1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
// this code is based on a52dec/libao/audio_out_oss.c
// AltiVec support Copyright (c) 2004 Romain Dolbeau <romain@dolbeau.org>
#ifndef SYS_DARWIN
#include <altivec.h>
#endif
const vector signed int magic = {0x43c00000,0x43c00000,0x43c00000,0x43c00000};
static inline vector signed short convert16_altivec(vector signed int v1, vector signed int v2)
{
register vector signed short result;
v1 = vec_subs(v1, magic);
v2 = vec_subs(v2, magic);
result = vec_packs(v1, v2);
return result;
}
static int a52_resample_STEREO_to_2_altivec(float * _f, int16_t * s16){
#if 0
int i;
int32_t * f = (int32_t *) _f;
for (i = 0; i < 256; i++) {
s16[2*i] = convert (f[i]);
s16[2*i+1] = convert (f[i+256]);
}
return 2*256;
#else
int i = 0;
int32_t * f = (int32_t *) _f;
register vector signed int f0, f4, f256, f260;
register vector signed short reven, rodd, r0, r1;
for (i = 0; i < 256; i+= 8) {
f0 = vec_ld(0, f);
f4 = vec_ld(16, f);
f256 = vec_ld(1024, f);
f260 = vec_ld(1040, f);
reven = convert16_altivec(f0, f4);
rodd = convert16_altivec(f256, f260);
r0 = vec_mergeh(reven, rodd);
r1 = vec_mergel(reven, rodd);
vec_st(r0, 0, s16);
vec_st(r1, 16, s16);
f += 8;
s16 += 16;
}
return(2*256);
#endif
}
static void* a52_resample_altivec(int flags, int ch){
fprintf(stderr, "Checking for AltiVec resampler : 0x%08x, %d\n", flags, ch);
switch (flags) {
case A52_CHANNEL:
case A52_STEREO:
case A52_DOLBY:
if(ch==2) return a52_resample_STEREO_to_2_altivec;
break;
default:
fprintf(stderr, "Unsupported flags: 0x%08x (%d channels)\n", flags, ch);
break;
}
return NULL;
}
|
