format and device.
@example
-ffmpeg -f audio_device -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
+ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
@end example
Note that you must activate the right video source and channel before
launching FFmpeg with any TV viewer such as xawtv
-(@url{http://bytesex.org/xawtv/}) by Gerd Knorr. You also
+(@url{http://linux.bytesex.org/xawtv/}) by Gerd Knorr. You also
have to set the audio recording levels correctly with a
standard mixer.
FFmpeg can grab the X11 display.
@example
-ffmpeg -f x11grab -i :0.0 /tmp/out.mpg
+ffmpeg -f x11grab -s cif -i :0.0 /tmp/out.mpg
@end example
0.0 is display.screen number of your X11 server, same as
the DISPLAY environment variable.
@example
-ffmpeg -f x11grab -i :0.0+10,20 /tmp/out.mpg
+ffmpeg -f x11grab -s cif -i :0.0+10,20 /tmp/out.mpg
@end example
0.0 is display.screen number of your X11 server, same as the DISPLAY environment
ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
@end example
-Converts a.wav to MPEG audio at 22050Hz sample rate.
+Converts a.wav to MPEG audio at 22050 Hz sample rate.
* You can encode to several formats at the same time and define a
mapping from input stream to output streams:
file:index' specifies which input stream is used for each output
stream, in the order of the definition of output streams.
-* You can transcode decrypted VOBs
+* You can transcode decrypted VOBs:
@example
-ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec mp3 -ab 128k snatch.avi
+ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec libmp3lame -ab 128k snatch.avi
@end example
This is a typical DVD ripping example; the input is a VOB file, the
command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
input video. Furthermore, the audio stream is MP3-encoded so you need
-to enable LAME support by passing @code{--enable-mp3lame} to configure.
+to enable LAME support by passing @code{--enable-libmp3lame} to configure.
The mapping is particularly useful for DVD transcoding
to get the desired audio language.
NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
+
+* You can extract images from a video, or create a video from many images:
+
+For extracting images from a video:
+@example
+ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
+@end example
+
+This will extract one video frame per second from the video and will
+output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
+etc. Images will be rescaled to fit the new WxH values.
+
+If you want to extract just a limited number of frames, you can use the
+above command in combination with the -vframes or -t option, or in
+combination with -ss to start extracting from a certain point in time.
+
+For creating a video from many images:
+@example
+ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
+@end example
+
+The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
+composed of three digits padded with zeroes to express the sequence
+number. It is the same syntax supported by the C printf function, but
+only formats accepting a normal integer are suitable.
+
+* You can put many streams of the same type in the output:
+
+@example
+ffmpeg -i test1.avi -i test2.avi -vcodec copy -acodec copy -vcodec copy -acodec copy test12.avi -newvideo -newaudio
+@end example
+
+In addition to the first video and audio streams, the resulting
+output file @file{test12.avi} will contain the second video
+and the second audio stream found in the input streams list.
+
+The @code{-newvideo}, @code{-newaudio} and @code{-newsubtitle}
+options have to be specified immediately after the name of the output
+file to which you want to add them.
@c man end
@chapter Invocation
ffmpeg -i input.avi -b 64k output.avi
@end example
-* To force the frame rate of the input and output file to 24 fps:
-@example
-ffmpeg -r 24 -i input.avi output.avi
-@end example
-
* To force the frame rate of the output file to 24 fps:
@example
ffmpeg -i input.avi -r 24 output.avi
@end example
-* To force the frame rate of input file to 1 fps and the output file to 24 fps:
+* To force the frame rate of the input file (valid for raw formats only)
+to 1 fps and the frame rate of the output file to 24 fps:
@example
-ffmpeg -r 1 -i input.avi -r 24 output.avi
+ffmpeg -r 1 -i input.m2v -r 24 output.avi
@end example
The format option may be needed for raw input files.
@section Main options
@table @option
-@item -L
-Show license.
-
-@item -h
-Show help.
+@include fftools-common-opts.texi
-@item -version
-Show version.
-
-@item -formats
-Show available formats, codecs, protocols, ...
-
-@item -f fmt
+@item -f @var{fmt}
Force format.
-@item -i filename
-input filename
+@item -i @var{filename}
+input file name
@item -y
Overwrite output files.
-@item -t duration
-Set the recording time in seconds.
+@item -t @var{duration}
+Restrict the transcoded/captured video sequence
+to the duration specified in seconds.
@code{hh:mm:ss[.xxx]} syntax is also supported.
-@item -fs limit_size
+@item -fs @var{limit_size}
Set the file size limit.
-@item -ss position
+@item -ss @var{position}
Seek to given time position in seconds.
@code{hh:mm:ss[.xxx]} syntax is also supported.
-@item -itsoffset offset
+@item -itsoffset @var{offset}
Set the input time offset in seconds.
@code{[-]hh:mm:ss[.xxx]} syntax is also supported.
This option affects all the input files that follow it.
Specifying a positive offset means that the corresponding
streams are delayed by 'offset' seconds.
-@item -title string
-Set the title.
-
-@item -timestamp time
+@item -timestamp @var{time}
Set the timestamp.
-@item -author string
-Set the author.
-
-@item -copyright string
-Set the copyright.
+@item -metadata @var{key}=@var{value}
+Set a metadata key/value pair.
-@item -comment string
-Set the comment.
-
-@item -album string
-Set the album.
-
-@item -track number
-Set the track.
-
-@item -year number
-Set the year.
+For example, for setting the title in the output file:
+@example
+ffmpeg -i in.avi -metadata title="my title" out.flv
+@end example
-@item -v verbose
-Control amount of logging.
+@item -v @var{number}
+Set the logging verbosity level.
-@item -target type
+@item -target @var{type}
Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
"ntsc-svcd", ... ). All the format options (bitrate, codecs,
buffer sizes) are then set automatically. You can just type:
ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
@end example
-@item -dframes number
+@item -dframes @var{number}
Set the number of data frames to record.
-@item -scodec codec
+@item -scodec @var{codec}
Force subtitle codec ('copy' to copy stream).
@item -newsubtitle
Add a new subtitle stream to the current output stream.
-@item -slang code
+@item -slang @var{code}
Set the ISO 639 language code (3 letters) of the current subtitle stream.
@end table
@section Video Options
@table @option
-@item -b bitrate
+@item -b @var{bitrate}
Set the video bitrate in bit/s (default = 200 kb/s).
-@item -vframes number
+@item -vframes @var{number}
Set the number of video frames to record.
-@item -r fps
+@item -r @var{fps}
Set frame rate (Hz value, fraction or abbreviation), (default = 25).
-@item -s size
+@item -s @var{size}
Set frame size. The format is @samp{wxh} (ffserver default = 160x128, ffmpeg default = same as source).
The following abbreviations are recognized:
@table @samp
352x288
@item 4cif
704x576
+@item 16cif
+1408x1152
@item qqvga
160x120
@item qvga
1920x1080
@end table
-@item -aspect aspect
+@item -aspect @var{aspect}
Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777).
-@item -croptop size
+@item -croptop @var{size}
Set top crop band size (in pixels).
