green color blocks

[styst]

Hello, when using heif-convert for image conversion, I have noticed occasional occurrences of green color blocks appearing in the image after multiple conversions of the same picture.

[bradh]

Can you confirm this is with x265 and de265?

Can you share the exact commands, along with source data to reproduce this?

It is likely in the de265 layer, but would be good to check first.

[styst]

command：heif-convert a.heic a.jpg
This issue occurs on any .heic image as long as the conversion command is executed consecutively, and it will occasionally result in an image with a green color block.

[farindk]

This looks very much like a race-condition when multiple tiles are decoded in parallel.
I could not reproduce this yet.

Can you tell me exactly which version (or commit hash) you are using and which cmake settings? Especially ENABLE_MULTITHREADING_SUPPORT and ENABLE_PARALLEL_TILE_DECODING.

[farindk]

Also let me know the system (Linux, Windows, macOS).

[styst]

commit:08aba4a02ab491667b0fd71ccba109b26908b6f4

system:Debian GNU/Linux

I used this to install it：
https://github.com/MaestroError/heif-converter-image/blob/maestro/install-libheif.sh

repetition step：

[farindk]

Ok, I managed to reproduce this. Does not happen very often with my 4 core CPU. Might be that it happens more often with more cores.

[styst]

Our server has 2 core CPU. Is there any way to avoid this kind of problem

[styst]

Setting the container to a single core resolved this issue for me. Thank you.

[farindk]

Can you please confirm that the above commit fixes the race condition when running on multiple cores?

[styst]

After verification, it has been confirmed that the above commit no longer encounters race condition issues when running on multiple cores

[farindk]

Thank you for the report and the confirmation that it is fixed now.