avcodec/cbs_h265: add support for SPS Multilayer extension fields

Signed-off-by: James Almer <jamrial@gmail.com>

3 files changed, 55 insertions, 2 deletions

diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index 5ec781ddab..828e56b8c0 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -499,7 +499,8 @@ static int cbs_h2645_fragment_add_nals(CodedBitstreamContext *ctx,
         size_t size = nal->size;
         enum AVCodecID codec_id = ctx->codec->codec_id;
 
-        if (codec_id != AV_CODEC_ID_VVC && nal->nuh_layer_id > 0)
+        if (codec_id == AV_CODEC_ID_HEVC && nal->nuh_layer_id > 0 &&
+            (nal->type < HEVC_NAL_VPS || nal->type > HEVC_NAL_PPS))
             continue;
 
         // Remove trailing zeroes.
diff --git a/libavcodec/cbs_h265.h b/libavcodec/cbs_h265.h
index 91a5a55317..0f0541b2ef 100644
--- a/libavcodec/cbs_h265.h
+++ b/libavcodec/cbs_h265.h
@@ -248,12 +248,16 @@ typedef struct H265RawSPS {
     uint8_t sps_video_parameter_set_id;
 
     uint8_t sps_max_sub_layers_minus1;
+    uint8_t sps_ext_or_max_sub_layers_minus1;
     uint8_t sps_temporal_id_nesting_flag;
 
     H265RawProfileTierLevel profile_tier_level;
 
     uint8_t sps_seq_parameter_set_id;
 
+    uint8_t update_rep_format_flag;
+    uint8_t sps_rep_format_idx;
+
     uint8_t chroma_format_idc;
     uint8_t separate_colour_plane_flag;
 
@@ -284,6 +288,8 @@ typedef struct H265RawSPS {
     uint8_t max_transform_hierarchy_depth_intra;
 
     uint8_t scaling_list_enabled_flag;
+    uint8_t sps_infer_scaling_list_flag;
+    uint8_t sps_scaling_list_ref_layer_id;
     uint8_t sps_scaling_list_data_present_flag;
     H265RawScalingList scaling_list;
 
@@ -342,6 +348,9 @@ typedef struct H265RawSPS {
 
     uint8_t motion_vector_resolution_control_idc;
     uint8_t intra_boundary_filtering_disable_flag;
+
+    // Multilayer extension.
+    uint8_t inter_view_mv_vert_constraint_flag;
 } H265RawSPS;
 
 typedef struct H265RawPPS {
diff --git a/libavcodec/cbs_h265_syntax_template.c b/libavcodec/cbs_h265_syntax_template.c
index c6db439b3b..c2f13288b8 100644
--- a/libavcodec/cbs_h265_syntax_template.c
+++ b/libavcodec/cbs_h265_syntax_template.c
@@ -747,6 +747,16 @@ static int FUNC(sps_scc_extension)(CodedBitstreamContext *ctx, RWContext *rw,
     return 0;
 }
 
+static int FUNC(sps_multilayer_extension)(CodedBitstreamContext *ctx, RWContext *rw,
+                                          H265RawSPS *current)
+{
+    int err;
+
+    flag(inter_view_mv_vert_constraint_flag);
+
+    return 0;
+}
+
 static int FUNC(vui_parameters_default)(CodedBitstreamContext *ctx,
                                         RWContext *rw, H265RawVUI *current,
                                         H265RawSPS *sps)
@@ -781,6 +791,7 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
     int err, i;
     unsigned int min_cb_log2_size_y, ctb_log2_size_y,
                  min_cb_size_y,   min_tb_log2_size_y;
+    unsigned int multi_layer_ext_sps_flag;
 
     HEADER("Sequence Parameter Set");
 
@@ -794,7 +805,17 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
         return AVERROR_INVALIDDATA;
     }
 
