[FFmpeg-devel] [PATCH 2/8] cbs_h265: Use helper macro for maximum values of fixed-width elements

[Mark Thompson]

On 12/03/18 00:41, Jun Zhao wrote:
> On 2018/3/12 2:30, Mark Thompson wrote:
>> Apply the same logic as the previous patch to H.265.  There are no cases
>> which currently overflow here, but this is still more consistent.
>> ---
>>  libavcodec/cbs_h265_syntax_template.c | 16 ++++++++--------
>>  1 file changed, 8 insertions(+), 8 deletions(-)
>>
>> diff --git a/libavcodec/cbs_h265_syntax_template.c b/libavcodec/cbs_h265_syntax_template.c
>> index dae7f2dd46..140c827c9d 100644
>> --- a/libavcodec/cbs_h265_syntax_template.c
>> +++ b/libavcodec/cbs_h265_syntax_template.c
>> @@ -665,7 +665,7 @@ static int FUNC(sps_scc_extension)(CodedBitstreamContext *ctx, RWContext *rw,
>>                                            : current->bit_depth_chroma_minus8 + 8;
>>                  for (i = 0; i <= current->sps_num_palette_predictor_initializer_minus1; i++)
>>                      u(bit_depth, sps_palette_predictor_initializers[comp][i],
>> -                      0, (1 << bit_depth) - 1);
>> +                      0, MAX_UINT_BITS(bit_depth));
>>              }
>>          }
>>      }
>> @@ -827,7 +827,7 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
>>          for (i = 0; i < current->num_long_term_ref_pics_sps; i++) {
>>              u(current->log2_max_pic_order_cnt_lsb_minus4 + 4,
>>                lt_ref_pic_poc_lsb_sps[i],
>> -              0, (1 << (current->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1);
>> +              0, MAX_UINT_BITS(current->log2_max_pic_order_cnt_lsb_minus4 + 4));
>>              flag(used_by_curr_pic_lt_sps_flag[i]);
>>          }
>>      }
>> @@ -845,7 +845,7 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
>>          flag(sps_multilayer_extension_flag);
>>          flag(sps_3d_extension_flag);
>>          flag(sps_scc_extension_flag);
>> -        u(4, sps_extension_4bits, 0, (1 << 4) - 1);
>> +        u(4, sps_extension_4bits, 0, MAX_UINT_BITS(4));
>>      }
>>  
>>      if (current->sps_range_extension_flag)
>> @@ -925,7 +925,7 @@ static int FUNC(pps_scc_extension)(CodedBitstreamContext *ctx, RWContext *rw,
>>                                            : current->chroma_bit_depth_entry_minus8 + 8;
>>                  for (i = 0; i < current->pps_num_palette_predictor_initializer; i++)
>>                      u(bit_depth, pps_palette_predictor_initializers[comp][i],
>> -                      0, (1 << bit_depth) - 1);
>> +                      0, MAX_UINT_BITS(bit_depth));
>>              }
>>          }
>>      }
>> @@ -1038,7 +1038,7 @@ static int FUNC(pps)(CodedBitstreamContext *ctx, RWContext *rw,
>>          flag(pps_multilayer_extension_flag);
>>          flag(pps_3d_extension_flag);
>>          flag(pps_scc_extension_flag);
>> -        u(4, pps_extension_4bits, 0, (1 << 4) - 1);
>> +        u(4, pps_extension_4bits, 0, MAX_UINT_BITS(4));
>>      }
>>      if (current->pps_range_extension_flag)
>>          CHECK(FUNC(pps_range_extension)(ctx, rw, current));
>> @@ -1274,7 +1274,7 @@ static int FUNC(slice_segment_header)(CodedBitstreamContext *ctx, RWContext *rw,
>>              const H265RawSTRefPicSet *rps;
>>  
>>              u(sps->log2_max_pic_order_cnt_lsb_minus4 + 4, slice_pic_order_cnt_lsb,
>> -              0, (1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1);
>> +              0, MAX_UINT_BITS(sps->log2_max_pic_order_cnt_lsb_minus4 + 4));
>>  
>>              flag(short_term_ref_pic_set_sps_flag);
>>              if (!current->short_term_ref_pic_set_sps_flag) {
>> @@ -1321,7 +1321,7 @@ static int FUNC(slice_segment_header)(CodedBitstreamContext *ctx, RWContext *rw,
>>                              ++num_pic_total_curr;
>>                      } else {
>>                          u(sps->log2_max_pic_order_cnt_lsb_minus4 + 4, poc_lsb_lt[i],
>> -                          0, (1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1);
>> +                          0, MAX_UINT_BITS(sps->log2_max_pic_order_cnt_lsb_minus4 + 4));
>>                          flag(used_by_curr_pic_lt_flag[i]);
>>                          if (current->used_by_curr_pic_lt_flag[i])
>>                              ++num_pic_total_curr;
>> @@ -1487,7 +1487,7 @@ static int FUNC(slice_segment_header)(CodedBitstreamContext *ctx, RWContext *rw,
>>              ue(offset_len_minus1, 0, 31);
>>              for (i = 0; i < current->num_entry_point_offsets; i++)
>>                  u(current->offset_len_minus1 + 1, entry_point_offset_minus1[i],
>> -                  0, (1 << (current->offset_len_minus1 + 1)) - 1);
>> +                  0, MAX_UINT_BITS(current->offset_len_minus1 + 1));
>>          }
>>      }
>>  
> Other thing about cbs_265, now cbs_264 can support SEI, but cbs_265 not,
> is it will support SEI in cbs_265?

It's on my list of stuff which should be done at some point, but not a priority due to lack of any immediate use-case.  Do you have some reason for wanting it?

- Mark