mirror of https://git.ffmpeg.org/ffmpeg.git
759 lines
24 KiB
C
759 lines
24 KiB
C
/*
|
|
* 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 libavcodec/cabac.h
|
|
* Context Adaptive Binary Arithmetic Coder.
|
|
*/
|
|
|
|
#ifndef AVCODEC_CABAC_H
|
|
#define AVCODEC_CABAC_H
|
|
|
|
#include "put_bits.h"
|
|
|
|
//#undef NDEBUG
|
|
#include <assert.h>
|
|
#include "libavutil/x86_cpu.h"
|
|
|
|
#define CABAC_BITS 16
|
|
#define CABAC_MASK ((1<<CABAC_BITS)-1)
|
|
#define BRANCHLESS_CABAC_DECODER 1
|
|
//#define ARCH_X86_DISABLED 1
|
|
|
|
typedef struct CABACContext{
|
|
int low;
|
|
int range;
|
|
int outstanding_count;
|
|
#ifdef STRICT_LIMITS
|
|
int symCount;
|
|
#endif
|
|
const uint8_t *bytestream_start;
|
|
const uint8_t *bytestream;
|
|
const uint8_t *bytestream_end;
|
|
PutBitContext pb;
|
|
}CABACContext;
|
|
|
|
extern uint8_t ff_h264_mlps_state[4*64];
|
|
extern uint8_t ff_h264_lps_range[4*2*64]; ///< rangeTabLPS
|
|
extern uint8_t ff_h264_mps_state[2*64]; ///< transIdxMPS
|
|
extern uint8_t ff_h264_lps_state[2*64]; ///< transIdxLPS
|
|
extern const uint8_t ff_h264_norm_shift[512];
|
|
|
|
|
|
void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size);
|
|
void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size);
|
|
void ff_init_cabac_states(CABACContext *c);
|
|
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
#ifdef TEST
|
|
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_mps_state[*state];
|
|
}else{
|
|
c->low += c->range - RangeLPS;
|
|
c->range = RangeLPS;
|
|
*state= ff_h264_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<v; i++){
|
|
put_cabac(c, state, 1);
|
|
if(i < max_index) state++;
|
|
}
|
|
if(truncated==0 || v<max)
|
|
put_cabac(c, state, 0);
|
|
#else
|
|
if(v <= max_index){
|
|
for(i=0; i<v; i++){
|
|
put_cabac(c, state+i, 1);
|
|
}
|
|
if(truncated==0 || v<max)
|
|
put_cabac(c, state+i, 0);
|
|
}else{
|
|
for(i=0; i<=max_index; i++){
|
|
put_cabac(c, state+i, 1);
|
|
}
|
|
for(; i<v; i++){
|
|
put_cabac(c, state+max_index, 1);
|
|
}
|
|
if(truncated==0 || v<max)
|
|
put_cabac(c, state+max_index, 0);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* put unary exp golomb k-th order binarization.
|
|
*/
|
|
static void put_cabac_ueg(CABACContext *c, uint8_t * state, int v, int max, int is_signed, int k, int max_index){
|
|
int i;
|
|
|
|
if(v==0)
|
|
put_cabac(c, state, 0);
|
|
else{
|
|
const int sign= v < 0;
|
|
|
|
if(is_signed) v= FFABS(v);
|
|
|
|
if(v<max){
|
|
for(i=0; i<v; i++){
|
|
put_cabac(c, state, 1);
|
|
if(i < max_index) state++;
|
|
}
|
|
|
|
put_cabac(c, state, 0);
|
|
}else{
|
|
int m= 1<<k;
|
|
|
|
for(i=0; i<max; i++){
|
|
put_cabac(c, state, 1);
|
|
if(i < max_index) state++;
|
|
}
|
|
|
|
v -= max;
|
|
while(v >= 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);
|
|
}
|
|
}
|
|
