Support forum for DG Tools

I have a issue with videos with high number of bframes and dgdecodenv.

SW decoders such as L-SMASH-Works decode it perfectly, while dgdecodenv gives corrupted output without any warning.

If I recall well, some previous version DGIndexNV gave error when trying to open videos with high bframes number.

Here is the sample

https://pixeldrain.com/u/JSsdkdnu

Increasing the number of DPB frames from 16 to 20 solves this. Yes, it's about the number of B frames. There is a lot of discussion on the internet about this. I'll make a slipstream today or tomorrow for that. Can't do it straightaway as there are some other things in the pipeline not quite done.

Formally, I should check if 20 exceeds the limit for the specified AVC level. If so I could bail out with illegal stream. But there's no problem handling a DPB of 20, so need to get school-marmish, especially when the SW players are fine with it. Increasing it increases the GPU memory requirements but we're well out of the GTX 8800 era.

Rocky wrote: ↑

Fri Oct 20, 2023 12:18 pm

Formally, I should check if 20 exceeds the limit for the specified AVC level.

Isn't there a HW limitation to number of B-Frames? I saw there is for encoding, don't know about decoding.

Please test this 64-bit build:

https://rationalqm.us/misc/Guest 2.zip

The NVDec decode sample uses DPB size 20, so there can't be any applicable limitation there.

This does decode correctly but I want you to test it too and let me know if you see any regressions. The HEVC parsing was totally revamped per code from Sherman . The HEVC parsing is now done by our code and not NVDec. That is needed for linux log file support.

Rocky wrote: ↑

Fri Oct 20, 2023 8:23 pm

Please test this 64-bit build

Works fine, thank you!

Rocky wrote: ↑

Fri Oct 20, 2023 8:23 pm

let me know if you see any regressions

Nothing that I can notice.

Rocky wrote: ↑

Fri Oct 20, 2023 8:23 pm

The HEVC parsing was totally revamped per code from Sherman

Thank you Sherman! The AVC parsing is ok?

Thank you for your testing.

Only HEVC parsing was affected because we already used our own code for AVC/MPEG/VC1, rather than NVDec parsing.