Ticket #1048 (closed defect: fixed)

Opened 2 years ago

Last modified 2 years ago

Packed bitstream results in inaccurate seeking

Reported by: Plorkyeran Owned by: TheFluff
Priority: normal Milestone: 2.1.8
Component: Video Version: devel
Severity: major Keywords:
Cc: Platform: All
Sub Component: VProvider - FFMS

Description (last modified by Plorkyeran) (diff)

With VFW video generated with packed bitstream enabled and then muxed into matroska, different methods of seeking can produce different images for the same frame number when using FFMS2. With the attached script and  this video:

  1. Use ctrl-2 to jump to the end of the only subtitle line in the file
  2. Seek to the next frame. Note that it is frame 5151 and the titlecard remains visible.
  3. Framestep forward at least 10 frames to clear frame 5151 from the cache.
  4. Jump directly to frame 5151. Note that it is no longer the title card.

Jumping to frame 5150 via Jump to and then framestepping produces identical results.

Attachments

vfrexample.ass Download (726 bytes) - added by Plorkyeran 2 years ago.

Change History

comment:1 Changed 2 years ago by TheFluff

  • Owner set to TheFluff
  • Status changed from new to accepted

Mine.

Changed 2 years ago by Plorkyeran

comment:2 Changed 2 years ago by TheFluff

  • Status changed from accepted to closed
  • Resolution set to invalid

Not a bug in Aegisub, same thing happens with FFMS2 regardless of application. Most likely related to this FFMS bug:  http://code.google.com/p/ffmpegsource/issues/detail?id=3

One workaround is to use an AVI and the AVS provider.

comment:3 Changed 2 years ago by verm

  • Status changed from closed to reopened
  • Resolution invalid deleted
  • Description modified (diff)

Re-open this until it's fixed upstream or we fix it in Aegisub.

comment:4 Changed 2 years ago by Plorkyeran

  • Keywords vfr removed
  • Summary changed from VFR video is not frame-accurate to Packed bitstream results in inaccurate seeking
  • Description modified (diff)
  • Sub Component set to AProvider - FFMS

comment:5 Changed 2 years ago by Plorkyeran

  • Sub Component changed from AProvider - FFMS to VProvider - FFMS

comment:6 Changed 2 years ago by thefluff

  • Status changed from reopened to closed
  • Resolution set to fixed

(In [3820]) Update ffms2 to r238. Fixes #1048. This version is API and ABI compatible with the previous one so no further modifications are necessary.

comment:7 Changed 2 years ago by thefluff

(In [3821]) Merge r3820 into 2.1.8. Updates #1048.

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