libavutil/half2float.h

   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #ifndef AVUTIL_HALF2FLOAT_H
  20 #define AVUTIL_HALF2FLOAT_H
  21
  22 #include <stdint.h>
  23 #include "intfloat.h"
  24
  25 #include "config.h"
  26
  27 typedef struct Half2FloatTables {
  28 #if HAVE_FAST_FLOAT16
  29     uint8_t dummy;
  30 #else
  31     uint32_t mantissatable[3072];
  32     uint32_t exponenttable[64];
  33     uint16_t offsettable[64];
  34 #endif
  35 } Half2FloatTables;
  36
  37 void ff_init_half2float_tables(Half2FloatTables *t);
  38
  39 static inline uint32_t half2float(uint16_t h, const Half2FloatTables *t)
  40 {
  41 #if HAVE_FAST_FLOAT16
  42     union {
  43         _Float16 f;
  44         uint16_t i;
  45     } u;
  46     u.i = h;
  47     return av_float2int(u.f);
  48 #else
  49     uint32_t f;
  50
  51     f = t->mantissatable[t->offsettable[h >> 10] + (h & 0x3ff)] + t->exponenttable[h >> 10];
  52
  53     return f;
  54 #endif
  55 }
  56
  57 #endif /* AVUTIL_HALF2FLOAT_H */