#endif /* TEST */
|
|
|
|
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;
|
|
}
|
|
|
|
#if ! ( ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) )
|
|
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<<i;
|
|
c->bytestream+= CABAC_BITS/8;
|
|
}
|
|
#endif
|
|
|
|
static inline void renorm_cabac_decoder(CABACContext *c){
|
|
while(c->range < 0x100){
|
|
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 -0x100(%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 $0x100, %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 -0x100(%0), %%eax \n\t"
|
|
"cltd \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 $0x100, %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 $0x100, %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 - 0x100)>>31;
|
|
c->range<<= shift;
|
|
c->low <<= shift;
|
|
#endif
|
|
if(!(c->low & CABAC_MASK))
|
|
refill(c);
|
|
}
|
|
|
|
static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const state){
|
|
//FIXME gcc generates duplicate load/stores for c->low and c->range
|
|
#define LOW "0"
|
|
#define RANGE "4"
|
|
#if ARCH_X86_64
|
|
#define BYTESTART "16"
|
|
#define BYTE "24"
|
|
#define BYTEEND "32"
|
|
#else
|
|
#define BYTESTART "12"
|
|
#define BYTE "16"
|
|
#define BYTEEND "20"
|
|
#endif
|
|
#if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS)
|
|
int bit;
|
|
|
|
#ifndef BRANCHLESS_CABAC_DECODER
|
|
__asm__ volatile(
|
|
"movzbl (%1), %0 \n\t"
|
|
"movl "RANGE "(%2), %%ebx \n\t"
|
|
"movl "RANGE "(%2), %%edx \n\t"
|
|
"andl $0xC0, %%ebx \n\t"
|
|
"movzbl "MANGLE(ff_h264_lps_range)"(%0, %%ebx, 2), %%esi\n\t"
|
|
"movl "LOW "(%2), %%ebx \n\t"
|
|
//eax:state ebx:low, edx:range, esi:RangeLPS
|
|
"subl %%esi, %%edx \n\t"
|
|
"movl %%edx, %%ecx \n\t"
|
|
"shll $17, %%ecx \n\t"
|
|
"cmpl %%ecx, %%ebx \n\t"
|
|
" ja 1f \n\t"
|
|
|
|
#if 1
|
|
//athlon:4067 P3:4110
|
|
"lea -0x100(%%edx), %%ecx \n\t"
|
|
"shr $31, %%ecx \n\t"
|
|
"shl %%cl, %%edx \n\t"
|
|
"shl %%cl, %%ebx \n\t"
|
|
#else
|
|
//athlon:4057 P3:4130
|
|
"cmp $0x100, %%edx \n\t" //FIXME avoidable
|
|
"setb %%cl \n\t"
|
|
"shl %%cl, %%edx \n\t"
|
|
"shl %%cl, %%ebx \n\t"
|
|
#endif
|
|
"movzbl "MANGLE(ff_h264_mps_state)"(%0), %%ecx \n\t"
|
|
"movb %%cl, (%1) \n\t"
|
|
//eax:state ebx:low, edx:range, esi:RangeLPS
|
|
"test %%bx, %%bx \n\t"
|
|
" jnz 2f \n\t"
|
|
"mov "BYTE "(%2), %%"REG_S" \n\t"
|
|
"subl $0xFFFF, %%ebx \n\t"
|
|
"movzwl (%%"REG_S"), %%ecx \n\t"
|
|
"bswap %%ecx \n\t"
|
|
"shrl $15, %%ecx \n\t"
|
|
"add $2, %%"REG_S" \n\t"
|
|
"addl %%ecx, %%ebx \n\t"
|
|
"mov %%"REG_S", "BYTE "(%2) \n\t"
|
|
"jmp 2f \n\t"
|
|
"1: \n\t"
|
|
//eax:state ebx:low, edx:range, esi:RangeLPS
|
|
"subl %%ecx, %%ebx \n\t"
|
|
"movl %%esi, %%edx \n\t"
|
|
"movzbl " MANGLE(ff_h264_norm_shift) "(%%esi), %%ecx \n\t"
|
|
"shll %%cl, %%ebx \n\t"
|
|
"shll %%cl, %%edx \n\t"
