Move the functions in h264idct into a new file h264idct_internal.h.

Preparatory patch for high bit depth h264 decoding support.

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

2 files changed, 279 insertions, 248 deletions

diff --git a/libavcodec/h264idct.c b/libavcodec/h264idct.c
index 7c96f424b4..4a0fd1b1a7 100644
--- a/libavcodec/h264idct.c
+++ b/libavcodec/h264idct.c
@@ -25,251 +25,4 @@
  * @author Michael Niedermayer <michaelni@gmx.at>
  */
 
-#include "dsputil.h"
-
-static av_always_inline void idct_internal(uint8_t *dst, DCTELEM *block, int stride, int block_stride, int shift, int add){
-    int i;
-    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
-
-    block[0] += 1<<(shift-1);
-
-    for(i=0; i<4; i++){
-        const int z0=  block[i + block_stride*0]     +  block[i + block_stride*2];
-        const int z1=  block[i + block_stride*0]     -  block[i + block_stride*2];
-        const int z2= (block[i + block_stride*1]>>1) -  block[i + block_stride*3];
-        const int z3=  block[i + block_stride*1]     + (block[i + block_stride*3]>>1);
-
-        block[i + block_stride*0]= z0 + z3;
-        block[i + block_stride*1]= z1 + z2;
-        block[i + block_stride*2]= z1 - z2;
-        block[i + block_stride*3]= z0 - z3;
-    }
-
-    for(i=0; i<4; i++){
-        const int z0=  block[0 + block_stride*i]     +  block[2 + block_stride*i];
-        const int z1=  block[0 + block_stride*i]     -  block[2 + block_stride*i];
-        const int z2= (block[1 + block_stride*i]>>1) -  block[3 + block_stride*i];
-        const int z3=  block[1 + block_stride*i]     + (block[3 + block_stride*i]>>1);
-
-        dst[i + 0*stride]= cm[ add*dst[i + 0*stride] + ((z0 + z3) >> shift) ];
-        dst[i + 1*stride]= cm[ add*dst[i + 1*stride] + ((z1 + z2) >> shift) ];
-        dst[i + 2*stride]= cm[ add*dst[i + 2*stride] + ((z1 - z2) >> shift) ];
-        dst[i + 3*stride]= cm[ add*dst[i + 3*stride] + ((z0 - z3) >> shift) ];
-    }
-}
-
-void ff_h264_idct_add_c(uint8_t *dst, DCTELEM *block, int stride){
-    idct_internal(dst, block, stride, 4, 6, 1);
-}
-
-void ff_h264_lowres_idct_add_c(uint8_t *dst, int stride, DCTELEM *block){
-    idct_internal(dst, block, stride, 8, 3, 1);
-}
-
-void ff_h264_lowres_idct_put_c(uint8_t *dst, int stride, DCTELEM *block){
-    idct_internal(dst, block, stride, 8, 3, 0);
-}
-
-void ff_h264_idct8_add_c(uint8_t *dst, DCTELEM *block, int stride){
-    int i;
-    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
-
-    block[0] += 32;
-
-    for( i = 0; i < 8; i++ )
-    {
-        const int a0 =  block[i+0*8] + block[i+4*8];
-        const int a2 =  block[i+0*8] - block[i+4*8];
-        const int a4 = (block[i+2*8]>>1) - block[i+6*8];
-        const int a6 = (block[i+6*8]>>1) + block[i+2*8];
-
-        const int b0 = a0 + a6;
-        const int b2 = a2 + a4;
-        const int b4 = a2 - a4;
-        const int b6 = a0 - a6;
-
-        const int a1 = -block[i+3*8] + block[i+5*8] - block[i+7*8] - (block[i+7*8]>>1);
-        const int a3 =  block[i+1*8] + block[i+7*8] - block[i+3*8] - (block[i+3*8]>>1);
-        const int a5 = -block[i+1*8] + block[i+7*8] + block[i+5*8] + (block[i+5*8]>>1);
-        const int a7 =  block[i+3*8] + block[i+5*8] + block[i+1*8] + (block[i+1*8]>>1);
-
-        const int b1 = (a7>>2) + a1;
