]> rtime.felk.cvut.cz Git - frescor/ffmpeg.git/blobdiff - libavcodec/cabac.c
Started implementation of "correct" O_DIRECT handling
[frescor/ffmpeg.git] / libavcodec / cabac.c
index 0c5dc1d348f6ac93bd02ff3261521a53dc0dfcf7..9a3bdafb8fd133de80c9b4a7e2cf451778b82b97 100644 (file)
@@ -2,34 +2,35 @@
  * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
  *
- * This library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
  *
- * This library is distributed in the hope that it will be useful,
+ * 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**
- * @file cabac.c
+ * @file libavcodec/cabac.c
  * Context Adaptive Binary Arithmetic Coder.
  */
 
 #include <string.h>
 
-#include "common.h"
-#include "bitstream.h"
+#include "libavutil/common.h"
+#include "get_bits.h"
 #include "cabac.h"
 
-const uint8_t ff_h264_lps_range[64][4]= {
+static const uint8_t lps_range[64][4]= {
 {128,176,208,240}, {128,167,197,227}, {128,158,187,216}, {123,150,178,205},
 {116,142,169,195}, {111,135,160,185}, {105,128,152,175}, {100,122,144,166},
 { 95,116,137,158}, { 90,110,130,150}, { 85,104,123,142}, { 81, 99,117,135},
@@ -48,7 +49,12 @@ const uint8_t ff_h264_lps_range[64][4]= {
 {  6,  8,  9, 11}, {  6,  7,  9, 10}, {  6,  7,  8,  9}, {  2,  2,  2,  2},
 };
 
-const uint8_t ff_h264_mps_state[64]= {
+uint8_t ff_h264_mlps_state[4*64];
+uint8_t ff_h264_lps_range[4*2*64];
+uint8_t ff_h264_lps_state[2*64];
+uint8_t ff_h264_mps_state[2*64];
+
+static const uint8_t mps_state[64]= {
   1, 2, 3, 4, 5, 6, 7, 8,
   9,10,11,12,13,14,15,16,
  17,18,19,20,21,22,23,24,
@@ -59,7 +65,7 @@ const uint8_t ff_h264_mps_state[64]= {
  57,58,59,60,61,62,62,63,
 };
 
-const uint8_t ff_h264_lps_state[64]= {
+static const uint8_t lps_state[64]= {
   0, 0, 1, 2, 2, 4, 4, 5,
   6, 7, 8, 9, 9,11,11,12,
  13,13,15,15,16,16,18,18,
@@ -69,25 +75,40 @@ const uint8_t ff_h264_lps_state[64]= {
  33,33,34,34,35,35,35,36,
  36,36,37,37,37,38,38,63,
 };
-
-const uint8_t ff_h264_norm_shift[256]= {
- 8,7,6,6,5,5,5,5,4,4,4,4,4,4,4,4,
- 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
- 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+#if 0
+const uint8_t ff_h264_norm_shift_old[128]= {
+ 7,6,5,5,4,4,4,4,3,3,3,3,3,3,3,3,
  2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
- 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
- 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 };
+#endif
+const uint8_t ff_h264_norm_shift[512]= {
+ 9,8,7,7,6,6,6,6,5,5,5,5,5,5,5,5,
+ 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+ 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
+ 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
+ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+};
 
 /**
  *
@@ -122,49 +143,62 @@ void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size){
     c->low =  (*c->bytestream++)<<10;
 #endif
     c->low+= ((*c->bytestream++)<<2) + 2;
-    c->range= 0x1FE<<(CABAC_BITS + 1);
+    c->range= 0x1FE;
 }
 
-void ff_init_cabac_states(CABACContext *c, uint8_t const (*lps_range)[4],
-                          uint8_t const *mps_state, uint8_t const *lps_state, int state_count){
+void ff_init_cabac_states(CABACContext *c){
     int i, j;
 
-    for(i=0; i<state_count; i++){
+    for(i=0; i<64; i++){
         for(j=0; j<4; j++){ //FIXME check if this is worth the 1 shift we save
-            c->lps_range[2*i+0][j+4]=
-            c->lps_range[2*i+1][j+4]= lps_range[i][j];
+            ff_h264_lps_range[j*2*64+2*i+0]=
+            ff_h264_lps_range[j*2*64+2*i+1]= lps_range[i][j];
         }
 
-        c->mps_state[2*i+0]= 2*mps_state[i];
-        c->mps_state[2*i+1]= 2*mps_state[i]+1;
+        ff_h264_mlps_state[128+2*i+0]=
+        ff_h264_mps_state[2*i+0]= 2*mps_state[i]+0;
+        ff_h264_mlps_state[128+2*i+1]=
+        ff_h264_mps_state[2*i+1]= 2*mps_state[i]+1;
 
         if( i ){
-            c->lps_state[2*i+0]= 2*lps_state[i];
-            c->lps_state[2*i+1]= 2*lps_state[i]+1;
+#ifdef BRANCHLESS_CABAC_DECODER
+            ff_h264_mlps_state[128-2*i-1]= 2*lps_state[i]+0;
+            ff_h264_mlps_state[128-2*i-2]= 2*lps_state[i]+1;
+        }else{
+            ff_h264_mlps_state[128-2*i-1]= 1;
+            ff_h264_mlps_state[128-2*i-2]= 0;
+#else
+            ff_h264_lps_state[2*i+0]= 2*lps_state[i]+0;
+            ff_h264_lps_state[2*i+1]= 2*lps_state[i]+1;
         }else{
-            c->lps_state[2*i+0]= 1;
-            c->lps_state[2*i+1]= 0;
+            ff_h264_lps_state[2*i+0]= 1;
+            ff_h264_lps_state[2*i+1]= 0;
+#endif
         }
     }
 }
 
-#if 0 //selftest
+#ifdef TEST
 #define SIZE 10240
 
+#include "libavutil/lfg.h"
 #include "avcodec.h"
+#include "cabac.h"
 
-int main(){
+int main(void){
     CABACContext c;
     uint8_t b[9*SIZE];
     uint8_t r[9*SIZE];
     int i;
     uint8_t state[10]= {0};
+    AVLFG prng;
 
+    av_lfg_init(&prng, 1);
     ff_init_cabac_encoder(&c, b, SIZE);
-    ff_init_cabac_states(&c, ff_h264_lps_range, ff_h264_mps_state, ff_h264_lps_state, 64);
+    ff_init_cabac_states(&c);
 
     for(i=0; i<SIZE; i++){
-        r[i]= random()%7;
+        r[i] = av_lfg_get(&prng) % 7;
     }
 
     for(i=0; i<SIZE; i++){
@@ -231,4 +265,4 @@ STOP_TIMER("get_cabac_ueg")
     return 0;
 }
 
-#endif
+#endif /* TEST */