[FFmpeg-devel] [PATCH] cbs_h266: add range extension support
Frank Plowman
post at frankplowman.com
Wed Jul 5 15:50:29 EEST 2023
On 05/07/2023 13:38, Frank Plowman wrote:
> On 05/07/2023 12:45, James Almer wrote:
>> On 7/5/2023 8:38 AM, Nuo Mi wrote:
>>> From: frankplow <post at frankplowman.com>
>>>
>>> ---
>>> libavcodec/cbs_h266.h | 18 ++++++
>>> libavcodec/cbs_h266_syntax_template.c | 79
>>> +++++++++++++++++++++++++--
>>> 2 files changed, 93 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/libavcodec/cbs_h266.h b/libavcodec/cbs_h266.h
>>> index e33d08a0f5..40aba9eb13 100644
>>> --- a/libavcodec/cbs_h266.h
>>> +++ b/libavcodec/cbs_h266.h
>>> @@ -120,6 +120,13 @@ typedef struct H266GeneralConstraintsInfo {
>>> uint8_t gci_no_virtual_boundaries_constraint_flag;
>>> uint8_t gci_num_reserved_bits;
>>> uint8_t gci_reserved_zero_bit[255];
>>> +
>>> + uint8_t gci_all_rap_pictures_constraint_flag;
>>> + uint8_t gci_no_extended_precision_processing_constraint_flag;
>>> + uint8_t gci_no_ts_residual_coding_rice_constraint_flag;
>>> + uint8_t gci_no_rrc_rice_extension_constraint_flag;
>>> + uint8_t gci_no_persistent_rice_adaptation_constraint_flag;
>>> + uint8_t gci_no_reverse_last_sig_coeff_constraint_flag;
>>> } H266GeneralConstraintsInfo;
>>> typedef struct H266RawProfileTierLevel {
>>> @@ -451,6 +458,15 @@ typedef struct H266RawSPS {
>>> uint8_t sps_extension_flag;
>>> + uint8_t sps_range_extension_flag;
>>> + uint8_t sps_extension_7bits;
>>> +
>>> + uint8_t sps_extended_precision_flag;
>>> + uint8_t sps_ts_residual_coding_rice_present_in_sh_flag;
>>> + uint8_t sps_rrc_rice_extension_flag;
>>> + uint8_t sps_persistent_rice_adaptation_enabled_flag;
>>> + uint8_t sps_reverse_last_sig_coeff_enabled_flag;
>>> +
>>> H266RawExtensionData extension_data;
>>> } H266RawSPS;
>>> @@ -734,6 +750,8 @@ typedef struct H266RawSliceHeader {
>>> uint8_t sh_sign_data_hiding_used_flag;
>>> uint8_t sh_ts_residual_coding_disabled_flag;
>>> + uint8_t sh_ts_residual_coding_rice_idx_minus1;
>>> + uint8_t sh_reverse_last_sig_coeff_flag;
>>> uint16_t sh_slice_header_extension_length;
>>> uint8_t sh_slice_header_extension_data_byte[256];
>>> diff --git a/libavcodec/cbs_h266_syntax_template.c
>>> b/libavcodec/cbs_h266_syntax_template.c
>>> index 485c02f590..893fa55369 100644
>>> --- a/libavcodec/cbs_h266_syntax_template.c
>>> +++ b/libavcodec/cbs_h266_syntax_template.c
>>> @@ -61,7 +61,7 @@ static int FUNC(general_constraints_info)
>>> (CodedBitstreamContext *ctx,
>>> RWContext *rw,
>>> H266GeneralConstraintsInfo *current)
>>> {
>>> - int err, i;
>>> + int err, i, num_additional_bits_used;
>>> flag(gci_present_flag);
>>> if (current->gci_present_flag) {
>>> @@ -149,7 +149,25 @@ static int FUNC(general_constraints_info)
>>> (CodedBitstreamContext *ctx,
>>> flag(gci_no_ladf_constraint_flag);
>>> flag(gci_no_virtual_boundaries_constraint_flag);
>>> ub(8, gci_num_reserved_bits);
>>
>> This should be renamed to gci_num_additional_bits while at it.
