X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fcabac.h;h=426f338e34e653ebf3a135280641be0b0a021568;hb=6cf7f30655e95e27fd0394b5a80970d6f9517015;hp=2f8a8d9fe7d5d6841bbb11c647163e13d03d1be8;hpb=1c2a417f6a51c94de6d8b64d2aecc476f89b50f1;p=ffmpeg diff --git a/libavcodec/cabac.h b/libavcodec/cabac.h index 2f8a8d9fe7d..426f338e34e 100644 --- a/libavcodec/cabac.h +++ b/libavcodec/cabac.h @@ -2,32 +2,40 @@ * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder * Copyright (c) 2003 Michael Niedermayer * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * 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 2.1 of the License, or (at your option) any later version. * - * FFmpeg 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 FFmpeg; if not, write to the Free Software + * 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.h + * @file * Context Adaptive Binary Arithmetic Coder. */ +#ifndef AVCODEC_CABAC_H +#define AVCODEC_CABAC_H + +#include + +#include "put_bits.h" -//#undef NDEBUG -#include +extern uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63]; +#define H264_NORM_SHIFT_OFFSET 0 +#define H264_LPS_RANGE_OFFSET 512 +#define H264_MLPS_STATE_OFFSET 1024 +#define H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET 1280 #define CABAC_BITS 16 #define CABAC_MASK ((1<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= c->lps_range[*state][c->range>>6]; - - if(bit == ((*state)&1)){ - c->range -= RangeLPS; - *state= c->mps_state[*state]; - }else{ - c->low += c->range - RangeLPS; - c->range = RangeLPS; - *state= c->lps_state[*state]; - } - - renorm_cabac_encoder(c); - -#ifdef STRICT_LIMITS - c->symCount++; -#endif -} - -static void put_cabac_static(CABACContext *c, int RangeLPS, int bit){ - assert(c->range > RangeLPS); - - if(!bit){ - c->range -= RangeLPS; - }else{ - c->low += c->range - RangeLPS; - c->range = RangeLPS; - } - - renorm_cabac_encoder(c); - -#ifdef STRICT_LIMITS - c->symCount++; -#endif -} - -/** - * @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; - } - -#ifdef STRICT_LIMITS - c->symCount++; -#endif -} - -/** - * - * @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 - } - -#ifdef STRICT_LIMITS - c->symCount++; -#endif - - return (put_bits_count(&c->pb)+7)>>3; -} - -/** - * put (truncated) unary binarization. - */ -static void put_cabac_u(CABACContext *c, uint8_t * state, int v, int max, int max_index, int truncated){ - int i; - - assert(v <= max); - -#if 1 - for(i=0; i= m){ //FIXME optimize - put_cabac_bypass(c, 1); - v-= m; - m+= m; - } - put_cabac_bypass(c, 0); - while(m>>=1){ - put_cabac_bypass(c, v&m); - } - } - - if(is_signed) - put_cabac_bypass(c, sign); - } -} - -static void refill(CABACContext *c){ -#if CABAC_BITS == 16 - c->low+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); -#else - c->low+= c->bytestream[0]<<1; -#endif - c->low -= CABAC_MASK; - c->bytestream+= CABAC_BITS/8; -} - -static void refill2(CABACContext *c){ - int i, x; - - x= c->low ^ (c->low-1); - i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS+1)]; - - x= -CABAC_MASK; - -#if CABAC_BITS == 16 - x+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); -#else - x+= c->bytestream[0]<<1; -#endif - - c->low += x<bytestream+= CABAC_BITS/8; -} - -static inline void renorm_cabac_decoder(CABACContext *c){ - while(c->range < (0x200 << CABAC_BITS)){ - c->range+= c->range; - c->low+= c->low; - if(!