|
|
"movzbl "MANGLE(ff_h264_lps_state)"(%0), %%ecx \n\t"
|
|
"movb %%cl, (%1) \n\t"
|
|
"add $1, %0 \n\t"
|
|
"test %%bx, %%bx \n\t"
|
|
" jnz 2f \n\t"
|
|
|
|
"mov "BYTE "(%2), %%"REG_c" \n\t"
|
|
"movzwl (%%"REG_c"), %%esi \n\t"
|
|
"bswap %%esi \n\t"
|
|
"shrl $15, %%esi \n\t"
|
|
"subl $0xFFFF, %%esi \n\t"
|
|
"add $2, %%"REG_c" \n\t"
|
|
"mov %%"REG_c", "BYTE "(%2) \n\t"
|
|
|
|
"leal -1(%%ebx), %%ecx \n\t"
|
|
"xorl %%ebx, %%ecx \n\t"
|
|
"shrl $15, %%ecx \n\t"
|
|
"movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"
|
|
"neg %%ecx \n\t"
|
|
"add $7, %%ecx \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"
|
|
:"=&a"(bit) //FIXME this is fragile gcc either runs out of registers or miscompiles it (for example if "+a"(bit) or "+m"(*state) is used
|
|
:"r"(state), "r"(c)
|
|
: "%"REG_c, "%ebx", "%edx", "%"REG_S, "memory"
|
|
);
|
|
bit&=1;
|
|
#else /* BRANCHLESS_CABAC_DECODER */
|
|
|
|
|
|
#if HAVE_FAST_CMOV
|
|
#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
|
|
"mov "tmp" , %%ecx \n\t"\
|
|
"shl $17 , "tmp" \n\t"\
|
|
"cmp "low" , "tmp" \n\t"\
|
|
"cmova %%ecx , "range" \n\t"\
|
|
"sbb %%ecx , %%ecx \n\t"\
|
|
"and %%ecx , "tmp" \n\t"\
|
|
"sub "tmp" , "low" \n\t"\
|
|
"xor %%ecx , "ret" \n\t"
|
|
#else /* HAVE_FAST_CMOV */
|
|
#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
|
|
"mov "tmp" , %%ecx \n\t"\
|
|
"shl $17 , "tmp" \n\t"\
|
|
"sub "low" , "tmp" \n\t"\
|
|
"sar $31 , "tmp" \n\t" /*lps_mask*/\
|
|
"sub %%ecx , "range" \n\t" /*RangeLPS - range*/\
|
|
"and "tmp" , "range" \n\t" /*(RangeLPS - range)&lps_mask*/\
|
|
"add %%ecx , "range" \n\t" /*new range*/\
|
|
"shl $17 , %%ecx \n\t"\
|
|
"and "tmp" , %%ecx \n\t"\
|
|
"sub %%ecx , "low" \n\t"\
|
|
"xor "tmp" , "ret" \n\t"
|
|
#endif /* HAVE_FAST_CMOV */
|
|
|
|
|
|
#define BRANCHLESS_GET_CABAC(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
|
|
"movzbl "statep" , "ret" \n\t"\
|
|
"mov "range" , "tmp" \n\t"\
|
|
"and $0xC0 , "range" \n\t"\
|
|
"movzbl "MANGLE(ff_h264_lps_range)"("ret", "range", 2), "range" \n\t"\
|
|
"sub "range" , "tmp" \n\t"\
|
|
BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
|
|
"movzbl " MANGLE(ff_h264_norm_shift) "("range"), %%ecx \n\t"\
|
|
"shl %%cl , "range" \n\t"\
|
|
"movzbl "MANGLE(ff_h264_mlps_state)"+128("ret"), "tmp" \n\t"\
|
|
"mov "tmpbyte" , "statep" \n\t"\
|
|
"shl %%cl , "low" \n\t"\
|
|
"test "lowword" , "lowword" \n\t"\
|
|
" jnz 1f \n\t"\
|
|
"mov "BYTE"("cabac"), %%"REG_c" \n\t"\
|
|
"movzwl (%%"REG_c") , "tmp" \n\t"\
|
|
"bswap "tmp" \n\t"\
|
|
"shr $15 , "tmp" \n\t"\
|
|
"sub $0xFFFF , "tmp" \n\t"\
|
|
"add $2 , %%"REG_c" \n\t"\
|
|
"mov %%"REG_c" , "BYTE "("cabac") \n\t"\
|
|
"lea -1("low") , %%ecx \n\t"\
|
|
"xor "low" , %%ecx \n\t"\
|
|
"shr $15 , %%ecx \n\t"\
|
|
"movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"\
|
|
