warning: first frame is no keyframe

[jinbiao9504]

Summary of the bug:

I found an issue with VC-1 video:
When i seek to a position after playing a VC-1 video, a warning which says 'warning: first frame is no keyframe' is presented.
And the picture will be shortly not clear after seek. I think this is caused by the warinng.
The log and one of the VC-1 files about this issue is attached, is that an issue of ffplay?

How to reproduce:

ffplay 36_vc1_720x480_interlaced_advanced.m2ts
put down RIGHT key to seek

ffmpeg version:lastest

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

[jinbiao9504]

I am sorry that I cannot upload a media file bigger than 2.5M

[Balling]

Cannot reproduce.

[jinbiao9504]

Hi Balling,
Thank you for your reply!
You cannot reproduce because the movie attached is too short to seek.
Is that a way(e.g. email or others) i can upload the whole movie(about 20M) to you.
I can only upload attachment less than 2.5M here.

[Balling]

You can just upload to ​https://streams.videolan.org/upload/ (click on FFmpeg, of course).

[jinbiao9504]

The whole vc1 file has been uploaded

[jinbiao9504]

Hi Balling，have you received my movie file？

[mkver]

Your files are ​here.

[Balling]

Same happens on a blu-ray I have of "Whiteout".

I did mention it here: ​https://trac.ffmpeg.org/ticket/8515#comment:3

[jinbiao9504]

Replying to Balling:

Same happens on a blu-ray I have of "Whiteout".

I did mention it here: ​https://trac.ffmpeg.org/ticket/8515#comment:3

Yes, I saw many keyframe flags.
The decode-function may be affected if the player find the wrong keyframe after seek?

[Balling]

Will just again point out that this can be only reproduced on bigger file here ​https://streams.videolan.org/ffmpeg/incoming/9863/36_vc1_720x480_interlaced_advanced.m2ts

[Balling]

Okay, so I tried testing this after remux to mkv...

When i seek to a position after playing a VC-1 video, a warning which says 'warning: first frame is no keyframe' is presented.

The part about AFTER does not happen anymore. During video yes

put down RIGHT key to seek

This does not happen after end of video. Just pushing right button to seek does not cause issues, it gets stuck. But it does print warnings, also in mkv if you seek back it can suddely start saying

[vc1 @ 0000017742f2c740] Luma scaling is not supported, expect wrong picture
[vc1 @ 0000017742f2c740] Chroma scaling is not supported, expect wrong picture

and this happens even with -threads 1