It will be removed once libavfilter has
|
yading@10
|
1073 proper support for subtitles.
|
yading@10
|
1074
|
yading@10
|
1075 For example, to hardcode subtitles on top of a DVB-T recording stored in
|
yading@10
|
1076 MPEG-TS format, delaying the subtitles by 1 second:
|
yading@10
|
1077 @example
|
yading@10
|
1078 ffmpeg -i input.ts -filter_complex \
|
yading@10
|
1079 '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
|
yading@10
|
1080 -sn -map '#0x2dc' output.mkv
|
yading@10
|
1081 @end example
|
yading@10
|
1082 (0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
|
yading@10
|
1083 audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
|
yading@10
|
1084
|
yading@10
|
1085 @section Preset files
|
yading@10
|
1086 A preset file contains a sequence of @var{option}=@var{value} pairs,
|
yading@10
|
1087 one for each line, specifying a sequence of options which would be
|
yading@10
|
1088 awkward to specify on the command line. Lines starting with the hash
|
yading@10
|
1089 ('#') character are ignored and are used to provide comments. Check
|
yading@10
|
1090 the @file{presets} directory in the FFmpeg source tree for examples.
|
yading@10
|
1091
|
yading@10
|
1092 Preset files are specified with the @code{vpre}, @code{apre},
|
yading@10
|
1093 @code{spre}, and @code{fpre} options. The @code{fpre} option takes the
|
yading@10
|
1094 filename of the preset instead of a preset name as input and can be
|
yading@10
|
1095 used for any kind of codec. For the @code{vpre}, @code{apre}, and
|
yading@10
|
1096 @code{spre} options, the options specified in a preset file are
|
yading@10
|
1097 applied to the currently selected codec of the same type as the preset
|
yading@10
|
1098 option.
|
yading@10
|
1099
|
yading@10
|
1100 The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
|
yading@10
|
1101 preset options identifies the preset file to use according to the
|
yading@10
|
1102 following rules:
|
yading@10
|
1103
|
yading@10
|
1104 First ffmpeg searches for a file named @var{arg}.ffpreset in the
|
yading@10
|
1105 directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
|
yading@10
|
1106 the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
|
yading@10
|
1107 or in a @file{ffpresets} folder along the executable on win32,
|
yading@10
|
1108 in that order. For example, if the argument is @code{libvpx-1080p}, it will
|
yading@10
|
1109 search for the file @file{libvpx-1080p.ffpreset}.
|
yading@10
|
1110
|
yading@10
|
1111 If no such file is found, then ffmpeg will search for a file named
|
yading@10
|
1112 @var{codec_name}-@var{arg}.ffpreset in the above-mentioned
|
yading@10
|
1113 directories, where @var{codec_name} is the name of the codec to which
|
yading@10
|
1114 the preset file options will be applied. For example, if you select
|
yading@10
|
1115 the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
|
yading@10
|
1116 then it will search for the file @file{libvpx-1080p.ffpreset}.
|
yading@10
|
1117 @c man end OPTIONS
|
yading@10
|
1118
|
yading@10
|
1119 @chapter Tips
|
yading@10
|
1120 @c man begin TIPS
|
yading@10
|
1121
|
yading@10
|
1122 @itemize
|
yading@10
|
1123 @item
|
yading@10
|
1124 For streaming at very low bitrate application, use a low frame rate
|
yading@10
|
1125 and a small GOP size. This is especially true for RealVideo where
|
yading@10
|
1126 the Linux player does not seem to be very fast, so it can miss
|
yading@10
|
1127 frames. An example is:
|
yading@10
|
1128
|
yading@10
|
1129 @example
|
yading@10
|
1130 ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
|
yading@10
|
1131 @end example
|
yading@10
|
1132
|
yading@10
|
1133 @item
|
yading@10
|
1134 The parameter 'q' which is displayed while encoding is the current
|
yading@10
|
1135 quantizer. The value 1 indicates that a very good quality could
|
yading@10
|
1136 be achieved. The value 31 indicates the worst quality. If q=31 appears
|
yading@10
|
1137 too often, it means that the encoder cannot compress enough to meet
|
yading@10
|
1138 your bitrate. You must either increase the bitrate, decrease the
|
yading@10
|
1139 frame rate or decrease the frame size.
|
yading@10
|
1140
|
yading@10
|
1141 @item
|
yading@10
|
1142 If your computer is not fast enough, you can speed up the
|
yading@10
|
1143 compression at the expense of the compression ratio. You can use
|
yading@10
|
1144 '-me zero' to speed up motion estimation, and '-g 0' to disable
|
yading@10
|
1145 motion estimation completely (you have only I-frames, which means it
|
yading@10
|
1146 is about as good as JPEG compression).
