h264: eliminate ff_h264_set_parameter_from_sps()

That function currently does two things -- reinitializing the DSP
contexts and setting low_delay based on the SPS values.

The former more appropriately belongs in h264_slice_header_init(), while
the latter only really makes sense in decode_slice_header().

The third call to ff_h264_set_parameter_from_sps(), done immediately
after parsing a new SPS, appears to serve no useful purpose, so it is
just dropped.

Also, drop now unneeded H264Context.cur_chroma_format_idc.

libavcodec/h264.c

@@ -570,7 +570,6 @@ static int h264_init_context(AVCodecContext *avctx, H264Context *h)
 
     h->avctx                 = avctx;
     h->dequant_coeff_pps     = -1;
-    h->cur_chroma_format_idc = -1;
 
     h->picture_structure     = PICT_FRAME;
     h->slice_context_count   = 1;
@@ -1175,44 +1174,6 @@ int ff_h264_get_profile(SPS *sps)
     return profile;
 }
 
-int ff_h264_set_parameter_from_sps(H264Context *h)
-{
-    if (h->flags & CODEC_FLAG_LOW_DELAY ||
-        (h->sps.bitstream_restriction_flag &&
-         !h->sps.num_reorder_frames)) {
-        if (h->avctx->has_b_frames > 1 || h->delayed_pic[0])
-            av_log(h->avctx, AV_LOG_WARNING, "Delayed frames seen. "
-                   "Reenabling low delay requires a codec flush.\n");
-        else
-            h->low_delay = 1;
-    }
-
-    if (h->avctx->has_b_frames < 2)
-        h->avctx->has_b_frames = !h->low_delay;
-
-    if (h->avctx->bits_per_raw_sample != h->sps.bit_depth_luma ||
-        h->cur_chroma_format_idc      != h->sps.chroma_format_idc) {
-        if (h->sps.bit_depth_luma >= 8 && h->sps.bit_depth_luma <= 10) {
-            h->avctx->bits_per_raw_sample = h->sps.bit_depth_luma;
-            h->cur_chroma_format_idc      = h->sps.chroma_format_idc;
-            h->pixel_shift                = h->sps.bit_depth_luma > 8;
-
-            ff_h264dsp_init(&h->h264dsp, h->sps.bit_depth_luma,
-                            h->sps.chroma_format_idc);
-            ff_h264chroma_init(&h->h264chroma, h->sps.bit_depth_chroma);
-            ff_h264qpel_init(&h->h264qpel, h->sps.bit_depth_luma);
-            ff_h264_pred_init(&h->hpc, h->avctx->codec_id, h->sps.bit_depth_luma,
-                              h->sps.chroma_format_idc);
-            ff_videodsp_init(&h->vdsp, h->sps.bit_depth_luma);
-        } else {
-            av_log(h->avctx, AV_LOG_ERROR, "Unsupported bit depth %d\n",
-                   h->sps.bit_depth_luma);
-            return AVERROR_INVALIDDATA;
-        }
-    }
-    return 0;
-}
-
 int ff_set_ref_count(H264Context *h, H264SliceContext *sl)
 {
     int ref_count[2], list_count;
@@ -1559,10 +1520,6 @@ again:
                     ff_h264_decode_seq_parameter_set(h);
                 }
 
-                ret = ff_h264_set_parameter_from_sps(h);
-                if (ret < 0)
-                    goto end;
-
                 break;
             case NAL_PPS:
                 init_get_bits(&h->gb, ptr, bit_length);

libavcodec/h264.h

@@ -724,8 +724,6 @@ typedef struct H264Context {
     int sei_buffering_period_present;   ///< Buffering period SEI flag
     int initial_cpb_removal_delay[32];  ///< Initial timestamps for CPBs
 
-    int cur_chroma_format_idc;
-
     int enable_er;
 
