trunk/rdesktop/rdpsnd_dsp.c

/*
   rdesktop: A Remote Desktop Protocol client.
   Sound DSP routines
   Copyright (C) Michael Gernoth 2006

   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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "rdesktop.h"
#include "rdpsnd.h"
#include "rdpsnd_dsp.h"

#define MAX_VOLUME 65535

static uint16 softvol_left = MAX_VOLUME;
static uint16 softvol_right = MAX_VOLUME;

void
rdpsnd_dsp_softvol_set(uint16 left, uint16 right)
{
        softvol_left = left;
        softvol_right = right;
        DEBUG(("rdpsnd_dsp_softvol_set: left: %u, right: %u\n", left, right));
}

inline void
rdpsnd_dsp_softvol(unsigned char *buffer, unsigned int size, WAVEFORMATEX * format)
{
        unsigned int factor_left, factor_right;
        unsigned char *posin = buffer;
        unsigned char *posout = buffer;

        if ((softvol_left == MAX_VOLUME) && (softvol_right == MAX_VOLUME))
                return;

        factor_left = (softvol_left * 256) / 65535;
        factor_right = (softvol_right * 256) / 65535;

        if (format->nChannels == 1)
        {
                factor_left = factor_right = (factor_left + factor_right) / 2;
        }

        if (format->wBitsPerSample == 8)
        {
                char val;

                while (posout < buffer + size)
                {
                        /* Left */
                        val = *posin++;
                        val = (val * factor_left) >> 8;
                        *posout++ = val;

                        /* Right */
                        val = *posin++;
                        val = (val * factor_right) >> 8;
                        *posout++ = val;
                }
        }
        else
        {
                short val;

                while (posout < buffer + size)
                {
                        /* Left */
                        val = *posin++;
                        val |= *posin++ << 8;
                        val = (val * factor_left) >> 8;
                        *posout++ = val & 0xff;
                        *posout++ = val >> 8;

                        /* Right */
                        val = *posin++;
                        val |= *posin++ << 8;
                        val = (val * factor_right) >> 8;
                        *posout++ = val & 0xff;
                        *posout++ = val >> 8;
                }
        }

        DEBUG(("using softvol with shifts left: %d, right: %d (%d/%d)\n", factor_left, factor_right,
               format->wBitsPerSample, format->nChannels));
}

unsigned char *
rdpsnd_dsp_process(unsigned char *inbuffer, unsigned int size, struct audio_driver *current_driver,
                   WAVEFORMATEX * format)
{
        unsigned char *outbuffer;

        outbuffer = xmalloc(size);

        memcpy(outbuffer, inbuffer, size);

        /* Software volume control */
        if (current_driver->wave_out_volume == rdpsnd_dsp_softvol_set)
        {
                rdpsnd_dsp_softvol(outbuffer, size, format);
        }

        return outbuffer;
}
1	stargo	1258	/*
2			rdesktop: A Remote Desktop Protocol client.
3			Sound DSP routines
4			Copyright (C) Michael Gernoth 2006
5
6			This program is free software; you can redistribute it and/or modify
7			it under the terms of the GNU General Public License as published by
8			the Free Software Foundation; either version 2 of the License, or
9			(at your option) any later version.
10
11			This program is distributed in the hope that it will be useful,
12			but WITHOUT ANY WARRANTY; without even the implied warranty of
13			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			GNU General Public License for more details.
15
16			You should have received a copy of the GNU General Public License
17			along with this program; if not, write to the Free Software
18			Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19			*/
20
21			#include "rdesktop.h"
22			#include "rdpsnd.h"
23			#include "rdpsnd_dsp.h"
24
25			#define MAX_VOLUME 65535
26
27			static uint16 softvol_left = MAX_VOLUME;
28			static uint16 softvol_right = MAX_VOLUME;
29
30			void
31			rdpsnd_dsp_softvol_set(uint16 left, uint16 right)
32			{
33			softvol_left = left;
34			softvol_right = right;
35			DEBUG(("rdpsnd_dsp_softvol_set: left: %u, right: %u\n", left, right));
36			}
37
38			inline void
39	stargo	1259	rdpsnd_dsp_softvol(unsigned char buffer, unsigned int size, WAVEFORMATEX format)
40	stargo	1258	{
41			unsigned int factor_left, factor_right;
42	stargo	1259	unsigned char *posin = buffer;
43			unsigned char *posout = buffer;
44	stargo	1258
45	stargo	1259	if ((softvol_left == MAX_VOLUME) && (softvol_right == MAX_VOLUME))
46			return;
47
48	stargo	1258	factor_left = (softvol_left * 256) / 65535;
49			factor_right = (softvol_right * 256) / 65535;
50
51			if (format->nChannels == 1)
52			{
53			factor_left = factor_right = (factor_left + factor_right) / 2;
54			}
55
56			if (format->wBitsPerSample == 8)
57			{
58			char val;
59
60	stargo	1259	while (posout < buffer + size)
61	stargo	1258	{
62			/* Left */
63			val = *posin++;
64			val = (val * factor_left) >> 8;
65			*posout++ = val;
66
67			/* Right */
68			val = *posin++;
69			val = (val * factor_right) >> 8;
70			*posout++ = val;
71			}
72			}
73			else
74			{
75			short val;
76
77	stargo	1259	while (posout < buffer + size)
78	stargo	1258	{
79			/* Left */
80			val = *posin++;
81			val \|= *posin++ << 8;
82			val = (val * factor_left) >> 8;
83			*posout++ = val & 0xff;
84			*posout++ = val >> 8;
85
86			/* Right */
87			val = *posin++;
88			val \|= *posin++ << 8;
89			val = (val * factor_right) >> 8;
90			*posout++ = val & 0xff;
91			*posout++ = val >> 8;
92			}
93			}
94
95			DEBUG(("using softvol with shifts left: %d, right: %d (%d/%d)\n", factor_left, factor_right,
96			format->wBitsPerSample, format->nChannels));
97			}
98
99			unsigned char *
100			rdpsnd_dsp_process(unsigned char inbuffer, unsigned int size, struct audio_driver current_driver,
101			WAVEFORMATEX * format)
102			{
103			unsigned char *outbuffer;
104
105			outbuffer = xmalloc(size);
106
107	stargo	1259	memcpy(outbuffer, inbuffer, size);
108
109	stargo	1258	/* Software volume control */
110			if (current_driver->wave_out_volume == rdpsnd_dsp_softvol_set)
111			{
112	stargo	1259	rdpsnd_dsp_softvol(outbuffer, size, format);
113	stargo	1258	}
114
115			return outbuffer;
116			}