>>
>>> - for (i = 0; i < current->gci_num_reserved_bits; i++) {
>>> + if (current->gci_num_reserved_bits > 5) {
>>> + flag(gci_all_rap_pictures_constraint_flag);
>>> + flag(gci_no_extended_precision_processing_constraint_flag);
>>> + flag(gci_no_ts_residual_coding_rice_constraint_flag);
>>> + flag(gci_no_rrc_rice_extension_constraint_flag);
>>> + flag(gci_no_persistent_rice_adaptation_constraint_flag);
>>> + flag(gci_no_reverse_last_sig_coeff_constraint_flag);
>>> + num_additional_bits_used = 6;
>>> + } else {
>>> + infer(gci_all_rap_pictures_constraint_flag, 0);
>>> + infer(gci_no_extended_precision_processing_constraint_flag, 0);
>>> + infer(gci_no_ts_residual_coding_rice_constraint_flag, 0);
>>> + infer(gci_no_rrc_rice_extension_constraint_flag, 0);
>>> + infer(gci_no_persistent_rice_adaptation_constraint_flag, 0);
>>> + infer(gci_no_reverse_last_sig_coeff_constraint_flag, 0);
>>> + num_additional_bits_used = 0;
>>> + }
>>> +
>>> + for (i = 0; i < current->gci_num_reserved_bits -
>>> num_additional_bits_used; i++) {
>>> flags(gci_reserved_zero_bit[i], 1, i);
>>> }
>>> }
>>> @@ -963,6 +981,23 @@ static int FUNC(vps) (CodedBitstreamContext
>>> *ctx, RWContext *rw,
>>> return 0;
>>> }
>>> +static int FUNC(sps_range_extension)(CodedBitstreamContext *ctx,
>>> RWContext *rw,
>>> + H266RawSPS *current)
>>> +{
>>> + int err;
>>> +
>>> + flag(sps_extended_precision_flag);
>>> + if (current->sps_transform_skip_enabled_flag) {
>>> + flag(sps_ts_residual_coding_rice_present_in_sh_flag);
>>> + } else {
>>> + infer(sps_ts_residual_coding_rice_present_in_sh_flag, 0);
>>> + }
>>> + flag(sps_rrc_rice_extension_flag);
>>> + flag(sps_persistent_rice_adaptation_enabled_flag);
>>> + flag(sps_reverse_last_sig_coeff_enabled_flag);
>>> +
>>> + return 0;
>>> +}
>>> static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
>>> H266RawSPS *current)
>>> @@ -1518,9 +1553,33 @@ static int FUNC(sps)(CodedBitstreamContext
>>> *ctx, RWContext *rw,
>>> } else {
>>> CHECK(FUNC(vui_parameters_default) (ctx, rw, ¤t->vui));
>>> }
>>> +
>>> flag(sps_extension_flag);
>>> - if (current->sps_extension_flag)
>>> - CHECK(FUNC(extension_data) (ctx, rw,
>>> ¤t->extension_data));
>>> + if (current->sps_extension_flag) {
>>> + flag(sps_range_extension_flag);
>>> + ub(7, sps_extension_7bits);
>>> +
>>> + if (current->sps_range_extension_flag) {
>>> + CHECK(FUNC(sps_range_extension)(ctx, rw, current));
>>> + } else {
>>> + infer(sps_extended_precision_flag, 0);
>>> + infer(sps_ts_residual_coding_rice_present_in_sh_flag, 0);
>>> + infer(sps_rrc_rice_extension_flag, 0);
>>> + infer(sps_persistent_rice_adaptation_enabled_flag, 0);
>>> + infer(sps_reverse_last_sig_coeff_enabled_flag, 0);
>>> + }
>>> + } else {
>>> + infer(sps_range_extension_flag, 0);
>>> + infer(sps_extension_7bits, 0);
