annotate ffmpeg/doc/libswresample.pod @ 13:844d341cf643 tip

Back up before ISMIR
author Yading Song <yading.song@eecs.qmul.ac.uk>
date Thu, 31 Oct 2013 13:17:06 +0000
parents 6840f77b83aa
children
rev   line source
yading@10 1 =head1 NAME
yading@10 2
yading@10 3 libswresample - audio resampling library
yading@10 4
yading@10 5 =head1 DESCRIPTION
yading@10 6
yading@10 7
yading@10 8 The libswresample library performs highly optimized audio resampling,
yading@10 9 rematrixing and sample format conversion operations.
yading@10 10
yading@10 11 Specifically, this library performs the following conversions:
yading@10 12
yading@10 13
yading@10 14 =over 4
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yading@10 16
yading@10 17 =item *
yading@10 18
yading@10 19 I<Resampling>: is the process of changing the audio rate, for
yading@10 20 example from an high sample rate of 44100Hz to 8000Hz. Audio
yading@10 21 conversion from high to low sample rate is a lossy process. Several
yading@10 22 resampling options and algorithms are available.
yading@10 23
yading@10 24
yading@10 25 =item *
yading@10 26
yading@10 27 I<Format conversion>: is the process of converting the type of
yading@10 28 samples, for example from 16-bit signed samples to unsigned 8-bit or
yading@10 29 float samples. It also handles packing conversion, when passing from
yading@10 30 packed layout (all samples belonging to distinct channels interleaved
yading@10 31 in the same buffer), to planar layout (all samples belonging to the
yading@10 32 same channel stored in a dedicated buffer or "plane").
yading@10 33
yading@10 34
yading@10 35 =item *
yading@10 36
yading@10 37 I<Rematrixing>: is the process of changing the channel layout, for
yading@10 38 example from stereo to mono. When the input channels cannot be mapped
yading@10 39 to the output streams, the process is lossy, since it involves
yading@10 40 different gain factors and mixing.
yading@10 41
yading@10 42 =back
yading@10 43
yading@10 44
yading@10 45 Various other audio conversions (e.g. stretching and padding) are
yading@10 46 enabled through dedicated options.
yading@10 47
yading@10 48
yading@10 49
yading@10 50 =head1 SEE ALSO
yading@10 51
yading@10 52
yading@10 53
yading@10 54 ffmpeg(1), ffplay(1), ffprobe(1), ffserver(1),
yading@10 55 ffmpeg-resampler(1),
yading@10 56 libavutil(3)
yading@10 57
yading@10 58
yading@10 59 =head1 AUTHORS
yading@10 60
yading@10 61
yading@10 62 The FFmpeg developers.
yading@10 63
yading@10 64 For details about the authorship, see the Git history of the project
yading@10 65 (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command
yading@10 66 B<git log> in the FFmpeg source directory, or browsing the
yading@10 67 online repository at E<lt>B<http://source.ffmpeg.org>E<gt>.
yading@10 68
yading@10 69 Maintainers for the specific components are listed in the file
yading@10 70 F<MAINTAINERS> in the source code tree.
yading@10 71
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yading@10 73