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
75
76
77
78
79
80
|
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "ad_internal.h"
static ad_info_t info =
{
"Uncompressed PCM audio decoder",
"pcm",
AFM_PCM,
"Nick Kurshev",
"A'rpi",
""
};
LIBAD_EXTERN(pcm)
static int init(sh_audio_t *sh_audio)
{
WAVEFORMATEX *h=sh_audio->wf;
sh_audio->i_bps=h->nAvgBytesPerSec;
sh_audio->channels=h->nChannels;
sh_audio->samplerate=h->nSamplesPerSec;
sh_audio->samplesize=(h->wBitsPerSample+7)/8;
switch(sh_audio->format){ /* hardware formats: */
case 0x6: sh_audio->sample_format=AFMT_A_LAW;break;
case 0x7: sh_audio->sample_format=AFMT_MU_LAW;break;
case 0x11: sh_audio->sample_format=AFMT_IMA_ADPCM;break;
case 0x50: sh_audio->sample_format=AFMT_MPEG;break;
/* case 0x2000: sh_audio->sample_format=AFMT_AC3; */
default: if(sh_audio->samplesize!=2) sh_audio->sample_format=AFMT_U8;
}
return 1;
}
static int preinit(sh_audio_t *sh)
{
sh->audio_out_minsize=2048;
return 1;
}
static void uninit(sh_audio_t *sh)
{
}
static int control(sh_audio_t *sh,int cmd,void* arg, ...)
{
int skip;
switch(cmd)
{
case ADCTRL_SKIP_FRAME:
skip=sh->i_bps/16;
skip=skip&(~3);
demux_read_data(sh->ds,NULL,skip);
return CONTROL_TRUE;
}
return CONTROL_UNKNOWN;
}
static int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen)
{
int len=sh_audio->channels*sh_audio->samplesize-1;
len=(minlen+len)&(~len); // sample align
len=demux_read_data(sh_audio->ds,buf,len);
#ifdef WORDS_BIGENDIAN
if(sh_audio->format!=0x736F7774){
#else
if(sh_audio->format==0x736F7774){ // "twos" is swapped byteorder
#endif
int j;
for(j=0;j<len;j+=2){
char x=buf[j];
buf[j]=buf[j+1];
buf[j+1]=x;
}
}
return len;
}
|