-@item -cropbottom size
+@item -cropbottom @var{size}
Set bottom crop band size (in pixels).
-@item -cropleft size
+@item -cropleft @var{size}
Set left crop band size (in pixels).
-@item -cropright size
+@item -cropright @var{size}
Set right crop band size (in pixels).
-@item -padtop size
+@item -padtop @var{size}
Set top pad band size (in pixels).
-@item -padbottom size
+@item -padbottom @var{size}
Set bottom pad band size (in pixels).
-@item -padleft size
+@item -padleft @var{size}
Set left pad band size (in pixels).
-@item -padright size
+@item -padright @var{size}
Set right pad band size (in pixels).
-@item -padcolor (hex color)
+@item -padcolor @var{hex_color}
Set color of padded bands. The value for padcolor is expressed
as a six digit hexadecimal number where the first two digits
represent red, the middle two digits green and last two digits
blue (default = 000000 (black)).
@item -vn
Disable video recording.
-@item -bt tolerance
-Set video bitrate tolerance (in bit/s).
-@item -maxrate bitrate
-Set max video bitrate tolerance (in bit/s).
-@item -minrate bitrate
-Set min video bitrate tolerance (in bit/s).
-@item -bufsize size
-Set rate control buffer size (in bits).
-@item -vcodec codec
+@item -bt @var{tolerance}
+Set video bitrate tolerance (in bits, default 4000k).
+Has a minimum value of: (target_bitrate/target_framerate).
+In 1-pass mode, bitrate tolerance specifies how far ratecontrol is
+willing to deviate from the target average bitrate value. This is
+not related to min/max bitrate. Lowering tolerance too much has
+an adverse effect on quality.
+@item -maxrate @var{bitrate}
+Set max video bitrate (in bit/s).
+Requires -bufsize to be set.
+@item -minrate @var{bitrate}
+Set min video bitrate (in bit/s).
+Most useful in setting up a CBR encode:
+@example
+ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
+@end example
+It is of little use elsewise.
+@item -bufsize @var{size}
+Set video buffer verifier buffer size (in bits).
+@item -vcodec @var{codec}
Force video codec to @var{codec}. Use the @code{copy} special value to
tell that the raw codec data must be copied as is.
@item -sameq
Use same video quality as source (implies VBR).
-@item -pass n
-Select the pass number (1 or 2). It is useful to do two pass
-encoding. The statistics of the video are recorded in the first
-pass and the video is generated at the exact requested bitrate
-in the second pass.
+@item -pass @var{n}
+Select the pass number (1 or 2). It is used to do two-pass
+video encoding. The statistics of the video are recorded in the first
+pass into a log file (see also the option -passlogfile),
+and in the second pass that log file is used to generate the video
+at the exact requested bitrate.
+On pass 1, you may just deactivate audio and set output to null,
+examples for Windows and Unix:
+@example
+ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y NUL
+ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y /dev/null
+@end example
-@item -passlogfile file
-Set two pass logfile name to @var{file}.
+@item -passlogfile @var{prefix}
+Set two-pass log file name prefix to @var{prefix}, the default file name
+prefix is ``ffmpeg2pass''. The complete file name will be
+@file{PREFIX-N.log}, where N is a number specific to the output
+stream.
@item -newvideo
Add a new video stream to the current output stream.
+@item -vlang @var{code}
+Set the ISO 639 language code (3 letters) of the current video stream.
+
@end table
@section Advanced Video Options
@table @option
-@item -pix_fmt format
-Set pixel format.
-@item -g gop_size
+@item -pix_fmt @var{format}
+Set pixel format. Use 'list' as parameter to show all the supported
+pixel formats.
+@item -sws_flags @var{flags}
+Set SwScaler flags (only available when compiled with swscale support).
+@item -g @var{gop_size}
Set the group of pictures size.
@item -intra
Use only intra frames.
-@item -vdt n
+@item -vdt @var{n}
Discard threshold.
-@item -qscale q
+@item -qscale @var{q}
Use fixed video quantizer scale (VBR).
-@item -qmin q
+@item -qmin @var{q}
minimum video quantizer scale (VBR)
-@item -qmax q
+@item -qmax @var{q}
maximum video quantizer scale (VBR)
-@item -qdiff q
+@item -qdiff @var{q}
maximum difference between the quantizer scales (VBR)
-@item -qblur blur
-video quantizer scale blur (VBR)
-@item -qcomp compression
-video quantizer scale compression (VBR)
+@item -qblur @var{blur}
+video quantizer scale blur (VBR) (range 0.0 - 1.0)
+@item -qcomp @var{compression}
+video quantizer scale compression (VBR) (default 0.5).
+Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0
-@item -lmin lambda
+@item -lmin @var{lambda}
minimum video lagrange factor (VBR)
-@item -lmax lambda
+@item -lmax @var{lambda}
max video lagrange factor (VBR)
-@item -mblmin lambda
+@item -mblmin @var{lambda}
minimum macroblock quantizer scale (VBR)
-@item -mblmax lambda
+@item -mblmax @var{lambda}
maximum macroblock quantizer scale (VBR)
These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
@end example
-@item -rc_init_cplx complexity
+@item -rc_init_cplx @var{complexity}
initial complexity for single pass encoding
-@item -b_qfactor factor
+@item -b_qfactor @var{factor}
qp factor between P- and B-frames
-@item -i_qfactor factor
+@item -i_qfactor @var{factor}
qp factor between P- and I-frames
-@item -b_qoffset offset
+@item -b_qoffset @var{offset}
qp offset between P- and B-frames
-@item -i_qoffset offset
+@item -i_qoffset @var{offset}
qp offset between P- and I-frames
-@item -rc_eq equation
+@item -rc_eq @var{equation}
Set rate control equation (@pxref{FFmpeg formula
evaluator}) (default = @code{tex^qComp}).
-@item -rc_override override
+@item -rc_override @var{override}
rate control override for specific intervals
-@item -me method
+@item -me_method @var{method}
Set motion estimation method to @var{method}.
Available methods are (from lowest to best quality):
@table @samp
@item phods
@item log
@item x1
+@item hex
+@item umh
@item epzs
(default method)
@item full
exhaustive search (slow and marginally better than epzs)
@end table
-@item -dct_algo algo
+@item -dct_algo @var{algo}
Set DCT algorithm to @var{algo}. Available values are:
@table @samp
@item 0
FF_DCT_ALTIVEC
@end table
-@item -idct_algo algo
+@item -idct_algo @var{algo}
Set IDCT algorithm to @var{algo}. Available values are:
@table @samp
@item 0
FF_IDCT_SIMPLEARM
@end table
-@item -er n
+@item -er @var{n}
Set error resilience to @var{n}.
@table @samp
@item 1
FF_ER_VERY_AGGRESSIVE
@end table
-@item -ec bit_mask
+@item -ec @var{bit_mask}
Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
the following values:
@table @samp
FF_EC_DEBLOCK (default = enabled)
@end table
-@item -bf frames
+@item -bf @var{frames}
Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
-@item -mbd mode
+@item -mbd @var{mode}
macroblock decision
@table @samp
@item 0
Use four motion vector by macroblock (MPEG-4 only).
