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1 =head1 NAME
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2
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3 libswresample - audio resampling library
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4
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5 =head1 DESCRIPTION
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6
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7
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8 The libswresample library performs highly optimized audio resampling,
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9 rematrixing and sample format conversion operations.
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10
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11 Specifically, this library performs the following conversions:
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12
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13
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14 =over 4
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15
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16
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17 =item *
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18
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19 I<Resampling>: is the process of changing the audio rate, for
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20 example from an high sample rate of 44100Hz to 8000Hz. Audio
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21 conversion from high to low sample rate is a lossy process. Several
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22 resampling options and algorithms are available.
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23
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24
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25 =item *
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26
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27 I<Format conversion>: is the process of converting the type of
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28 samples, for example from 16-bit signed samples to unsigned 8-bit or
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29 float samples. It also handles packing conversion, when passing from
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30 packed layout (all samples belonging to distinct channels interleaved
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31 in the same buffer), to planar layout (all samples belonging to the
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32 same channel stored in a dedicated buffer or "plane").
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33
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34
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35 =item *
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36
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37 I<Rematrixing>: is the process of changing the channel layout, for
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38 example from stereo to mono. When the input channels cannot be mapped
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39 to the output streams, the process is lossy, since it involves
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40 different gain factors and mixing.
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41
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42 =back
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43
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44
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45 Various other audio conversions (e.g. stretching and padding) are
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46 enabled through dedicated options.
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47
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48
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49
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50 =head1 SEE ALSO
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51
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52
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53
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54 ffmpeg(1), ffplay(1), ffprobe(1), ffserver(1),
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55 ffmpeg-resampler(1),
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56 libavutil(3)
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57
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58
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59 =head1 AUTHORS
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60
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61
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62 The FFmpeg developers.
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63
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64 For details about the authorship, see the Git history of the project
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65 (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command
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66 B<git log> in the FFmpeg source directory, or browsing the
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67 online repository at E<lt>B<http://source.ffmpeg.org>E<gt>.
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68
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69 Maintainers for the specific components are listed in the file
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70 F<MAINTAINERS> in the source code tree.
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71
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72
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73
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