dxtory: Factorize the buffer loading

[ffmpeg] / doc / faq.texi

diff --git a/doc/faq.texi b/doc/faq.texi
index 1d854d5470cbc6c23e23f583e79aa99bed5b56c0..b400124f694152bb2509d1f158f707eb0e49762a 100644 (file)
--- a/doc/faq.texi
+++ b/doc/faq.texi
@@ -1,69 +1,33 @@
 \input texinfo @c -*- texinfo -*-
 
 \input texinfo @c -*- texinfo -*-
 

-@settitle FFmpeg FAQ
+@settitle Libav FAQ

 @titlepage
 @titlepage

-@sp 7
-@center @titlefont{FFmpeg FAQ}
-@sp 3
+@center @titlefont{Libav FAQ}

 @end titlepage
 
 @end titlepage
 

+@top

 
 

-@chapter General Questions
-
-@section When will the next FFmpeg version be released? / Why are FFmpeg releases so few and far between?
+@contents

 
 

-Like most open source projects FFmpeg suffers from a certain lack of
-manpower. For this reason the developers have to prioritize the work
-they do and putting out releases is not at the top of the list, fixing
-bugs and reviewing patches takes precedence. Please don't complain or
-request more timely and/or frequent releases unless you are willing to
-help out creating them.
-
-@section I have a problem with an old version of FFmpeg; where should I report it?
-Nowhere. Upgrade to the latest release or if there is no recent release upgrade
-to Subversion HEAD. You could also try to report it. Maybe you will get lucky and
-become the first person in history to get an answer different from "upgrade
-to Subversion HEAD".
+@chapter General Questions

 
 

-@section Why doesn't FFmpeg support feature [xyz]?
+@section Why doesn't Libav support feature [xyz]?

 
 

-Because no one has taken on that task yet. FFmpeg development is
+Because no one has taken on that task yet. Libav development is

 driven by the tasks that are important to the individual developers.
 If there is a feature that is important to you, the best way to get
 it implemented is to undertake the task yourself or sponsor a developer.
 
 driven by the tasks that are important to the individual developers.
 If there is a feature that is important to you, the best way to get
 it implemented is to undertake the task yourself or sponsor a developer.
 

-@section FFmpeg does not support codec XXX. Can you include a Windows DLL loader to support it?
+@section Libav does not support codec XXX. Can you include a Windows DLL loader to support it?

 
 No. Windows DLLs are not portable, bloated and often slow.
 
 No. Windows DLLs are not portable, bloated and often slow.

-Moreover FFmpeg strives to support all codecs natively.
+Moreover Libav strives to support all codecs natively.

 A DLL loader is not conducive to that goal.
 
 A DLL loader is not conducive to that goal.
 

-@section My bug report/mail to ffmpeg-devel/user has not received any replies.
-
-Likely reasons
-@itemize
-@item We are busy and haven't had time yet to read your report or
-investigate the issue.
-@item You didn't follow bugreports.html.
-@item You didn't use Subversion HEAD.
-@item You reported a segmentation fault without gdb output.
-@item You describe a problem but not how to reproduce it.
-@item It's unclear if you use ffmpeg as command line tool or use
-libav* from another application.
-@item You speak about a video having problems on playback but
-not what you use to play it.
-@item We have no faint clue what you are talking about besides
-that it is related to FFmpeg.
-@end itemize
-
-@section Is there a forum for FFmpeg? I do not like mailing lists.
-
-Yes, (@url{http://dir.gmane.org/gmane.comp.video.ffmpeg.user}).
-
-@section I cannot read this file although this format seems to be supported by ffmpeg.
+@section I cannot read this file although this format seems to be supported by avconv.

 
 

-Even if ffmpeg can read the container format, it may not support all its
-codecs. Please consult the supported codec list in the ffmpeg
+Even if avconv can read the container format, it may not support all its
+codecs. Please consult the supported codec list in the avconv

 documentation.
 
 @section Which codecs are supported by Windows?
 documentation.
 