|
yading@10
|
1147
|
yading@10
|
1148 @item
|
yading@10
|
1149 To have very low audio bitrates, reduce the sampling frequency
|
yading@10
|
1150 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
|
yading@10
|
1151
|
yading@10
|
1152 @item
|
yading@10
|
1153 To have a constant quality (but a variable bitrate), use the option
|
yading@10
|
1154 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
|
yading@10
|
1155 quality).
|
yading@10
|
1156
|
yading@10
|
1157 @end itemize
|
yading@10
|
1158 @c man end TIPS
|
yading@10
|
1159
|
yading@10
|
1160 @chapter Examples
|
yading@10
|
1161 @c man begin EXAMPLES
|
yading@10
|
1162
|
yading@10
|
1163 @section Preset files
|
yading@10
|
1164
|
yading@10
|
1165 A preset file contains a sequence of @var{option=value} pairs, one for
|
yading@10
|
1166 each line, specifying a sequence of options which can be specified also on
|
yading@10
|
1167 the command line. Lines starting with the hash ('#') character are ignored and
|
yading@10
|
1168 are used to provide comments. Empty lines are also ignored. Check the
|
yading@10
|
1169 @file{presets} directory in the FFmpeg source tree for examples.
|
yading@10
|
1170
|
yading@10
|
1171 Preset files are specified with the @code{pre} option, this option takes a
|
yading@10
|
1172 preset name as input. FFmpeg searches for a file named @var{preset_name}.avpreset in
|
yading@10
|
1173 the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
|
yading@10
|
1174 the data directory defined at configuration time (usually @file{$PREFIX/share/ffmpeg})
|
yading@10
|
1175 in that order. For example, if the argument is @code{libx264-max}, it will
|
yading@10
|
1176 search for the file @file{libx264-max.avpreset}.
|
yading@10
|
1177
|
yading@10
|
1178 @section Video and Audio grabbing
|
yading@10
|
1179
|
yading@10
|
1180 If you specify the input format and device then ffmpeg can grab video
|
yading@10
|
1181 and audio directly.
|
yading@10
|
1182
|
yading@10
|
1183 @example
|
yading@10
|
1184 ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
|
yading@10
|
1185 @end example
|
yading@10
|
1186
|
yading@10
|
1187 Or with an ALSA audio source (mono input, card id 1) instead of OSS:
|
yading@10
|
1188 @example
|
yading@10
|
1189 ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
|
yading@10
|
1190 @end example
|
yading@10
|
1191
|
yading@10
|
1192 Note that you must activate the right video source and channel before
|
yading@10
|
1193 launching ffmpeg with any TV viewer such as
|
yading@10
|
1194 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
|
yading@10
|
1195 have to set the audio recording levels correctly with a
|
yading@10
|
1196 standard mixer.
|
yading@10
|
1197
|
yading@10
|
1198 @section X11 grabbing
|
yading@10
|
1199
|
yading@10
|
1200 Grab the X11 display with ffmpeg via
|
yading@10
|
1201
|
yading@10
|
1202 @example
|
yading@10
|
1203 ffmpeg -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
|
yading@10
|
1204 @end example
|
yading@10
|
1205
|
yading@10
|
1206 0.0 is display.screen number of your X11 server, same as
|
yading@10
|
1207 the DISPLAY environment variable.
|
yading@10
|
1208
|
yading@10
|
1209 @example
|
yading@10
|
1210 ffmpeg -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
|
yading@10
|
1211 @end example
|
yading@10
|
1212
|
yading@10
|
1213 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
|
yading@10
|
1214 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
|
yading@10
|
1215
|
yading@10
|
1216 @section Video and Audio file format conversion
|
yading@10
|
1217
|
yading@10
|
1218 Any supported file format and protocol can serve as input to ffmpeg:
|
yading@10
|
1219
|
yading@10
|
1220 Examples:
|
yading@10
|
1221 @itemize
|
yading@10
|
1222 @item
|
yading@10
|
1223 You can use YUV files as input:
|
yading@10
|
1224
|
yading@10
|
1225 @example
|
yading@10
|
1226 ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
|
yading@10
|
1227 @end example
|
yading@10
|
1228
|
yading@10
|
1229 It will use the files:
|
yading@10
|
1230 @example
|
yading@10
|
1231 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
|
yading@10
|
1232 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
|
yading@10
|
1233 @end example
|
yading@10
|
1234
|
yading@10
|
1235 The Y files use twice the resolution of the U and V files. They are
|
yading@10
|
1236 raw files, without header. They can be generated by all decent video
|
yading@10
|
1237 decoders. You must specify the size of the image with the @option{-s} option
|
yading@10
|
1238 if ffmpeg cannot guess it.