-        const int b3 =  a3 + (a5>>2);
-        const int b5 = (a3>>2) - a5;
-        const int b7 =  a7 - (a1>>2);
-
-        block[i+0*8] = b0 + b7;
-        block[i+7*8] = b0 - b7;
-        block[i+1*8] = b2 + b5;
-        block[i+6*8] = b2 - b5;
-        block[i+2*8] = b4 + b3;
-        block[i+5*8] = b4 - b3;
-        block[i+3*8] = b6 + b1;
-        block[i+4*8] = b6 - b1;
-    }
-    for( i = 0; i < 8; i++ )
-    {
-        const int a0 =  block[0+i*8] + block[4+i*8];
-        const int a2 =  block[0+i*8] - block[4+i*8];
-        const int a4 = (block[2+i*8]>>1) - block[6+i*8];
-        const int a6 = (block[6+i*8]>>1) + block[2+i*8];
-
-        const int b0 = a0 + a6;
-        const int b2 = a2 + a4;
-        const int b4 = a2 - a4;
-        const int b6 = a0 - a6;
-
-        const int a1 = -block[3+i*8] + block[5+i*8] - block[7+i*8] - (block[7+i*8]>>1);
-        const int a3 =  block[1+i*8] + block[7+i*8] - block[3+i*8] - (block[3+i*8]>>1);
-        const int a5 = -block[1+i*8] + block[7+i*8] + block[5+i*8] + (block[5+i*8]>>1);
-        const int a7 =  block[3+i*8] + block[5+i*8] + block[1+i*8] + (block[1+i*8]>>1);
-
-        const int b1 = (a7>>2) + a1;
-        const int b3 =  a3 + (a5>>2);
-        const int b5 = (a3>>2) - a5;
-        const int b7 =  a7 - (a1>>2);
-
-        dst[i + 0*stride] = cm[ dst[i + 0*stride] + ((b0 + b7) >> 6) ];
-        dst[i + 1*stride] = cm[ dst[i + 1*stride] + ((b2 + b5) >> 6) ];
-        dst[i + 2*stride] = cm[ dst[i + 2*stride] + ((b4 + b3) >> 6) ];
-        dst[i + 3*stride] = cm[ dst[i + 3*stride] + ((b6 + b1) >> 6) ];
-        dst[i + 4*stride] = cm[ dst[i + 4*stride] + ((b6 - b1) >> 6) ];
-        dst[i + 5*stride] = cm[ dst[i + 5*stride] + ((b4 - b3) >> 6) ];
-        dst[i + 6*stride] = cm[ dst[i + 6*stride] + ((b2 - b5) >> 6) ];
-        dst[i + 7*stride] = cm[ dst[i + 7*stride] + ((b0 - b7) >> 6) ];
-    }
-}
-
-// assumes all AC coefs are 0
-void ff_h264_idct_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){
-    int i, j;
-    int dc = (block[0] + 32) >> 6;
-    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP + dc;
-    for( j = 0; j < 4; j++ )
-    {
-        for( i = 0; i < 4; i++ )
-            dst[i] = cm[ dst[i] ];
-        dst += stride;
-    }
-}
-
-void ff_h264_idct8_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){
-    int i, j;
-    int dc = (block[0] + 32) >> 6;
-    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP + dc;
-    for( j = 0; j < 8; j++ )
-    {
-        for( i = 0; i < 8; i++ )
-            dst[i] = cm[ dst[i] ];
-        dst += stride;
-    }
-}
-
-//FIXME this table is a duplicate from h264data.h, and will be removed once the tables from, h264 have been split
-static const uint8_t scan8[16 + 2*4]={
- 4+1*8, 5+1*8, 4+2*8, 5+2*8,
- 6+1*8, 7+1*8, 6+2*8, 7+2*8,
- 4+3*8, 5+3*8, 4+4*8, 5+4*8,
- 6+3*8, 7+3*8, 6+4*8, 7+4*8,
- 1+1*8, 2+1*8,
- 1+2*8, 2+2*8,
- 1+4*8, 2+4*8,
- 1+5*8, 2+5*8,
-};
-
-void ff_h264_idct_add16_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
-    int i;
-    for(i=0; i<16; i++){
-        int nnz = nnzc[ scan8[i] ];
-        if(nnz){
-            if(nnz==1 && block[i*16]) ff_h264_idct_dc_add_c(dst + block_offset[i], block + i*16, stride);
-            else                      idct_internal        (dst + block_offset[i], block + i*16, stride, 4, 6, 1);