 @section Which codecs are supported by Windows?


@@ -83,7 +47,7 @@ The following list of video codecs should work on most Windows systems:
 .asf only
 @item mpeg4
 Only if you have some MPEG-4 codec like ffdshow or Xvid installed.
 .asf only
 @item mpeg4
 Only if you have some MPEG-4 codec like ffdshow or Xvid installed.

-@item mpeg1
+@item mpeg1video

 .mpg only
 @end table
 Note, ASF files often have .wmv or .wma extensions in Windows. It should also
 .mpg only
 @end table
 Note, ASF files often have .wmv or .wma extensions in Windows. It should also


@@ -95,9 +59,9 @@ The following list of audio codecs should work on most Windows systems:
 @table @option
 @item adpcm_ima_wav
 @item adpcm_ms
 @table @option
 @item adpcm_ima_wav
 @item adpcm_ms

-@item pcm
+@item pcm_s16le

 always
 always

-@item mp3
+@item libmp3lame

 If some MP3 codec like LAME is installed.
 @end table
 
 If some MP3 codec like LAME is installed.
 @end table
 


@@ -109,14 +73,14 @@ If some MP3 codec like LAME is installed.
 This is a bug in gcc. Do not report it to us. Instead, please report it to
 the gcc developers. Note that we will not add workarounds for gcc bugs.
 
 This is a bug in gcc. Do not report it to us. Instead, please report it to
 the gcc developers. Note that we will not add workarounds for gcc bugs.
 

+Also note that (some of) the gcc developers believe this is not a bug or
+not a bug they should fix:
+@url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11203}.
+Then again, some of them do not know the difference between an undecidable
+problem and an NP-hard problem...

 
 @chapter Usage
 
 
 @chapter Usage
 

-@section ffmpeg does not work; what is wrong?
-
-Try a @code{make distclean} in the ffmpeg source directory before the build. If this does not help see
-(@url{http://ffmpeg.org/bugreports.html}).
-

 @section How do I encode single pictures into movies?
 
 First, rename your pictures to follow a numerical sequence.
 @section How do I encode single pictures into movies?
 
 First, rename your pictures to follow a numerical sequence.


@@ -124,21 +88,40 @@ For example, img1.jpg, img2.jpg, img3.jpg,...
 Then you may run:
 
 @example
 Then you may run:
 
 @example

-  ffmpeg -f image2 -i img%d.jpg /tmp/a.mpg
+  avconv -f image2 -i img%d.jpg /tmp/a.mpg

 @end example
 
 Notice that @samp{%d} is replaced by the image number.
 
 @file{img%03d.jpg} means the sequence @file{img001.jpg}, @file{img002.jpg}, etc...
 
 @end example
 
 Notice that @samp{%d} is replaced by the image number.
 
 @file{img%03d.jpg} means the sequence @file{img001.jpg}, @file{img002.jpg}, etc...
 

-The same logic is used for any image format that ffmpeg reads.
+If you have large number of pictures to rename, you can use the
+following command to ease the burden. The command, using the bourne
+shell syntax, symbolically links all files in the current directory
+that match @code{*jpg} to the @file{/tmp} directory in the sequence of
+@file{img001.jpg}, @file{img002.jpg} and so on.
+
+@example
+  x=1; for i in *jpg; do counter=$(printf %03d $x); ln -s "$i" /tmp/img"$counter".jpg; x=$(($x+1)); done
+@end example
+
+If you want to sequence them by oldest modified first, substitute
+@code{$(ls -r -t *jpg)} in place of @code{*jpg}.
+
+Then run:
+
+@example
+  avconv -f image2 -i /tmp/img%03d.jpg /tmp/a.mpg
+@end example
+
+The same logic is used for any image format that avconv reads.

 
 @section How do I encode movie to single pictures?
 
 Use:
 
 @example
 
 @section How do I encode movie to single pictures?
 
