ffmpeg/libavcodec/tests/rangecoder.c

103 lines
3.3 KiB
C

/*
* 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 <stdint.h>
#include <string.h>
#include "libavutil/lfg.h"
#include "libavutil/log.h"
#include "libavcodec/rangecoder.h"
#define SIZE 1240
/**
* Check if at the current position there is a valid looking termination
* @param version version 0 requires the decoder to know the data size in bytes
* version 1 needs about 1 bit more space but does not need to
* carry the size from encoder to decoder
* @returns negative AVERROR code on error or non negative.
*/
static int rac_check_termination(RangeCoder *c, int version)
{
if (version == 1) {
RangeCoder tmp = *c;
get_rac(c, (uint8_t[]) { 129 });
if (c->bytestream == tmp.bytestream && c->bytestream > c->bytestream_start)
tmp.low -= *--tmp.bytestream;
tmp.bytestream_end = tmp.bytestream;
if (get_rac(&tmp, (uint8_t[]) { 129 }))
return AVERROR_INVALIDDATA;
} else {
if (c->bytestream_end != c->bytestream)
return AVERROR_INVALIDDATA;
}
return 0;
}
int main(void)
{
RangeCoder c;
uint8_t b[9 * SIZE] = {0};
uint8_t r[9 * SIZE];
int i, p, actual_length, version;
uint8_t state[10];
AVLFG prng;
av_lfg_init(&prng, 1);
for (version = 0; version < 2; version++) {
for (p = 0; p< 1024; p++) {
ff_init_range_encoder(&c, b, SIZE);
ff_build_rac_states(&c, (1LL << 32) / 20, 128 + 64 + 32 + 16);
memset(state, 128, sizeof(state));
for (i = 0; i < SIZE; i++)
r[i] = av_lfg_get(&prng) % 7;
for (i = 0; i < SIZE; i++)
put_rac(&c, state, r[i] & 1);
actual_length = ff_rac_terminate(&c, version);
ff_init_range_decoder(&c, b, version ? SIZE : actual_length);
memset(state, 128, sizeof(state));
for (i = 0; i < SIZE; i++)
if ((r[i] & 1) != get_rac(&c, state)) {
av_log(NULL, AV_LOG_ERROR, "rac failure at %d pass %d version %d\n", i, p, version);
return 1;
}
if (rac_check_termination(&c, version) < 0) {
av_log(NULL, AV_LOG_ERROR, "rac failure at termination pass %d version %d\n", p, version);
return 1;
}
if (c.bytestream - c.bytestream_start - actual_length != version) {
av_log(NULL, AV_LOG_ERROR, "rac failure at pass %d version %d\n", p, version);
return 1;
}
}
}
return 0;
}