avcodec/h2645: allocate film grain metadata dynamically

Film grain support adds a huge amount of overhead to the H264Context
structure for a feature that is rarely used. On low end devices or
pages that have lots of media this bloats memory usage rapidly.

This changes the static film grain metadata allocations to be dynamic
which reduces the H264Context size from 851808 bytes to 53444 bytes.

Bug: https://crbug.com/359358875
Signed-off-by: Dale Curtis <dalecurtis@chromium.org>
Signed-off-by: Niklas Haas <git@haasn.dev>

libavcodec/h2645_sei.c

@@ -245,7 +245,12 @@ static int decode_registered_user_data(H2645SEI *h, GetByteContext *gb,
 
         provider_oriented_code = bytestream2_get_byteu(gb);
         if (provider_oriented_code == aom_grain_provider_oriented_code) {
-            return ff_aom_parse_film_grain_sets(&h->aom_film_grain,
+            if (!h->aom_film_grain) {
+                h->aom_film_grain = av_mallocz(sizeof(*h->aom_film_grain));
+                if (!h->aom_film_grain)
+                    return AVERROR(ENOMEM);
+            }
+            return ff_aom_parse_film_grain_sets(h->aom_film_grain,
                                                 gb->buffer,
                                                 bytestream2_get_bytes_left(gb));
         }
@@ -494,7 +499,12 @@ int ff_h2645_sei_message_decode(H2645SEI *h, enum SEIType type,
     case SEI_TYPE_DISPLAY_ORIENTATION:
         return decode_display_orientation(&h->display_orientation, gb);
     case SEI_TYPE_FILM_GRAIN_CHARACTERISTICS:
-        return decode_film_grain_characteristics(&h->film_grain_characteristics, codec_id, gb);
+        if (!h->film_grain_characteristics) {
+            h->film_grain_characteristics = av_mallocz(sizeof(*h->film_grain_characteristics));
+            if (!h->film_grain_characteristics)
+                return AVERROR(ENOMEM);
+        }
+        return decode_film_grain_characteristics(h->film_grain_characteristics, codec_id, gb);
     case SEI_TYPE_FRAME_PACKING_ARRANGEMENT:
         return decode_frame_packing_arrangement(&h->frame_packing, gb, codec_id);
     case SEI_TYPE_ALTERNATIVE_TRANSFER_CHARACTERISTICS:
@@ -811,8 +821,8 @@ int ff_h2645_sei_to_frame(AVFrame *frame, H2645SEI *sei,
             return ret;
     }
 
-    if (sei->film_grain_characteristics.present) {
+    if (sei->film_grain_characteristics && sei->film_grain_characteristics->present) {
-        H2645SEIFilmGrainCharacteristics *fgc = &sei->film_grain_characteristics;
+        H2645SEIFilmGrainCharacteristics *fgc = sei->film_grain_characteristics;
         AVFilmGrainParams *fgp = av_film_grain_params_create_side_data(frame);
         AVFilmGrainH274Params *h274;
 
@@ -884,9 +894,11 @@ FF_ENABLE_DEPRECATION_WARNINGS
     }
 
 #if CONFIG_HEVC_SEI
-    ret = ff_aom_attach_film_grain_sets(&sei->aom_film_grain, frame);
+    if (sei->aom_film_grain) {
-    if (ret < 0)
+        ret = ff_aom_attach_film_grain_sets(sei->aom_film_grain, frame);
-        return ret;
+        if (ret < 0)
+            return ret;
+    }
 #endif
 
     return 0;
@@ -913,5 +925,7 @@ void ff_h2645_sei_reset(H2645SEI *s)
     s->ambient_viewing_environment.present = 0;
     s->mastering_display.present = 0;
     s->content_light.present = 0;
-    s->aom_film_grain.enable = 0;
+
+    av_freep(&s->film_grain_characteristics);
+    av_freep(&s->aom_film_grain);
 }