 Use:
 
 @example

-  ffmpeg -i movie.mpg movie%d.jpg
+  avconv -i movie.mpg movie%d.jpg

 @end example
 
 The @file{movie.mpg} used as input will be converted to
 @end example
 
 The @file{movie.mpg} used as input will be converted to


@@ -146,24 +129,19 @@ The @file{movie.mpg} used as input will be converted to
 
 Instead of relying on file format self-recognition, you may also use
 @table @option
 
 Instead of relying on file format self-recognition, you may also use
 @table @option

-@item -vcodec ppm
-@item -vcodec png
-@item -vcodec mjpeg
+@item -c:v ppm
+@item -c:v png
+@item -c:v mjpeg

 @end table
 to force the encoding.
 
 Applying that to the previous example:
 @example
 @end table
 to force the encoding.
 
 Applying that to the previous example:
 @example

-  ffmpeg -i movie.mpg -f image2 -vcodec mjpeg menu%d.jpg
+  avconv -i movie.mpg -f image2 -c:v mjpeg menu%d.jpg

 @end example
 
 Beware that there is no "jpeg" codec. Use "mjpeg" instead.
 
 @end example
 
 Beware that there is no "jpeg" codec. Use "mjpeg" instead.
 

-@section I get "Unsupported codec (id=86043) for input stream #0.1". What is the problem?
-
-This is the Qcelp codec, FFmpeg has no support for that codec currently.
-Try MEncoder/MPlayer, it might work.
-

 @section Why do I see a slight quality degradation with multithreaded MPEG* encoding?
 
 For multithreaded MPEG* encoding, the encoded slices must be independent,
 @section Why do I see a slight quality degradation with multithreaded MPEG* encoding?
 
 For multithreaded MPEG* encoding, the encoded slices must be independent,


@@ -174,27 +152,6 @@ quite logical that there is a small reduction of quality. This is not a bug.
 
 Use @file{-} as file name.
 
 
 Use @file{-} as file name.
 

-@section Why does FFmpeg not decode audio in VOB files?
-
-The audio is AC-3 (a.k.a. A/52). AC-3 decoding is an optional component in FFmpeg
-as the component that handles AC-3 decoding is currently released under the GPL.
-Enable AC-3 decoding with @code{./configure --enable-gpl}. Take care: By
-enabling AC-3, you automatically change the license of libavcodec from
-LGPL to GPL.
-
-@section Why does the chrominance data seem to be sampled at a different time from the luminance data on bt8x8 captures on Linux?
-
-This is a well-known bug in the bt8x8 driver. For 2.4.26 there is a patch at
-(@url{http://svn.mplayerhq.hu/michael/trunk/patches/bttv-420-2.4.26.patch?view=co}). This may also
-apply cleanly to other 2.4-series kernels.
-
-@section How do I avoid the ugly aliasing artifacts in bt8x8 captures on Linux?
-
-Pass 'combfilter=1 lumafilter=1' to the bttv driver. Note though that 'combfilter=1'
-will cause somewhat too strong filtering. A fix is to apply (@url{http://svn.mplayerhq.hu/michael/trunk/patches/bttv-comb-2.4.26.patch?view=co})
-or (@url{http://svn.mplayerhq.hu/michael/trunk/patches/bttv-comb-2.6.6.patch?view=co})
-and pass 'combfilter=2'.
-

 @section -f jpeg doesn't work.
 
 Try '-f image2 test%d.jpg'.
 @section -f jpeg doesn't work.
 
 Try '-f image2 test%d.jpg'.


@@ -202,86 +159,51 @@ Try '-f image2 test%d.jpg'.
 @section Why can I not change the framerate?
 
 Some codecs, like MPEG-1/2, only allow a small number of fixed framerates.
 @section Why can I not change the framerate?
 
 Some codecs, like MPEG-1/2, only allow a small number of fixed framerates.

-Choose a different codec with the -vcodec command line option.
+Choose a different codec with the -c:v command line option.

 
 

-@section How do I encode Xvid or DivX video with ffmpeg?
+@section How do I encode Xvid or DivX video with avconv?