>>> + infer(sps_extended_precision_flag, 0);
>>> + infer(sps_ts_residual_coding_rice_present_in_sh_flag, 0);
>>> + infer(sps_rrc_rice_extension_flag, 0);
>>> + infer(sps_persistent_rice_adaptation_enabled_flag, 0);
>>> + infer(sps_reverse_last_sig_coeff_enabled_flag, 0);
>>> + }
>>> +
>>> + if (current->sps_extension_7bits)
>>> + CHECK(FUNC(extension_data)(ctx, rw,
>>> ¤t->extension_data));
>>> CHECK(FUNC(rbsp_trailing_bits) (ctx, rw));
>>> @@ -3005,6 +3064,18 @@ static int FUNC(slice_header)
>>> (CodedBitstreamContext *ctx, RWContext *rw,
>>> flag(sh_ts_residual_coding_disabled_flag);
>>> else
>>> infer(sh_ts_residual_coding_disabled_flag, 0);
>>> +
>>> + if (!current->sh_ts_residual_coding_disabled_flag &&
>>> + sps->sps_ts_residual_coding_rice_present_in_sh_flag)
>>> + ub(3, sh_ts_residual_coding_rice_idx_minus1);
>>> + else
>>> + infer(sh_ts_residual_coding_rice_idx_minus1, 0);
>>> +
>>> + if (sps->sps_reverse_last_sig_coeff_enabled_flag)
>>> + flag(sh_reverse_last_sig_coeff_flag);
>>> + else
>>> + infer(sh_reverse_last_sig_coeff_flag, 0);
>>
>> Do you know what sample if any in the conformance suite covers this?
>
> A matrix showing which test bitstreams test which range extension
> features is available here:
> https://github.com/ffvvc/FFmpeg/issues/83#issuecomment-1575658232
Apologies, I see now this is in the slice header rather than the SPS.
This particular logic is tested by the following bitstreams:
* 12b444vvc1_E_Sony_2
* 12b444Ietsrc_A_Kwai_2
* 10b444P16_D_Sony_2
* 12b444Iepp_A_Sharp_2
* 12b444SPetsrc_B_Kwai_2
* 10b444P16_A_Sony_2
* 12b444vvc1_D_Sony_2
* 10b444P16_C_Sony_2
* 12b444vvc1_A_Sony_2
* 10b444P12_C_Sony_2
* 12b444SPvvc1_A_Alibaba_2
* 12b420SPvvc1_A_KDDI_2
* 12b444SPetsrc_H_Kwai_2
* 10b444P12_A_Sony_2
* 12b444SPepp_A_Sharp_2
* 12b444SPetsrc_D_Kwai_2
* 12b444SPetsrc_F_Kwai_2
* 10b444P16_E_Sony_2
* 12b444Ivvc1_A_Alibaba_2
* 12b444vvc1_B_Sony_2
* 10b444P16_B_Sony_2
* 12b420Ivvc1_A_InterDigital_2
* 10b444P12_E_Sony_2
* 12b444vvc1_C_Sony_2
* 12b420vvc1_A_Alibaba_2
* 12b444SPetsrc_A_Kwai_2
* 12b444SPetsrc_C_Kwai_2
* 12b444SPetsrc_E_Kwai_2
* 12b444SPetsrc_G_Kwai_2
* HRD_A_Fujitsu_4
* 12b444etsrc_A_Kwai_2
* 10b444P12_B_Sony_2
* 12b444epp_A_Sharp_2
* 10b444P12_D_Sony_2
>
>>
>>> +
>>> if (pps->pps_slice_header_extension_present_flag) {
>>> ue(sh_slice_header_extension_length, 0, 256);
>>> for (i = 0; i < current->sh_slice_header_extension_length;
>>> i++)
>> _______________________________________________
>> ffmpeg-devel mailing list
>> ffmpeg-devel at ffmpeg.org
>> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>>
>> To unsubscribe, visit link above, or email
>> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
>
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
More information about the ffmpeg-devel
mailing list