@item -part
Use data partitioning (MPEG-4 only).
-@item -bug param
+@item -bug @var{param}
Work around encoder bugs that are not auto-detected.
-@item -strict strictness
+@item -strict @var{strictness}
How strictly to follow the standards.
@item -aic
Enable Advanced intra coding (h263+).
Calculate PSNR of compressed frames.
@item -vstats
Dump video coding statistics to @file{vstats_HHMMSS.log}.
-@item -vhook module
-Insert video processing @var{module}. @var{module} contains the module
-name and its parameters separated by spaces.
-@item -top n
+@item -vstats_file @var{file}
+Dump video coding statistics to @var{file}.
+@item -top @var{n}
top=1/bottom=0/auto=-1 field first
-@item -dc precision
+@item -dc @var{precision}
Intra_dc_precision.
-@item -vtag fourcc/tag
+@item -vtag @var{fourcc/tag}
Force video tag/fourcc.
@item -qphist
Show QP histogram.
-@item -vbsf bitstream filter
-Bitstream filters available are "dump_extra", "remove_extra", "noise".
+@item -vbsf @var{bitstream_filter}
+Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump".
+@example
+ffmpeg -i h264.mp4 -vcodec copy -vbsf h264_mp4toannexb -an out.h264
+@end example
@end table
@section Audio Options
@table @option
-@item -aframes number
+@item -aframes @var{number}
Set the number of audio frames to record.
-@item -ar freq
+@item -ar @var{freq}
Set the audio sampling frequency (default = 44100 Hz).
-@item -ab bitrate
+@item -ab @var{bitrate}
Set the audio bitrate in bit/s (default = 64k).
-@item -ac channels
+@item -aq @var{q}
+Set the audio quality (codec-specific, VBR).
+@item -ac @var{channels}
Set the number of audio channels (default = 1).
@item -an
Disable audio recording.
-@item -acodec codec
+@item -acodec @var{codec}
Force audio codec to @var{codec}. Use the @code{copy} special value to
specify that the raw codec data must be copied as is.
@item -newaudio
@example
ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
@end example
-@item -alang code
+@item -alang @var{code}
Set the ISO 639 language code (3 letters) of the current audio stream.
@end table
@section Advanced Audio options:
@table @option
-@item -atag fourcc/tag
+@item -atag @var{fourcc/tag}
Force audio tag/fourcc.
-@item -absf bitstream filter
+@item -absf @var{bitstream_filter}
Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
@end table
@section Subtitle options:
@table @option
-@item -scodec codec
+@item -scodec @var{codec}
Force subtitle codec ('copy' to copy stream).
@item -newsubtitle
Add a new subtitle stream to the current output stream.
-@item -slang code
+@item -slang @var{code}
Set the ISO 639 language code (3 letters) of the current subtitle stream.
+@item -sn
+Disable subtitle recording.
+@item -sbsf @var{bitstream_filter}
+Bitstream filters available are "mov2textsub", "text2movsub".
+@example
+ffmpeg -i file.mov -an -vn -sbsf mov2textsub -scodec copy -f rawvideo sub.txt
+@end example
@end table
@section Audio/Video grab options
@table @option
-@item -vc channel
+@item -vc @var{channel}
Set video grab channel (DV1394 only).
-@item -tvstd standard
+@item -tvstd @var{standard}
Set television standard (NTSC, PAL (SECAM)).
@item -isync
Synchronize read on input.
@section Advanced options
@table @option
-@item -map input stream id[:input stream id]
+@item -map @var{input_stream_id}[:@var{sync_stream_id}]
Set stream mapping from input streams to output streams.
Just enumerate the input streams in the order you want them in the output.
-[input stream id] sets the (input) stream to sync against.
-@item -map_meta_data outfile:infile
-Set meta data information of outfile from infile.
+@var{sync_stream_id} if specified sets the input stream to sync
+against.
+@item -map_meta_data @var{outfile}:@var{infile}
+Set meta data information of @var{outfile} from @var{infile}.
@item -debug
Print specific debug info.
@item -benchmark
When dumping packets, also dump the payload.
@item -bitexact
Only use bit exact algorithms (for codec testing).
-@item -ps size
-Set packet size in bits.
+@item -ps @var{size}
+Set RTP payload size in bytes.
@item -re
Read input at native frame rate. Mainly used to simulate a grab device.
@item -loop_input
Loop over the input stream. Currently it works only for image
streams. This option is used for automatic FFserver testing.
-@item -loop_output number_of_times
+@item -loop_output @var{number_of_times}
Repeatedly loop output for formats that support looping such as animated GIF
(0 will loop the output infinitely).
-@item -threads count
+@item -threads @var{count}
Thread count.
-@item -vsync parameter
+@item -vsync @var{parameter}
Video sync method. Video will be stretched/squeezed to match the timestamps,
it is done by duplicating and dropping frames. With -map you can select from
which stream the timestamps should be taken. You can leave either video or
audio unchanged and sync the remaining stream(s) to the unchanged one.
-@item -async samples_per_second
+@item -async @var{samples_per_second}
Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
the parameter is the maximum samples per second by which the audio is changed.
-async 1 is a special case where only the start of the audio stream is corrected
without any later correction.
+@item -copyts
+Copy timestamps from input to output.
+@item -shortest
+Finish encoding when the shortest input stream ends.
+@item -dts_delta_threshold
+Timestamp discontinuity delta threshold.
+@item -muxdelay @var{seconds}
+Set the maximum demux-decode delay.
+@item -muxpreload @var{seconds}
+Set the initial demux-decode delay.
@end table
-@node FFmpeg formula evaluator
+@section Preset files
+
+A preset file contains a sequence of @var{option}=@var{value} pairs,
+one for each line, specifying a sequence of options which would be
+awkward to specify on the command line. Lines starting with the hash
+('#') character are ignored and are used to provide comments. Check
+the @file{ffpresets} directory in the FFmpeg source tree for examples.
+
+Preset files are specified with the @code{vpre}, @code{apre},
+@code{spre}, and @code{fpre} options. The @code{fpre} option takes the
+filename of the preset instead of a preset name as input and can be
+used for any kind of codec. For the @code{vpre}, @code{apre}, and
+@code{spre} options, the options specified in a preset file are
+applied to the currently selected codec of the same type as the preset
+option.
+
+The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
+preset options identifies the preset file to use according to the
+following rules:
+
+First ffmpeg searches for a file named @var{arg}.ffpreset in the
+directories @file{$HOME/.ffmpeg}, and in the datadir defined at
+configuration time (usually @file{PREFIX/share/ffmpeg}) in that
+order. For example, if the argument is @code{libx264-max}, it will
+search for the file @file{libx264-max.ffpreset}.
+
+If no such file is found, then ffmpeg will search for a file named
+@var{codec_name}-@var{arg}.ffpreset in the above-mentioned
+directories, where @var{codec_name} is the name of the codec to which
+the preset file options will be applied. For example, if you select
+the video codec with @code{-vcodec libx264} and use @code{-vpre max},
+then it will search for the file @file{libx264-max.ffpreset}.
