+ mbw = align(mc->picture_width, VL_MACROBLOCK_WIDTH) / VL_MACROBLOCK_WIDTH;
+ mbh = align(mc->picture_height, VL_MACROBLOCK_HEIGHT) / VL_MACROBLOCK_HEIGHT;
+ num_mb_per_frame = mbw * mbh;
+
+ if (mc->num_macroblocks < num_mb_per_frame)
+ return 0;
+