Opened 4 years ago

Last modified 22 months ago

#3087 open defect

Suspicion that valid random access point is not marked as keyframe in AVCHD samples from Panasonic Lumix GH1 (1080i material)

Reported by: rmk Owned by:
Priority: normal Component: avcodec
Version: git-master Keywords: h264 bounty
Cc: Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

This is a follow-up to #3083.

The issue is very similar here, that I-frames that work as random access points (checked by cutting off the beginning of the file until the packet start of such a frame and it decodes fine) are not marked as keyframes by the parser.

The heuristic introduced to fix #3083

if(h->sps.ref_frame_count <= 1 && h->pps.ref_count[0] <= 1 && s->pict_type == AV_PICTURE_TYPE_I)

s->key_frame = 1;

fails here because both, h->sps.ref_frame_count and h->pps.ref_count[0] are 2.

I understand too little of h264 internals to say how that may be changed but maybe the heuristic does not cover the interlaced case.

I don't know if it has anything to do with it but this material is progressive segmented frame (i.e. progressively scanned but encoded as field pictures).

Attachments (1)

gh1_1080i_first2p5m.mts (2.4 MB) - added by rmk 4 years ago.

Change History (11)

Changed 4 years ago by rmk

comment:1 follow-up: Changed 4 years ago by cehoyos

Isn't this a duplicate of ticket #3063?

comment:2 Changed 4 years ago by cehoyos

  • Keywords h264 added
  • Version changed from unspecified to git-master

comment:3 in reply to: ↑ 1 ; follow-up: Changed 4 years ago by richardpl

Replying to cehoyos:

Isn't this a duplicate of ticket #3063?

You did not reply in timely manner to question in that ticket.....

comment:4 in reply to: ↑ 3 Changed 4 years ago by cehoyos

Replying to richardpl:

Replying to cehoyos:

Isn't this a duplicate of ticket #3063?

You did not reply in timely manner to question in that ticket.....

Which question?

comment:5 Changed 4 years ago by rmk

#3063 is fixed. The fix for it does not fix what's described here (see description). I asked whether I should open a new ticket for that case and now did so.

Your choice if you want to merge the two and reopen #3063. Both options are good for me.

comment:6 Changed 4 years ago by cehoyos

Could you confirm that ticket #3063 is fixed? Preferably there in the ticket?
Thanks.

comment:7 Changed 4 years ago by rmk

Ups, my bad. I mixed up the numbers. I thought you meant #3083. No, this is different, i.e. not a duplicate. In that case (#3063) the parser correctly marks the frames as key frames but the decoder does not and Michael's fix only affected the parser. It's also a different camera.

comment:8 Changed 4 years ago by cehoyos

  • Component changed from undetermined to avcodec

comment:9 Changed 22 months ago by rmk

I am offering a bounty of 200 Euro for a committed fix (I need an invoice though).

comment:10 Changed 22 months ago by richardpl

  • Keywords bounty added
  • Status changed from new to open
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