|
yading@10
|
1239
|
yading@10
|
1240 @item
|
yading@10
|
1241 You can input from a raw YUV420P file:
|
yading@10
|
1242
|
yading@10
|
1243 @example
|
yading@10
|
1244 ffmpeg -i /tmp/test.yuv /tmp/out.avi
|
yading@10
|
1245 @end example
|
yading@10
|
1246
|
yading@10
|
1247 test.yuv is a file containing raw YUV planar data. Each frame is composed
|
yading@10
|
1248 of the Y plane followed by the U and V planes at half vertical and
|
yading@10
|
1249 horizontal resolution.
|
yading@10
|
1250
|
yading@10
|
1251 @item
|
yading@10
|
1252 You can output to a raw YUV420P file:
|
yading@10
|
1253
|
yading@10
|
1254 @example
|
yading@10
|
1255 ffmpeg -i mydivx.avi hugefile.yuv
|
yading@10
|
1256 @end example
|
yading@10
|
1257
|
yading@10
|
1258 @item
|
yading@10
|
1259 You can set several input files and output files:
|
yading@10
|
1260
|
yading@10
|
1261 @example
|
yading@10
|
1262 ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
|
yading@10
|
1263 @end example
|
yading@10
|
1264
|
yading@10
|
1265 Converts the audio file a.wav and the raw YUV video file a.yuv
|
yading@10
|
1266 to MPEG file a.mpg.
|
yading@10
|
1267
|
yading@10
|
1268 @item
|
yading@10
|
1269 You can also do audio and video conversions at the same time:
|
yading@10
|
1270
|
yading@10
|
1271 @example
|
yading@10
|
1272 ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
|
yading@10
|
1273 @end example
|
yading@10
|
1274
|
yading@10
|
1275 Converts a.wav to MPEG audio at 22050 Hz sample rate.
|
yading@10
|
1276
|
yading@10
|
1277 @item
|
yading@10
|
1278 You can encode to several formats at the same time and define a
|
yading@10
|
1279 mapping from input stream to output streams:
|
yading@10
|
1280
|
yading@10
|
1281 @example
|
yading@10
|
1282 ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
|
yading@10
|
1283 @end example
|
yading@10
|
1284
|
yading@10
|
1285 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
|
yading@10
|
1286 file:index' specifies which input stream is used for each output
|
yading@10
|
1287 stream, in the order of the definition of output streams.
|
yading@10
|
1288
|
yading@10
|
1289 @item
|
yading@10
|
1290 You can transcode decrypted VOBs:
|
yading@10
|
1291
|
yading@10
|
1292 @example
|
yading@10
|
1293 ffmpeg -i snatch_1.vob -f avi -c:v mpeg4 -b:v 800k -g 300 -bf 2 -c:a libmp3lame -b:a 128k snatch.avi
|
yading@10
|
1294 @end example
|
yading@10
|
1295
|
yading@10
|
1296 This is a typical DVD ripping example; the input is a VOB file, the
|
yading@10
|
1297 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
|
yading@10
|
1298 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
|
yading@10
|
1299 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
|
yading@10
|
1300 input video. Furthermore, the audio stream is MP3-encoded so you need
|
yading@10
|
1301 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
|
yading@10
|
1302 The mapping is particularly useful for DVD transcoding
|
yading@10
|
1303 to get the desired audio language.
|
yading@10
|
1304
|
yading@10
|
1305 NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
|
yading@10
|
1306
|
yading@10
|
1307 @item
|
yading@10
|
1308 You can extract images from a video, or create a video from many images:
|
yading@10
|
1309
|
yading@10
|
1310 For extracting images from a video:
|
yading@10
|
1311 @example
|
yading@10
|
1312 ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
|
yading@10
|
1313 @end example
|
yading@10
|
1314
|
yading@10
|
1315 This will extract one video frame per second from the video and will
|
yading@10
|
1316 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
|
yading@10
|
1317 etc. Images will be rescaled to fit the new WxH values.
|
yading@10
|
1318
|
yading@10
|
1319 If you want to extract just a limited number of frames, you can use the
|
yading@10
|
1320 above command in combination with the -vframes or -t option, or in
|
yading@10
|
1321 combination with -ss to start extracting from a certain point in time.
|
yading@10
|
1322
|
yading@10
|
1323 For creating a video from many images:
|
yading@10
|
1324 @example
|
yading@10
|
1325 ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
|
yading@10
|
1326 @end example
|
yading@10
|
1327
|
yading@10
|
1328 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
|
yading@10
|
1329 composed of three digits padded with zeroes to express the sequence
|
yading@10
|
1330 number. It is the same syntax supported by the C printf function, but
|
yading@10
|
1331 only formats accepting a normal integer are suitable.
