* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
*/
/**
- * @file cabac.c
+ * @file
* 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"
static const uint8_t lps_range[64][4]= {
{ 6, 8, 9, 11}, { 6, 7, 9, 10}, { 6, 7, 8, 9}, { 2, 2, 2, 2},
};
-uint8_t ff_h264_lps_range[2*65][4];
+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];
36,36,37,37,37,38,38,63,
};
-const uint8_t ff_h264_norm_shift[128]= {
- 7,6,5,5,4,4,4,4,3,3,3,3,3,3,3,3,
+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,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
- 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 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,
};
/**
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){
for(i=0; i<64; i++){
for(j=0; j<4; j++){ //FIXME check if this is worth the 1 shift we save
- ff_h264_lps_range[2*i+0][j+4]=
- ff_h264_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];
}
+ 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 ){
-#ifdef BRANCHLESS_CABAC_DECODER
- ff_h264_mps_state[-2*i-1]= 2*lps_state[i]+0; //FIXME yes this is not valid C but iam lazy, cleanup welcome
- ff_h264_mps_state[-2*i-2]= 2*lps_state[i]+1;
- }else{
- ff_h264_mps_state[-2*i-1]= 1;
- ff_h264_mps_state[-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;
+ 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_lps_state[2*i+0]= 1;
- ff_h264_lps_state[2*i+1]= 0;
-#endif
+ ff_h264_mlps_state[128-2*i-1]= 1;
+ ff_h264_mlps_state[128-2*i-2]= 0;
}
}
}
-#if 0 //selftest
+#ifdef TEST
#define SIZE 10240
+#include "libavutil/lfg.h"
#include "avcodec.h"
+#include "cabac.h"
+
+static void put_cabac(CABACContext *c, uint8_t * const state, int bit){
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + *state];
+
+ if(bit == ((*state)&1)){
+ c->range -= RangeLPS;
+ *state= ff_h264_mps_state[*state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ *state= ff_h264_lps_state[*state];
+ }
+
+ renorm_cabac_encoder(c);
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ * @param bit 0 -> write zero bit, !=0 write one bit
+ */
+static void put_cabac_bypass(CABACContext *c, int bit){
+ c->low += c->low;
+
+ if(bit){
+ c->low += c->range;
+ }
+//FIXME optimize
+ if(c->low<0x200){
+ put_cabac_bit(c, 0);
+ }else if(c->low<0x400){
+ c->outstanding_count++;
+ c->low -= 0x200;
+ }else{
+ put_cabac_bit(c, 1);
+ c->low -= 0x400;
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ *
+ * @return the number of bytes written
+ */
+static int put_cabac_terminate(CABACContext *c, int bit){
+ c->range -= 2;
+
+ if(!bit){
+ renorm_cabac_encoder(c);
+ }else{
+ c->low += c->range;
+ c->range= 2;
-int main(){
+ renorm_cabac_encoder(c);
+
+ assert(c->low <= 0x1FF);
+ put_cabac_bit(c, c->low>>9);
+ put_bits(&c->pb, 2, ((c->low>>7)&3)|1);
+
+ flush_put_bits(&c->pb); //FIXME FIXME FIXME XXX wrong
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+
+ return (put_bits_count(&c->pb)+7)>>3;
+}
+
+/**
+ * put (truncated) unary binarization.
+ */
+static void put_cabac_u(CABACContext *c, uint8_t * state, int v, int max, int max_index, int truncated){
+ int i;
+
+ assert(v <= max);
+
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+ if(truncated==0 || v<max)
+ put_cabac(c, state, 0);
+}
+
+/**
+ * put unary exp golomb k-th order binarization.
+ */
+static void put_cabac_ueg(CABACContext *c, uint8_t * state, int v, int max, int is_signed, int k, int max_index){
+ int i;
+
+ if(v==0)
+ put_cabac(c, state, 0);
+ else{
+ const int sign= v < 0;
+
+ if(is_signed) v= FFABS(v);
+
+ if(v<max){
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ put_cabac(c, state, 0);
+ }else{
+ int m= 1<<k;
+
+ for(i=0; i<max; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ v -= max;
+ while(v >= m){ //FIXME optimize
+ put_cabac_bypass(c, 1);
+ v-= m;
+ m+= m;
+ }
+ put_cabac_bypass(c, 0);
+ while(m>>=1){
+ put_cabac_bypass(c, v&m);
+ }
+ }
+
+ if(is_signed)
+ put_cabac_bypass(c, sign);
+ }
+}
+
+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++){
return 0;
}
-#endif
+#endif /* TEST */
projects / ffmpeg / blobdiff