Bugs in BPSEI and PTSEI

[kazui]

1) Signalling of bp_max_sublayers_minus1 in BPSEI

Signalling of bp_max_sublayers_minus1 is unconditional both in the text and SEIReader::xReadSEIPictureTiming(). However, it is conditioned the value of cpb_removal_delay_deltas_present_flag in SEIWriter::xWriteSEIBufferingPeriod().

The following two lines in SEIWriter::xWriteSEIBufferingPeriod() should be moved from inside the if-statement " if (sei.m_cpbRemovalDelayDeltasPresentFlag) {..}" to before signalling bp_cpb_cnt_minus1.

CHECK (sei.m_bpMaxSubLayers < 1, "bp_max_sub_layers_minus1 must be > 0");

WRITE_CODE( sei.m_bpMaxSubLayers - 1, 3, "bp_max_sub_layers_minus1" );

2) For-loop for pt_du_common_cpb_removal_delay_increment_minus1[i] and pt_du_cpb_removal_delay_increment_minus1[i][j] in PTSEI

The end-value of the for-loops for pt_du_common_cpb_removal_delay_increment_minus1[i] (in SEIWriter::xWriteSEIPictureTiming() and SEIReader::xParseSEIPictureTiming()) does not match those in the text.

" for( int i = temporalId; i < bp.m_bpMaxSubLayers - 1; i ++ ) " shall be " for( int i = temporalId; i <= bp.m_bpMaxSubLayers - 1; i ++ ) ".

Similar modification shall also be applied to pt_du_cpb_removal_delay_increment_minus1[i][j].

3) Initialization of pt_sublayer_delays_present_flag[ 0 ] when bp_max_sublayers_minus1 is equal to 0 in PTSEI

The value of pt_sublayer_delays_present_flag[ bp_max_sublayers_minus1 ] is set to 1 in the text. It is asserted that this Initialization should be applied also to the case bp_max_sublayers_minus1 equal to 0.

However, pt_sublayer_delays_present_flag[ 0 ] is not initialized to 1 when bp_max_sublayers_minus1 is equal to 0 both in SEIWriter::xWriteSEIPictureTiming() and SEIReader::xParseSEIPictureTiming().

MR is in preparation.

[kazui]

Diff file is attached, instead of issuing MR.

[XiangLi]

Fixed in ​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/-/merge_requests/1857