+
+@anchor{FFmpeg formula evaluator}
@section FFmpeg formula evaluator
When evaluating a rate control string, FFmpeg uses an internal formula
The following unary operators are available: @code{+}, @code{-},
@code{(...)}.
+The following statements are available: @code{ld}, @code{st},
+@code{while}.
+
The following functions are available:
@table @var
@item sinh(x)
@item sin(x)
@item cos(x)
@item tan(x)
+@item atan(x)
+@item asin(x)
+@item acos(x)
@item exp(x)
@item log(x)
+@item abs(x)
@item squish(x)
@item gauss(x)
-@item abs(x)
+@item mod(x, y)
@item max(x, y)
@item min(x, y)
+@item eq(x, y)
+@item gte(x, y)
@item gt(x, y)
+@item lte(x, y)
@item lt(x, y)
-@item eq(x, y)
@item bits2qp(bits)
@item qp2bits(qp)
@end table
@section Protocols
-The filename can be @file{-} to read from standard input or to write
+The file name can be @file{-} to read from standard input or to write
to standard output.
FFmpeg also handles many protocols specified with an URL syntax.
-Use 'ffmpeg -formats' to see a list of the supported protocols.
+Use 'ffmpeg -protocols' to see a list of the supported protocols.
The protocol @code{http:} is currently used only to communicate with
FFserver (see the FFserver documentation). When FFmpeg will be a
is about as good as JPEG compression).
@item To have very low audio bitrates, reduce the sampling frequency
-(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
+(down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
@item To have a constant quality (but a variable bitrate), use the option
'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
@end itemize
-
-@chapter external libraries
-
-FFmpeg can be hooked up with a number of external libraries to add support
-for more formats. None of them are used by default, their use has to be
-explicitly requested by passing the appropriate flags to @file{./configure}.
-
-@section AMR
-
-AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
-AMR WB (floating-point mode) and the AMR NB (both floating-point and
-fixed-point mode) reference decoders and encoders.
-
-@itemize
-
-@item For AMR WB floating-point and AMR NB floating point support, go to
-@url{http://www.penguin.cz/~utx/amr} and follow the instructions for building
-the libraries. Pass @code{--enable-amr-nb} and/or @code{--enable-amr-wb} to
-configure to enable the libraries.
-
-@item For AMR NB fixed-point download TS26.073 REL-6 V6.0.0 from
-@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-600.zip}
-and extract the source to the directory @file{libavcodec/amr}.
-You must also add @code{-DMMS_IO} to @code{CFLAGS} in
-@file{libavcodec/amr/makefile}, i.e.
-``@code{CFLAGS = -Wall -pedantic-errors -I. $(CFLAGS_$(MODE)) -D$(VAD) -DMMS_IO}''.
-Pass @code{--enable-amr-nb-fixed} to configure to enable it.
-
-@end itemize
-
-
-@chapter Supported File Formats and Codecs
-
-You can use the @code{-formats} option to have an exhaustive list.
-
-@section File Formats
-
-FFmpeg supports the following file formats through the @code{libavformat}
-library:
-
-@multitable @columnfractions .4 .1 .1 .4
-@item Supported File Format @tab Encoding @tab Decoding @tab Comments
-@item MPEG audio @tab X @tab X
-@item MPEG-1 systems @tab X @tab X
-@tab muxed audio and video
-@item MPEG-2 PS @tab X @tab X
-@tab also known as @code{VOB} file
-@item MPEG-2 TS @tab @tab X
-@tab also known as DVB Transport Stream
-@item ASF@tab X @tab X
-@item AVI@tab X @tab X
-@item WAV@tab X @tab X
-@item Macromedia Flash@tab X @tab X
-@tab Only embedded audio is decoded.
-@item FLV @tab X @tab X
-@tab Macromedia Flash video files
-@item Real Audio and Video @tab X @tab X
-@item Raw AC3 @tab X @tab X
-@item Raw MJPEG @tab X @tab X
-@item Raw MPEG video @tab X @tab X
-@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
-@item Raw CRI ADX audio @tab X @tab X
-@item Raw Shorten audio @tab @tab X
-@item SUN AU format @tab X @tab X
-@item NUT @tab X @tab X @tab NUT Open Container Format
-@item QuickTime @tab X @tab X
-@item MPEG-4 @tab X @tab X
-@tab MPEG-4 is a variant of QuickTime.
-@item Raw MPEG4 video @tab X @tab X
-@item DV @tab X @tab X
-@item 4xm @tab @tab X
-@tab 4X Technologies format, used in some games.
-@item Playstation STR @tab @tab X
-@item Id RoQ @tab @tab X
-@tab Used in Quake III, Jedi Knight 2, other computer games.
-@item Interplay MVE @tab @tab X
-@tab Format used in various Interplay computer games.
-@item WC3 Movie @tab @tab X
-@tab Multimedia format used in Origin's Wing Commander III computer game.
-@item Sega FILM/CPK @tab @tab X
-@tab Used in many Sega Saturn console games.
-@item Westwood Studios VQA/AUD @tab @tab X
-@tab Multimedia formats used in Westwood Studios games.
-@item Id Cinematic (.cin) @tab @tab X
-@tab Used in Quake II.
-@item FLIC format @tab @tab X
-@tab .fli/.flc files
-@item Sierra VMD @tab @tab X
-@tab Used in Sierra CD-ROM games.
-@item Sierra Online @tab @tab X
-@tab .sol files used in Sierra Online games.
-@item Matroska @tab @tab X
-@item Electronic Arts Multimedia @tab @tab X
-@tab Used in various EA games; files have extensions like WVE and UV2.
-@item Nullsoft Video (NSV) format @tab @tab X
-@item ADTS AAC audio @tab X @tab X
-@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
-@item American Laser Games MM @tab @tab X
-@tab Multimedia format used in games like Mad Dog McCree
-@item AVS @tab @tab X
-@tab Multimedia format used by the Creature Shock game.
-@item Smacker @tab @tab X
-@tab Multimedia format used by many games.
-@item GXF @tab X @tab X
-@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
-@item CIN @tab @tab X
-@tab Multimedia format used by Delphine Software games.
-@item MXF @tab @tab X
-@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
-@item SEQ @tab @tab X
-@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
-@item DXA @tab @tab X
-@tab This format is used in non-Windows version of Feeble Files game and
-different game cutscenes repacked for use with ScummVM.
-@item THP @tab @tab X
-@tab Used on the Nintendo GameCube.
-@item C93 @tab @tab X
-@tab Used in the game Cyberia from Interplay.
-@item Bethsoft VID @tab @tab X
-@tab Used in some games from Bethesda Softworks.
-@item CRYO APC @tab @tab X
-@tab Audio format used in some games by CRYO Interactive Entertainment.
-@end multitable
-
-@code{X} means that encoding (resp. decoding) is supported.
-
-@section Image Formats
-
-FFmpeg can read and write images for each frame of a video sequence. The
-following image formats are supported:
-
-@multitable @columnfractions .4 .1 .1 .4
-@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
-@item PGM, PPM @tab X @tab X
-@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
-@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
-@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
-@item .Y.U.V @tab X @tab X @tab one raw file per component
-@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
-@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
-@item Targa @tab @tab X @tab Targa (.TGA) image format.
