h264: move cabac[_state] into the per-slice context

libavcodec/h264.h

@@ -396,6 +396,12 @@ typedef struct H264SliceContext {
     ///< as mb is addressed by scantable[i] and scantable is uint8_t we can either
     ///< check that i is not too large or ensure that there is some unused stuff after mb
     int16_t mb_padding[256 * 2];
+
+    /**
+     * Cabac
+     */
+    CABACContext cabac;
+    uint8_t cabac_state[1024];
 } H264SliceContext;
 
 /**
@@ -476,12 +482,6 @@ typedef struct H264Context {
     GetBitContext *intra_gb_ptr;
     GetBitContext *inter_gb_ptr;
 
-    /**
-     * Cabac
-     */
-    CABACContext cabac;
-    uint8_t cabac_state[1024];
-
     /* 0x100 -> non null luma_dc, 0x80/0x40 -> non null chroma_dc (cb/cr), 0x?0 -> chroma_cbp(0, 1, 2), 0x0? luma_cbp */
     uint16_t *cbp_table;
     int cbp;

libavcodec/h264_slice.c

@@ -2194,7 +2194,7 @@ static int decode_slice(struct AVCodecContext *avctx, void *arg)
         align_get_bits(&h->gb);
 
         /* init cabac */
-        ff_init_cabac_decoder(&h->cabac,
+        ff_init_cabac_decoder(&sl->cabac,
                               h->gb.buffer + get_bits_count(&h->gb) / 8,
                               (get_bits_left(&h->gb) + 7) / 8);
 
@@ -2219,21 +2219,21 @@ static int decode_slice(struct AVCodecContext *avctx, void *arg)
                     ff_h264_hl_decode_mb(h, sl);
                 h->mb_y--;
             }
-            eos = get_cabac_terminate(&h->cabac);
+            eos = get_cabac_terminate(&sl->cabac);
 
             if ((h->workaround_bugs & FF_BUG_TRUNCATED) &&
-                h->cabac.bytestream > h->cabac.bytestream_end + 2) {
+                sl->cabac.bytestream > sl->cabac.bytestream_end + 2) {
                 er_add_slice(h, sl, h->resync_mb_x, h->resync_mb_y, h->mb_x - 1,
                              h->mb_y, ER_MB_END);
                 if (h->mb_x >= lf_x_start)
                     loop_filter(h, sl, lf_x_start, h->mb_x + 1);
                 return 0;
             }
-            if (ret < 0 || h->cabac.bytestream > h->cabac.bytestream_end + 2) {
+            if (ret < 0 || sl->cabac.bytestream > sl->cabac.bytestream_end + 2) {
                 av_log(h->avctx, AV_LOG_ERROR,
                        "error while decoding MB %d %d, bytestream %td\n",
                        h->mb_x, h->mb_y,
-                       h->cabac.bytestream_end - h->cabac.bytestream);
+                       sl->cabac.bytestream_end - sl->cabac.bytestream);
                 er_add_slice(h, sl, h->resync_mb_x, h->resync_mb_y, h->mb_x,
                              h->mb_y, ER_MB_ERROR);
                 return AVERROR_INVALIDDATA;