     AVBufferPool *qscale_table_pool;
@@ -1073,7 +1071,6 @@ int ff_h264_ref_picture(H264Context *h, H264Picture *dst, H264Picture *src);
 void ff_h264_unref_picture(H264Context *h, H264Picture *pic);
 
 int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl);
-int ff_h264_set_parameter_from_sps(H264Context *h);
 
 void ff_h264_draw_horiz_band(const H264Context *h, H264SliceContext *sl, int y, int height);
 int ff_init_poc(H264Context *h, int pic_field_poc[2], int *pic_poc);

libavcodec/h264_slice.c

@@ -428,11 +428,6 @@ int ff_h264_update_thread_context(AVCodecContext *dst,
          h->sps.bit_depth_luma    != h1->sps.bit_depth_luma    ||
          h->sps.chroma_format_idc != h1->sps.chroma_format_idc ||
          h->sps.colorspace        != h1->sps.colorspace)) {
-
-        /* set bits_per_raw_sample to the previous value. the check for changed
-         * bit depth in h264_set_parameter_from_sps() uses it and sets it to
-         * the current value */
-        h->avctx->bits_per_raw_sample = h->sps.bit_depth_luma;
         need_reinit = 1;
     }
 
@@ -571,8 +566,6 @@ int ff_h264_update_thread_context(AVCodecContext *dst,
 
         /* copy block_offset since frame_start may not be called */
         memcpy(h->block_offset, h1->block_offset, sizeof(h->block_offset));
-
-        ff_h264_set_parameter_from_sps(h);
     }
 
     if (!h->cur_pic_ptr)
@@ -1012,6 +1005,23 @@ static int h264_slice_header_init(H264Context *h, int reinit)
         return ret;
     }
 
+    if (h->sps.bit_depth_luma < 8 || h->sps.bit_depth_luma > 10) {
+        av_log(h->avctx, AV_LOG_ERROR, "Unsupported bit depth %d\n",
+               h->sps.bit_depth_luma);
+        return AVERROR_INVALIDDATA;
+    }
+
+    h->avctx->bits_per_raw_sample = h->sps.bit_depth_luma;
+    h->pixel_shift                = h->sps.bit_depth_luma > 8;
+
+    ff_h264dsp_init(&h->h264dsp, h->sps.bit_depth_luma,
+                    h->sps.chroma_format_idc);
+    ff_h264chroma_init(&h->h264chroma, h->sps.bit_depth_chroma);
+    ff_h264qpel_init(&h->h264qpel, h->sps.bit_depth_luma);
+    ff_h264_pred_init(&h->hpc, h->avctx->codec_id, h->sps.bit_depth_luma,
+                      h->sps.chroma_format_idc);
+    ff_videodsp_init(&h->vdsp, h->sps.bit_depth_luma);
+
     if (nb_slices > H264_MAX_THREADS || (nb_slices > h->mb_height && h->mb_height)) {
         int max_slices;
         if (h->mb_height)
@@ -1152,8 +1162,20 @@ int ff_h264_decode_slice_header(H264Context *h, H264SliceContext *sl)
             h->chroma_format_idc = h->sps.chroma_format_idc;
             needs_reinit         = 1;
         }
-        if ((ret = ff_h264_set_parameter_from_sps(h)) < 0)
-            return ret;
+
+        if (h->flags & CODEC_FLAG_LOW_DELAY ||
+            (h->sps.bitstream_restriction_flag &&
+             !h->sps.num_reorder_frames)) {
+            if (h->avctx->has_b_frames > 1 || h->delayed_pic[0])
+                av_log(h->avctx, AV_LOG_WARNING, "Delayed frames seen. "
+                       "Reenabling low delay requires a codec flush.\n");
+            else
+                h->low_delay = 1;
+        }
+
+        if (h->avctx->has_b_frames < 2)
+            h->avctx->has_b_frames = !h->low_delay;
+
     }
 
     h->avctx->profile = ff_h264_get_profile(&h->sps);