So certain high-profile individuals were complaining that it was
difficult to configure recording settings for quality in OBS. So, I
decided to add a very easy-to-use auto-configuration for high quality
encoding -- including lossless encoding. This feature will
automatically configure ideal recording settings based upon a specified
quality level.
Recording quality presets added to simple output:
- Same as stream: Copies the encoded streaming data with no extra usage
hit.
- High quality: uses a higher CRF value (starting at 23) if using x264.
- Indistinguishable quality: uses a low CRF value (starting at 16) if
using x264.
- Lossless will spawn an FFmpeg output that uses huffyuv encoding. If a
user tries to select lossless, they will be warned both via a dialog
prompt and a warning message in the settings window to ensure they
understand that it requires tremendous amounts of free space. It will
always use the AVI file format.
Extra Notes:
- When High/Indistinguishable quality is set, it will allow you to
select the recording encoder. Currently, it just allows you to select
x264 (at either veryfast or ultrafast). Later on, it'll be useful to
be able to set up pre-configured presets for hardware encoders once
more are implemented and tested.
- I decided to allow the use of x264 at both veryfast or ultrafast
presets. The reasoning is two-fold:
1.) ultrafast is perfectly viable even for near indistinguishable
quality as long as it has the appropriate CRF value. It's nice if you
want to record but would like to or need to reduce the impact of
encoding on the CPU. It will automatically compensate for the preset at
the cost of larger file size.
2.) It was suggested to just always use ultrafast, but ultrafast
requires 2-4x as much disk space for the same CRF (most likely due to
x264 compensating for the preset). Providing veryfast is important if
you really want to reduce file size and/or reduce blocking at lower
quality levels.
- When a recording preset is used, a secondary audio encoder is also
spawned at 192 bitrate to ensure high quality audio. I chose 192
because that's the limit of the media foundation aac encoder on
windows, which I want to make sure is used if available due to its
high performance.
- The CRF calculation is based upon resolution, quality, and whether
it's set to ultrafast. First, quality sets the base CRF, 23 for
"good" quality, 16 for "very high" quality. If set to ultrafast,
it'll subtract 2 points from the CRF value to help compensate. Lower
resolutions will also lower the CRF value to help improve higher
details with a smaller pixel ratio.