MCPcopy Create free account
hub / github.com/FFmpeg/FFmpeg / ff_init_float2half_tables

Function ff_init_float2half_tables

libavutil/float2half.c:21–55  ·  view source on GitHub ↗

Source from the content-addressed store, hash-verified

19#include "libavutil/float2half.h"
20
21void ff_init_float2half_tables(Float2HalfTables *t)
22{
23#if !HAVE_FAST_FLOAT16
24 for (int i = 0; i < 256; i++) {
25 int e = i - 127;
26
27 if (e < -24) { // Very small numbers map to zero
28 t->basetable[i|0x000] = 0x0000;
29 t->basetable[i|0x100] = 0x8000;
30 t->shifttable[i|0x000] = 24;
31 t->shifttable[i|0x100] = 24;
32 } else if (e < -14) { // Small numbers map to denorms
33 t->basetable[i|0x000] = (0x0400>>(-e-14));
34 t->basetable[i|0x100] = (0x0400>>(-e-14)) | 0x8000;
35 t->shifttable[i|0x000] = -e-1;
36 t->shifttable[i|0x100] = -e-1;
37 } else if (e <= 15) { // Normal numbers just lose precision
38 t->basetable[i|0x000] = ((e + 15) << 10);
39 t->basetable[i|0x100] = ((e + 15) << 10) | 0x8000;
40 t->shifttable[i|0x000] = 13;
41 t->shifttable[i|0x100] = 13;
42 } else if (e < 128) { // Large numbers map to Infinity
43 t->basetable[i|0x000] = 0x7C00;
44 t->basetable[i|0x100] = 0xFC00;
45 t->shifttable[i|0x000] = 24;
46 t->shifttable[i|0x100] = 24;
47 } else { // Infinity and NaN's stay Infinity and NaN's
48 t->basetable[i|0x000] = 0x7C00;
49 t->basetable[i|0x100] = 0xFC00;
50 t->shifttable[i|0x000] = 13;
51 t->shifttable[i|0x100] = 13;
52 }
53 }
54#endif
55}

Callers 3

decode_initFunction · 0.85
phm_enc_initFunction · 0.85
encode_initFunction · 0.85

Calls

no outgoing calls

Tested by

no test coverage detected