Opened 9 years ago

Closed 8 years ago

#920 closed defect (fixed)

Missing pocCRA update causes decoder assertion failure

Reported by: kiranmisra Owned by:
Priority: minor Milestone: HM-9.2
Component: HM Version: HM-9.1
Keywords: Cc: fbossen, ksuehring, davidf, jct-vc@…

Description

While testing HM-9.1 we discovered that the HM decoder encounters an assertion failure at line 600 in the TComSlice.cpp. The bitstream is valid however currently the value of variable pocCRA is not updated at the decoder when an IDR NALU type is encountered in the bitstream. The attached fix proposes a change that updates pocCRA when an IDR or IDR_N_LP NALU type is encountered.

Attachments (3)

Missing_pocCRA_update.cpp.patch (502 bytes) - added by kiranmisra 9 years ago.
Patch to update pocCRA for IDR
str.bin (59.6 KB) - added by kiranmisra 8 years ago.
str_hm_91_pocCRA_assertion_example.bin (59.6 KB) - added by kiranmisra 8 years ago.

Download all attachments as: .zip

Change History (10)

comment:1 Changed 9 years ago by DefaultCC Plugin

  • Cc fbossen ksuehring davidf jct-vc@… added

Changed 9 years ago by kiranmisra

Patch to update pocCRA for IDR

comment:2 Changed 9 years ago by ksuehring

Sounds like a bad name for something that is not the POC of a CRA access unit.

comment:3 Changed 8 years ago by fbossen

It would be helpful to have a corresponding bitstream to reproduce the error

Changed 8 years ago by kiranmisra

comment:4 Changed 8 years ago by kiranmisra

Attached is an example bitstream str.bin. It was created by concatenating a random access main bitstream with 50 frames and a low delay B main bitstream with 50 frames. The first bitstream has a pocCRA value of 32 which is never changed at the start of the second bitstreams IDR picture. As a result when within the second bitstream when POC 33 references pictures with POC lower than 32 it causes an assertion failure at the decoder. The proposed patch updates pocCRA when an IDR NALU type is encountered in the bitstream.

comment:5 Changed 8 years ago by fbossen

Thank you for the stream. Can you clarify which version of HM was used to generate it?

Changed 8 years ago by kiranmisra

comment:6 Changed 8 years ago by kiranmisra

Apologies, it seems the earlier uploaded example bitstream was generated using an experimental version of the source (HM-9.1 with bug fixes 712, 827). I have regenerated the bitstream using HM-9.1 source and uploaded it "str_hm_91_pocCRA_assertion_example.bin".

comment:7 Changed 8 years ago by fbossen

  • Milestone set to HM-9.2
  • Resolution set to fixed
  • Status changed from new to closed

Fixed in r3196

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  • David Flynn(Subscriber)
  • Frank Bossen(Subscriber, Participant)
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  • Karsten Suehring(Subscriber, Participant, Always)
  • Kiran Misra(Reporter, Participant)