-@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
-@item SGI @tab X @tab X @tab SGI RGB image format
-@end multitable
-
-@code{X} means that encoding (resp. decoding) is supported.
-
-@section Video Codecs
-
-@multitable @columnfractions .4 .1 .1 .4
-@item Supported Codec @tab Encoding @tab Decoding @tab Comments
-@item MPEG-1 video @tab X @tab X
-@item MPEG-2 video @tab X @tab X
-@item MPEG-4 @tab X @tab X
-@item MSMPEG4 V1 @tab X @tab X
-@item MSMPEG4 V2 @tab X @tab X
-@item MSMPEG4 V3 @tab X @tab X
-@item WMV7 @tab X @tab X
-@item WMV8 @tab X @tab X @tab not completely working
-@item WMV9 @tab @tab X @tab not completely working
-@item VC1 @tab @tab X
-@item H.261 @tab X @tab X
-@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
-@item H.264 @tab @tab X
-@item RealVideo 1.0 @tab X @tab X
-@item RealVideo 2.0 @tab X @tab X
-@item MJPEG @tab X @tab X
-@item lossless MJPEG @tab X @tab X
-@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
-@item Apple MJPEG-B @tab @tab X
-@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
-@item DV @tab X @tab X
-@item HuffYUV @tab X @tab X
-@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
-@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
-@item Asus v1 @tab X @tab X @tab fourcc: ASV1
-@item Asus v2 @tab X @tab X @tab fourcc: ASV2
-@item Creative YUV @tab @tab X @tab fourcc: CYUV
-@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
-@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
-@item On2 VP3 @tab @tab X @tab still experimental
-@item On2 VP5 @tab @tab X @tab fourcc: VP50
-@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62
-@item Theora @tab X @tab X @tab still experimental
-@item Intel Indeo 3 @tab @tab X
-@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
-@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1
-@item ATI VCR1 @tab @tab X @tab fourcc: VCR1
-@item ATI VCR2 @tab @tab X @tab fourcc: VCR2
-@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
-@item 4X Video @tab @tab X @tab Used in certain computer games.
-@item Sony Playstation MDEC @tab @tab X
-@item Id RoQ @tab @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
-@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
-@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
-@item Apple Animation @tab @tab X @tab fourcc: 'rle '
-@item Apple Graphics @tab @tab X @tab fourcc: 'smc '
-@item Apple Video @tab @tab X @tab fourcc: rpza
-@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
-@item Cinepak @tab @tab X
-@item Microsoft RLE @tab @tab X
-@item Microsoft Video-1 @tab @tab X
-@item Westwood VQA @tab @tab X
-@item Id Cinematic Video @tab @tab X @tab Used in Quake II.
-@item Planar RGB @tab @tab X @tab fourcc: 8BPS
-@item FLIC video @tab @tab X
-@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
-@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
-@item VMD Video @tab @tab X @tab Used in Sierra VMD files.
-@item MSZH @tab @tab X @tab Part of LCL
-@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
-@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
-@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
-@item Miro VideoXL @tab @tab X @tab fourcc: VIXL
-@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
-@item LOCO @tab @tab X @tab
-@item Winnov WNV1 @tab @tab X @tab
-@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
-@item Fraps FPS1 @tab @tab X @tab
-@item CamStudio @tab @tab X @tab fourcc: CSCD
-@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
-@item ZMBV @tab X @tab X @tab Encoder works only on PAL8
-@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
-@item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
-@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
-@item KMVC @tab @tab X @tab Codec used in Worms games.
-@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
-@item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
-@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game.
-@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game.
-@item AVID DNxHD @tab @tab X @tab aka SMPTE VC3
-@item C93 Video @tab @tab X @tab Codec used in Cyberia game.
-@item THP @tab @tab X @tab Used on the Nintendo GameCube.
-@item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks.
-@end multitable
-
-@code{X} means that encoding (resp. decoding) is supported.
-
-@section Audio Codecs
-
-@multitable @columnfractions .4 .1 .1 .1 .7
-@item Supported Codec @tab Encoding @tab Decoding @tab Comments
-@item MPEG audio layer 2 @tab IX @tab IX
-@item MPEG audio layer 1/3 @tab IX @tab IX
-@tab MP3 encoding is supported through the external library LAME.
-@item AC3 @tab IX @tab IX
-@tab liba52 is used internally for decoding.
-@item Vorbis @tab X @tab X
-@item WMA V1/V2 @tab X @tab X
-@item AAC @tab X @tab X
-@tab Supported through the external library libfaac/libfaad.
-@item Microsoft ADPCM @tab X @tab X
-@item MS IMA ADPCM @tab X @tab X
-@item QT IMA ADPCM @tab @tab X
-@item 4X IMA ADPCM @tab @tab X
-@item G.726 ADPCM @tab X @tab X
-@item Duck DK3 IMA ADPCM @tab @tab X
-@tab Used in some Sega Saturn console games.
-@item Duck DK4 IMA ADPCM @tab @tab X
-@tab Used in some Sega Saturn console games.
-@item Westwood Studios IMA ADPCM @tab @tab X
-@tab Used in Westwood Studios games like Command and Conquer.
-@item SMJPEG IMA ADPCM @tab @tab X
-@tab Used in certain Loki game ports.
-@item CD-ROM XA ADPCM @tab @tab X
-@item CRI ADX ADPCM @tab X @tab X
-@tab Used in Sega Dreamcast games.
-@item Electronic Arts ADPCM @tab @tab X
-@tab Used in various EA titles.
-@item Creative ADPCM @tab @tab X
-@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
-@item THP ADPCM @tab @tab X
-@tab Used on the Nintendo GameCube.
-@item RA144 @tab @tab X
-@tab Real 14400 bit/s codec
-@item RA288 @tab @tab X
-@tab Real 28800 bit/s codec
-@item RADnet @tab X @tab IX
-@tab Real low bitrate AC3 codec, liba52 is used for decoding.
-@item AMR-NB @tab X @tab X
-@tab Supported through an external library.
-@item AMR-WB @tab X @tab X
-@tab Supported through an external library.
-@item DV audio @tab @tab X
-@item Id RoQ DPCM @tab @tab X
-@tab Used in Quake III, Jedi Knight 2, other computer games.
-@item Interplay MVE DPCM @tab @tab X
-@tab Used in various Interplay computer games.
-@item Xan DPCM @tab @tab X
-@tab Used in Origin's Wing Commander IV AVI files.
-@item Sierra Online DPCM @tab @tab X
-@tab Used in Sierra Online game audio files.
