> tldr.sh is a community maintained database of examples, for example you can run it as tldr grep. Lots of people have told me they find it useful.
+1 for tldr. For example, here's the output of `tldr ffmpeg`:
ffmpeg
Video conversion tool.
See also: `gst-launch-1.0`.
More information: https://ffmpeg.org/ffmpeg.html#Options.
- Extract the sound from a video and save it as MP3:
ffmpeg -i path/to/video.mp4 -vn path/to/sound.mp3
- Transcode a FLAC file to Red Book CD format (44100kHz, 16bit):
ffmpeg -i path/to/input_audio.flac -ar 44100 -sample_fmt s16 path/to/output_audio.wav
- Save a video as GIF, scaling the height to 1000px and setting framerate to 15:
ffmpeg -i path/to/video.mp4 -filter:v 'scale=-1:1000' -r 15 path/to/output.gif
- Combine numbered images (frame_1.jpg, frame_2.jpg, etc) into a video or GIF:
ffmpeg -i path/to/frame_%d.jpg -f image2 video.mpg|video.gif
- Trim a video from a given start time mm:ss to an end time mm2:ss2 (omit the -to flag to trim till the end):
ffmpeg -i path/to/input_video.mp4 -ss mm:ss -to mm2:ss2 -codec copy path/to/output_video.mp4
- Convert AVI video to MP4. AAC Audio @ 128kbit, h264 Video @ CRF 23:
ffmpeg -i path/to/input_video.avi -codec:a aac -b:a 128k -codec:v libx264 -crf 23 path/to/output_video.mp4
- Remux MKV video to MP4 without re-encoding audio or video streams:
ffmpeg -i path/to/input_video.mkv -codec copy path/to/output_video.mp4
- Convert MP4 video to VP9 codec. For the best quality, use a CRF value (recommended range 15-35) and -b:v MUST be 0:
ffmpeg -i path/to/input_video.mp4 -codec:v libvpx-vp9 -crf 30 -b:v 0 -codec:a libopus -vbr on -threads number_of_threads path/to/output_video.webm