 
 Both Xvid and DivX (version 4+) are implementations of the ISO MPEG-4
 standard (note that there are many other coding formats that use this
 
 Both Xvid and DivX (version 4+) are implementations of the ISO MPEG-4
 standard (note that there are many other coding formats that use this

-same standard). Thus, use '-vcodec mpeg4' to encode in these formats. The
+same standard). Thus, use '-c:v mpeg4' to encode in these formats. The

 default fourcc stored in an MPEG-4-coded file will be 'FMP4'. If you want
 a different fourcc, use the '-vtag' option. E.g., '-vtag xvid' will
 force the fourcc 'xvid' to be stored as the video fourcc rather than the
 default.
 
 default fourcc stored in an MPEG-4-coded file will be 'FMP4'. If you want
 a different fourcc, use the '-vtag' option. E.g., '-vtag xvid' will
 force the fourcc 'xvid' to be stored as the video fourcc rather than the
 default.
 

-@section How do I encode videos which play on the iPod?
-
-@table @option
-@item needed stuff
--acodec libfaac -vcodec mpeg4 width<=320 height<=240
-@item working stuff
-4mv, title
-@item non-working stuff
-B-frames
-@item example command line
-ffmpeg -i input -acodec libfaac -ab 128kb -vcodec mpeg4 -b 1200kb -mbd 2 -flags +4mv+trell -aic 2 -cmp 2 -subcmp 2 -s 320x180 -title X output.mp4
-@end table
-
-@section How do I encode videos which play on the PSP?
-
-@table @option
-@item needed stuff
--acodec libfaac -vcodec mpeg4 width*height<=76800 width%16=0 height%16=0 -ar 24000 -r 30000/1001 or 15000/1001 -f psp
-@item working stuff
-4mv, title
-@item non-working stuff
-B-frames
-@item example command line
-ffmpeg -i input -acodec libfaac -ab 128kb -vcodec mpeg4 -b 1200kb -ar 24000 -mbd 2 -flags +4mv+trell -aic 2 -cmp 2 -subcmp 2 -s 368x192 -r 30000/1001 -title X -f psp output.mp4
-@item needed stuff for H.264
--acodec libfaac -vcodec h264 width*height<=76800 width%16=0? height%16=0? -ar 48000 -coder 1 -r 30000/1001 or 15000/1001 -f psp
-@item working stuff for H.264
-title, loop filter
-@item non-working stuff for H.264
-CAVLC
-@item example command line
-ffmpeg -i input -acodec libfaac -ab 128kb -vcodec h264 -b 1200kb -ar 48000 -mbd 2 -coder 1 -cmp 2 -subcmp 2 -s 368x192 -r 30000/1001 -title X -f psp -flags loop -trellis 2 -partitions parti4x4+parti8x8+partp4x4+partp8x8+partb8x8 output.mp4
-@end table
-

 @section Which are good parameters for encoding high quality MPEG-4?
 
 @section Which are good parameters for encoding high quality MPEG-4?
 

-'-mbd rd -flags +4mv+trell+aic -cmp 2 -subcmp 2 -g 300 -pass 1/2',
+'-mbd rd -flags +mv4+aic -trellis 2 -cmp 2 -subcmp 2 -g 300 -pass 1/2',

 things to try: '-bf 2', '-flags qprd', '-flags mv0', '-flags skiprd'.
 
 @section Which are good parameters for encoding high quality MPEG-1/MPEG-2?
 
 things to try: '-bf 2', '-flags qprd', '-flags mv0', '-flags skiprd'.
 
 @section Which are good parameters for encoding high quality MPEG-1/MPEG-2?
 

-'-mbd rd -flags +trell -cmp 2 -subcmp 2 -g 100 -pass 1/2'
+'-mbd rd -trellis 2 -cmp 2 -subcmp 2 -g 100 -pass 1/2'

 but beware the '-g 100' might cause problems with some decoders.
 Things to try: '-bf 2', '-flags qprd', '-flags mv0', '-flags skiprd.
 
 but beware the '-g 100' might cause problems with some decoders.
 Things to try: '-bf 2', '-flags qprd', '-flags mv0', '-flags skiprd.
 

