[FFmpeg-devel] [PATCH 2/3] avcodec/h264dec: Move ERContext to H264Context

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Thu Mar 24 22:21:50 EET 2022


Since 7be2d2a70cd20d88fd826a83f87037d14681a579 only one context
is used. Moving it to H264Context from H264SliceContext is natural.

One could access the ERContext from H264SliceContext
via H264SliceContext.h264->er; yet H264SliceContext.h264 should
naturally be const-qualified, because slice threads should not
modify the main context. The ERContext is an exception
to this, as ff_er_add_slice() is intended to be called simultaneously
by multiple threads. And for this one needs a pointer whose
pointed-to-type is not const-qualified.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavcodec/h264_slice.c | 31 ++++++---------
 libavcodec/h264dec.c    | 86 ++++++++++++++++++++---------------------
 libavcodec/h264dec.h    |  7 ++--
 3 files changed, 56 insertions(+), 68 deletions(-)

diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index f6104dde89..d56722a5c2 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -537,7 +537,7 @@ static int h264_frame_start(H264Context *h)
     h->cur_pic_ptr = pic;
     ff_h264_unref_picture(h, &h->cur_pic);
     if (CONFIG_ERROR_RESILIENCE) {
-        ff_h264_set_erpic(&h->slice_ctx[0].er.cur_pic, NULL);
+        ff_h264_set_erpic(&h->er.cur_pic, NULL);
     }
 
     if ((ret = ff_h264_ref_picture(h, &h->cur_pic, h->cur_pic_ptr)) < 0)
@@ -549,9 +549,9 @@ static int h264_frame_start(H264Context *h)
     }
 
     if (CONFIG_ERROR_RESILIENCE && h->enable_er) {
-        ff_er_frame_start(&h->slice_ctx[0].er);
-        ff_h264_set_erpic(&h->slice_ctx[0].er.last_pic, NULL);
-        ff_h264_set_erpic(&h->slice_ctx[0].er.next_pic, NULL);
+        ff_er_frame_start(&h->er);
+        ff_h264_set_erpic(&h->er.last_pic, NULL);
+        ff_h264_set_erpic(&h->er.next_pic, NULL);
     }
 
     for (i = 0; i < 16; i++) {
@@ -1004,11 +1004,7 @@ static int h264_slice_header_init(H264Context *h)
     ff_videodsp_init(&h->vdsp, sps->bit_depth_luma);
 
     if (!HAVE_THREADS || !(h->avctx->active_thread_type & FF_THREAD_SLICE)) {
-        ret = ff_h264_slice_context_init(h, &h->slice_ctx[0]);
-        if (ret < 0) {
-            av_log(h->avctx, AV_LOG_ERROR, "context_init() failed.\n");
-            goto fail;
-        }
+        ff_h264_slice_context_init(h, &h->slice_ctx[0]);
     } else {
         for (i = 0; i < h->nb_slice_ctx; i++) {
             H264SliceContext *sl = &h->slice_ctx[i];
@@ -1018,10 +1014,7 @@ static int h264_slice_header_init(H264Context *h)
             sl->mvd_table[0]       = h->mvd_table[0]       + i * 8 * 2 * h->mb_stride;
             sl->mvd_table[1]       = h->mvd_table[1]       + i * 8 * 2 * h->mb_stride;
 
-            if ((ret = ff_h264_slice_context_init(h, sl)) < 0) {
-                av_log(h->avctx, AV_LOG_ERROR, "context_init() failed.\n");
-                goto fail;
-            }
+            ff_h264_slice_context_init(h, sl);
         }
     }
 
@@ -2667,7 +2660,7 @@ static void decode_finish_row(const H264Context *h, H264SliceContext *sl)
 
     ff_h264_draw_horiz_band(h, sl, top, height);
 
