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test/pcm.c: Generic linear PCM support

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- Fix the support of non-native endianness
- Conversion for unsigned formats
- Only allow linear formats

Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2009-07-06 08:42:18 +02:00
parent 3d0843e8ce
commit 184301ae4c
1 changed files with 19 additions and 11 deletions
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30
test/pcm.c
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@ -37,11 +37,13 @@ static void generate_sine(const snd_pcm_channel_area_t *areas,
unsigned char *samples[channels];
int steps[channels];
unsigned int chn;
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
int bps = snd_pcm_format_width(format) / 8; /* bytes per sample */
int format_bits = snd_pcm_format_width(format);
unsigned int maxval = (1 << (format_bits - 1)) - 1;
int bps = format_bits / 8; /* bytes per sample */
int phys_bps = snd_pcm_format_physical_width(format) / 8;
int big_endian = snd_pcm_format_big_endian(format) == 1;
int to_unsigned = snd_pcm_format_unsigned(format) == 1;
/* verify and prepare the contents of areas */
for (chn = 0; chn < channels; chn++) {
if ((areas[chn].first % 8) != 0) {
@ -60,15 +62,16 @@ static void generate_sine(const snd_pcm_channel_area_t *areas,
while (count-- > 0) {
int res, i;
res = sin(phase) * maxval;
if (to_unsigned)
res ^= 1U << (format_bits - 1);
for (chn = 0; chn < channels; chn++) {
/* Generate data in native endian format */
for (i = 0; i < bps; i++) {
#if (__BYTE_ORDER == __BIG_ENDIAN)
*(samples[chn] + phys_bps - 1 - i) = (res >> i * 8) & 0xff;
#else
*(samples[chn] + i) = (res >> i * 8) & 0xff;
#endif
if (big_endian) {
for (i = 0; i < bps; i++)
*(samples[chn] + phys_bps - 1 - i) = (res >> i * 8) & 0xff;
} else {
for (i = 0; i < bps; i++)
*(samples[chn] + i) = (res >> i * 8) & 0xff;
}
samples[chn] += steps[chn];
}
@ -830,6 +833,11 @@ int main(int argc, char *argv[])
}
if (format == SND_PCM_FORMAT_LAST)
format = SND_PCM_FORMAT_S16;
if (!snd_pcm_format_linear(format)) {
printf("Invalid (non-linear) format %s\n",
optarg);
return 1;
}
break;
case 'v':
verbose = 1;