3D SBSL and ABL option removed so MPV treats everything as HALF SBS/TAB not FULL SBS/TAB

mpv Information

Every major MPV release for the last few years

Other Information

- Windows version: Windows 10 and 11
- GPU model, driver and version: Nvidia 30,40 and 50 series
- Source of mpv: Zhonfly, Schinchiro and every other release
- Latest known working version: Years ago.
- Issue started after the following happened: Half SBS 3D

Reproduction Steps

SBSL (Full SBS) and ABL (Full TAB) have always been part of the ffmpeg stereo3D. But they was removed from MPV a few major versions back. I tried settings stereo-in=no but there is no stereo-out option and the logs (see below) suggest the "output" is still being sent as as Half SBS.
I'm not sure if the logs show the output as being interpreted as SBS2L which is half SBSL or A=None means that it is doing nothing. My only option to stop this behavior to to remove the 3D SBS tag from the MKV header file. The same applies for ABL as well as SBSR and ABR for right eyes first.

Expected Behavior

PS C:\Users\Admin> mpv --vf=format:stereo-in=help
Valid values for option stereo-in are:
no
mono
sbsl <-- This is what I think is needed
sbs2l
abl <-- This is what I think is needed
ab2r
ab2l
checkr
checkl
irr
irl
icr
icl
arcc
sbs2r
agmc
al
ar

Actual Behavior

PS C:\Users\Admin> mpv --vf=format:stereo-in=help
Valid values for option stereo-in are:
no
mono
---> no sbsl
sbs2l
---> no abl
ab2r
ab2l
checkr
checkl
irr
irl
icr
icl
arcc
sbs2r
agmc
al
ar

Log File

mpv.log

Selected entried below.
[ 4.135][d][mkv] | + StereoMode: sbs2l
...
[ 4.249][v][vf] [in] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 stereo=sbs2l A=none
[ 4.249][v][vf] [userdeint] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 stereo=sbs2l A=none
[ 4.249][v][vf] [userdeint] (disabled)
[ 4.249][v][vf] [format] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 stereo=sbs2l A=none
[ 4.249][v][vf] [autovflip] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 A=none
[ 4.249][v][vf] [autovflip] (disabled)
[ 4.249][v][vf] [autorotate] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 A=none
[ 4.249][v][vf] [autorotate] (disabled)
[ 4.249][v][vf] [convert] 3840x1080 d3d11[nv12] bt.709/bt.709/bt.1886/limited/display CL=mpeg2/4/h264 crop=3840x1080+0+0 A=none

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested and confirmed that the issue exists with the latest release version or newer.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

Start with the format filter's stereo-in option, using mpv --vf=format:stereo-in=help, and compare the available values with the reported ffmpeg stereo3D modes. Review the attached log, especially the MKV StereoMode and filter-chain entries. Done means determining whether full SBS/TAB and right-eye-first modes can be supported and verifying the resulting recognized options and output behavior.