|
yading@10
|
1332
|
yading@10
|
1333 When importing an image sequence, -i also supports expanding
|
yading@10
|
1334 shell-like wildcard patterns (globbing) internally, by selecting the
|
yading@10
|
1335 image2-specific @code{-pattern_type glob} option.
|
yading@10
|
1336
|
yading@10
|
1337 For example, for creating a video from filenames matching the glob pattern
|
yading@10
|
1338 @code{foo-*.jpeg}:
|
yading@10
|
1339 @example
|
yading@10
|
1340 ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
|
yading@10
|
1341 @end example
|
yading@10
|
1342
|
yading@10
|
1343 @item
|
yading@10
|
1344 You can put many streams of the same type in the output:
|
yading@10
|
1345
|
yading@10
|
1346 @example
|
yading@10
|
1347 ffmpeg -i test1.avi -i test2.avi -map 0:3 -map 0:2 -map 0:1 -map 0:0 -c copy test12.nut
|
yading@10
|
1348 @end example
|
yading@10
|
1349
|
yading@10
|
1350 The resulting output file @file{test12.avi} will contain first four streams from
|
yading@10
|
1351 the input file in reverse order.
|
yading@10
|
1352
|
yading@10
|
1353 @item
|
yading@10
|
1354 To force CBR video output:
|
yading@10
|
1355 @example
|
yading@10
|
1356 ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
|
yading@10
|
1357 @end example
|
yading@10
|
1358
|
yading@10
|
1359 @item
|
yading@10
|
1360 The four options lmin, lmax, mblmin and mblmax use 'lambda' units,
|
yading@10
|
1361 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
|
yading@10
|
1362 @example
|
yading@10
|
1363 ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
|
yading@10
|
1364 @end example
|
yading@10
|
1365
|
yading@10
|
1366 @end itemize
|
yading@10
|
1367 @c man end EXAMPLES
|
yading@10
|
1368
|
yading@10
|
1369 @ifset config-all
|
yading@10
|
1370 @include all-components.texi
|
yading@10
|
1371 @end ifset
|
yading@10
|
1372
|
yading@10
|
1373 @chapter See Also
|
yading@10
|
1374
|
yading@10
|
1375 @ifhtml
|
yading@10
|
1376 @ifset config-all
|
yading@10
|
1377 @url{ffmpeg.html,ffmpeg}
|
yading@10
|
1378 @end ifset
|
yading@10
|
1379 @ifset config-not-all
|
yading@10
|
1380 @url{ffmpeg-all.html,ffmpeg-all},
|
yading@10
|
1381 @end ifset
|
yading@10
|
1382 @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
|
yading@10
|
1383 @url{ffmpeg-utils.html,ffmpeg-utils},
|
yading@10
|
1384 @url{ffmpeg-scaler.html,ffmpeg-scaler},
|
yading@10
|
1385 @url{ffmpeg-resampler.html,ffmpeg-resampler},
|
yading@10
|
1386 @url{ffmpeg-codecs.html,ffmpeg-codecs},
|
yading@10
|
1387 @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters},
|
yading@10
|
1388 @url{ffmpeg-formats.html,ffmpeg-formats},
|
yading@10
|
1389 @url{ffmpeg-devices.html,ffmpeg-devices},
|
yading@10
|
1390 @url{ffmpeg-protocols.html,ffmpeg-protocols},
|
yading@10
|
1391 @url{ffmpeg-filters.html,ffmpeg-filters}
|
yading@10
|
1392 @end ifhtml
|
yading@10
|
1393
|
yading@10
|
1394 @ifnothtml
|
yading@10
|
1395 @ifset config-all
|
yading@10
|
1396 ffmpeg(1),
|
yading@10
|
1397 @end ifset
|
yading@10
|
1398 @ifset config-not-all
|
yading@10
|
1399 ffmpeg-all(1),
|
yading@10
|
1400 @end ifset
|
yading@10
|
1401 ffplay(1), ffprobe(1), ffserver(1),
|
yading@10
|
1402 ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1),
|
yading@10
|
1403 ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1),
|
yading@10
|
1404 ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
|
yading@10
|
1405 @end ifnothtml
|
yading@10
|
1406
|
yading@10
|
1407 @include authors.texi
|
yading@10
|
1408
|
yading@10
|
1409 @ignore
|
yading@10
|
1410
|
yading@10
|
1411 @setfilename ffmpeg
|
yading@10
|
1412 @settitle ffmpeg video converter
|
yading@10
|
1413
|
yading@10
|
1414 @end ignore
|
yading@10
|
1415
|
yading@10
|
1416 @bye
|