txs 0.0.1

Wrapper around ffmpeg and mpv that generates x264 test encodes and compares them

txs (test x264 settings) is a command line tool that can generate different combinations of x264 settings and make short test encodings with ffmpeg. It also comes with a Lua script for mpv that allows you to visually compare the test encodes and find the best one based on quality, estimated file size and estimated encoding time. It looks like this:

This is the output of txs tutorial:

This is a tutorial that should get you started. Run txs -h and txs SUB-COMMAND -h for more information.

$ txs -s source.mkv -r 25:00 10 -x crf=19:me=umh samples \
  -xs aq-strength=0.5/1.0:aq-mode=2/3:no-deblock

The above command creates test encodes or samples with all possible combinations of the given values for "aq-strength", "aq-mode" and "no-deblock" in the directory "samples.source@25:00-10.aq-strength:aq-mode:no-deblock". The samples are all encoded with "crf=19:me=umh", they are all 10 seconds long and start at 25 minutes in source.mkv:

source.sample@25:00-10.crf=19:me=umh:aq-strength=0.5:aq-mode=2.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=0.5:aq-mode=2:no-deblock.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=0.5:aq-mode=3.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=0.5:aq-mode=3:no-deblock.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=1.0:aq-mode=2.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=1.0:aq-mode=2:no-deblock.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=1.0:aq-mode=3.mkv
source.sample@25:00-10.crf=19:me=umh:aq-strength=1.0:aq-mode=3:no-deblock.mkv

You can provide multiple sets of sample settings to limit the number of combinations:

$ txs -s source.mkv -r 25:00 10 -x crf=19:me=umh samples \
  -xs aq-strength=0.5/1.0 aq-mode=2/3

This creates the following samples:

source.sample@25:00-10:crf=19:me=umh:aq-mode=2.mkv
source.sample@25:00-10:crf=19:me=umh:aq-mode=3.mkv
source.sample@25:00-10:crf=19:me=umh:aq-strength=0.5.mkv
source.sample@25:00-10:crf=19:me=umh:aq-strength=1.0.mkv

To compare encodes, use the "compare" subcommand:

$ txs -s source.mkv compare ./samples:orig@25:00-1.aq-strength:aq-mode

This opens mpv in fullscreen mode with a playlist of samples. You can adjust the playlist size with the -p (--playlist-size) option. Switch between samples with "j" and "k". If you seek to a different time, it is preserved. (You can even switch while playing a sample.) You can also switch to the original source with "o", although seek time preservation doesn't work very well in that case.

If one sample is the best in the current playlist, press "b" to unload all other samples and fill the playlist again. The best sample is kept in the playlist.

If one sample is the worst in the current playlist, press "w" to unload that sample. No more samples will be added to the playlist unless there is only one sample left. "Shift+w" does the same thing as "w", but it also removes the sample from the file system.

If all samples in the current playlist are equal, press "e" to stash them. The playlist is filled with new samples. Once you have seen all samples at least once, previously stashed samples are loaded again.

You can show/hide the playlist with "`".