-@section Interlaced video looks very bad when encoded with ffmpeg, what is wrong?
+@section Interlaced video looks very bad when encoded with avconv, what is wrong?

 
 You should use '-flags +ilme+ildct' and maybe '-flags +alt' for interlaced
 material, and try '-top 0/1' if the result looks really messed-up.
 
 @section How can I read DirectShow files?
 
 
 You should use '-flags +ilme+ildct' and maybe '-flags +alt' for interlaced
 material, and try '-top 0/1' if the result looks really messed-up.
 
 @section How can I read DirectShow files?
 

-If you have built FFmpeg with @code{./configure --enable-avisynth}
+If you have built Libav with @code{./configure --enable-avisynth}

 (only possible on MinGW/Cygwin platforms),
 then you may use any file that DirectShow can read as input.
 (only possible on MinGW/Cygwin platforms),
 then you may use any file that DirectShow can read as input.

-(Be aware that this feature has been recently added,
-so you will need to help yourself in case of problems.)

 
 Just create an "input.avs" text file with this single line ...
 @example
   DirectShowSource("C:\path to your file\yourfile.asf")
 @end example
 
 Just create an "input.avs" text file with this single line ...
 @example
   DirectShowSource("C:\path to your file\yourfile.asf")
 @end example

-... and then feed that text file to FFmpeg:
+... and then feed that text file to avconv:

 @example
 @example

-  ffmpeg -i input.avs
+  avconv -i input.avs

 @end example
 
 @end example
 

-For ANY other help on Avisynth, please visit @url{http://www.avisynth.org/}.
+For ANY other help on AviSynth, please visit the
+@uref{http://www.avisynth.org/, AviSynth homepage}.

 
 @section How can I join video files?
 
 
 @section How can I join video files?
 


@@ -294,15 +216,14 @@ equally humble @code{copy} under Windows), and finally transcoding back to your
 format of choice.
 
 @example
 format of choice.
 
 @example

-ffmpeg -i input1.avi -sameq intermediate1.mpg
-ffmpeg -i input2.avi -sameq intermediate2.mpg
+avconv -i input1.avi intermediate1.mpg
+avconv -i input2.avi intermediate2.mpg

 cat intermediate1.mpg intermediate2.mpg > intermediate_all.mpg
 cat intermediate1.mpg intermediate2.mpg > intermediate_all.mpg

-ffmpeg -i intermediate_all.mpg -sameq output.avi
+avconv -i intermediate_all.mpg output.avi

 @end example
 
 @end example
 

-Notice that you should either use @code{-sameq} or set a reasonably high
-bitrate for your intermediate and output files, if you want to preserve
-video quality.
+Notice that you should set a reasonably high bitrate for your intermediate and
+output files, if you want to preserve video quality.

 
 Also notice that you may avoid the huge intermediate files by taking advantage
 of named pipes, should your platform support it:
 
 Also notice that you may avoid the huge intermediate files by taking advantage
 of named pipes, should your platform support it:


@@ -310,14 +231,18 @@ of named pipes, should your platform support it:
 @example
 mkfifo intermediate1.mpg
 mkfifo intermediate2.mpg
 @example
 mkfifo intermediate1.mpg
 mkfifo intermediate2.mpg

-ffmpeg -i input1.avi -sameq -y intermediate1.mpg < /dev/null &
-ffmpeg -i input2.avi -sameq -y intermediate2.mpg < /dev/null &
+avconv -i input1.avi -y intermediate1.mpg < /dev/null &
+avconv -i input2.avi -y intermediate2.mpg < /dev/null &

 cat intermediate1.mpg intermediate2.mpg |\
 cat intermediate1.mpg intermediate2.mpg |\

-ffmpeg -f mpeg -i - -sameq -vcodec mpeg4 -acodec libmp3lame output.avi
+avconv -f mpeg -i - -c:v mpeg4 -acodec libmp3lame output.avi

 @end example
 
 Similarly, the yuv4mpegpipe format, and the raw video, raw audio codecs also
 allow concatenation, and the transcoding step is almost lossless.
 @end example
 
 Similarly, the yuv4mpegpipe format, and the raw video, raw audio codecs also
 allow concatenation, and the transcoding step is almost lossless.

