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/*
* Common bit i/o utils
* Copyright (c) 2000, 2001 Fabrice Bellard
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
* Copyright (c) 2010 Loren Merritt
*
* alternative bitstream reader & writer by 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
* bitstream api.
*/
#include <stdint.h>
#include <string.h>
#include "config.h"
#include "libavutil/avassert.h"
#include "libavutil/intreadwrite.h"
#include "put_bits.h"
const uint8_t ff_log2_run[41]={
0, 0, 0, 0, 1, 1, 1, 1,
2, 2, 2, 2, 3, 3, 3, 3,
4, 4, 5, 5, 6, 6, 7, 7,
8, 9,10,11,12,13,14,15,
16,17,18,19,20,21,22,23,
24,
};
void ff_put_string(PutBitContext *pb, const char *string, int terminate_string)
{
while (*string) {
put_bits(pb, 8, *string);
string++;
}
if (terminate_string)
put_bits(pb, 8, 0);
}
void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length)
{
int words = length >> 4;
int bits = length & 15;
int i;
if (length == 0)
return;
av_assert0(length <= put_bits_left(pb));
if (CONFIG_SMALL || words < 16 || put_bits_count(pb) & 7) {
for (i = 0; i < words; i++)
put_bits(pb, 16, AV_RB16(src + 2 * i));
} else {
for (i = 0; put_bits_count(pb) & 31; i++)
put_bits(pb, 8, src[i]);
flush_put_bits(pb);
memcpy(put_bits_ptr(pb), src + i, 2 * words - i);
skip_put_bytes(pb, 2 * words - i);
}
put_bits(pb, bits, AV_RB16(src + 2 * words) >> (16 - bits));
}
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