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+# FFmpeg cheat sheet
+
+A list of useful commands for the ffmpeg command line tool.
+
+Download FFmpeg: <https://www.ffmpeg.org/download.html>
+
+Full documentation: <https://www.ffmpeg.org/ffmpeg.html>
+
+## Basic conversion
+
+```bash
+ffmpeg -i in.mp4 out.avi
+```
+
+### Remux an MKV file into MP4
+
+```bash
+ffmpeg -i in.mkv -c:v copy -c:a copy out.mp4
+```
+
+### High-quality encoding
+
+Use the `crf` (Constant Rate Factor) parameter to control the output quality.
+The lower crf, the higher the quality (range: 0-51). The default value is 23,
+and visually lossless compression corresponds to `-crf 18`. Use the `preset`
+parameter to control the speed of the compression process.
+Additional info: <https://trac.ffmpeg.org/wiki/Encode/H.264>
+
+```bash
+ffmpeg -i in.mp4 -preset slower -crf 18 out.mp4
+```
+
+## Trimming
+
+Without re-encoding:
+
+```bash
+ffmpeg -ss [start] -i in.mp4 -t [duration] -c copy out.mp4
+```
+
+- [`-ss`](http://ffmpeg.org/ffmpeg-all.html#Main-options) specifies
+  the start time, e.g. `00:01:23.000` or `83` (in seconds)
+- [`-t`](http://ffmpeg.org/ffmpeg-all.html#Main-options) specifies the duration
+  of the clip (same format).
+- Recent `ffmpeg` also has a flag to supply the end time with `-to`.
+- [`-c`](http://ffmpeg.org/ffmpeg-all.html#Main-options) copy copies the first
+  video, audio, and subtitle bitstream from the input to the output file without
+  re-encoding them. This won't harm the quality and make the command run within seconds.
+
+With re-encoding:
+
+If you leave out the `-c copy` option, `ffmpeg` will automatically re-encode
+the output video and audio according to the format you chose. For high quality
+video and audio, read the [x264 Encoding Guide](https://ffmpeg.org/trac/ffmpeg/wiki/x264EncodingGuide)
+and the [AAC Encoding Guide](http://ffmpeg.org/trac/ffmpeg/wiki/AACEncodingGuide)
+, respectively.
+
+For example:
+
+```bash
+ffmpeg -ss [start] -i in.mp4 -t [duration] -c:v libx264 -c:a aac -strict
+experimental -b:a 128k out.mp4
+```
+
+## Mux video and audio from another video
+
+To copy the video from in0.mp4 and audio from in1.mp4:
+
+```bash
+ffmpeg -i in0.mp4 -i in1.mp4 -c copy -map 0:0 -map 1:1 -shortest out.mp4
+```
+
+- With [-c copy](http://ffmpeg.org/ffmpeg.html#Stream-copy) the streams will be
+  `stream copied`, not re-encoded, so there will be no quality loss. If you want
+  to re-encode, see [FFmpeg Wiki: H.264 Encoding Guide](https://trac.ffmpeg.org/wiki/Encode/H.264).
+- The `-shortest` option will cause the output duration to match the duration
+  of the shortest input stream.
+- See the
+  [`-map` option documentation](http://ffmpeg.org/ffmpeg.html#Advanced-options)
+  for more info.
+
+## Concat demuxer
+
+First, make a text file.
+
+```bash
+file 'in1.mp4'
+file 'in2.mp4'
+file 'in3.mp4'
+file 'in4.mp4'
+```
+
+Then, run `ffmpeg`:
+
+```bash
+ffmpeg -f concat -i list.txt -c copy out.mp4
+```
+
+## Delay audio/video
+
+Delay video by 3.84 seconds:
+
+```bash
+ffmpeg -i in.mp4 -itsoffset 3.84 -i in.mp4 -map 1:v -map 0:a -vcodec copy
+-acodec copy out.mp4
+```
+
+Delay audio by 3.84 seconds:
+
+```bash
+ffmpeg -i in.mp4 -itsoffset 3.84 -i in.mp4 -map 0:v -map 1:a -vcodec copy
+-acodec copy out.mp4
+```
+
+## Burn subtitles
+
+Use the [libass](http://ffmpeg.org/ffmpeg.html#ass) library (make sure your
+ffmpeg install has the library in the configuration `--enable-libass`).
+
+First convert the subtitles to .ass format:
+
+```bash
+ffmpeg -i sub.srt sub.ass
+```
+
+Then add them using a video filter:
+
+```bash
+ffmpeg -i in.mp4 -vf ass=sub.ass out.mp4
+```
+
+## Extract the frames from a video
+
+To extract all frames from between 1 and 5 seconds, and also between 11 and 15 seconds:
+
+```bash
+ffmpeg -i in.mp4 -vf select='between(t,1,5)+between(t,11,15)' -vsync 0 out%d.png
+```
+
+To extract one frame per second only:
+
+```bash
+ffmpeg -i in.mp4 -fps=1 -vsync 0 out%d.png
+```
+
+## Rotate a video
+
+Rotate 90 clockwise:
+
+```bash
+ffmpeg -i in.mov -vf "transpose=1" out.mov
+```
+
+For the transpose parameter you can pass:
+
+```bash
+0 = 90CounterCLockwise and Vertical Flip (default)
+1 = 90Clockwise
+2 = 90CounterClockwise
+3 = 90Clockwise and Vertical Flip
+```
+
+Use `-vf "transpose=2,transpose=2"` for 180 degrees.
+
+## Download "Transport Stream" video streams
+
+1. Loate the playlist file, e.g. using Chrome > F12 > Network > Filter: m3u8
+2. Download and concatenate the video fragments:
+
+```bash
+ffmpeg -i "path_to_playlist.m3u8" -c copy -bsf:a aac_adtstoasc out.mp4
+```
+
+If you get a "Protocol 'https not on whitelist 'file,crypto'!" error
+, add the `protocol_whitelist` option:
+
+```bash
+ffmpeg -protocol_whitelist "file,http,https,tcp,tls" -i "path_to_playlist.m3u8"
+-c copy -bsf:a aac_adtstoasc out.mp4
+```
+
+## Mute some of the audio
+
+To replace the first 90 seconds of audio with silence:
+
+```bash
+ffmpeg -i in.mp4 -vcodec copy -af "volume=enable='lte(t,90)':volume=0" out.mp4
+```
+
+To replace all audio between 1'20" and 1'30" with silence:
+
+```bash
+ffmpeg -i in.mp4 -vcodec copy -af "volume=enable='between(t,80,90)':volume=0" out.mp4
+```
+
+## Deinterlace
+
+Deinterlacing using "yet another deinterlacing filter".
+
+```bash
+ffmpeg -i in.mp4 -vf yadif out.mp4
+```
+
+## Create a video slideshow from images
+
+Parameters: `-r` marks the image framerate (inverse time of each image);
+`-vf fps=25` marks the true framerate of the output.
+
+```bash
+ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
+```
+
+## Extract images from a video
+
+- Extract all frames: `ffmpeg -i input.mp4 thumb%04d.jpg -hide_banner`
+- Extract a frame each second: `ffmpeg -i input.mp4 -vf fps=1 thumb%04d.jpg -hide_banner`
+- Extract only one frame: `ffmpeg -i input.mp4 -ss 00:00:10.000 -vframes 1 thumb.jpg`
+
+## Metadata: Change the title
+
+```bash
+ffmpeg -i in.mp4 -map_metadata -1 -metadata title="My Title" -c:v copy -c:a
+copy out.mp4
+```