-        }
-    }
-}
-
-void ff_h264_idct_add16intra_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
-    int i;
-    for(i=0; i<16; i++){
-        if(nnzc[ scan8[i] ]) idct_internal        (dst + block_offset[i], block + i*16, stride, 4, 6, 1);
-        else if(block[i*16]) ff_h264_idct_dc_add_c(dst + block_offset[i], block + i*16, stride);
-    }
-}
-
-void ff_h264_idct8_add4_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
-    int i;
-    for(i=0; i<16; i+=4){
-        int nnz = nnzc[ scan8[i] ];
-        if(nnz){
-            if(nnz==1 && block[i*16]) ff_h264_idct8_dc_add_c(dst + block_offset[i], block + i*16, stride);
-            else                      ff_h264_idct8_add_c   (dst + block_offset[i], block + i*16, stride);
-        }
-    }
-}
-
-void ff_h264_idct_add8_c(uint8_t **dest, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
-    int i;
-    for(i=16; i<16+8; i++){
-        if(nnzc[ scan8[i] ])
-            ff_h264_idct_add_c   (dest[(i&4)>>2] + block_offset[i], block + i*16, stride);
-        else if(block[i*16])
-            ff_h264_idct_dc_add_c(dest[(i&4)>>2] + block_offset[i], block + i*16, stride);
-    }
-}
-/**
- * IDCT transforms the 16 dc values and dequantizes them.
- * @param qp quantization parameter
- */
-void ff_h264_luma_dc_dequant_idct_c(DCTELEM *output, DCTELEM *input, int qmul){
-#define stride 16
-    int i;
-    int temp[16];
-    static const uint8_t x_offset[4]={0, 2*stride, 8*stride, 10*stride};
-
-    for(i=0; i<4; i++){
-        const int z0= input[4*i+0] + input[4*i+1];
-        const int z1= input[4*i+0] - input[4*i+1];
-        const int z2= input[4*i+2] - input[4*i+3];
-        const int z3= input[4*i+2] + input[4*i+3];
-
-        temp[4*i+0]= z0+z3;
-        temp[4*i+1]= z0-z3;
-        temp[4*i+2]= z1-z2;
-        temp[4*i+3]= z1+z2;
-    }
-
-    for(i=0; i<4; i++){
-        const int offset= x_offset[i];
-        const int z0= temp[4*0+i] + temp[4*2+i];
-        const int z1= temp[4*0+i] - temp[4*2+i];
-        const int z2= temp[4*1+i] - temp[4*3+i];
-        const int z3= temp[4*1+i] + temp[4*3+i];
-
-        output[stride* 0+offset]= ((((z0 + z3)*qmul + 128 ) >> 8));
-        output[stride* 1+offset]= ((((z1 + z2)*qmul + 128 ) >> 8));
-        output[stride* 4+offset]= ((((z1 - z2)*qmul + 128 ) >> 8));
-        output[stride* 5+offset]= ((((z0 - z3)*qmul + 128 ) >> 8));
-    }
-#undef stride
-}
-
-void ff_h264_chroma_dc_dequant_idct_c(DCTELEM *block, int qmul){
-    const int stride= 16*2;
-    const int xStride= 16;
-    int a,b,c,d,e;
-
-    a= block[stride*0 + xStride*0];
-    b= block[stride*0 + xStride*1];
-    c= block[stride*1 + xStride*0];
-    d= block[stride*1 + xStride*1];
-
-    e= a-b;
-    a= a+b;
-    b= c-d;
-    c= c+d;
-
-    block[stride*0 + xStride*0]= ((a+c)*qmul) >> 7;
-    block[stride*0 + xStride*1]= ((e+b)*qmul) >> 7;
-    block[stride*1 + xStride*0]= ((a-c)*qmul) >> 7;
-    block[stride*1 + xStride*1]= ((e-b)*qmul) >> 7;
-}
+#include "h264idct_internal.h"
diff --git a/libavcodec/h264idct_internal.h b/libavcodec/h264idct_internal.h
new file mode 100644
index 0000000000..3250c7dc80
--- /dev/null
+++ b/libavcodec/h264idct_internal.h
@@ -0,0 +1,278 @@
+/*
+ * H.264 IDCT
+ * Copyright (c) 2004-2011 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * H.264 IDCT.