(c->low & CABAC_MASK)) - refill(c); - } -} - -static inline void renorm_cabac_decoder_once(CABACContext *c){ -#ifdef ARCH_X86_DISABLED - int temp; -#if 0 - //P3:683 athlon:475 - asm( - "lea -0x2000000(%0), %2 \n\t" - "shr $31, %2 \n\t" //FIXME 31->63 for x86-64 - "shl %%cl, %0 \n\t" - "shl %%cl, %1 \n\t" - : "+r"(c->range), "+r"(c->low), "+c"(temp) - ); -#elif 0 - //P3:680 athlon:474 - asm( - "cmp $0x2000000, %0 \n\t" - "setb %%cl \n\t" //FIXME 31->63 for x86-64 - "shl %%cl, %0 \n\t" - "shl %%cl, %1 \n\t" - : "+r"(c->range), "+r"(c->low), "+c"(temp) - ); -#elif 1 - int temp2; - //P3:665 athlon:517 - asm( - "lea -0x2000000(%0), %%eax \n\t" - "cdq \n\t" - "mov %0, %%eax \n\t" - "and %%edx, %0 \n\t" - "and %1, %%edx \n\t" - "add %%eax, %0 \n\t" - "add %%edx, %1 \n\t" - : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2) - ); -#elif 0 - int temp2; - //P3:673 athlon:509 - asm( - "cmp $0x2000000, %0 \n\t" - "sbb %%edx, %%edx \n\t" - "mov %0, %%eax \n\t" - "and %%edx, %0 \n\t" - "and %1, %%edx \n\t" - "add %%eax, %0 \n\t" - "add %%edx, %1 \n\t" - : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2) - ); -#else - int temp2; - //P3:677 athlon:511 - asm( - "cmp $0x2000000, %0 \n\t" - "lea (%0, %0), %%eax \n\t" - "lea (%1, %1), %%edx \n\t" - "cmovb %%eax, %0 \n\t" - "cmovb %%edx, %1 \n\t" - : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2) - ); -#endif -#else - //P3:675 athlon:476 - int shift= (uint32_t)(c->range - (0x200 << CABAC_BITS))>>31; - c->range<<= shift; - c->low <<= shift; -#endif - if(!(c->low & CABAC_MASK)) - refill(c); -} - -static int get_cabac(CABACContext *c, uint8_t * const state){ - //FIXME gcc generates duplicate load/stores for c->low and c->range -#ifdef ARCH_X86 - int bit; - -#define LOW "0" -#define RANGE "4" -#define LPS_RANGE "12" -#define LPS_STATE "12+2*66*4" -#define MPS_STATE "12+2*66*4+2*65" -#define BYTESTART "12+2*66*4+4*65" -#define BYTE "16+2*66*4+4*65" -#define BYTEEND "20+2*66*4+4*65" - - asm volatile( - "movzbl (%1), %%eax \n\t" - "movl "RANGE "(%2), %%ebx \n\t" - "movl "RANGE "(%2), %%edx \n\t" - "shrl $23, %%ebx \n\t" - "leal "LPS_RANGE"(%2, %%eax, 4), %%esi \n\t" - "movzbl (%%ebx, %%esi), %%esi \n\t" - "shll $17, %%esi \n\t" - "movl "LOW "(%2), %%ebx \n\t" -//eax:state ebx:low, edx:range, esi:RangeLPS - "subl %%esi, %%edx \n\t" - "cmpl %%edx, %%ebx \n\t" - " ja 1f \n\t" - "cmp $0x2000000, %%edx \n\t" //FIXME avoidable - "setb %%cl \n\t" - "shl %%cl, %%edx \n\t" - "shl %%cl, %%ebx \n\t" - "movb "MPS_STATE"(%2, %%eax), %%cl \n\t" - "movb %%cl, (%1) \n\t" -//eax:state ebx:low, edx:range, esi:RangeLPS - "test %%bx, %%bx \n\t" - " jnz 2f \n\t" - "movl "BYTE "(%2), %%esi \n\t" - "subl $0xFFFF, %%ebx \n\t" - "movzwl (%%esi), %%ecx \n\t" - "bswap %%ecx \n\t" - "shrl $15, %%ecx \n\t" - "addl $2, %%esi \n\t" - "addl %%ecx, %%ebx \n\t" - "movl %%esi, "BYTE "(%2) \n\t" - "jmp 2f \n\t" - "1: \n\t" -//eax:state ebx:low, edx:range, esi:RangeLPS - "subl %%edx, %%ebx \n\t" - "movl %%esi, %%edx \n\t" - "shr $19, %%esi \n\t" - "movb " MANGLE(ff_h264_norm_shift) "(%%esi), %%cl \n\t" - "shll %%cl, %%ebx \n\t" - "shll %%cl, %%edx \n\t" - "movb "LPS_STATE"(%2, %%eax), %%cl \n\t" - "movb %%cl, (%1) \n\t" - "incl %%eax \n\t" - "test %%bx, %%bx \n\t" - " jnz 2f \n\t" - - "movl "BYTE "(%2), %%ecx \n\t" - "movzwl (%%ecx), %%esi \n\t" - "bswap %%esi \n\t" - "shrl $15, %%esi \n\t" - "subl $0xFFFF, %%esi \n\t" - "addl $2, %%ecx \n\t" - "movl %%ecx, "BYTE "(%2) \n\t" - - "leal -1(%%ebx), %%ecx \n\t" - "xorl %%ebx, %%ecx \n\t" - "shrl $17, %%ecx \n\t" - "movb " MANGLE(ff_h264_norm_shift) "(%%ecx), %%cl \n\t" - "neg %%cl \n\t" - "add $7, %%cl \n\t" - - "shll %%cl , %%esi \n\t" - "addl %%esi, %%ebx \n\t" - "2: \n\t" - "movl %%edx, "RANGE "(%2) \n\t" - "movl %%ebx, "LOW "(%2) \n\t" - "andl $1, %%eax \n\t" - - :"=&a"(bit) //FIXME this is fragile gcc either runs out of registers or misscompiles it (for example if "+a"(bit) or "+m"(*state) is used - :"r"(state), "r"(c) - : "%ecx", "%ebx", "%edx", "%esi" - ); -#else - int s = *state; - int RangeLPS= c->lps_range[s][c->range>>(CABAC_BITS+7)]<<(CABAC_BITS+1); - int bit, lps_mask attribute_unused; - - c->range -= RangeLPS; -#if 1 - if(c->low < c->range){ - bit= s&1; - *state= c->mps_state[s]; - renorm_cabac_decoder_once(c); - }else{ - bit= ff_h264_norm_shift[RangeLPS>>19]; - c->low -= c->range; - *state= c->lps_state[s]; - c->range = RangeLPS<low <<= bit; - bit= (s&1)^1; - - if(!(c->low & 0xFFFF)){ - refill2(c); - } - } -#else - lps_mask= (c->range - c->low)>>31; - - c->low -= c->range & lps_mask; - c->range += (RangeLPS - c->range) & lps_mask; - - bit= (s^lps_mask)&1; - *state= c->mps_state[s - (130&lps_mask)]; - - lps_mask= ff_h264_norm_shift[c->range>>(CABAC_BITS+3)]; - c->range<<= lps_mask; - c->low <<= lps_mask; - if(!(c->low & CABAC_MASK)) - refill2(c); -#endif -#endif - return bit; -} - -static int get_cabac_bypass(CABACContext *c){ - c->low += c->low; - - if(!(c->low & CABAC_MASK)) - refill(c); - - if(c->low < c->range){ - return 0; - }else{ - c->low -= c->range; - return 1; - } -} - -/** - * - * @return the number of bytes read or 0 if no end - */ -static int get_cabac_terminate(CABACContext *c){ - c->range -= 4<low < c->range){ - renorm_cabac_decoder_once(c); - return 0; - }else{ - return c->bytestream - c->bytestream_start; - } -} - -/** - * get (truncated) unnary binarization. - */ -static int get_cabac_u(CABACContext *c, uint8_t * state, int max, int max_index, int truncated){ - int i; - - for(i=0; i>=1){ - v+= v + get_cabac_bypass(c); - } - i += v; +void ff_init_cabac_states(void); - if(is_signed && get_cabac_bypass(c)){ - return -i; - }else - return i; -} +#endif /* AVCODEC_CABAC_H */