signbias bits are ignored/reset/zeroed if error_resilience is set.

[GoogleCodeExporter]

I don't think this behaviour makes sense, since the signbias bits are coded in 
the same frame, so I have no idea why they would in any way be involved in 
past-independence setup checks.

The code in question is in 
vp9/common/vp9_entropymode.c:vp9_setup_past_independence()

  vp9_zero(cm->ref_frame_sign_bias);

and is called from vp9_decodeframe.c:read_uncompressed_header()

  if (frame_is_intra_only(cm) || cm->error_resilient_mode)
    vp9_setup_past_independence(cm);

I think that code (that zeroes ref_frame_sign_bias in 
vp9_setup_past_independence()) should be deleted in vp10.

Original issue reported on code.google.com by rsbul...@gmail.com on 4 Jun 2015 at 11:15

[GoogleCodeExporter]

Note that this also means that compound referencing is not ever enabled when 
error_resilience is set, since that requires non-zero sign bias bits.

Original comment by rsbul...@gmail.com on 4 Jun 2015 at 11:46

[GoogleCodeExporter]

Original comment by fgalli...@google.com on 18 Jun 2015 at 10:08

• Changed state: Available

[GoogleCodeExporter]

Original comment by ya...@google.com on 10 Jul 2015 at 11:10

• Added labels: Hotlist-VP10-must-fix

[GoogleCodeExporter]

Original comment by ya...@google.com on 14 Jul 2015 at 4:42

• Added labels: Type-Enhancement
• Removed labels: Type-Bug

[GoogleCodeExporter]

Original comment by ya...@google.com on 12 Aug 2015 at 10:06

• Changed state: Assigned