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+#include "dsputil.h"
+
+#ifndef AVCODEC_H264IDCT_INTERNAL_H
+#define AVCODEC_H264IDCT_INTERNAL_H
+//FIXME this table is a duplicate from h264data.h, and will be removed once the tables from, h264 have been split
+static const uint8_t scan8[16 + 2*4]={
+ 4+1*8, 5+1*8, 4+2*8, 5+2*8,
+ 6+1*8, 7+1*8, 6+2*8, 7+2*8,
+ 4+3*8, 5+3*8, 4+4*8, 5+4*8,
+ 6+3*8, 7+3*8, 6+4*8, 7+4*8,
+ 1+1*8, 2+1*8,
+ 1+2*8, 2+2*8,
+ 1+4*8, 2+4*8,
+ 1+5*8, 2+5*8,
+};
+#endif
+
+static av_always_inline void idct_internal(uint8_t *dst, DCTELEM *block, int stride, int block_stride, int shift, int add){
+    int i;
+    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+    block[0] += 1<<(shift-1);
+
+    for(i=0; i<4; i++){
+        const int z0=  block[i + block_stride*0]     +  block[i + block_stride*2];
+        const int z1=  block[i + block_stride*0]     -  block[i + block_stride*2];
+        const int z2= (block[i + block_stride*1]>>1) -  block[i + block_stride*3];
+        const int z3=  block[i + block_stride*1]     + (block[i + block_stride*3]>>1);
+
+        block[i + block_stride*0]= z0 + z3;
+        block[i + block_stride*1]= z1 + z2;
+        block[i + block_stride*2]= z1 - z2;
+        block[i + block_stride*3]= z0 - z3;
+    }
+
+    for(i=0; i<4; i++){
+        const int z0=  block[0 + block_stride*i]     +  block[2 + block_stride*i];
+        const int z1=  block[0 + block_stride*i]     -  block[2 + block_stride*i];
+        const int z2= (block[1 + block_stride*i]>>1) -  block[3 + block_stride*i];
+        const int z3=  block[1 + block_stride*i]     + (block[3 + block_stride*i]>>1);
+
+        dst[i + 0*stride]= cm[ add*dst[i + 0*stride] + ((z0 + z3) >> shift) ];
+        dst[i + 1*stride]= cm[ add*dst[i + 1*stride] + ((z1 + z2) >> shift) ];
+        dst[i + 2*stride]= cm[ add*dst[i + 2*stride] + ((z1 - z2) >> shift) ];
+        dst[i + 3*stride]= cm[ add*dst[i + 3*stride] + ((z0 - z3) >> shift) ];
+    }
+}
+
+void ff_h264_idct_add_c(uint8_t *dst, DCTELEM *block, int stride){
+    idct_internal(dst, block, stride, 4, 6, 1);
+}
+
+void ff_h264_lowres_idct_add_c(uint8_t *dst, int stride, DCTELEM *block){
+    idct_internal(dst, block, stride, 8, 3, 1);
+}
+
+void ff_h264_lowres_idct_put_c(uint8_t *dst, int stride, DCTELEM *block){
+    idct_internal(dst, block, stride, 8, 3, 0);
+}
+
+void ff_h264_idct8_add_c(uint8_t *dst, DCTELEM *block, int stride){
+    int i;
+    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+    block[0] += 32;
+
+    for( i = 0; i < 8; i++ )
+    {
+        const int a0 =  block[i+0*8] + block[i+4*8];
+        const int a2 =  block[i+0*8] - block[i+4*8];
+        const int a4 = (block[i+2*8]>>1) - block[i+6*8];
+        const int a6 = (block[i+6*8]>>1) + block[i+2*8];
+
+        const int b0 = a0 + a6;
+        const int b2 = a2 + a4;
+        const int b4 = a2 - a4;
+        const int b6 = a0 - a6;
+
+        const int a1 = -block[i+3*8] + block[i+5*8] - block[i+7*8] - (block[i+7*8]>>1);
+        const int a3 =  block[i+1*8] + block[i+7*8] - block[i+3*8] - (block[i+3*8]>>1);
