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/*
* TwoLAME: an optimized MPEG Audio Layer Two encoder
*
* Copyright (C) 2001-2004 Michael Cheng
* Copyright (C) 2004-2006 The TwoLAME Project
*
* This library 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.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id$
*
*/
/* write 1 bit from the bit stream */
static inline void buffer_put1bit(bit_stream * bs, int bit)
{
bs->totbit++;
bs->buf[bs->buf_byte_idx] |= (bit & 0x1) << (bs->buf_bit_idx - 1);
bs->buf_bit_idx--;
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx++;
if (bs->buf_byte_idx >= bs->buf_size) {
// empty_buffer (bs, minimum);
fprintf(stderr, "buffer_put1bit: error. bit_stream buffer needs to be bigger\n");
return;
}
bs->buf[bs->buf_byte_idx] = 0;
}
}
/* write N bits into the bit stream */
static inline void buffer_putbits(bit_stream * bs, unsigned int val, int N)
{
static const int putmask[9] = { 0x0, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff };
register int j = N;
register int k, tmp;
bs->totbit += N;
while (j > 0) {
k = MIN(j, bs->buf_bit_idx);
tmp = val >> (j - k);
bs->buf[bs->buf_byte_idx] |= (tmp & putmask[k]) << (bs->buf_bit_idx - k);
bs->buf_bit_idx -= k;
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx++;
if (bs->buf_byte_idx >= bs->buf_size) {
// empty_buffer (bs, minimum);
fprintf(stderr, "buffer_putbits: error. bit_stream buffer needs to be bigger\n");
return;
}
bs->buf[bs->buf_byte_idx] = 0;
}
j -= k;
}
}
// vim:ts=4:sw=4:nowrap:
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