-@item Apple MACE 3 @tab @tab X
-@item Apple MACE 6 @tab @tab X
-@item FLAC lossless audio @tab X @tab X
-@item Shorten lossless audio @tab @tab X
-@item Apple lossless audio @tab @tab X
-@tab QuickTime fourcc 'alac'
-@item FFmpeg Sonic @tab X @tab X
-@tab experimental lossy/lossless codec
-@item Qdesign QDM2 @tab @tab X
-@tab there are still some distortions
-@item Real COOK @tab @tab X
-@tab All versions except 5.1 are supported
-@item DSP Group TrueSpeech @tab @tab X
-@item True Audio (TTA) @tab @tab X
-@item Smacker Audio @tab @tab X
-@item WavPack Audio @tab @tab X
-@item Cin Audio @tab @tab X
-@tab Codec used in Delphine Software games.
-@item Intel Music Coder @tab @tab X
-@item Musepack @tab @tab X
-@tab Only SV7 is supported
-@item DT$ Coherent Audio @tab @tab X
-@item ATRAC 3 @tab @tab X
-@end multitable
-
-@code{X} means that encoding (resp. decoding) is supported.
-
-@code{I} means that an integer-only version is available, too (ensures high
-performance on systems without hardware floating point support).
-
-@chapter Platform Specific information
-
-@section BSD
-
-BSD make will not build FFmpeg, you need to install and use GNU Make
-(@file{gmake}).
-
-@section Windows
-
-To get help and instructions for using FFmpeg under Windows, check out
-the FFmpeg Windows Help Forum at
-@url{http://arrozcru.no-ip.org/ffmpeg/}.
-
-@subsection Native Windows compilation
-
-@itemize
-@item Install the current versions of MSYS and MinGW from
-@url{http://www.mingw.org/}. You can find detailed installation
-instructions in the download section and the FAQ.
-
-NOTE: Use at least bash 3.1. Older versions are known to be failing on the
-configure script.
-
-@item If you want to test the FFplay, also download
-the MinGW development library of SDL 1.2.x
-(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
-@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
-unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
-directory. Edit the @file{sdl-config} script so that it gives the
-correct SDL directory when invoked.
-
-@item Extract the current version of FFmpeg.
-
-@item Start the MSYS shell (file @file{msys.bat}).
-
-@item Change to the FFmpeg directory and follow
- the instructions of how to compile FFmpeg (file
-@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
-suffices. If you have problems using SDL, verify that
-@file{sdl-config} can be launched from the MSYS command line.
-
-@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
-@file{make install}. Do not forget to copy @file{SDL.dll} to the place
-you launch @file{ffplay} from.
-
-@end itemize
-
-Notes:
-@itemize
-
-@item The target @file{make wininstaller} can be used to create a
-Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
-must be copied to the FFmpeg directory in order to build the
-installer.
-
-@item By using @code{./configure --enable-shared} when configuring FFmpeg,
-you can build @file{avcodec.dll} and @file{avformat.dll}. With
-@code{make install} you install the FFmpeg DLLs and the associated
-headers in @file{Program Files/FFmpeg}.
-
-@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
-when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
-C++ @code{lib} tool to build @code{avcodec.lib} and
-@code{avformat.lib}. With these libraries you can link your Visual C++
-code directly with the FFmpeg DLLs (see below).
-
-@end itemize
-
-@subsection Visual C++ compatibility
-
-FFmpeg will not compile under Visual C++ -- and it has too many
-dependencies on the GCC compiler to make a port viable. However,
-if you want to use the FFmpeg libraries in your own applications,
-you can still compile those applications using Visual C++. An
-important restriction to this is that you have to use the
-dynamically linked versions of the FFmpeg libraries (i.e. the
-DLLs), and you have to make sure that Visual-C++-compatible
-import libraries are created during the FFmpeg build process.
-
-This description of how to use the FFmpeg libraries with Visual C++ is
-based on Visual C++ 2005 Express Edition Beta 2. If you have a different
-version, you might have to modify the procedures slightly.
-
-Here are the step-by-step instructions for building the FFmpeg libraries
-so they can be used with Visual C++:
-
-@enumerate
-
-@item Install Visual C++ (if you have not done so already).
-
-@item Install MinGW and MSYS as described above.
-
-@item Add a call to @file{vcvars32.bat} (which sets up the environment
-variables for the Visual C++ tools) as the first line of
-@file{msys.bat}. The standard location for @file{vcvars32.bat} is
-@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
-and the standard location for @file{msys.bat} is
-@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
-following line as the first line of @file{msys.bat}:
-
-@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
-
-@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
-If you get a help message with the command line options of @code{link.exe},
-this means your environment variables are set up correctly, the
-Microsoft linker is on the path and will be used by FFmpeg to
-create Visual-C++-compatible import libraries.
-
-@item Extract the current version of FFmpeg and change to the FFmpeg directory.
-
-@item Type the command
-@code{./configure --enable-shared --disable-static --enable-memalign-hack}
-to configure and, if that did not produce any errors,
-type @code{make} to build FFmpeg.
-
-@item The subdirectories @file{libavformat}, @file{libavcodec}, and
-@file{libavutil} should now contain the files @file{avformat.dll},
-@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
-@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
-DLLs to your System32 directory (typically @file{C:\Windows\System32}).
-
-@end enumerate
-
-And here is how to use these libraries with Visual C++:
-
-@enumerate
-
-@item Create a new console application ("File / New / Project") and then
-select "Win32 Console Application". On the appropriate page of the
-Application Wizard, uncheck the "Precompiled headers" option.
-
-@item Write the source code for your application, or, for testing, just
-copy the code from an existing sample application into the source file
-that Visual C++ has already created for you. (Note that your source
-filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
-compile the FFmpeg headers correctly because in C mode, it does not
-recognize the @code{inline} keyword.) For example, you can copy
-@file{output_example.c} from the FFmpeg distribution (but you will
-have to make minor modifications so the code will compile under
-C++, see below).
-
-@item Open the "Project / Properties" dialog box. In the "Configuration"
-combo box, select "All Configurations" so that the changes you make will
-affect both debug and release builds. In the tree view on the left hand
-side, select "C/C++ / General", then edit the "Additional Include
-Directories" setting to contain the complete paths to the
-@file{libavformat}, @file{libavcodec}, and @file{libavutil}
-subdirectories of your FFmpeg directory. Note that the directories have
-to be separated using semicolons. Now select "Linker / General" from the
-tree view and edit the "Additional Library Directories" setting to
-contain the same three directories.
-
-@item Still in the "Project / Properties" dialog box, select "Linker / Input"
-from the tree view, then add the files @file{avformat.lib},
-@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
-Dependencies". Note that the names of the libraries have to be separated
-using spaces.
-
-@item Now, select "C/C++ / Code Generation" from the tree view. Select
-"Debug" in the "Configuration" combo box. Make sure that "Runtime
-Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
-the "Configuration" combo box and make sure that "Runtime Library" is
-set to "Multi-threaded DLL".
