@@ -474,7 +474,7 @@ static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *data_size,

     int keyframe, has_wmv9, has_mv, is_rle, is_555, ret;

     Rectangle wmv9rects[MAX_WMV9_RECTANGLES], *r;

-    int used_rects = 0, i, implicit_rect, av_uninit(wmv9_mask);

+    int used_rects = 0, i, implicit_rect = 0, av_uninit(wmv9_mask);

     av_assert0(FF_INPUT_BUFFER_PADDING_SIZE >=

                ARITH2_PADDING + (MIN_CACHE_BITS + 7) / 8);

@@ -650,7 +650,14 @@ static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *data_size,

             return AVERROR_INVALIDDATA;

         buf_size -= bytestream2_tell(&gB);

-    } else if (is_rle) {

+    } else {

+        if (keyframe) {

+            c->corrupted = 0;

+            ff_mss12_slicecontext_reset(&ctx->sc[0]);

+            if (c->slice_split)

+                ff_mss12_slicecontext_reset(&ctx->sc[1]);

+        }

+    if (is_rle) {

         init_get_bits(&gb, buf, buf_size * 8);

         if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,

                              c->rgb_pic, c->rgb_stride, c->pal, keyframe,

@@ -669,14 +676,8 @@ static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *data_size,

         align_get_bits(&gb);

         buf      += get_bits_count(&gb) >> 3;

         buf_size -= get_bits_count(&gb) >> 3;

-    } else {

-        if (keyframe) {

-            c->corrupted = 0;

-            ff_mss12_slicecontext_reset(&ctx->sc[0]);

-            if (c->slice_split)

-                ff_mss12_slicecontext_reset(&ctx->sc[1]);

-        }

-        else if (c->corrupted)

+    } else if (!implicit_rect || wmv9_mask != -1) {

+        if (c->corrupted)

             return AVERROR_INVALIDDATA;

         bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);

         arith2_init(&acoder, &gB);

@@ -702,6 +703,8 @@ static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *data_size,

             buf      += arith2_get_consumed_bytes(&acoder);

             buf_size -= arith2_get_consumed_bytes(&acoder);

         }

+    } else

+        memset(c->pal_pic, 0, c->pal_stride * avctx->height);

     }

     if (has_wmv9) {