"neg %%ecx \n\t"\
|
|
"add $7 , %%ecx \n\t"\
|
|
"shl %%cl , "tmp" \n\t"\
|
|
"add "tmp" , "low" \n\t"\
|
|
"1: \n\t"
|
|
|
|
__asm__ volatile(
|
|
"movl "RANGE "(%2), %%esi \n\t"
|
|
"movl "LOW "(%2), %%ebx \n\t"
|
|
BRANCHLESS_GET_CABAC("%0", "%2", "(%1)", "%%ebx", "%%bx", "%%esi", "%%edx", "%%dl")
|
|
"movl %%esi, "RANGE "(%2) \n\t"
|
|
"movl %%ebx, "LOW "(%2) \n\t"
|
|
|
|
:"=&a"(bit)
|
|
:"r"(state), "r"(c)
|
|
: "%"REG_c, "%ebx", "%edx", "%esi", "memory"
|
|
);
|
|
bit&=1;
|
|
#endif /* BRANCHLESS_CABAC_DECODER */
|
|
#else /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
|
|
int s = *state;
|
|
int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s];
|
|
int bit, lps_mask av_unused;
|
|
|
|
c->range -= RangeLPS;
|
|
#ifndef BRANCHLESS_CABAC_DECODER
|
|
if(c->low < (c->range<<(CABAC_BITS+1))){
|
|
bit= s&1;
|
|
*state= ff_h264_mps_state[s];
|
|
renorm_cabac_decoder_once(c);
|
|
}else{
|
|
bit= ff_h264_norm_shift[RangeLPS];
|
|
c->low -= (c->range<<(CABAC_BITS+1));
|
|
*state= ff_h264_lps_state[s];
|
|
c->range = RangeLPS<<bit;
|
|
c->low <<= bit;
|
|
bit= (s&1)^1;
|
|
|
|
if(!(c->low & CABAC_MASK)){
|
|
refill2(c);
|
|
}
|
|
}
|
|
#else /* BRANCHLESS_CABAC_DECODER */
|
|
lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31;
|
|
|
|
c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask;
|
|
c->range += (RangeLPS - c->range) & lps_mask;
|
|
|
|
s^=lps_mask;
|
|
*state= (ff_h264_mlps_state+128)[s];
|
|
bit= s&1;
|
|
|
|
lps_mask= ff_h264_norm_shift[c->range];
|
|
c->range<<= lps_mask;
|
|
c->low <<= lps_mask;
|
|
if(!(c->low & CABAC_MASK))
|
|
refill2(c);
|
|
#endif /* BRANCHLESS_CABAC_DECODER */
|
|
#endif /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
|
|
return bit;
|
|
}
|
|
|
|
static int av_noinline av_unused get_cabac_noinline(CABACContext *c, uint8_t * const state){
|
|
return get_cabac_inline(c,state);
|
|
}
|
|
|
|
static int av_unused get_cabac(CABACContext *c, uint8_t * const state){
|
|
return get_cabac_inline(c,state);
|
|
}
|
|
|
|
static int av_unused get_cabac_bypass(CABACContext *c){
|
|
#if 0 //not faster
|
|
int bit;
|
|
__asm__ volatile(
|
|
"movl "RANGE "(%1), %%ebx \n\t"
|
|
"movl "LOW "(%1), %%eax \n\t"
|
|
"shl $17, %%ebx \n\t"
|
|
"add %%eax, %%eax \n\t"
|
|
"sub %%ebx, %%eax \n\t"
|
|
"cltd \n\t"
|
|
"and %%edx, %%ebx \n\t"
|
|
"add %%ebx, %%eax \n\t"
|
|
"test %%ax, %%ax \n\t"
|
|
" jnz 1f \n\t"
|
|
"movl "BYTE "(%1), %%"REG_b" \n\t"
|
|
"subl $0xFFFF, %%eax \n\t"
|
|
"movzwl (%%"REG_b"), %%ecx \n\t"
|
|
"bswap %%ecx \n\t"
|
|
"shrl $15, %%ecx \n\t"
|
|
"addl $2, %%"REG_b" \n\t"
|
|
"addl %%ecx, %%eax \n\t"
|
|
"movl %%"REG_b", "BYTE "(%1) \n\t"
|
|
"1: \n\t"
|
|
"movl %%eax, "LOW "(%1) \n\t"
|
|
|
|
:"=&d"(bit)
|
|
:"r"(c)
|
|
: "%eax", "%"REG_b, "%ecx", "memory"
|
|
);
|
|
return bit+1;
|
|
#else
|
|
int range;
|
|
