下载最新的4.1版本的Windows 64位FFmpeg，FFmpeg是一个快速的音频/视频转换工具，FFmpeg可以作为一个命令行程序单独使用。
通过执行以下命令将FFmpeg信息重定位到ffmpeg_help.txt文件中便于查看，其内容如下，FFmpeg使用方法为：ffmpeg.exe [options] [[infile options] -i infile]... {[outfile options] outfile}...
ffmpeg.exe --help > ffmpeg_help.txtHyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
Getting help:
-h -- print basic options
-h long -- print more options
-h full -- print all options (including all format and codec specific options, very long)
-h type=name -- print all options for the named decoder/encoder/demuxer/muxer/filter/bsf
See man ffmpeg for detailed description of the options.
Print help / information / capabilities:
-L show license
-h topic show help
-? topic show help
-help topic show help
--help topic show help
-version show version
-buildconf show build configuration
-formats show available formats
-muxers show available muxers
-demuxers show available demuxers
-devices show available devices
-codecs show available codecs
-decoders show available decoders
-encoders show available encoders
-bsfs show available bit stream filters
-protocols show available protocols
-filters show available filters
-pix_fmts show available pixel formats
-layouts show standard channel layouts
-sample_fmts show available audio sample formats
-colors show available color names
-sources device list sources of the input device
-sinks device list sinks of the output device
-hwaccels show available HW acceleration methods
Global options (affect whole program instead of just one file:
-loglevel loglevel set logging level
-v loglevel set logging level
-report generate a report
-max_alloc bytes set maximum size of a single allocated block
-y overwrite output files
-n never overwrite output files
-ignore_unknown Ignore unknown stream types
-filter_threads number of non-complex filter threads
-filter_complex_threads number of threads for -filter_complex
-stats print progress report during encoding
-max_error_rate maximum error rate ratio of errors (0.0: no errors, 1.0: 100% errors) above which ffmpeg returns an error instead of success.
-bits_per_raw_sample number set the number of bits per raw sample
-vol volume change audio volume (256=normal)
Per-file main options:
-f fmt force format
-c codec codec name
-codec codec codec name
-pre preset preset name
-map_metadata outfile[,metadata]:infile[,metadata] set metadata information of outfile from infile
-t duration record or transcode "duration" seconds of audio/video
-to time_stop record or transcode stop time
-fs limit_size set the limit file size in bytes
-ss time_off set the start time offset
-sseof time_off set the start time offset relative to EOF
-seek_timestamp enable/disable seeking by timestamp with -ss
-timestamp time set the recording timestamp ('now' to set the current time)
-metadata string=string add metadata
-program title=string:st=number... add program with specified streams
-target type specify target file type ("vcd", "svcd", "dvd", "dv" or "dv50" with optional prefixes "pal-", "ntsc-" or "film-")
-apad audio pad
-frames number set the number of frames to output
-filter filter_graph set stream filtergraph
-filter_script filename read stream filtergraph description from a file
-reinit_filter reinit filtergraph on input parameter changes
-discard discard
-disposition disposition
Video options:
-vframes number set the number of video frames to output
-r rate set frame rate (Hz value, fraction or abbreviation)
-s size set frame size (WxH or abbreviation)
-aspect aspect set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)
-bits_per_raw_sample number set the number of bits per raw sample
-vn disable video
-vcodec codec force video codec ('copy' to copy stream)
-timecode hh:mm:ss[:;.]ff set initial TimeCode value.
-pass n select the pass number (1 to 3)
-vf filter_graph set video filters
-ab bitrate audio bitrate (please use -b:a)
-b bitrate video bitrate (please use -b:v)
-dn disable data
Audio options:
-aframes number set the number of audio frames to output
-aq quality set audio quality (codec-specific)
-ar rate set audio sampling rate (in Hz)
-ac channels set number of audio channels
-an disable audio
-acodec codec force audio codec ('copy' to copy stream)
-vol volume change audio volume (256=normal)
-af filter_graph set audio filters
Subtitle options:
-s size set frame size (WxH or abbreviation)
-sn disable subtitle
-scodec codec force subtitle codec ('copy' to copy stream)
-stag fourcc/tag force subtitle tag/fourcc
-fix_sub_duration fix subtitles duration
-canvas_size size set canvas size (WxH or abbreviation)
-spre preset set the subtitle options to the indicated preset以下汇总FFmpeg的常用操作：
1. 在Windows上查看已连接的捕获设备(capture devices)如摄像头，执行以下命令，如果安装了DirectShow也可以将vfwcap替换为dshow：
ffmpeg.exe -y -f vfwcap -i list
ffmpeg.exe -list_devices true -f dshow -i dummy在Windows上将从capture device上获取的视频流数据保存成mp4文件，执行：
ffmpeg.exe -y -f vfwcap -r 25 -i 0 out.mp42. 在Linux上，当插上usb摄像头(/dev/video0)时，查看可用设备的可用格式(包括支持的像素格式、视频格式、帧大小)，执行：
./ffmpeg -f v4l2 -list_formats all -i /dev/video0在Linux上将从/dev/video0上获取的视频流数据保存成mkv文件，执行：
./ffmpeg -f v4l2 -framerate 25 -video_size 640x480 -input_format mjpeg -i /dev/video0 output.mkv3. 在不同的媒体文件之间转换，如将1.mkv转换为1.mp4并设置其大小为1920x1080，执行：
ffmpeg.exe -i 1.mkv -s 1920x1080 1.mp44. 从视频文件中提取图像，如从视频文件tree.avi中提取图像并保存成png，图像名为image-001.png, image-002.png等，执行：
ffmpeg.exe -i tree.avi -r 1 -f image2 image-%3d.png5. 压缩视频文件，如减少视频比特率(video bit rate)，执行：
ffmpeg.exe -i tree.avi -b:v 100k tree2.avi6. 剪切视频文件，如开始剪切的时间点为10秒处(00:00:10)，剪切时间长度为5秒，则执行：
ffmpeg.exe -i tree.avi -ss 00:00:10 -t 5 tree.mp47. 将rtsp视频流保存成视频文件，执行：
ffmpeg.exe -i rtsp://184.72.239.149/vod/mp4://BigBuckBunny_115k.mov -vcodec copy out.mp48. 在windows上获取视频设备名，执行：
ffmpeg.exe -list_devices true -f dshow -i dummy9. 在windows上获取指定视频设备支持的编解码格式及视频size，执行：
ffmpeg.exe -f dshow -list_options true -i video="Integrated Webcam"10. 在windows上通过dshow生成mjpeg数据，执行：
ffmpeg.exe -f dshow -vcodec mjpeg -s 640x480 -framerate 30 -i video="Integrated Webcam" outfile.mpg
