Video encoded with 4:2:2 chroma subsampling doesn't load and then freezes application every time I try to CloseMedia()

[benwager]

Describe the issue I have a video which doesn't load and then freezes the application every time try to close it. I get a ReadyToPlayEvent, a MetaDataReadyEvent and then a ResolutionChanged event and then it gets no further.

The application doesn't actually freeze until I try to CloseMedia() or destroy the GameObject.

Your Setup (please complete the following information):

• Unity version: 2020.1.16f1
• AVPro Video version: 2.1.5 Ultra Edition
• Operating system version: Win 10
• Device model:
• Video specs (resolution, frame-rate, codec, file size):

`General Complete name : C:\Users...\testvid.mp4 Format : MPEG-4 Format profile : Base Media Codec ID : isom (isom/iso2/avc1/mp41) File size : 12.9 MiB Duration : 7 s 8 ms Overall bit rate : 15.5 Mb/s Writing application : Lavf57.83.100

Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High 4:2:[email protected] Format settings : CABAC / 4 Ref Frames Format settings, CABAC : Yes Format settings, Reference frames : 4 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 7 s 8 ms Bit rate : 15.5 Mb/s Width : 3 840 pixels Height : 2 160 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 29.970 (29970/1000) FPS Color space : YUV Chroma subsampling : 4:2:2 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.062 Stream size : 12.9 MiB (100%) Writing library : x264 core 152 r19 ba24899 Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=36 / lookahead_threads=6 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=30.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00 Language : English Codec configuration box : avcC

Other ID : 2 Type : Time code Format : QuickTime TC Duration : 7 s 8 ms Frame rate : 29.970 (29970/1000) FPS Time code of first frame : 00:00:00:00 Time code, striped : Yes Language : English Default : No `

[kahnivore]

Hey @benwager

Do you think you could send a copy of your video to [email protected] with the subject line #829 for testing?

Thanks

[benwager]

Yes, I have just sent it. Thanks

[kahnivore]

Hi @benwager

Seems like a hardware/media issue. Reproduced the freeze not only when trying to close the media, but even just trying to play it. Re-encoded with a chroma subsampling profile of 4:2:0 (from 4:2:2) and that fixed it. Obviously the freeze is less than ideal so will look into this further, but wanted to provide a fix in the meantime.

[AndrewRH]

I think we have an issue on this already - basically h.264 videos with certain specs (like 4:2:2 or 4:4:4) cause this behaviour of not displaying, and then freezing on closing.

[kahnivore]

Yeah it's #759 - it just doesn't mention 4:2:2, only 4:4:4. Summary of the issue here.

[benwager]

Is there some programmatic means of preventing the crash in the mean time, while you work on a long term solution?

[kahnivore]

We don't currently have a way to prevent the crash. Unfortunately the crash is a result of a bug in the Media Foundation/H.264 decoder which we can't do anything about. To prevent a crash you'd need to implement a way to pre-process the files to check if they are this format and avoid playing them if they are. We are planning to implement a way to do this in the future (i.e. to easily retrieve this type of info), but in the meantime you could use something like Media Info's API to do this.