-    if (h->droppable || sl->h264->slice_ctx[0].er.error_occurred)
+    if (h->droppable || h->er.error_occurred)
         return;
 
     ff_thread_report_progress(&h->cur_pic_ptr->tf, top + height - 1,
@@ -2682,9 +2675,7 @@ static void er_add_slice(H264SliceContext *sl,
         return;
 
     if (CONFIG_ERROR_RESILIENCE) {
-        ERContext *er = &sl->h264->slice_ctx[0].er;
-
-        ff_er_add_slice(er, startx, starty, endx, endy, status);
+        ff_er_add_slice(sl->er, startx, starty, endx, endy, status);
     }
 }
 
@@ -2713,13 +2704,13 @@ static int decode_slice(struct AVCodecContext *avctx, void *arg)
     sl->is_complex = FRAME_MBAFF(h) || h->picture_structure != PICT_FRAME ||
                      (CONFIG_GRAY && (h->flags & AV_CODEC_FLAG_GRAY));
 
-    if (!(h->avctx->active_thread_type & FF_THREAD_SLICE) && h->picture_structure == PICT_FRAME && h->slice_ctx[0].er.error_status_table) {
+    if (!(h->avctx->active_thread_type & FF_THREAD_SLICE) && h->picture_structure == PICT_FRAME && sl->er->error_status_table) {
         const int start_i  = av_clip(sl->resync_mb_x + sl->resync_mb_y * h->mb_width, 0, h->mb_num - 1);
         if (start_i) {
-            int prev_status = h->slice_ctx[0].er.error_status_table[h->slice_ctx[0].er.mb_index2xy[start_i - 1]];
+            int prev_status = sl->er->error_status_table[sl->er->mb_index2xy[start_i - 1]];
             prev_status &= ~ VP_START;
             if (prev_status != (ER_MV_END | ER_DC_END | ER_AC_END))
-                h->slice_ctx[0].er.error_occurred = 1;
+                sl->er->error_occurred = 1;
         }
     }
 
diff --git a/libavcodec/h264dec.c b/libavcodec/h264dec.c
index 2a510b0a01..f438376431 100644
--- a/libavcodec/h264dec.c
+++ b/libavcodec/h264dec.c
@@ -154,14 +154,16 @@ void ff_h264_free_tables(H264Context *h)
     av_buffer_pool_uninit(&h->motion_val_pool);
     av_buffer_pool_uninit(&h->ref_index_pool);
 
+#if CONFIG_ERROR_RESILIENCE
+    av_freep(&h->er.mb_index2xy);
+    av_freep(&h->er.error_status_table);
+    av_freep(&h->er.er_temp_buffer);
+    av_freep(&h->dc_val_base);
+#endif
+
     for (i = 0; i < h->nb_slice_ctx; i++) {
         H264SliceContext *sl = &h->slice_ctx[i];
 
-        av_freep(&sl->dc_val_base);
-        av_freep(&sl->er.mb_index2xy);
-        av_freep(&sl->er.error_status_table);
-        av_freep(&sl->er.er_temp_buffer);
-
         av_freep(&sl->bipred_scratchpad);
         av_freep(&sl->edge_emu_buffer);
         av_freep(&sl->top_borders[0]);
@@ -176,6 +178,7 @@ void ff_h264_free_tables(H264Context *h)
 
 int ff_h264_alloc_tables(H264Context *h)
 {
+    ERContext *const er = &h->er;
     const int big_mb_num = h->mb_stride * (h->mb_height + 1);
     const int row_mb_num = 2*h->mb_stride*FFMAX(h->nb_slice_ctx, 1);
     const int st_size = big_mb_num + h->mb_stride;
@@ -208,33 +211,11 @@ int ff_h264_alloc_tables(H264Context *h)
             h->mb2br_xy[mb_xy] = 8 * (FMO ? mb_xy : (mb_xy % (2 * h->mb_stride)));
         }
 
