aboutsummaryrefslogtreecommitdiffstats
path: root/src/pcm_utils.c
blob: 741cb3d7b9e65dd640c00935cb9d96b2e044e80b (plain) (blame)
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
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/* the Music Player Daemon (MPD)
 * (c)2003-2004 by Warren Dukes (shank@mercury.chem.pitt.edu)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "pcm_utils.h"

#include "mpd_types.h"
#include "log.h"

#include <string.h>
#include <math.h>

void pcm_changeBufferEndianness(char * buffer, int bufferSize, int bits) {
	char temp;

	switch(bits) {
	case 16:
		while(bufferSize) {
			temp = *buffer;
			*buffer = *(buffer+1);
			*(buffer+1) = temp;
			bufferSize-=2;
		}
		break;
	}
}

void pcm_volumeChange(char * buffer, int bufferSize, AudioFormat * format,
		int volume)
{
	mpd_sint32 temp32;
	mpd_sint8 * buffer8 = (mpd_sint8 *)buffer;
	mpd_sint16 * buffer16 = (mpd_sint16 *)buffer;

	if(volume>=1000) return;
	
	if(volume<=0) {
		memset(buffer,0,bufferSize);
		return;
	}

	switch(format->bits) {
	case 16:
		while(bufferSize>0) {
			temp32 = *buffer16;
			temp32*= volume;
			temp32/=1000;
			*buffer16 = temp32>32767 ? 32767 : 
					(temp32<-32768 ? -32768 : temp32);
			buffer16++;
			bufferSize-=2;
		}
		break;
	case 8:
		while(bufferSize>0) {
			temp32 = *buffer8;
			temp32*= volume;
			temp32/=1000;
			*buffer8 = temp32>127 ? 127 : 
					(temp32<-128 ? -128 : temp32);
			buffer8++;
			bufferSize--;
		}
		break;
	default:
		ERROR("%i bits not supported by pcm_volumeChange!\n",
				format->bits);
		exit(EXIT_FAILURE);
	}
}

void pcm_add(char * buffer1, char * buffer2, size_t bufferSize1, 
		size_t bufferSize2, int vol1, int vol2, AudioFormat * format)
{
	mpd_sint32 temp32;
	mpd_sint8 * buffer8_1 = (mpd_sint8 *)buffer1;
	mpd_sint8 * buffer8_2 = (mpd_sint8 *)buffer2;
	mpd_sint16 * buffer16_1 = (mpd_sint16 *)buffer1;
	mpd_sint16 * buffer16_2 = (mpd_sint16 *)buffer2;

	switch(format->bits) {
	case 16:
		while(bufferSize1>0 && bufferSize2>0) {
			temp32 = (vol1*(*buffer16_1)+vol2*(*buffer16_2))/1000;
			*buffer16_1 = temp32>32767 ? 32767 : 
					(temp32<-32768 ? -32768 : temp32);
			buffer16_1++;
			buffer16_2++;
			bufferSize1-=2;
			bufferSize2-=2;
		}
		if(bufferSize2>0) memcpy(buffer16_1,buffer16_2,bufferSize2);
		break;
	case 8:
		while(bufferSize1>0 && bufferSize2>0) {
			temp32 = (vol1*(*buffer8_1)+vol2*(*buffer8_2))/1000;
			*buffer8_1 = temp32>127 ? 127 : 
					(temp32<-128 ? -128 : temp32);
			buffer8_1++;
			buffer8_2++;
			bufferSize1--;
			bufferSize2--;
		}
		if(bufferSize2>0) memcpy(buffer8_1,buffer8_2,bufferSize2);
		break;
	default:
		ERROR("%i bits not supported by pcm_add!\n",format->bits);
		exit(EXIT_FAILURE);
	}
}

void pcm_mix(char * buffer1, char * buffer2, size_t bufferSize1, 
		size_t bufferSize2, AudioFormat * format, float portion1)
{
	int vol1;
	float s = sin(M_PI_2*portion1);
	s*=s;
	
	vol1 = s*1000+0.5;
	vol1 = vol1>1000 ? 1000 : ( vol1<0 ? 0 : vol1 );

	pcm_add(buffer1,buffer2,bufferSize1,bufferSize2,vol1,1000-vol1,format);
}

void pcm_convertAudioFormat(AudioFormat * inFormat, char * inBuffer, size_t
                inSize, AudioFormat * outFormat, char * outBuffer)
{
	abort();

	return;
}

size_t pcm_sizeOfOutputBufferForAudioFormatConversion(AudioFormat * inFormat,
		char * inBuffer, size_t inSize, AudioFormat * outFormat)
{
	abort();

	return 0;
}

/* vim:set shiftwidth=8 tabstop=8 expandtab: */