+        const int a5 = -block[i+1*8] + block[i+7*8] + block[i+5*8] + (block[i+5*8]>>1);
+        const int a7 =  block[i+3*8] + block[i+5*8] + block[i+1*8] + (block[i+1*8]>>1);
+
+        const int b1 = (a7>>2) + a1;
+        const int b3 =  a3 + (a5>>2);
+        const int b5 = (a3>>2) - a5;
+        const int b7 =  a7 - (a1>>2);
+
+        block[i+0*8] = b0 + b7;
+        block[i+7*8] = b0 - b7;
+        block[i+1*8] = b2 + b5;
+        block[i+6*8] = b2 - b5;
+        block[i+2*8] = b4 + b3;
+        block[i+5*8] = b4 - b3;
+        block[i+3*8] = b6 + b1;
+        block[i+4*8] = b6 - b1;
+    }
+    for( i = 0; i < 8; i++ )
+    {
+        const int a0 =  block[0+i*8] + block[4+i*8];
+        const int a2 =  block[0+i*8] - block[4+i*8];
+        const int a4 = (block[2+i*8]>>1) - block[6+i*8];
+        const int a6 = (block[6+i*8]>>1) + block[2+i*8];
+
+        const int b0 = a0 + a6;
+        const int b2 = a2 + a4;
+        const int b4 = a2 - a4;
+        const int b6 = a0 - a6;
+
+        const int a1 = -block[3+i*8] + block[5+i*8] - block[7+i*8] - (block[7+i*8]>>1);
+        const int a3 =  block[1+i*8] + block[7+i*8] - block[3+i*8] - (block[3+i*8]>>1);
+        const int a5 = -block[1+i*8] + block[7+i*8] + block[5+i*8] + (block[5+i*8]>>1);
+        const int a7 =  block[3+i*8] + block[5+i*8] + block[1+i*8] + (block[1+i*8]>>1);
+
+        const int b1 = (a7>>2) + a1;
+        const int b3 =  a3 + (a5>>2);
+        const int b5 = (a3>>2) - a5;
+        const int b7 =  a7 - (a1>>2);
+
+        dst[i + 0*stride] = cm[ dst[i + 0*stride] + ((b0 + b7) >> 6) ];
+        dst[i + 1*stride] = cm[ dst[i + 1*stride] + ((b2 + b5) >> 6) ];
+        dst[i + 2*stride] = cm[ dst[i + 2*stride] + ((b4 + b3) >> 6) ];
+        dst[i + 3*stride] = cm[ dst[i + 3*stride] + ((b6 + b1) >> 6) ];
+        dst[i + 4*stride] = cm[ dst[i + 4*stride] + ((b6 - b1) >> 6) ];
+        dst[i + 5*stride] = cm[ dst[i + 5*stride] + ((b4 - b3) >> 6) ];
+        dst[i + 6*stride] = cm[ dst[i + 6*stride] + ((b2 - b5) >> 6) ];
+        dst[i + 7*stride] = cm[ dst[i + 7*stride] + ((b0 - b7) >> 6) ];
+    }
+}
+
+// assumes all AC coefs are 0
+void ff_h264_idct_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){
+    int i, j;
+    int dc = (block[0] + 32) >> 6;
+    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP + dc;
+    for( j = 0; j < 4; j++ )
+    {
+        for( i = 0; i < 4; i++ )
+            dst[i] = cm[ dst[i] ];
+        dst += stride;
+    }
+}
+
+void ff_h264_idct8_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){
+    int i, j;
+    int dc = (block[0] + 32) >> 6;
+    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP + dc;
+    for( j = 0; j < 8; j++ )
+    {
+        for( i = 0; i < 8; i++ )
+            dst[i] = cm[ dst[i] ];
+        dst += stride;
+    }
+}
+
+void ff_h264_idct_add16_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
+    int i;
+    for(i=0; i<16; i++){
+        int nnz = nnzc[ scan8[i] ];
+        if(nnz){
+            if(nnz==1 && block[i*16]) ff_h264_idct_dc_add_c(dst + block_offset[i], block + i*16, stride);