+    if (current->nal_unit_header.nuh_layer_id == 0)
     u(3, sps_max_sub_layers_minus1, 0, vps->vps_max_sub_layers_minus1);
+    else {
+        u(3, sps_ext_or_max_sub_layers_minus1, 0, HEVC_MAX_SUB_LAYERS);
+        infer(sps_max_sub_layers_minus1, current->sps_ext_or_max_sub_layers_minus1 == HEVC_MAX_SUB_LAYERS
+                                         ? vps->vps_max_sub_layers_minus1
+                                         : current->sps_ext_or_max_sub_layers_minus1);
+    }
+    multi_layer_ext_sps_flag = current->nal_unit_header.nuh_layer_id &&
+                               current->sps_ext_or_max_sub_layers_minus1 == HEVC_MAX_SUB_LAYERS;
+    if (!multi_layer_ext_sps_flag) {
     flag(sps_temporal_id_nesting_flag);
 
     if (vps->vps_temporal_id_nesting_flag &&
@@ -814,9 +835,20 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
 
     CHECK(FUNC(profile_tier_level)(ctx, rw, &current->profile_tier_level,
                                    1, current->sps_max_sub_layers_minus1));
+    } else {
+        if (current->sps_max_sub_layers_minus1 > 0)
+            infer(sps_temporal_id_nesting_flag, vps->vps_temporal_id_nesting_flag);
+        else
+            infer(sps_temporal_id_nesting_flag, 1);
+    }
 
     ue(sps_seq_parameter_set_id, 0, 15);
 
+    if (multi_layer_ext_sps_flag) {
+        flag(update_rep_format_flag);
+        if (current->update_rep_format_flag)
+            ub(8, sps_rep_format_idx);
+    } else {
     ue(chroma_format_idc, 0, 3);
     if (current->chroma_format_idc == 3)
         flag(separate_colour_plane_flag);
@@ -841,9 +873,11 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
 
     ue(bit_depth_luma_minus8,   0, 8);
     ue(bit_depth_chroma_minus8, 0, 8);
+    }
 
     ue(log2_max_pic_order_cnt_lsb_minus4, 0, 12);
 
+    if (!multi_layer_ext_sps_flag) {
     flag(sps_sub_layer_ordering_info_present_flag);
     for (i = (current->sps_sub_layer_ordering_info_present_flag ?
               0 : current->sps_max_sub_layers_minus1);
@@ -865,6 +899,7 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
                   current->sps_max_latency_increase_plus1[current->sps_max_sub_layers_minus1]);
         }
     }
+    }
 
     ue(log2_min_luma_coding_block_size_minus3,   0, 3);
     min_cb_log2_size_y = current->log2_min_luma_coding_block_size_minus3 + 3;
@@ -895,9 +930,17 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
 
     flag(scaling_list_enabled_flag);
     if (current->scaling_list_enabled_flag) {
+        if (multi_layer_ext_sps_flag)
+            flag(sps_infer_scaling_list_flag);
+        else
+            infer(sps_infer_scaling_list_flag, 0);
+        if (current->sps_infer_scaling_list_flag)
+            ub(6, sps_scaling_list_ref_layer_id);
+        else {
         flag(sps_scaling_list_data_present_flag);
         if (current->sps_scaling_list_data_present_flag)
             CHECK(FUNC(scaling_list_data)(ctx, rw, &current->scaling_list));
+        }
     } else {
         infer(sps_scaling_list_data_present_flag, 0);
     }
@@ -955,7 +998,7 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
     if (current->sps_range_extension_flag)
         CHECK(FUNC(sps_range_extension)(ctx, rw, current));
     if (current->sps_multilayer_extension_flag)
-        return AVERROR_PATCHWELCOME;
+        CHECK(FUNC(sps_multilayer_extension)(ctx, rw, current));
     if (current->sps_3d_extension_flag)
         return AVERROR_PATCHWELCOME;
     if (current->sps_scc_extension_flag)