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Diffstat (limited to 'contrib/ffmpeg/libavcodec/cabac.c')
-rw-r--r--contrib/ffmpeg/libavcodec/cabac.c265
1 files changed, 265 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/cabac.c b/contrib/ffmpeg/libavcodec/cabac.c
new file mode 100644
index 000000000..c6da6292a
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+++ b/contrib/ffmpeg/libavcodec/cabac.c
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+/*
+ * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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 2.1 of the License, or (at your option) any later version.
+ *
+ * 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+/**
+ * @file cabac.c
+ * Context Adaptive Binary Arithmetic Coder.
+ */
+
+#include <string.h>
+
+#include "common.h"
+#include "bitstream.h"
+#include "cabac.h"
+
+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},
+};
+
+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,
+ 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,
+};
+#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,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+ 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,
+};
+
+/**
+ *
+ * @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;
+#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= buf;
+ c->bytestream_end= buf + buf_size;
+
+#if CABAC_BITS == 16
+ c->low = (*c->bytestream++)<<18;
+ c->low+= (*c->bytestream++)<<10;
+#else
+ c->low = (*c->bytestream++)<<10;
+#endif
+ c->low+= ((*c->bytestream++)<<2) + 2;
+ c->range= 0x1FE;
+}
+
+void ff_init_cabac_states(CABACContext *c){
+ int i, j;
+
+ 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];
+ }
+
+ 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_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{
+ ff_h264_lps_state[2*i+0]= 1;
+ ff_h264_lps_state[2*i+1]= 0;
+#endif
+ }
+ }
+}
+
+#if 0 //selftest
+#define SIZE 10240
+
+#include "avcodec.h"
+
+int main(){
+ CABACContext c;
+ uint8_t b[9*SIZE];
+ uint8_t r[9*SIZE];
+ int i;
+ uint8_t state[10]= {0};
+
+ 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);
+
+ for(i=0; i<SIZE; i++){
+ r[i]= random()%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) )
+ 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) )
+ av_log(NULL, AV_LOG_ERROR, "CABAC failure at %d\n", i);
+STOP_TIMER("get_cabac")
+ }
+#if 0
+ for(i=0; i<SIZE; i++){
+START_TIMER
+ if( r[i] != get_cabac_u(&c, state, (i&1) ? 6 : 7, 3, i&1) )
+ av_log(NULL, AV_LOG_ERROR, "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))
+ av_log(NULL, AV_LOG_ERROR, "CABAC unary (truncated) binarization failure at %d\n", i);
+STOP_TIMER("get_cabac_ueg")
+ }
+#endif
+ if(!get_cabac_terminate(&c))
+ av_log(NULL, AV_LOG_ERROR, "where's the Terminator?\n");
+
+ return 0;
+}
+
+#endif