CLI front-end for the FFmpeg library. Can do tons of conversions and streaming.
Tested on Ubuntu 15.10.
List codecs: http://stackoverflow.com/questions/3377300/what-are-all-codecs-supported-by-ffmpeg
ffmpeg -codecs
ffmpeg can detect file types from both file names and contents. But if you want to be explicit, remember the man ffmpeg signature:
ffmpeg [global_options] {[input_file_options] -i input_file} ... {[output_file_options] output_file} ...
So the -f before -i is for the input format, and the -f after -i is the output.
Example: stream your desktop and play it:
ffmpeg -video_size 640x480 -framerate 25 -f x11grab -i :0.0+100,200 -f h264 - | ffplay -f h264 -
Freedom!
ffmpeg -framerate 4 -pattern_type glob -i '*.jpeg' -c:v vp9 out.webm
TODO: quality is bad.
- http://stackoverflow.com/questions/10380045/is-there-any-easy-way-to-extract-h-264-raw-stream-in-annexb-format
- http://stackoverflow.com/questions/19300350/extracting-h264-raw-video-stream-from-mp4-or-flv-with-ffmpeg-generate-an-invalid
Works:
ffmpeg -i in.mp4 -vcodec copy -bsf h264_mp4toannexb -an -f h264 out.h264
VLC cannot open that output file, but ffplay can. TODO: is the -bsf really needed?
ffmpeg -i in.mts -vcodec copy -an -f h264 out.h264
http://superuser.com/questions/186465/extract-audio-aac-from-mp4
ffmpeg -i in.mp4 -c copy -map 0:a:0 out.aac
https://trac.ffmpeg.org/wiki/Capture/Webcam
First install v4l2, then:
ffmpeg -f v4l2 -framerate 25 -video_size 640x480 -i /dev/video0 -f v8 output.mkv
Get information about video and audio files:
ffprobe a.webm
- http://stackoverflow.com/questions/2017843/fetch-frame-count-with-ffmpeg
- http://superuser.com/questions/84631/how-do-i-get-the-number-of-frames-in-a-video-on-the-linux-command-line
Not easy because it is not stored on the video, it requires decoding.
http://superuser.com/questions/885452/extracting-the-index-of-key-frames-from-a-video-using-ffmpeg
ffprobe -select_streams v \
-show_frames \
-show_entries frame=pict_type \
-of csv \
tmp.h264
generates something like:
frame,I
frame,B
frame,P
frame,B
frame,P
frame,B
frame,P
frame,B
frame,P
frame,B
frame,I
where I, B, and P are defined at: https://en.wikipedia.org/wiki/Video_compression_picture_types
From there on, Bash it up.
- http://superuser.com/questions/624567/ffmpeg-create-a-video-from-images
- http://askubuntu.com/questions/380199/converting-images-into-video
- http://stackoverflow.com/questions/16315192/avconv-make-a-video-from-a-subset-on-images
- https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images
- http://unix.stackexchange.com/questions/68770/converting-png-frames-to-video-at-1-fps
- http://stackoverflow.com/questions/19267443/playback-issues-in-vlc-with-low-fps-video-from-images-using-ffmpeg
Just works:
ffmpeg -framerate 1 -pattern_type glob -i '*.png' -c:v libx264 -r 30 -pix_fmt yuv420p out.mp4
-r 30 to use a standard frame rate and be more compatible, see: http://stackoverflow.com/questions/19267443/playback-issues-in-vlc-with-low-fps-video-from-images-using-ffmpeg/41797724#41797724
- http://stackoverflow.com/questions/7565962/ffmpeg-fade-effects-between-frames
- http://superuser.com/questions/778762/crossfade-between-2-videos-using-ffmpeg
- http://superuser.com/questions/223678/how-to-convert-single-images-into-a-video-with-blending-transition
Minimalistic video preview tool.
ffplay video.mp4
No controls, no nothing, just a window with the video.
Exit when file is over: http://ffmpeg-users.933282.n4.nabble.com/ffplay-does-not-exit-automatically-after-the-file-has-completed-playing-td2969254.html
ffplay -autoexit video.mp4
Loop infinitely:
ffplay -loop -1 video.mp4
Raw audio file:
ffplay -autoexit -f u16be -ar 44100 -ac 1 in.raw
https://trac.ffmpeg.org/wiki/StreamingGuide
https://trac.ffmpeg.org/wiki/ffserver
TODO: what is the IO format: RTMP of HTTP? How is video sent over HTTP?
Note: this project seems very unmaintained, and there are better ones out there.
Server configuration file:
/etc/ffserver.conf
Use a custom one and show server debug:
ffserver -d -f ~/ffserver.conf
Start server:
ffserver
Send video to it. Must edit the VideoFrameRate to something larger than 3... https://lists.ffmpeg.org/pipermail/ffmpeg-user/2016-January/030111.html:
ffmpeg -f v4l2 -s 320x240 -r 25 -i /dev/video0 -f alsa -ac 2 -i hw:1 http://localhost:8090/feed1.ffm
Watch it. Must edit ACL inside feed http://stackoverflow.com/a/13977181/895245 or else access denied:
ffplay http://localhost:8090/test1.mpg
TODO: video has a huge delay from starting up to playing, see: https://trac.ffmpeg.org/wiki/StreamingGuide#Latency
A few URLs that can be accessed from the browser:
- http://localhost:8090/stat.html: show server status
- http://localhost:8090/: redirect to what is fixed at
<Redirect index.html>of the config file - http://localhost:8090/test1.mpg: TODO what happens? Firefox sees a video file type, and redirects to a video app, then when I kill the server the video player plays all that has happened as if from a file.
An FFmpeg invention it seems: http://stackoverflow.com/questions/27930879/what-is-ffmpegs-udp-protocol
- http://stackoverflow.com/questions/18444194/cutting-the-videos-based-on-start-and-end-time-using-ffmpeg/40244234
- http://superuser.com/questions/138331/using-ffmpeg-to-cut-up-video
Best command:
ffmpeg -i in.ogv -ss 00:00 -to 03:30 -c copy out.ogv
- http://ffmpeg.org/faq.html#How-can-I-concatenate-video-files
- http://stackoverflow.com/questions/7333232/concatenate-two-mp4-files-using-ffmpeg
Best command:
ffmpeg -i concat:"in1.ogv|in2.ogv" -c copy out.ogv
http://superuser.com/questions/277642/how-to-merge-audio-and-video-file-in-ffmpeg
Yeah, this works on VLC and YouTube:
ffmpeg -i video.mp4 -i audio.mp3 -c copy output.mkv