From 179655b6c6f27cca2089844046bc5f280bb83814 Mon Sep 17 00:00:00 2001
From: David Conrad <lessen42@gmail.com>
Date: Fri, 28 May 2010 07:01:34 +0000
Subject: [PATCH] vp3: The DC-only IDCT is surprisingly not supposed to be
 bitexact to the full IDCT. Fix this.

Originally committed as revision 23358 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/x86/vp3dsp_mmx.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/libavcodec/x86/vp3dsp_mmx.c b/libavcodec/x86/vp3dsp_mmx.c
index 44a8477a89..188240dd08 100644
--- a/libavcodec/x86/vp3dsp_mmx.c
+++ b/libavcodec/x86/vp3dsp_mmx.c
@@ -398,9 +398,7 @@ void ff_vp3_idct_add_mmx(uint8_t *dest, int line_size, DCTELEM *block)
 
 void ff_vp3_idct_dc_add_mmx2(uint8_t *dest, int linesize, const DCTELEM *block)
 {
-    int dc = block[0];
-    dc = (46341*dc)>>16;
-    dc = (46341*dc + (8<<16))>>20;
+    int dc = (block[0] + 15) >> 5;
 
     __asm__ volatile(
         "movd          %3, %%mm0 \n\t"