-    return 0;
-}
-
-/**
- * Init context
- * Allocate buffers which are not shared amongst multiple threads.
- */
-int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
-{
-    ERContext *er = &sl->er;
-    int mb_array_size = h->mb_height * h->mb_stride;
-    int y_size  = (2 * h->mb_width + 1) * (2 * h->mb_height + 1);
-    int c_size  = h->mb_stride * (h->mb_height + 1);
-    int yc_size = y_size + 2   * c_size;
-    int x, y, i;
-
-    sl->ref_cache[0][scan8[5]  + 1] =
-    sl->ref_cache[0][scan8[7]  + 1] =
-    sl->ref_cache[0][scan8[13] + 1] =
-    sl->ref_cache[1][scan8[5]  + 1] =
-    sl->ref_cache[1][scan8[7]  + 1] =
-    sl->ref_cache[1][scan8[13] + 1] = PART_NOT_AVAILABLE;
-
-    if (sl != h->slice_ctx) {
-        memset(er, 0, sizeof(*er));
-    } else if (CONFIG_ERROR_RESILIENCE) {
+    if (CONFIG_ERROR_RESILIENCE) {
         const int er_size = h->mb_height * h->mb_stride * (4*sizeof(int) + 1);
+        int mb_array_size = h->mb_height * h->mb_stride;
+        int y_size  = (2 * h->mb_width + 1) * (2 * h->mb_height + 1);
+        int yc_size = y_size + 2 * big_mb_num;
 
         /* init ER */
         er->avctx          = h->avctx;
@@ -252,7 +233,7 @@ int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
         if (!FF_ALLOCZ_TYPED_ARRAY(er->mb_index2xy,        h->mb_num + 1) ||
             !FF_ALLOCZ_TYPED_ARRAY(er->error_status_table, mb_array_size) ||
             !FF_ALLOCZ_TYPED_ARRAY(er->er_temp_buffer,     er_size)       ||
-            !FF_ALLOCZ_TYPED_ARRAY(sl->dc_val_base,        yc_size))
+            !FF_ALLOCZ_TYPED_ARRAY(h->dc_val_base,         yc_size))
             return AVERROR(ENOMEM); // ff_h264_free_tables will clean up for us
 
         for (y = 0; y < h->mb_height; y++)
@@ -261,16 +242,31 @@ int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
 
         er->mb_index2xy[h->mb_height * h->mb_width] = (h->mb_height - 1) *
                                                       h->mb_stride + h->mb_width;
-        er->dc_val[0] = sl->dc_val_base + h->mb_width * 2 + 2;
-        er->dc_val[1] = sl->dc_val_base + y_size + h->mb_stride + 1;
-        er->dc_val[2] = er->dc_val[1] + c_size;
-        for (i = 0; i < yc_size; i++)
-            sl->dc_val_base[i] = 1024;
+        er->dc_val[0] = h->dc_val_base + h->mb_width * 2 + 2;
+        er->dc_val[1] = h->dc_val_base + y_size + h->mb_stride + 1;
+        er->dc_val[2] = er->dc_val[1] + big_mb_num;
+        for (int i = 0; i < yc_size; i++)
+            h->dc_val_base[i] = 1024;
     }
 
     return 0;
 }
 
+/**
+ * Init slice context
+ */
+void ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
+{
+    sl->ref_cache[0][scan8[5]  + 1] =
+    sl->ref_cache[0][scan8[7]  + 1] =
+    sl->ref_cache[0][scan8[13] + 1] =
+    sl->ref_cache[1][scan8[5]  + 1] =
+    sl->ref_cache[1][scan8[7]  + 1] =
+    sl->ref_cache[1][scan8[13] + 1] = PART_NOT_AVAILABLE;
+
+    sl->er = &h->er;
+}
+
 static int h264_init_pic(H264Picture *pic)
 {
     pic->f = av_frame_alloc();
@@ -739,7 +735,7 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
         goto end;
 
