diff --git a/docs/ffmpeg Notes.md b/docs/ffmpeg Notes.md index 9cd2786..cc38c1a 100644 --- a/docs/ffmpeg Notes.md +++ b/docs/ffmpeg Notes.md @@ -5,6 +5,7 @@ - [Get Test Image with ffmpeg](#get-test-image-with-ffmpeg) - [Batch-ify ffmpeg Command](#batch-ify-ffmpeg-command) - [Add Metadata to File](#add-metadata-to-file) +- [Create Slow-mo](#create-slow-mo) - [Transcode Profiles](#transcode-profiles) - [Original \[40.3 Mb/s\]](#original-403-mbs) - [Mediainfo](#mediainfo) @@ -59,6 +60,16 @@ This comment flag is visible in Windows file details. More information: [corbpie.com](https://write.corbpie.com/adding-metadata-to-a-video-or-audio-file-with-ffmpeg/). +# Create Slow-mo +Creating a slow-mo clip is a two-step process. This assumes your input is encoded with h264. + +1. Copy the video to a raw h264 bitstream: `ffmpeg -i "$input" -map 0:v -c:v copy -bsf:v h264_mp4toannexb 'raw.h264'` +2. Generate new timestamps for each frame with `genpts` (generate presentation timestamps): `ffmpeg -fflags +genpts -r 30 -i raw.h264 -c:v copy -movflags faststart "$output"`. The `-r 30` flag sets the new framerate to 30 frames per second. +3. Optionally, interpolate motion for the newly slowed video: `ffmpeg -i "$input" -filter:v "minterpolate='mi_mode=mci:mc_mode=aobmc:vsbmc=1:fps=60'" "$output"` + +Note that these slow-mo files will have no audio. + +If you need audio, or just more information, see the [ffmpeg docs](https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video) # Transcode Profiles ## Original [40.3 Mb/s]