fraps: fix off-by one bug for version 1.

CC:libav-stable@libav.org

cmdutils.c

@@ -1566,7 +1566,7 @@ static int alloc_buffer(FrameBuffer **pool, AVCodecContext *s, FrameBuffer **pbu
     /* XXX this shouldn't be needed, but some tests break without this line
      * those decoders are buggy and need to be fixed.
      * the following tests fail:
-     * fraps-v1, qtrle-1bit
+     * qtrle-1bit
      */
     memset(buf->base[0], 128, ret);
 

libavcodec/fraps.c

@@ -239,7 +239,7 @@ static int decode_frame(AVCodecContext *avctx,
 
         if (f->pict_type == AV_PICTURE_TYPE_I) {
             for (y = 0; y<avctx->height; y++)
-                memcpy(&f->data[0][(avctx->height - y) * f->linesize[0]],
+                memcpy(&f->data[0][(avctx->height - y - 1) * f->linesize[0]],
                        &buf[y * avctx->width * 3],
                        3 * avctx->width);
         }

tests/ref/fate/fraps-v1

 #tb 0: 1/25
-0,          0,          0,        1,   230400, 0x6bc891ff
+0,          0,          0,        1,   230400, 0x23c29d17