Skip to content

F
Ffmpeg

小白菜888 / Ffmpeg

通知 3
Star 0
Fork 0
F
Ffmpeg

体验新版 GitCode，发现更多精彩内容 >>

提交 76561924 编写于 作者: S Stefano Sabatini
浏览文件
操作

Move section EXAMPLES towards the end of the ffmpeg-doc.texi file. 

This is consistent with the the rendered ordering of the ffmpeg man
page.

Originally committed as revision 23445 to svn://svn.ffmpeg.org/ffmpeg/trunk
上级 b26247ed
隐藏空白更改
内联 并排
Showing with 160 addition and 160 deletion
doc/ffmpeg-doc.texi
浏览文件 @ 76561924
......@@ -50,166 +50,6 @@ specified for the inputs.
@c man end DESCRIPTION
@chapter Examples
@c man begin EXAMPLES
@section Video and Audio grabbing
FFmpeg can grab video and audio from devices given that you specify the input
format and device.
@example
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://linux.bytesex.org/xawtv/}) by Gerd Knorr. You also
have to set the audio recording levels correctly with a
standard mixer.
@section X11 grabbing
FFmpeg can grab the X11 display.
@example
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 -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
variable. 10 is the x-offset and 20 the y-offset for the grabbing.
@section Video and Audio file format conversion
* FFmpeg can use any supported file format and protocol as input:
Examples:
* You can use YUV files as input:
@example
ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
@end example
It will use the files:
@example
/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
@end example
The Y files use twice the resolution of the U and V files. They are
raw files, without header. They can be generated by all decent video
decoders. You must specify the size of the image with the @option{-s} option
if FFmpeg cannot guess it.
* You can input from a raw YUV420P file:
@example
ffmpeg -i /tmp/test.yuv /tmp/out.avi
@end example
test.yuv is a file containing raw YUV planar data. Each frame is composed
of the Y plane followed by the U and V planes at half vertical and
horizontal resolution.
* You can output to a raw YUV420P file:
@example
ffmpeg -i mydivx.avi hugefile.yuv
@end example
* You can set several input files and output files:
@example
ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
@end example
Converts the audio file a.wav and the raw YUV video file a.yuv
to MPEG file a.mpg.
* You can also do audio and video conversions at the same time:
@example
ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
@end example
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:
@example
ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0
@end example
Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
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:
@example
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
output an AVI file with MPEG-4 video and MP3 audio. Note that in this
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-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
@section Syntax
......@@ -947,6 +787,166 @@ It allows almost lossless encoding.
@end itemize
@c man end TIPS
@chapter Examples
@c man begin EXAMPLES
@section Video and Audio grabbing
FFmpeg can grab video and audio from devices given that you specify the input
format and device.
@example
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://linux.bytesex.org/xawtv/}) by Gerd Knorr. You also
have to set the audio recording levels correctly with a
standard mixer.
@section X11 grabbing
FFmpeg can grab the X11 display.
@example
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 -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
variable. 10 is the x-offset and 20 the y-offset for the grabbing.
@section Video and Audio file format conversion
* FFmpeg can use any supported file format and protocol as input:
Examples:
* You can use YUV files as input:
@example
ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
@end example
It will use the files:
@example
/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
@end example
The Y files use twice the resolution of the U and V files. They are
raw files, without header. They can be generated by all decent video
decoders. You must specify the size of the image with the @option{-s} option
if FFmpeg cannot guess it.
* You can input from a raw YUV420P file:
@example
ffmpeg -i /tmp/test.yuv /tmp/out.avi
@end example
test.yuv is a file containing raw YUV planar data. Each frame is composed
of the Y plane followed by the U and V planes at half vertical and
horizontal resolution.
* You can output to a raw YUV420P file:
@example
ffmpeg -i mydivx.avi hugefile.yuv
@end example
* You can set several input files and output files:
@example
ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
@end example
Converts the audio file a.wav and the raw YUV video file a.yuv
to MPEG file a.mpg.
* You can also do audio and video conversions at the same time:
@example
ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
@end example
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:
@example
ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0
@end example
Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
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:
@example
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
output an AVI file with MPEG-4 video and MP3 audio. Note that in this
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-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 EXAMPLES
@ignore
@setfilename ffmpeg
......
Markdown is supported
0% 或 .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑！
想要评论请 注册 或