h264: eliminate max_contexts

It is always equal to nb_slice_ctx.

libavcodec/h264.c

@@ -808,7 +808,6 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
     int nals_needed = 0; ///< number of NALs that need decoding before the next frame thread starts
     int i, ret = 0;
 
-    h->max_contexts = h->nb_slice_ctx;
     if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS)) {
         h->current_slice = 0;
         if (!h->first_field)
@@ -935,7 +934,7 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
                    nal->type, nal->size_bits);
         }
 
-        if (context_count == h->max_contexts) {
+        if (context_count == h->nb_slice_ctx) {
             ret = ff_h264_execute_decode_slices(h, context_count);
             if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
                 goto end;

libavcodec/h264.h

@@ -584,14 +584,6 @@ typedef struct H264Context {
      */
     int current_slice;
 
-    /**
-     * Max number of threads / contexts.
-     * This is equal to AVCodecContext.thread_count unless
-     * multithreaded decoding is impossible, in which case it is
-     * reduced to 1.
-     */
-    int max_contexts;
-
     /** @} */
 
     /**

libavcodec/h264_slice.c

@@ -1462,7 +1462,7 @@ int ff_h264_decode_slice_header(H264Context *h, H264SliceContext *sl)
          h->nal_ref_idc == 0))
         sl->deblocking_filter = 0;
 
-    if (sl->deblocking_filter == 1 && h->max_contexts > 1) {
+    if (sl->deblocking_filter == 1 && h->nb_slice_ctx > 1) {
         if (h->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
             /* Cheat slightly for speed:
              * Do not bother to deblock across slices. */