+When using multiple yuv4mpegpipe(s), the first line needs to be discarded
+from all but the first stream. This can be accomplished by piping through
+@code{tail} as seen below. Note that when piping through @code{tail} you
+must use command grouping, @code{@{  ;@}}, to background properly.

 
 For example, let's say we want to join two FLV files into an output.flv file:
 
 
 For example, let's say we want to join two FLV files into an output.flv file:
 


@@ -328,43 +253,45 @@ mkfifo temp2.a
 mkfifo temp2.v
 mkfifo all.a
 mkfifo all.v
 mkfifo temp2.v
 mkfifo all.a
 mkfifo all.v

-ffmpeg -i input1.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp1.a < /dev/null &
-ffmpeg -i input2.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp2.a < /dev/null &
-ffmpeg -i input1.flv -an -f yuv4mpegpipe - > temp1.v < /dev/null &
-ffmpeg -i input2.flv -an -f yuv4mpegpipe - > temp2.v < /dev/null &
+avconv -i input1.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp1.a < /dev/null &
+avconv -i input2.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp2.a < /dev/null &
+avconv -i input1.flv -an -f yuv4mpegpipe - > temp1.v < /dev/null &
+@{ avconv -i input2.flv -an -f yuv4mpegpipe - < /dev/null | tail -n +2 > temp2.v ; @} &

 cat temp1.a temp2.a > all.a &
 cat temp1.v temp2.v > all.v &
 cat temp1.a temp2.a > all.a &
 cat temp1.v temp2.v > all.v &

-ffmpeg -f u16le -acodec pcm_s16le -ac 2 -ar 44100 -i all.a \
+avconv -f u16le -acodec pcm_s16le -ac 2 -ar 44100 -i all.a \

        -f yuv4mpegpipe -i all.v \
        -f yuv4mpegpipe -i all.v \

-       -sameq -y output.flv
+       -y output.flv

 rm temp[12].[av] all.[av]
 @end example
 
 rm temp[12].[av] all.[av]
 @end example
 

-@section FFmpeg does not adhere to the -maxrate setting, some frames are bigger than maxrate/fps.
+@section -profile option fails when encoding H.264 video with AAC audio

 
 

-Read the MPEG spec about video buffer verifier.
+@command{avconv} prints an error like

 
 

-@section I want CBR, but no matter what I do frame sizes differ.
-
-You do not understand what CBR is, please read the MPEG spec.
-Read about video buffer verifier and constant bitrate.
-The one sentence summary is that there is a buffer and the input rate is
-constant, the output can vary as needed.
+@example
+Undefined constant or missing '(' in 'baseline'
+Unable to parse option value "baseline"
+Error setting option profile to value baseline.
+@end example

 
 

-@section How do I check if a stream is CBR?
+Short answer: write @option{-profile:v} instead of @option{-profile}.

 
 

-To quote the MPEG-2 spec:
-"There is no way to tell that a bitstream is constant bitrate without
-examining all of the vbv_delay values and making complicated computations."
+Long answer: this happens because the @option{-profile} option can apply to both
+video and audio.  Specifically the AAC encoder also defines some profiles, none
+of which are named @var{baseline}.

 
 

+The solution is to apply the @option{-profile} option to the video stream only
+by using @url{http://libav.org/avconv.html#Stream-specifiers-1, Stream specifiers}.
+Appending @code{:v} to it will do exactly that.