-
-@item Click "OK" to close the "Project / Properties" dialog box and build
-the application. Hopefully, it should compile and run cleanly. If you
-used @file{output_example.c} as your sample application, you will get a
-few compiler errors, but they are easy to fix. The first type of error
-occurs because Visual C++ does not allow an @code{int} to be converted to
-an @code{enum} without a cast. To solve the problem, insert the required
-casts (this error occurs once for a @code{CodecID} and once for a
-@code{CodecType}). The second type of error occurs because C++ requires
-the return value of @code{malloc} to be cast to the exact type of the
-pointer it is being assigned to. Visual C++ will complain that, for
-example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
-an explicit cast. So insert an explicit cast in these places to silence
-the compiler. The third type of error occurs because the @code{snprintf}
-library function is called @code{_snprintf} under Visual C++. So just
-add an underscore to fix the problem. With these changes,
-@file{output_example.c} should compile under Visual C++, and the
-resulting executable should produce valid video files.
-
-@end enumerate
-
-@subsection Cross compilation for Windows with Linux
-
-You must use the MinGW cross compilation tools available at
-@url{http://www.mingw.org/}.
-
-Then configure FFmpeg with the following options:
-@example
-./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
-@end example
-(you can change the cross-prefix according to the prefix chosen for the
-MinGW tools).
-
-Then you can easily test FFmpeg with Wine
-(@url{http://www.winehq.com/}).
-
-@subsection Compilation under Cygwin
-
-Cygwin works very much like Unix.
-
-Just install your Cygwin with all the "Base" packages, plus the
-following "Devel" ones:
-@example
-binutils, gcc-core, make, subversion
-@end example
-
-Do not install binutils-20060709-1 (they are buggy on shared builds);
-use binutils-20050610-1 instead.
-
-Then run
-
-@example
-./configure --enable-static --disable-shared
-@end example
-
-to make a static build or
-
-@example
-./configure --enable-shared --disable-static
-@end example
-
-to build shared libraries.
-
-If you want to build FFmpeg with additional libraries, download Cygwin
-"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
-and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
-(@url{http://cygwinports.dotsrc.org/}).
-
-@subsection Crosscompilation for Windows under Cygwin
-
-With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
-
-Just install your Cygwin as explained before, plus these additional
-"Devel" packages:
-@example
-gcc-mingw-core, mingw-runtime, mingw-zlib
-@end example
-
-and add some special flags to your configure invocation.
-
-For a static build run
-@example
-./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
-@end example
-
-and for a build with shared libraries
-@example
-./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
-@end example
-
-@section BeOS
-
-The configure script should guess the configuration itself.
-Networking support is currently not finished.
-errno issues fixed by Andrew Bachmann.
-
-Old stuff:
-
-François Revol - revol at free dot fr - April 2002
-
-The configure script should guess the configuration itself,
-however I still did not test building on the net_server version of BeOS.
-
-FFserver is broken (needs poll() implementation).
-
-There are still issues with errno codes, which are negative in BeOS, and
-that FFmpeg negates when returning. This ends up turning errors into
-valid results, then crashes.
-(To be fixed)
-
-@chapter Developers Guide
-
-@section API
-@itemize @bullet
-@item libavcodec is the library containing the codecs (both encoding and
-decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
-
-@item libavformat is the library containing the file format handling (mux and
-demux code for several formats). Look at @file{ffplay.c} to use it in a
-player. See @file{output_example.c} to use it to generate audio or video
-streams.
-
-@end itemize
-
-@section Integrating libavcodec or libavformat in your program
-
-You can integrate all the source code of the libraries to link them
-statically to avoid any version problem. All you need is to provide a
-'config.mak' and a 'config.h' in the parent directory. See the defines
-generated by ./configure to understand what is needed.
-
-You can use libavcodec or libavformat in your commercial program, but
-@emph{any patch you make must be published}. The best way to proceed is
-to send your patches to the FFmpeg mailing list.
-
-@node Coding Rules
-@section Coding Rules
-
-FFmpeg is programmed in the ISO C90 language with a few additional
-features from ISO C99, namely:
-@itemize @bullet
-@item
-the @samp{inline} keyword;
-@item
-@samp{//} comments;
-@item
-designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
-@item
-compound literals (@samp{x = (struct s) @{ 17, 23 @};})
-@end itemize
-
-These features are supported by all compilers we care about, so we will not
-accept patches to remove their use unless they absolutely do not impair
-clarity and performance.
-
-All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
-compiles with several other compilers, such as the Compaq ccc compiler
-or Sun Studio 9, and we would like to keep it that way unless it would
-be exceedingly involved. To ensure compatibility, please do not use any
-additional C99 features or GCC extensions. Especially watch out for:
-@itemize @bullet
-@item
-mixing statements and declarations;
-@item
-@samp{long long} (use @samp{int64_t} instead);
-@item
-@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
-@item
-GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
-@end itemize
-
-Indent size is 4.
-The presentation is the one specified by 'indent -i4 -kr -nut'.
-The TAB character is forbidden outside of Makefiles as is any
-form of trailing whitespace. Commits containing either will be
-rejected by the Subversion repository.
-
-Main priority in FFmpeg is simplicity and small code size (=less
-bugs).
-
-Comments: Use the JavaDoc/Doxygen
-format (see examples below) so that code documentation
-can be generated automatically. All nontrivial functions should have a comment
-above them explaining what the function does, even if it is just one sentence.
-All structures and their member variables should be documented, too.
-@example
-/**
- * @@file mpeg.c
- * MPEG codec.
- * @@author ...
- */
-
-/**
- * Summary sentence.
- * more text ...
- * ...
- */
-typedef struct Foobar@{
- int var1; /**< var1 description */
- int var2; ///< var2 description
- /** var3 description */
- int var3;
-@} Foobar;
-
-/**
- * Summary sentence.
- * more text ...
- * ...
- * @@param my_parameter description of my_parameter
- * @@return return value description
- */
-int myfunc(int my_parameter)
-...
-@end example
-
-fprintf and printf are forbidden in libavformat and libavcodec,
-please use av_log() instead.
-
-@section Development Policy
-
-@enumerate
-@item
- You must not commit code which breaks FFmpeg! (Meaning unfinished but
- enabled code which breaks compilation or compiles but does not work or
- breaks the regression tests)
- You can commit unfinished stuff (for testing etc), but it must be disabled
- (#ifdef etc) by default so it does not interfere with other developers'
- work.
-@item
- You do not have to over-test things. If it works for you, and you think it
- should work for others, then commit. If your code has problems
- (portability, triggers compiler bugs, unusual environment etc) they will be
- reported and eventually fixed.
-@item
- Do not commit unrelated changes together, split them into self-contained
- pieces. Also do not forget that if part B depends on part A, but A does not
- depend on B, then A can and should be committed first and separate from B.
- Keeping changes well split into self-contained parts makes reviewing and
- understanding them on the commit log mailing list easier. This also helps
- in case of debugging later on.
- Also if you have doubts about splitting or not splitting, do not hesitate to
- ask/discuss it on the developer mailing list.
-@item
- Do not change behavior of the program (renaming options etc) without
- first discussing it on the ffmpeg-devel mailing list. Do not remove
- functionality from the code. Just improve!
-
- Note: Redundant code can be removed.
-@item
- Do not commit changes to the build system (Makefiles, configure script)
- which change behavior, defaults etc, without asking first. The same
- applies to compiler warning fixes, trivial looking fixes and to code
- maintained by other developers. We usually have a reason for doing things
- the way we do. Send your changes as patches to the ffmpeg-devel mailing
- list, and if the code maintainers say OK, you may commit. This does not
- apply to files you wrote and/or maintain.
