video reader variable frame rate video false postitive

Dear DALI Team,

I think the variable frame rate check inside the video reader produces false positives. I attach two files that are generated from the same .h264 stream, via:

ffmpeg -r 25 -i raw.h264 -t 10 -c copy 25.mp4
ffmpeg -r 40 -i raw.h264 -t 10 -c copy 40.mp4

Both can be checked for vfr via ffmpeg:

$ `ffmpeg -i 25.mp4 -vf vfrdet -an -f null -
[...]
[Parsed_vfrdet_0 @ 0x56230ecf0d40] VFR:0.000000 (0/249)

$ ffmpeg -i 40.mp4 -vf vfrdet -an -f null -
[...]
[Parsed_vfrdet_0 @ 0x55f17728de80] VFR:0.000000 (0/399)

Which indicates that both are free of vfr stuff. Yet, the 25 fps video works fine, but the 40 fps video produces:

Error when constructing operator: readers__Video encountered:
[/opt/dali/dali/operators/reader/loader/video_loader.cc:382] Assert on "skip_vfr_check_ || almost_equal(av_q2d(file.frame_base_), pkt.duration * av_q2d(file.stream_base_), 2)" failed: Variable frame rate videos are unsupported. Check failed for file: /bla/bla/blub/40.mp4

The two video files in question can be found here:
https://drive.google.com/drive/folders/1qPCO_vUAVwO4C-6kOFqGlDMmyXfhKsud?usp=sharing

Start with the reported reproduction commands and the two linked MP4 files, then inspect the variable-frame-rate assertion at dali/operators/reader/loader/video_loader.cc:382. Compare the metadata used by the reader for 25.mp4 and 40.mp4 with the ffmpeg vfrdet output; done means the valid 40 fps file no longer produces a false variable-frame-rate failure.