diff options
Diffstat (limited to 'libavcodec/cabac.c')
-rw-r--r-- | libavcodec/cabac.c | 253 |
1 files changed, 163 insertions, 90 deletions
diff --git a/libavcodec/cabac.c b/libavcodec/cabac.c index b6f56f0..81a75dd 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 */ |