FFmpeg/libavcodec/dcamath.h
Alexandra Hájková 85990140e7 dca: Add math helpers.
They will be used by the integer core decoder.
2015-12-23 11:50:08 +01:00

43 lines
1.3 KiB
C

/*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/common.h"
// clip a signed integer into the (-2^23), (2^23-1) range
static inline int dca_clip23(int a)
{
return av_clip_intp2(a, 23);
}
static inline int32_t dca_norm(int64_t a, int bits)
{
if (bits > 0)
return (int32_t)((a + (INT64_C(1) << (bits - 1))) >> bits);
else
return (int32_t)a;
}
static inline int64_t dca_round(int64_t a, int bits)
{
if (bits > 0)
return (a + (INT64_C(1) << (bits - 1))) & ~((INT64_C(1) << bits) - 1);
else
return a;
}