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/*
* 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
*/
#include "libavcodec/cabac_functions.h"
#include "libavcodec/cabac.c"
#define SIZE 10240
#include "libavutil/lfg.h"
#include "libavcodec/put_bits.h"
typedef struct CABACTestContext {
CABACContext dec;
int outstanding_count;
PutBitContext pb;
} CABACTestContext;
static inline void put_cabac_bit(CABACTestContext *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(CABACTestContext *c)
{
while (c->dec.range < 0x100) {
//FIXME optimize
if (c->dec.low < 0x100) {
put_cabac_bit(c, 0);
} else if (c->dec.low < 0x200) {
c->outstanding_count++;
c->dec.low -= 0x100;
}else{
put_cabac_bit(c, 1);
c->dec.low -= 0x200;
}
c->dec.range += c->dec.range;
c->dec.low += c->dec.low;
}
}
static void put_cabac(CABACTestContext *c, uint8_t * const state, int bit)
{
int RangeLPS = ff_h264_lps_range[2 * (c->dec.range & 0xC0) + *state];
if(bit == ((*state)&1)){
c->dec.range -= RangeLPS;
*state = ff_h264_mlps_state[128 + *state];
}else{
c->dec.low += c->dec.range - RangeLPS;
c->dec.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(CABACTestContext *c, int bit)
{
c->dec.low += c->dec.low;
if(bit){
c->dec.low += c->dec.range;
}
//FIXME optimize
if (c->dec.low < 0x200) {
put_cabac_bit(c, 0);
} else if (c->dec.low < 0x400) {
c->outstanding_count++;
c->dec.low -= 0x200;
}else{
put_cabac_bit(c, 1);
c->dec.low -= 0x400;
}
}
/**
*
* @return the number of bytes written
*/
static int put_cabac_terminate(CABACTestContext *c, int bit)
{
c->dec.range -= 2;
if(!bit){
renorm_cabac_encoder(c);
}else{
c->dec.low += c->dec.range;
c->dec.range = 2;
renorm_cabac_encoder(c);
av_assert0(c->dec.low <= 0x1FF);
put_cabac_bit(c, c->dec.low >> 9);
put_bits(&c->pb, 2, ((c->dec.low >> 7) & 3) | 1);
flush_put_bits(&c->pb); //FIXME FIXME FIXME XXX wrong
}
return put_bytes_count(&c->pb, 1);
}
/**
* @param buf_size size of buf in bits
*/
static void init_cabac_encoder(CABACTestContext *c, uint8_t *buf, int buf_size)
{
init_put_bits(&c->pb, buf, buf_size);
c->dec.low = 0;
c->dec.range = 0x1FE;
c->outstanding_count = 0;
c->pb.bit_left++; //avoids firstBitFlag
}
int main(void){
CABACTestContext c;
uint8_t b[9*SIZE];
uint8_t r[9*SIZE];
int i, ret = 0;
uint8_t state[10]= {0};
AVLFG prng;
av_lfg_init(&prng, 1);
init_cabac_encoder(&c, b, SIZE);
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++){
put_cabac_bypass(&c, r[i]&1);
}
for(i=0; i<SIZE; i++){
put_cabac(&c, state, r[i]&1);
}
i= put_cabac_terminate(&c, 1);
b[i++] = av_lfg_get(&prng);
b[i ] = av_lfg_get(&prng);
ff_init_cabac_decoder(&c.dec, b, SIZE);
memset(state, 0, sizeof(state));
for(i=0; i<SIZE; i++){
if ((r[i] & 1) != get_cabac_bypass(&c.dec)) {
av_log(NULL, AV_LOG_ERROR, "CABAC bypass failure at %d\n", i);
ret = 1;
}
}
for(i=0; i<SIZE; i++){
if ((r[i] & 1) != get_cabac_noinline(&c.dec, state)) {
av_log(NULL, AV_LOG_ERROR, "CABAC failure at %d\n", i);
ret = 1;
}
}
if (!get_cabac_terminate(&c.dec)) {
av_log(NULL, AV_LOG_ERROR, "where's the Terminator?\n");
ret = 1;
}
return ret;
}
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