 
 @chapter Development
 
 
 @chapter Development
 

-@section Are there examples illustrating how to use the FFmpeg libraries, particularly libavcodec and libavformat?
+@section Are there examples illustrating how to use the Libav libraries, particularly libavcodec and libavformat?

 
 

-Yes. Read the Developers Guide of the FFmpeg documentation. Alternatively,
+Yes. Read the Developers Guide of the Libav documentation. Alternatively,

 examine the source code for one of the many open source projects that
 examine the source code for one of the many open source projects that

-already incorporate FFmpeg at (@url{projects.html}).
+already incorporate Libav at (@url{projects.html}).

 
 @section Can you support my C compiler XXX?
 
 
 @section Can you support my C compiler XXX?
 


@@ -374,109 +301,54 @@ with @code{#ifdef}s related to the compiler.
 
 @section Is Microsoft Visual C++ supported?
 
 
 @section Is Microsoft Visual C++ supported?
 

-No. Microsoft Visual C++ is not compliant to the C99 standard and does
-not - among other things - support the inline assembly used in FFmpeg.
-If you wish to use MSVC++ for your
-project then you can link the MSVC++ code with libav* as long as
-you compile the latter with a working C compiler. For more information, see
-the @emph{Microsoft Visual C++ compatibility} section in the FFmpeg
-documentation.
-
-There have been efforts to make FFmpeg compatible with MSVC++ in the
-past. However, they have all been rejected as too intrusive, especially
-since MinGW does the job adequately. None of the core developers
-work with MSVC++ and thus this item is low priority. Should you find
-the silver bullet that solves this problem, feel free to shoot it at us.
-
-We strongly recommend you to move over from MSVC++ to MinGW tools.
-
-@section Can I use FFmpeg or libavcodec under Windows?
-
-Yes, but the Cygwin or MinGW tools @emph{must} be used to compile FFmpeg.
-Read the @emph{Windows} section in the FFmpeg documentation to find more
-information.
-
-To get help and instructions for building FFmpeg under Windows, check out
-the FFmpeg Windows Help Forum at
-@url{http://arrozcru.no-ip.org/ffmpeg/}.
+Yes. Please see the @uref{platform.html, Microsoft Visual C++}
+section in the Libav documentation.

 
 @section Can you add automake, libtool or autoconf support?
 
 No. These tools are too bloated and they complicate the build.
 
 
 @section Can you add automake, libtool or autoconf support?
 
 No. These tools are too bloated and they complicate the build.
 

-@section Why not rewrite ffmpeg in object-oriented C++?
+@section Why not rewrite Libav in object-oriented C++?

 
 

-FFmpeg is already organized in a highly modular manner and does not need to
+Libav is already organized in a highly modular manner and does not need to

 be rewritten in a formal object language. Further, many of the developers
 favor straight C; it works for them. For more arguments on this matter,
 be rewritten in a formal object language. Further, many of the developers
 favor straight C; it works for them. For more arguments on this matter,

-read "Programming Religion" at (@url{http://www.tux.org/lkml/#s15}).
-
-@section Why are the ffmpeg programs devoid of debugging symbols?
-
-The build process creates ffmpeg_g, ffplay_g, etc. which contain full debug
-information. Those binaries are stripped to create ffmpeg, ffplay, etc. If
-you need the debug information, used the *_g versions.
+read @uref{http://www.tux.org/lkml/#s15, "Programming Religion"}.

 
 @section I do not like the LGPL, can I contribute code under the GPL instead?
 
 Yes, as long as the code is optional and can easily and cleanly be placed
 
 @section I do not like the LGPL, can I contribute code under the GPL instead?
 
 Yes, as long as the code is optional and can easily and cleanly be placed

-under #ifdef CONFIG_GPL without breaking anything. So for example a new codec
+under #if CONFIG_GPL without breaking anything. So for example a new codec

 or filter would be OK under GPL while a bug fix to LGPL code would not.
 
 or filter would be OK under GPL while a bug fix to LGPL code would not.
 