c->low += c->low;
|
|
|
|
if(!(c->low & CABAC_MASK))
|
|
refill(c);
|
|
|
|
range= c->range<<(CABAC_BITS+1);
|
|
if(c->low < range){
|
|
return 0;
|
|
}else{
|
|
c->low -= range;
|
|
return 1;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
|
|
static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){
|
|
#if ARCH_X86 && HAVE_EBX_AVAILABLE
|
|
__asm__ volatile(
|
|
"movl "RANGE "(%1), %%ebx \n\t"
|
|
"movl "LOW "(%1), %%eax \n\t"
|
|
"shl $17, %%ebx \n\t"
|
|
"add %%eax, %%eax \n\t"
|
|
"sub %%ebx, %%eax \n\t"
|
|
"cltd \n\t"
|
|
"and %%edx, %%ebx \n\t"
|
|
"add %%ebx, %%eax \n\t"
|
|
"xor %%edx, %%ecx \n\t"
|
|
"sub %%edx, %%ecx \n\t"
|
|
"test %%ax, %%ax \n\t"
|
|
" jnz 1f \n\t"
|
|
"mov "BYTE "(%1), %%"REG_b" \n\t"
|
|
"subl $0xFFFF, %%eax \n\t"
|
|
"movzwl (%%"REG_b"), %%edx \n\t"
|
|
"bswap %%edx \n\t"
|
|
"shrl $15, %%edx \n\t"
|
|
"add $2, %%"REG_b" \n\t"
|
|
"addl %%edx, %%eax \n\t"
|
|
"mov %%"REG_b", "BYTE "(%1) \n\t"
|
|
"1: \n\t"
|
|
"movl %%eax, "LOW "(%1) \n\t"
|
|
|
|
:"+c"(val)
|
|
:"r"(c)
|
|
: "%eax", "%"REG_b, "%edx", "memory"
|
|
);
|
|
return val;
|
|
#else
|
|
int range, mask;
|
|
c->low += c->low;
|
|
|
|
if(!(c->low & CABAC_MASK))
|
|
refill(c);
|
|
|
|
range= c->range<<(CABAC_BITS+1);
|
|
c->low -= range;
|
|
mask= c->low >> 31;
|
|
range &= mask;
|
|
c->low += range;
|
|
return (val^mask)-mask;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
*
|
|
* @return the number of bytes read or 0 if no end
|
|
*/
|
|
static int av_unused get_cabac_terminate(CABACContext *c){
|
|
c->range -= 2;
|
|
if(c->low < c->range<<(CABAC_BITS+1)){
|
|
renorm_cabac_decoder_once(c);
|
|
return 0;
|
|
}else{
|
|
return c->bytestream - c->bytestream_start;
|
|
}
|
|
}
|
|
|
|
#if 0
|
|
/**
|
|
* Get (truncated) unary binarization.
|
|
*/
|
|
static int get_cabac_u(CABACContext *c, uint8_t * state, int max, int max_index, int truncated){
|
|
int i;
|
|
|
|
for(i=0; i<max; i++){
|
|
if(get_cabac(c, state)==0)
|
|
return i;
|
|
|
|
if(i< max_index) state++;
|
|
}
|
|
|
|
return truncated ? max : -1;
|
|
}
|
|
|
|
/**
|
|
* get unary exp golomb k-th order binarization.
|
|
*/
|
|
static int get_cabac_ueg(CABACContext *c, uint8_t * state, int max, int is_signed, int k, int max_index){
|
|
int i, v;
|
|
int m= 1<<k;
|
|
|
|
if(get_cabac(c, state)==0)
|
|
return 0;
|
|
|
|
if(0 < max_index) state++;
|
|
|
|
for(i=1; i<max; i++){
|
|
if(get_cabac(c, state)==0){
|
|
if(is_signed && get_cabac_bypass(c)){
|
|
return -i;
|
|
}else
|
|
return i;
|
|
}
|
|
|
|
if(i < max_index) state++;
|
|
}
|
|
|
|
while(get_cabac_bypass(c)){
|
|
i+= m;
|
|
m+= m;
|
|
}
|
|
|
|
v=0;
|
|
while(m>>=1){
|
|
v+= v + get_cabac_bypass(c);
|
|
}
|
|
i += v;
|
|
|
|
if(is_signed && get_cabac_bypass(c)){
|
|
return -i;
|
|
}else
|
|
return i;
|
|
}
|
|
#endif /* 0 */
|
|
|
|
#endif /* AVCODEC_CABAC_H */
|