* 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 Libav.
+ *
+ * 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 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,
+ * 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
+ * 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"
+#include "cabac_functions.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},
{ 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];
+static uint8_t 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,
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,
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,
+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,
- 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,
+ 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,
};
/**
c->low= 0;
c->range= 0x1FE;
c->outstanding_count= 0;
-#ifdef STRICT_LIMITS
- c->sym_count =0;
-#endif
-
c->pb.bit_left++; //avoids firstBitFlag
}
* @param buf_size size of buf in bits
*/
void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size){
- c->bytestream_start=
+ c->bytestream_start=
c->bytestream= buf;
c->bytestream_end= buf + 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]=
+ h264_mps_state[2 * i + 0] = 2 * mps_state[i] + 0;
+ ff_h264_mlps_state[128+2*i+1]=
+ 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;
+ 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{
- c->lps_state[2*i+0]= 1;
- c->lps_state[2*i+1]= 0;
+ 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
-int main(){
+
+#include "libavutil/lfg.h"
+#include "avcodec.h"
+#include "cabac.h"
+
+static inline void put_cabac_bit(CABACContext *c, int b){
+ put_bits(&c->pb, 1, b);
+ for(;c->outstanding_count; c->outstanding_count--){
+ put_bits(&c->pb, 1, 1-b);
+ }
+}
+
+static inline void renorm_cabac_encoder(CABACContext *c){
+ while(c->range < 0x100){
+ //FIXME optimize
+ if(c->low<0x100){
+ put_cabac_bit(c, 0);
+ }else if(c->low<0x200){
+ c->outstanding_count++;
+ c->low -= 0x100;
+ }else{
+ put_cabac_bit(c, 1);
+ c->low -= 0x200;
+ }
+
+ c->range+= c->range;
+ c->low += c->low;
+ }
+}
+
+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 = h264_mps_state[*state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ }
+
+ renorm_cabac_encoder(c);
+}
+
+/**
+ * @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;
+ }
+}
+
+/**
+ *
+ * @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;
+
+ 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
+ }
+
+ return (put_bits_count(&c->pb)+7)>>3;
+}
+
+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++){
START_TIMER
put_cabac_bypass(&c, r[i]&1);
STOP_TIMER("put_cabac_bypass")
}
-
+
for(i=0; i<SIZE; i++){
START_TIMER
put_cabac(&c, state, r[i]&1);
STOP_TIMER("put_cabac")
}
- for(i=0; i<SIZE; i++){
-START_TIMER
- put_cabac_u(&c, state, r[i], 6, 3, i&1);
-STOP_TIMER("put_cabac_u")
- }
-
- for(i=0; i<SIZE; i++){
-START_TIMER
- put_cabac_ueg(&c, state, r[i], 3, 0, 1, 2);
-STOP_TIMER("put_cabac_ueg")
- }
-
put_cabac_terminate(&c, 1);
-
+
ff_init_cabac_decoder(&c, b, SIZE);
-
+
memset(state, 0, sizeof(state));
-
+
for(i=0; i<SIZE; i++){
START_TIMER
if( (r[i]&1) != get_cabac_bypass(&c) )
- printf("CABAC bypass failure at %d\n", i);
+ av_log(NULL, AV_LOG_ERROR, "CABAC bypass failure at %d\n", i);
STOP_TIMER("get_cabac_bypass")
}
-
+
for(i=0; i<SIZE; i++){
START_TIMER
if( (r[i]&1) != get_cabac(&c, state) )
- printf("CABAC failure at %d\n", i);
+ av_log(NULL, AV_LOG_ERROR, "CABAC failure at %d\n", i);
STOP_TIMER("get_cabac")
}
-
- for(i=0; i<SIZE; i++){
-START_TIMER
- if( r[i] != get_cabac_u(&c, state, (i&1) ? 6 : 7, 3, i&1) )
- printf("CABAC unary (truncated) binarization failure at %d\n", i);
-STOP_TIMER("get_cabac_u")
- }
-
- for(i=0; i<SIZE; i++){
-START_TIMER
- if( r[i] != get_cabac_ueg(&c, state, 3, 0, 1, 2))
- printf("CABAC unary (truncated) binarization failure at %d\n", i);
-STOP_TIMER("get_cabac_ueg")
- }
-
if(!get_cabac_terminate(&c))
- printf("where's the Terminator?\n");
-
+ av_log(NULL, AV_LOG_ERROR, "where's the Terminator?\n");
+
return 0;
}
-#endif
+#endif /* TEST */
projects / ffmpeg / blobdiff