Merge commit 'fbd0dacc8d61ab418b3fa8e7be22017558323e56'

* commit 'fbd0dacc8d61ab418b3fa8e7be22017558323e56':
  4xm: refactor decode_p_block

Conflicts:
	libavcodec/4xm.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>

diff --cc libavcodec/4xm.c
index dc0ad506d583c78cd2c83d4ce12b682c9936fb9e,5814c3afd48fff7e74bd570a0e94ae6b379f471c..5a20c13b80f39d2ffbbc72de40037569dad0403f
--- 1/libavcodec/4xm.c
--- 2/libavcodec/4xm.c
+++ b/libavcodec/4xm.c
@@@ -344,21 -342,13 +344,12 @@@ static int decode_p_block(FourXContext 
      uint16_t *start = (uint16_t *)f->last_picture->data[0];
      uint16_t *end   = start + stride * (f->avctx->height - h + 1) - (1 << log2w);
      int ret;
+     int scale   = 1;
+     unsigned dc = 0;
  
 -    if (code < 0 || code > 6 || log2w < 0)
 -        return AVERROR_INVALIDDATA;
 +    av_assert0(code >= 0 && code <= 6 && log2w >= 0);
  
-     if (code == 0) {
-         if (bytestream2_get_bytes_left(&f->g) < 1) {
-             av_log(f->avctx, AV_LOG_ERROR, "bytestream overread\n");
-             return AVERROR_INVALIDDATA;
-         }
-         src += f->mv[bytestream2_get_byteu(&f->g)];
-         if (start > src || src > end) {
-             av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n");
-             return AVERROR_INVALIDDATA;
-         }
-         mcdc(dst, src, log2w, h, stride, 1, 0);
-     } else if (code == 1) {
+     if (code == 1) {
          log2h--;
          if ((ret = decode_p_block(f, dst, src, log2w, log2h, stride)) < 0)
              return ret;
@@@ -370,48 -359,39 +360,57 @@@
          log2w--;
          if ((ret = decode_p_block(f, dst , src, log2w, log2h, stride)) < 0)
              return ret;
-         if ((ret = decode_p_block(f, dst + (1 << log2w),
-                                   src + (1 << log2w),
-                                   log2w, log2h, stride)) < 0)
-             return ret;
-     } else if (code == 3 && f->version < 2) {
-         av_assert0(start <= src && src <= end);
-         mcdc(dst, src, log2w, h, stride, 1, 0);
-     } else if (code == 4) {
-         if (bytestream2_get_bytes_left(&f->g) < 1) {
-             av_log(f->avctx, AV_LOG_ERROR, "bytestream overread\n");
-             return AVERROR_INVALIDDATA;
-         }
-         src += f->mv[bytestream2_get_byteu(&f->g)];
-         if (start > src || src > end) {
-             av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n");
-             return AVERROR_INVALIDDATA;
-         }
-         if (bytestream2_get_bytes_left(&f->g2) < 2){
-             av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n");
-             return AVERROR_INVALIDDATA;
-         }
-         mcdc(dst, src, log2w, h, stride, 1, bytestream2_get_le16u(&f->g2));
-     } else if (code == 5) {
-         if (bytestream2_get_bytes_left(&f->g2) < 2) {
-             av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n");
-             return AVERROR_INVALIDDATA;
-         }
-         av_assert0(start <= src && src <= end);
-         mcdc(dst, src, log2w, h, stride, 0, bytestream2_get_le16u(&f->g2));
+         return decode_p_block(f, dst + (1 << log2w),
+                               src + (1 << log2w),
+                               log2w, log2h, stride);
      } else if (code == 6) {
 +        if (bytestream2_get_bytes_left(&f->g2) < 4) {
 +            av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n");
 +            return AVERROR_INVALIDDATA;
 +        }
          if (log2w) {
 -            dst[0]      = bytestream2_get_le16(&f->g2);
 -            dst[1]      = bytestream2_get_le16(&f->g2);
 +            dst[0]      = bytestream2_get_le16u(&f->g2);
 +            dst[1]      = bytestream2_get_le16u(&f->g2);
          } else {
 -            dst[0]      = bytestream2_get_le16(&f->g2);
 -            dst[stride] = bytestream2_get_le16(&f->g2);
 +            dst[0]      = bytestream2_get_le16u(&f->g2);
 +            dst[stride] = bytestream2_get_le16u(&f->g2);
          }
+         return 0;
+     }
+ 
++    if ((code&3)==0 && bytestream2_get_bytes_left(&f->g) < 1) {
++        av_log(f->avctx, AV_LOG_ERROR, "bytestream overread\n");
++        return AVERROR_INVALIDDATA;
 +    }
++
+     if (code == 0) {
+         src  += f->mv[bytestream2_get_byte(&f->g)];
+     } else if (code == 3 && f->version >= 2) {
+         return 0;
+     } else if (code == 4) {
+         src  += f->mv[bytestream2_get_byte(&f->g)];
++        if (bytestream2_get_bytes_left(&f->g2) < 2){
++            av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n");
++            return AVERROR_INVALIDDATA;
++        }
+         dc    = bytestream2_get_le16(&f->g2);
+     } else if (code == 5) {
++        if (bytestream2_get_bytes_left(&f->g2) < 2){
++            av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n");
++            return AVERROR_INVALIDDATA;
++        }
++        av_assert0(start <= src && src <= end);
+         scale = 0;
+         dc    = bytestream2_get_le16(&f->g2);
+     }
+ 
+     if (start > src || src > end) {
+         av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n");
+         return AVERROR_INVALIDDATA;
+     }
+ 
+     mcdc(dst, src, log2w, h, stride, scale, dc);
+ 
      return 0;
  }