Desync with speed 0 and 1

[ycho]

Tested with commit: acb7b69

./target/release/rav1e ~/Downloads/crowd_run_2160p50.y4m -o test.ivf -r test_rec.y4m --quantizer 128 --speed=1 --limit=3 --low_latency --tune=Psnr

../aom_build/aomdec test.ivf -o test_dec.y4m -v
../aom_build/aomdec test.ivf --rawvideo -o test_dec.yuv -v
ffmpeg -i test_rec.y4m test_rec.yuv -v 0
cmp test_rec.yuv test_dec.yuv

test_rec.yuv test_dec.yuv differ: char 8324073, line 1
==> difference in 2nd frame

Similar desync with speed 0. 1st frame is fine.
Checked that it first happens at the 2nd frame both 1st and 2nd frame when two frames are encoded, and does. not happen if only one frame is encoded.
Speed 2, 6 and 10 were fine.

[shssoichiro]

Could you give it a test at speed 2? I'd like to see if this is likely related to bottom-up encoding.

[ycho]

Oh- Yeap, I missed stating that it was fine with speed 2!

[ycho]

If I try narrowing down, it happens inter frame & bottom-up partition search.

[ycho]

@shssoichiro
It is possible "--tune Psnr" is causing desync for speed 0 and 1 (i.e. bottomup partition).
I tried:
./target/release/rav1e ~/Downloads/crowd_run_2160p50.y4m -o test.ivf -r test_rec.y4m --quantizer 128 --speed=1 --limit=2
, then it is fine.

And I tried again:
./target/release/rav1e ~/Downloads/crowd_run_2160p50.y4m -o test.ivf -r test_rec.y4m --quantizer 128 --speed=1 --limit=2 --tune Psnr
, then desync happens.

test_rec.yuv test_dec.yuv differ: char 8418299, line 1

[barrbrain]

As far as I can tell, the desync occurs where 4x4 blocks are chosen. If I increase min_block_size to BlockSize::BLOCK_8X8 keeping all other settings, then it is fine.

[ycho]

I am trying with tx_domain_distortion off now (its default is on, and used with --tune Psnr), which I suspect.

[ycho]

I am trying with tx_domain_distortion off now (its default is on, and used with --tune Psnr), which I suspect.

There is still a desync, though different pixels are affected.

[ycho]

I tried with smaller input and 2x2 tiles, and there is also desync. Hence the issue is not specific to 4K but speed 0 or 1 with --tune Psnr.

./target/release/rav1e ~/sequences/objective-1-fast/KristenAndSara_1280x720_60f.y4m -o test.ivf -r test_rec.y4m --quantizer 128 --speed=1 --limit=2 --tile-rows=2 --tile-cols=2 -v --low-latency --tune Psnr

desync occur at 2nd frame
%cmp
test_rec.yuv test_dec.yuv differ: char 925782, line 4

[ycho]

Faster test:
./target/release/rav1e nyan.y4m -o test.ivf -r test_rec.y4m --quantizer 150 --speed=1 --limit=2 --low_latency --tune=Psnr

gives a desync!

[ycho]

And if I do this, it fixes for speed 1 but speed 0 still has desync.

  //dist_scale: [1.0, lambda / lambda_u, lambda / lambda_v],
  dist_scale: [1.0, 1.0, 1.0],

i.e. if not use dist_scale[].