* 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
*/
#include <string.h>
#include "libavutil/common.h"
+#include "libavutil/timer.h"
#include "get_bits.h"
#include "cabac.h"
#include "cabac_functions.h"
5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
};
+/**
+ *
+ * @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
+}
+
/**
*
* @param buf_size size of buf in bits
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] = 2 * mps_state[i] + 0;
ff_h264_mlps_state[128 + 2 * i + 1] = 2 * mps_state[i] + 1;
initialized = 1;
}
+
+#ifdef TEST
+#define SIZE 10240
+
+#include "libavutil/lfg.h"
+#include "avcodec.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 = ff_h264_mlps_state[128 + *state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ *state= ff_h264_mlps_state[127 - *state];
+ }
+
+ 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 */
projects / ffmpeg / blobdiff