libavcodec/h2645_sei.h

@@ -135,11 +135,13 @@ typedef struct H2645SEI {
     H2645SEIFramePacking frame_packing;
     H2645SEIDisplayOrientation display_orientation;
     H2645SEIAlternativeTransfer alternative_transfer;
-    H2645SEIFilmGrainCharacteristics film_grain_characteristics;
     H2645SEIAmbientViewingEnvironment ambient_viewing_environment;
     H2645SEIMasteringDisplay mastering_display;
     H2645SEIContentLight content_light;
-    AVFilmGrainAFGS1Params aom_film_grain;
+
+    // Dynamic allocations due to large size.
+    H2645SEIFilmGrainCharacteristics* film_grain_characteristics;
+    AVFilmGrainAFGS1Params* aom_film_grain;
 } H2645SEI;
 
 enum {

libavcodec/h264_picture.c

@@ -27,6 +27,7 @@
 
 #include "libavutil/avassert.h"
 #include "libavutil/emms.h"
+#include "libavutil/mem.h"
 #include "error_resilience.h"
 #include "avcodec.h"
 #include "h264dec.h"
@@ -212,9 +213,15 @@ int ff_h264_field_end(H264Context *h, H264SliceContext *sl, int in_setup)
         const AVFrameSideData *sd = av_frame_get_side_data(cur->f, AV_FRAME_DATA_FILM_GRAIN_PARAMS);
 
         err = AVERROR_INVALIDDATA;
-        if (sd) // a decoding error may have happened before the side data could be allocated
+        if (sd) { // a decoding error may have happened before the side data could be allocated
-            err = ff_h274_apply_film_grain(cur->f_grain, cur->f, &h->h274db,
+            if (!h->h274db) {
+                h->h274db = av_mallocz(sizeof(*h->h274db));
+                if (!h->h274db)
+                    return AVERROR(ENOMEM);
+            }
+            err = ff_h274_apply_film_grain(cur->f_grain, cur->f, h->h274db,
                                            (AVFilmGrainParams *) sd->data);
+        }
         if (err < 0) {
             av_log(h->avctx, AV_LOG_WARNING, "Failed synthesizing film "
                    "grain, ignoring: %s\n", av_err2str(err));

libavcodec/h264_sei.c

@@ -55,7 +55,6 @@ void ff_h264_sei_uninit(H264SEIContext *h)
     h->picture_timing.present      = 0;
     h->buffering_period.present    = 0;
     h->common.frame_packing.present       = 0;
-    h->common.film_grain_characteristics.present = 0;
     h->common.display_orientation.present = 0;
     h->common.afd.present                 =  0;
 

libavcodec/h264_slice.c

@@ -516,7 +516,10 @@ static int h264_frame_start(H264Context *h)
     pic->f->crop_top    = h->crop_top;
     pic->f->crop_bottom = h->crop_bottom;
 
-    pic->needs_fg = h->sei.common.film_grain_characteristics.present && !h->avctx->hwaccel &&
+    pic->needs_fg =
+        h->sei.common.film_grain_characteristics &&
+        h->sei.common.film_grain_characteristics->present &&
+        !h->avctx->hwaccel &&
         !(h->avctx->export_side_data & AV_CODEC_EXPORT_DATA_FILM_GRAIN);
 
     if ((ret = alloc_picture(h, pic)) < 0)

libavcodec/h264dec.c

@@ -156,6 +156,8 @@ void ff_h264_free_tables(H264Context *h)
     av_freep(&h->mb2b_xy);
     av_freep(&h->mb2br_xy);
 
+    av_freep(&h->h274db);
+
     ff_refstruct_pool_uninit(&h->qscale_table_pool);
     ff_refstruct_pool_uninit(&h->mb_type_pool);
     ff_refstruct_pool_uninit(&h->motion_val_pool);

libavcodec/h264dec.h

@@ -344,7 +344,7 @@ typedef struct H264Context {
     H264DSPContext h264dsp;
     H264ChromaContext h264chroma;
     H264QpelContext h264qpel;
-    H274FilmGrainDatabase h274db;
+    H274FilmGrainDatabase* h274db;  // Dyanmic allocation due to large size.
 