-@item
- We refuse source indentation and other cosmetic changes if they are mixed
- with functional changes, such commits will be rejected and removed. Every
- developer has his own indentation style, you should not change it. Of course
- if you (re)write something, you can use your own style, even though we would
- prefer if the indentation throughout FFmpeg was consistent (Many projects
- force a given indentation style - we do not.). If you really need to make
- indentation changes (try to avoid this), separate them strictly from real
- changes.
-
- NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
- then either do NOT change the indentation of the inner part within (do not
- move it to the right)! or do so in a separate commit
-@item
- Always fill out the commit log message. Describe in a few lines what you
- changed and why. You can refer to mailing list postings if you fix a
- particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
-@item
- If you apply a patch by someone else, include the name and email address in
- the log message. Since the ffmpeg-cvslog mailing list is publicly
- archived you should add some SPAM protection to the email address. Send an
- answer to ffmpeg-devel (or wherever you got the patch from) saying that
- you applied the patch.
-@item
- When applying patches that have been discussed (at length) on the mailing
- list, reference the thread in the log message.
-@item
- Do NOT commit to code actively maintained by others without permission.
- Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
- timeframe (12h for build failures and security fixes, 3 days small changes,
- 1 week for big patches) then commit your patch if you think it is OK.
- Also note, the maintainer can simply ask for more time to review!
-@item
- Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
- are sent there and reviewed by all the other developers. Bugs and possible
- improvements or general questions regarding commits are discussed there. We
- expect you to react if problems with your code are uncovered.
-@item
- Update the documentation if you change behavior or add features. If you are
- unsure how best to do this, send a patch to ffmpeg-devel, the documentation
- maintainer(s) will review and commit your stuff.
-@item
- Try to keep important discussions and requests (also) on the public
- developer mailing list, so that all developers can benefit from them.
-@item
- Never write to unallocated memory, never write over the end of arrays,
- always check values read from some untrusted source before using them
- as array index or other risky things.
-@item
- Remember to check if you need to bump versions for the specific libav
- parts (libavutil, libavcodec, libavformat) you are changing. You need
- to change the version integer and the version string.
- Incrementing the first component means no backward compatibility to
- previous versions (e.g. removal of a function from the public API).
- Incrementing the second component means backward compatible change
- (e.g. addition of a function to the public API).
- Incrementing the third component means a noteworthy binary compatible
- change (e.g. encoder bug fix that matters for the decoder).
-@item
- If you add a new codec, remember to update the changelog, add it to
- the supported codecs table in the documentation and bump the second
- component of the @file{libavcodec} version number appropriately. If
- it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
- is only a decoder.
-@item
- Do not change code to hide warnings without ensuring that the underlying
- logic is correct and thus the warning was inappropriate.
-@end enumerate
-
-We think our rules are not too hard. If you have comments, contact us.
-
-Note, these rules are mostly borrowed from the MPlayer project.
-
-@section Submitting patches
-
-First, (@pxref{Coding Rules}) above if you did not yet.
-
-When you submit your patch, try to send a unified diff (diff '-up'
-option). I cannot read other diffs :-)
-
-Also please do not submit patches which contain several unrelated changes.
-Split them into individual self-contained patches; this makes reviewing
-them much easier.
-
-Run the regression tests before submitting a patch so that you can
-verify that there are no big problems.
-
-Patches should be posted as base64 encoded attachments (or any other
-encoding which ensures that the patch will not be trashed during
-transmission) to the ffmpeg-devel mailing list, see
-@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
-
-It also helps quite a bit if you tell us what the patch does (for example
-'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
-and has no lrint()')
-
-Also please if you send several patches, send each patch as separate mail,
-do not attach several unrelated patches to the same mail.
-
-@section patch submission checklist
-
-@enumerate
-@item
- Do the regression tests pass with the patch applied?
-@item
- Is the patch a unified diff?
-@item
- Is the patch against latest FFmpeg SVN?
-@item
- Are you subscribed to ffmpeg-dev?
- (the list is subscribers only due to spam)
-@item
- Have you checked that the changes are minimal, so that the same cannot be
- achieved with a smaller patch and/or simpler final code?
-@item
- If the change is to speed critical code, did you benchmark it?
-@item
- Have you checked that the patch does not introduce buffer overflows or
- other security issues?
-@item
- Is the patch created from the root of the source tree, so it can be
- applied with @code{patch -p0}?
-@item
- Does the patch not mix functional and cosmetic changes?
-@item
- Is the patch attached to the email you send?
-@item
- Is the mime type of the patch correct? It should be text/x-diff or
- text/x-patch or at least text/plain and not application/octet-stream.
-@item
- If the patch fixes a bug, did you provide a verbose analysis of the bug?
-@item
- If the patch fixes a bug, did you provide enough information, including
- a sample, so the bug can be reproduced and the fix can be verified?
-@item
- Did you provide a verbose summary about what the patch does change?
-@item
- Did you provide a verbose explanation why it changes things like it does?
-@item
- Did you provide a verbose summary of the user visible advantages and
- disadvantages if the patch is applied?
-@item
- Did you provide an example so we can verify the new feature added by the
- patch easily?
-@item
- If you did any benchmarks, did you provide them in the mail?
-@item
- If you added a new file, did you insert a license header? It should be
- taken from FFmpeg, not randomly copy and pasted from somewhere else.
-@end enumerate
-
-@section Patch review process
-
-All patches posted to ffmpeg-devel will be reviewed, unless they contain a
-clear note that the patch is not for SVN.
-Reviews and comments will be posted as replies to the patch on the
-mailing list. The patch submitter then has to take care of every comment,
-that can be by resubmitting a changed patch or by discussion. Resubmitted
-patches will themselves be reviewed like any other patch. If at some point
-a patch passes review with no comments then it is approved, that can for
-simple and small patches happen immediately while large patches will generally
-have to be changed and reviewed many times before they are approved.
-After a patch is approved it will be committed to the repository.
-
-We will review all submitted patches, but sometimes we are quite busy so
-especially for large patches this can take several weeks.
-
-When resubmitting patches, please do not make any significant changes
-not related to the comments received during review. Such patches will
-be rejected. Instead, submit significant changes or new features as
-separate patches.
-
-@section Regression tests
-
-Before submitting a patch (or committing to the repository), you should at least
-test that you did not break anything.
-
-The regression tests build a synthetic video stream and a synthetic
-audio stream. These are then encoded and decoded with all codecs or
-formats. The CRC (or MD5) of each generated file is recorded in a
-result file. A 'diff' is launched to compare the reference results and
-the result file.
-
-The regression tests then go on to test the FFserver code with a
-limited set of streams. It is important that this step runs correctly
-as well.
-
-Run 'make test' to test all the codecs and formats.
-
-Run 'make fulltest' to test all the codecs, formats and FFserver.
-
-[Of course, some patches may change the results of the regression tests. In
-this case, the reference results of the regression tests shall be modified
-accordingly].
-
@bye