-@section I want to compile xyz.c alone but my compiler produced many errors.
-
-Common code is in its own files in libav* and is used by the individual
-codecs. They will not work without the common parts, you have to compile
-the whole libav*. If you wish, disable some parts with configure switches.
-You can also try to hack it and remove more, but if you had problems fixing
-the compilation failure then you are probably not qualified for this.
-
-@section I'm using libavcodec from within my C++ application but the linker complains about missing symbols which seem to be available.
+@section I'm using Libav from within my C++ application but the linker complains about missing symbols which seem to be available.

 
 

-FFmpeg is a pure C project, so to use the libraries within your C++ application
+Libav is a pure C project, so to use the libraries within your C++ application

 you need to explicitly state that you are using a C library. You can do this by
 you need to explicitly state that you are using a C library. You can do this by

-encompassing your FFmpeg includes using @code{extern "C"}.
+encompassing your Libav includes using @code{extern "C"}.

 
 See @url{http://www.parashift.com/c++-faq-lite/mixing-c-and-cpp.html#faq-32.3}
 
 
 See @url{http://www.parashift.com/c++-faq-lite/mixing-c-and-cpp.html#faq-32.3}
 

-@section I have a file in memory / a API different from *open/*read/ libc how do I use it with libavformat?
-
-You have to implement a URLProtocol, see libavformat/file.c in FFmpeg
-and libmpdemux/demux_lavf.c in MPlayer sources.
-
-@section I get "No compatible shell script interpreter found." in MSys.
+@section I'm using libavutil from within my C++ application but the compiler complains about 'UINT64_C' was not declared in this scope

 
 

-The standard MSys bash (2.04) is broken. You need to install 2.05 or later.
+Libav is a pure C project using C99 math features, in order to enable C++
+to use them you have to append -D__STDC_CONSTANT_MACROS to your CXXFLAGS

 
 

-@section I get "./configure: line <xxx>: pr: command not found" in MSys.
-
-The standard MSys install doesn't come with pr. You need to get it from the coreutils package.
-
-@section I tried to pass RTP packets into a decoder, but it doesn't work.
-
-RTP is a container format like any other, you must first depacketize the
-codec frames/samples stored in RTP and then feed to the decoder.
-
-@section Where can I find libav* headers for Pascal/Delphi?
-
-see @url{http://www.iversenit.dk/dev/ffmpeg-headers/}
-
-@section Where is the documentation about ffv1, msmpeg4, asv1, 4xm?
+@section I have a file in memory / a API different from *open/*read/ libc how do I use it with libavformat?

 
 

-see @url{http://svn.mplayerhq.hu/michael/trunk/docs/}
+You have to create a custom AVIOContext using @code{avio_alloc_context},
+see @file{libavformat/aviobuf.c} in Libav and @file{libmpdemux/demux_lavf.c} in MPlayer2 sources.

 
 

-@section How do I feed H.263-RTP (and other codecs in RTP) to libavcodec?
+@section Why is @code{make fate} not running all tests?

 
 

-Even if peculiar since it is network oriented, RTP is a container like any
-other. You have to @emph{demux} RTP before feeding the payload to libavcodec.
-In this specific case please look at RFC 4629 to see how it should be done.
+Make sure you have the fate-suite samples and the @code{SAMPLES} Make variable
+or @code{FATE_SAMPLES} environment variable or the @code{--samples}
+@command{configure} option is set to the right path.

 
 

-@section AVStream.r_frame_rate is wrong, it is much larger than the framerate.
+@section Why is @code{make fate} not finding the samples?

 
 

-r_frame_rate is NOT the average framerate, it is the smallest framerate
-that can accurately represent all timestamps. So no, it is not
-wrong if it is larger than the average!
-For example, if you have mixed 25 and 30 fps content, then r_frame_rate
-will be 150.
+Do you happen to have a @code{~} character in the samples path to indicate a
+home directory? The value is used in ways where the shell cannot expand it,
+causing FATE to not find files. Just replace @code{~} by the full path.

 
 @bye
 
 @bye