     H264Picture DPB[H264_MAX_PICTURE_COUNT];
     H264Picture *cur_pic_ptr;

libavcodec/hevc/hevcdec.c

@@ -412,8 +412,8 @@ static int export_stream_params_from_sei(HEVCContext *s)
         avctx->color_trc = s->sei.common.alternative_transfer.preferred_transfer_characteristics;
     }
 
-    if (s->sei.common.film_grain_characteristics.present ||
+    if ((s->sei.common.film_grain_characteristics && s->sei.common.film_grain_characteristics->present) ||
-        s->sei.common.aom_film_grain.enable)
+        (s->sei.common.aom_film_grain && s->sei.common.aom_film_grain->enable))
         avctx->properties |= FF_CODEC_PROPERTY_FILM_GRAIN;
 
     return 0;
@@ -3267,8 +3267,8 @@ static int hevc_frame_start(HEVCContext *s, HEVCLayerContext *l,
     else
         s->cur_frame->f->flags &= ~AV_FRAME_FLAG_KEY;
 
-    s->cur_frame->needs_fg = (s->sei.common.film_grain_characteristics.present ||
+    s->cur_frame->needs_fg = ((s->sei.common.film_grain_characteristics && s->sei.common.film_grain_characteristics->present) ||
-                              s->sei.common.aom_film_grain.enable) &&
+                              (s->sei.common.aom_film_grain && s->sei.common.aom_film_grain->enable)) &&
         !(s->avctx->export_side_data & AV_CODEC_EXPORT_DATA_FILM_GRAIN) &&
         !s->avctx->hwaccel;
 
@@ -3277,8 +3277,8 @@ static int hevc_frame_start(HEVCContext *s, HEVCLayerContext *l,
         goto fail;
 
     if (s->cur_frame->needs_fg &&
-        (s->sei.common.film_grain_characteristics.present &&
+        (s->sei.common.film_grain_characteristics && s->sei.common.film_grain_characteristics->present &&
-         !ff_h274_film_grain_params_supported(s->sei.common.film_grain_characteristics.model_id,
+         !ff_h274_film_grain_params_supported(s->sei.common.film_grain_characteristics->model_id,
                                               s->cur_frame->f->format) ||
          !av_film_grain_params_select(s->cur_frame->f))) {
         av_log_once(s->avctx, AV_LOG_WARNING, AV_LOG_DEBUG, &s->film_grain_warning_shown,
@@ -3415,8 +3415,13 @@ static int hevc_frame_end(HEVCContext *s, HEVCLayerContext *l)
             av_assert0(0);
             return AVERROR_BUG;
         case AV_FILM_GRAIN_PARAMS_H274:
+            if (!s->h274db) {
+                s->h274db = av_mallocz(sizeof(*s->h274db));
+                if (!s->h274db)
+                    return AVERROR(ENOMEM);
+            }
             ret = ff_h274_apply_film_grain(out->frame_grain, out->f,
-                                           &s->h274db, fgp);
+                                           s->h274db, fgp);
             break;
         case AV_FILM_GRAIN_PARAMS_AV1:
             ret = ff_aom_apply_film_grain(out->frame_grain, out->f, fgp);
@@ -3844,6 +3849,7 @@ static av_cold int hevc_decode_free(AVCodecContext *avctx)
     av_buffer_unref(&s->rpu_buf);
 
     av_freep(&s->md5_ctx);
+    av_freep(&s->h274db);
 
     ff_container_fifo_free(&s->output_fifo);
 

libavcodec/hevc/hevcdec.h

@@ -531,7 +531,7 @@ typedef struct HEVCContext {
     HEVCDSPContext hevcdsp;
     VideoDSPContext vdsp;
     BswapDSPContext bdsp;
-    H274FilmGrainDatabase h274db;
+    H274FilmGrainDatabase* h274db;  // Dynamically allocated due to large size.
 
     /** used on BE to byteswap the lines for checksumming */
     uint8_t *checksum_buf;