     // set decode_error_flags to allow users to detect concealed decoding errors
-    if ((ret < 0 || h->slice_ctx->er.error_occurred) && h->cur_pic_ptr) {
+    if ((ret < 0 || h->er.error_occurred) && h->cur_pic_ptr) {
         h->cur_pic_ptr->f->decode_error_flags |= FF_DECODE_ERROR_DECODE_SLICES;
     }
 
@@ -764,25 +760,25 @@ end:
         H264SliceContext *sl = h->slice_ctx;
         int use_last_pic = h->last_pic_for_ec.f->buf[0] && !sl->ref_count[0];
 
-        ff_h264_set_erpic(&sl->er.cur_pic, h->cur_pic_ptr);
+        ff_h264_set_erpic(&h->er.cur_pic, h->cur_pic_ptr);
 
         if (use_last_pic) {
-            ff_h264_set_erpic(&sl->er.last_pic, &h->last_pic_for_ec);
+            ff_h264_set_erpic(&h->er.last_pic, &h->last_pic_for_ec);
             sl->ref_list[0][0].parent = &h->last_pic_for_ec;
             memcpy(sl->ref_list[0][0].data, h->last_pic_for_ec.f->data, sizeof(sl->ref_list[0][0].data));
             memcpy(sl->ref_list[0][0].linesize, h->last_pic_for_ec.f->linesize, sizeof(sl->ref_list[0][0].linesize));
             sl->ref_list[0][0].reference = h->last_pic_for_ec.reference;
         } else if (sl->ref_count[0]) {
-            ff_h264_set_erpic(&sl->er.last_pic, sl->ref_list[0][0].parent);
+            ff_h264_set_erpic(&h->er.last_pic, sl->ref_list[0][0].parent);
         } else
-            ff_h264_set_erpic(&sl->er.last_pic, NULL);
+            ff_h264_set_erpic(&h->er.last_pic, NULL);
 
         if (sl->ref_count[1])
-            ff_h264_set_erpic(&sl->er.next_pic, sl->ref_list[1][0].parent);
+            ff_h264_set_erpic(&h->er.next_pic, sl->ref_list[1][0].parent);
 
-        sl->er.ref_count = sl->ref_count[0];
+        h->er.ref_count = sl->ref_count[0];
 
-        ff_er_frame_end(&sl->er);
+        ff_er_frame_end(&h->er);
         if (use_last_pic)
             memset(&sl->ref_list[0][0], 0, sizeof(sl->ref_list[0][0]));
     }
diff --git a/libavcodec/h264dec.h b/libavcodec/h264dec.h
index 6ad2333419..0b9c5784a2 100644
--- a/libavcodec/h264dec.h
+++ b/libavcodec/h264dec.h
@@ -170,7 +170,7 @@ typedef struct H264Ref {
 typedef struct H264SliceContext {
     struct H264Context *h264;
     GetBitContext gb;
-    ERContext er;
+    ERContext *er;
 
     int slice_num;
     int slice_type;
@@ -271,7 +271,6 @@ typedef struct H264SliceContext {
     unsigned int pps_id;
 
     const uint8_t *intra_pcm_ptr;
-    int16_t *dc_val_base;
 
     uint8_t *bipred_scratchpad;
     uint8_t *edge_emu_buffer;
@@ -543,6 +542,8 @@ typedef struct H264Context {
     int height_from_caller;
 
     int enable_er;
+    ERContext er;
+    int16_t *dc_val_base;
 
     H264SEIContext sei;
 
@@ -784,7 +785,7 @@ int ff_h264_ref_picture(H264Context *h, H264Picture *dst, H264Picture *src);
 int ff_h264_replace_picture(H264Context *h, H264Picture *dst, const H264Picture *src);
 void ff_h264_unref_picture(H264Context *h, H264Picture *pic);
 
-int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl);
+void ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl);
 
 void ff_h264_draw_horiz_band(const H264Context *h, H264SliceContext *sl, int y, int height);
 
-- 
2.32.0



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