third_party_ffmpeg/doc/faq.texi

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\input texinfo @c -*- texinfo -*-
@settitle FFmpeg FAQ
@titlepage
@sp 7
@center @titlefont{FFmpeg FAQ}
@sp 3
@end titlepage
@chapter General Problems
@section ffserver doesn't not work.
ffmpeg development is now concentrated on the codec and format
handling. New developments broke ffserver, so don't expect it to work
correctly. It is planned to fix it ASAP.
@section I cannot read this file although this format seems to be suppored by ffmpeg.
Even if ffmpeg can read the file format, it may not support all its
codecs. Please consult the supported codec list in the ffmpeg
documentation.
@section I get audio/video synchro problems when grabbing.
Currently, the grabbing stuff does not handle synchronisation
correctly. You are free to correct it. It is planned to fix it ASAP.
@section How do I encode jpegs to another format ?
If the jpegs are named img1.jpg, img2.jpg, img3.jpg,..., use:
@example
ffmpeg -i img%d.jpg /tmp/a.mpg
@end example
@samp{%d} is replaced by the image number.
@file{img%03d.jpg} generates @file{img001.jpg}, @file{img002.jpg}, etc...
The same system is used for the other image formats.
@section FFmpeg does not support codec XXX. Can you include a Windows DLL loader to support it ?
No. FFmpeg only supports open source codecs. Windows DLLs are not
portable, bloated and often slow.
@section How can I read from the standard input or write to the standard output ?
Use @file{-} as filename.
@section Why Audio is not decoded in VOB files ?
AC3 decoding is optional as the codec is currently released under the
GPL. Enable it with @code{./configure --enable-a52}. Take care: by
enabling AC3, you automatically change the license of libavcodec from
LGPL to GPL.
@chapter Development
@section Are there examples of use of the FFmpeg libraries libavcodec and libavformat ?
Yes. Read the Developers Guide of the FFmpeg documentation.
@section Can you support my C compiler XXX ?
No. Only GCC is supported. GCC is ported on most systems available and I
don't see the need to pollute the source code with @code{#ifdef}s
related to the compiler.
@section I want to use ffmpeg or libavcodec under Windows. Can you support my proprietary C compiler XXX ?
No. Use @code{mingw-gcc} available at @url{http://www.mingw.org/} to
compile the code. It generates object files fully compatible with other
windows compilers.
@section Can you add automake, libtool or autoconf support ?
No. These tools are too blowted and they complicate the build. Moreover,
since only @samp{gcc} is supported they would add little advantages in
terms of portability.
@bye