1\input texinfo @c -*- texinfo -*- 2@documentencoding UTF-8 3 4@settitle Libswresample Documentation 5@titlepage 6@center @titlefont{Libswresample Documentation} 7@end titlepage 8 9@top 10 11@contents 12 13@chapter Description 14@c man begin DESCRIPTION 15 16The libswresample library performs highly optimized audio resampling, 17rematrixing and sample format conversion operations. 18 19Specifically, this library performs the following conversions: 20 21@itemize 22@item 23@emph{Resampling}: is the process of changing the audio rate, for 24example from a high sample rate of 44100Hz to 8000Hz. Audio 25conversion from high to low sample rate is a lossy process. Several 26resampling options and algorithms are available. 27 28@item 29@emph{Format conversion}: is the process of converting the type of 30samples, for example from 16-bit signed samples to unsigned 8-bit or 31float samples. It also handles packing conversion, when passing from 32packed layout (all samples belonging to distinct channels interleaved 33in the same buffer), to planar layout (all samples belonging to the 34same channel stored in a dedicated buffer or "plane"). 35 36@item 37@emph{Rematrixing}: is the process of changing the channel layout, for 38example from stereo to mono. When the input channels cannot be mapped 39to the output streams, the process is lossy, since it involves 40different gain factors and mixing. 41@end itemize 42 43Various other audio conversions (e.g. stretching and padding) are 44enabled through dedicated options. 45 46@c man end DESCRIPTION 47 48@chapter See Also 49 50@ifhtml 51@url{ffmpeg.html,ffmpeg}, @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, 52@url{ffmpeg-resampler.html,ffmpeg-resampler}, 53@url{libavutil.html,libavutil} 54@end ifhtml 55 56@ifnothtml 57ffmpeg(1), ffplay(1), ffprobe(1), 58ffmpeg-resampler(1), 59libavutil(3) 60@end ifnothtml 61 62@include authors.texi 63 64@ignore 65 66@setfilename libswresample 67@settitle audio resampling library 68 69@end ignore 70 71@bye 72