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-rw-r--r--libavcodec/cabac.c253
1 files changed, 163 insertions, 90 deletions
diff --git a/libavcodec/cabac.c b/libavcodec/cabac.c
index b6f56f05ec..81a75dd52a 100644
--- a/libavcodec/cabac.c
+++ b/libavcodec/cabac.c
@@ -2,20 +2,20 @@
* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * 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.
*
- * Libav 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 Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
@@ -27,80 +27,25 @@
#include <string.h>
#include "libavutil/common.h"
+#include "libavutil/timer.h"
#include "get_bits.h"
#include "cabac.h"
#include "cabac_functions.h"
-uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63] = {
- 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,
-};
-
-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},
-{ 77, 94,111,128}, { 73, 89,105,122}, { 69, 85,100,116}, { 66, 80, 95,110},
-{ 62, 76, 90,104}, { 59, 72, 86, 99}, { 56, 69, 81, 94}, { 53, 65, 77, 89},
-{ 51, 62, 73, 85}, { 48, 59, 69, 80}, { 46, 56, 66, 76}, { 43, 53, 63, 72},
-{ 41, 50, 59, 69}, { 39, 48, 56, 65}, { 37, 45, 54, 62}, { 35, 43, 51, 59},
-{ 33, 41, 48, 56}, { 32, 39, 46, 53}, { 30, 37, 43, 50}, { 29, 35, 41, 48},
-{ 27, 33, 39, 45}, { 26, 31, 37, 43}, { 24, 30, 35, 41}, { 23, 28, 33, 39},
-{ 22, 27, 32, 37}, { 21, 26, 30, 35}, { 20, 24, 29, 33}, { 19, 23, 27, 31},
-{ 18, 22, 26, 30}, { 17, 21, 25, 28}, { 16, 20, 23, 27}, { 15, 19, 22, 25},
-{ 14, 18, 21, 24}, { 14, 17, 20, 23}, { 13, 16, 19, 22}, { 12, 15, 18, 21},
-{ 12, 14, 17, 20}, { 11, 14, 16, 19}, { 11, 13, 15, 18}, { 10, 12, 15, 17},
-{ 10, 12, 14, 16}, { 9, 11, 13, 15}, { 9, 11, 12, 14}, { 8, 10, 12, 14},
-{ 8, 9, 11, 13}, { 7, 9, 11, 12}, { 7, 9, 10, 12}, { 7, 8, 10, 11},
-{ 6, 8, 9, 11}, { 6, 7, 9, 10}, { 6, 7, 8, 9}, { 2, 2, 2, 2},
-};
-
-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,
- 25,26,27,28,29,30,31,32,
- 33,34,35,36,37,38,39,40,
- 41,42,43,44,45,46,47,48,
- 49,50,51,52,53,54,55,56,
- 57,58,59,60,61,62,62,63,
-};
-
-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,
- 19,19,21,21,22,22,23,24,
- 24,25,26,26,27,27,28,29,
- 29,30,30,30,31,32,32,33,
- 33,33,34,34,35,35,35,36,
- 36,36,37,37,37,38,38,63,
-};
-
-static const uint8_t last_coeff_flag_offset_8x8[63] = {
- 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
- 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
-};
+#include "cabac_tablegen.h"
+
+/**
+ *
+ * @param buf_size size of buf in bits
+ */
+void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size){
+ init_put_bits(&c->pb, buf, buf_size);
+
+ c->low= 0;
+ c->range= 0x1FE;
+ c->outstanding_count= 0;
+ c->pb.bit_left++; //avoids firstBitFlag
+}
/**
*
@@ -123,32 +68,160 @@ void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size){
void ff_init_cabac_states(void)
{
- int i, j;
static int initialized = 0;
if (initialized)
return;
- 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[j*2*64+2*i+0]=
- ff_h264_lps_range[j*2*64+2*i+1]= lps_range[i][j];
- }
+ cabac_tableinit();
+
+ initialized = 1;
+}
+
+#ifdef TEST
+#define SIZE 10240
+
+#include "libavutil/lfg.h"
+#include "avcodec.h"
- ff_h264_mlps_state[128 + 2 * i + 0] = 2 * mps_state[i] + 0;
- ff_h264_mlps_state[128 + 2 * i + 1] = 2 * mps_state[i] + 1;
+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);
+ }
+}
- if( i ){
- 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;
+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{
- ff_h264_mlps_state[128-2*i-1]= 1;
- ff_h264_mlps_state[128-2*i-2]= 0;
+ put_cabac_bit(c, 1);
+ c->low -= 0x200;
}
+
+ c->range+= c->range;
+ c->low += c->low;
}
- for(i=0; i< 63; i++){
- ff_h264_last_coeff_flag_offset_8x8[i] = last_coeff_flag_offset_8x8[i];
+}
+
+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_mlps_state[128 + *state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ *state= ff_h264_mlps_state[127 - *state];
}
- initialized = 1;
+ 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);
+
+ av_assert0(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();
+
+ for(i=0; i<SIZE; i++){
+ if(2*i<SIZE) r[i] = av_lfg_get(&prng) % 7;
+ else r[i] = (i>>8)&1;
+ }
+
+ 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")
+ }
+
+ 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) )
+ 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_noinline(&c, state) )
+ av_log(NULL, AV_LOG_ERROR, "CABAC failure at %d\n", i);
+STOP_TIMER("get_cabac")
+ }
+ if(!get_cabac_terminate(&c))
+ av_log(NULL, AV_LOG_ERROR, "where's the Terminator?\n");
+
+ return 0;
+}
+
+#endif /* TEST */
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