+            else                      idct_internal        (dst + block_offset[i], block + i*16, stride, 4, 6, 1);
+        }
+    }
+}
+
+void ff_h264_idct_add16intra_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
+    int i;
+    for(i=0; i<16; i++){
+        if(nnzc[ scan8[i] ]) idct_internal        (dst + block_offset[i], block + i*16, stride, 4, 6, 1);
+        else if(block[i*16]) ff_h264_idct_dc_add_c(dst + block_offset[i], block + i*16, stride);
+    }
+}
+
+void ff_h264_idct8_add4_c(uint8_t *dst, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
+    int i;
+    for(i=0; i<16; i+=4){
+        int nnz = nnzc[ scan8[i] ];
+        if(nnz){
+            if(nnz==1 && block[i*16]) ff_h264_idct8_dc_add_c(dst + block_offset[i], block + i*16, stride);
+            else                      ff_h264_idct8_add_c   (dst + block_offset[i], block + i*16, stride);
+        }
+    }
+}
+
+void ff_h264_idct_add8_c(uint8_t **dest, const int *block_offset, DCTELEM *block, int stride, const uint8_t nnzc[6*8]){
+    int i;
+    for(i=16; i<16+8; i++){
+        if(nnzc[ scan8[i] ])
+            ff_h264_idct_add_c   (dest[(i&4)>>2] + block_offset[i], block + i*16, stride);
+        else if(block[i*16])
+            ff_h264_idct_dc_add_c(dest[(i&4)>>2] + block_offset[i], block + i*16, stride);
+    }
+}
+/**
+ * IDCT transforms the 16 dc values and dequantizes them.
+ * @param qp quantization parameter
+ */
+void ff_h264_luma_dc_dequant_idct_c(DCTELEM *output, DCTELEM *input, int qmul){
+#define stride 16
+    int i;
+    int temp[16];
+    static const uint8_t x_offset[4]={0, 2*stride, 8*stride, 10*stride};
+
+    for(i=0; i<4; i++){
+        const int z0= input[4*i+0] + input[4*i+1];
+        const int z1= input[4*i+0] - input[4*i+1];
+        const int z2= input[4*i+2] - input[4*i+3];
+        const int z3= input[4*i+2] + input[4*i+3];
+
+        temp[4*i+0]= z0+z3;
+        temp[4*i+1]= z0-z3;
+        temp[4*i+2]= z1-z2;
+        temp[4*i+3]= z1+z2;
+    }
+
+    for(i=0; i<4; i++){
+        const int offset= x_offset[i];
+        const int z0= temp[4*0+i] + temp[4*2+i];
+        const int z1= temp[4*0+i] - temp[4*2+i];
+        const int z2= temp[4*1+i] - temp[4*3+i];
+        const int z3= temp[4*1+i] + temp[4*3+i];
+
+        output[stride* 0+offset]= ((((z0 + z3)*qmul + 128 ) >> 8));
+        output[stride* 1+offset]= ((((z1 + z2)*qmul + 128 ) >> 8));
+        output[stride* 4+offset]= ((((z1 - z2)*qmul + 128 ) >> 8));
+        output[stride* 5+offset]= ((((z0 - z3)*qmul + 128 ) >> 8));
+    }
+#undef stride
+}
+
+void ff_h264_chroma_dc_dequant_idct_c(DCTELEM *block, int qmul){
+    const int stride= 16*2;
+    const int xStride= 16;
+    int a,b,c,d,e;
+
+    a= block[stride*0 + xStride*0];
+    b= block[stride*0 + xStride*1];
+    c= block[stride*1 + xStride*0];
+    d= block[stride*1 + xStride*1];
+
+    e= a-b;
+    a= a+b;
+    b= c-d;
+    c= c+d;
+
+    block[stride*0 + xStride*0]= ((a+c)*qmul) >> 7;
+    block[stride*0 + xStride*1]= ((e+b)*qmul) >> 7;
+    block[stride*1 + xStride*0]= ((a-c)*qmul) >> 7;
+    block[stride*1 + xStride*1]= ((e-b)*qmul) >> 7;
+}