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Fix VU meter for S24_3 and big-endian

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From: Martin Habets <errandir_news@mph.eclipse.co.uk>

Fixed VU meter calculation for S24_3 format and on big-endian.
This commit is contained in:
Takashi Iwai 2005-10-10 12:52:28 +00:00
parent b8920a79c3
commit 71dd656ef1
1 changed files with 44 additions and 7 deletions
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51
aplay/aplay.c
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@ -43,6 +43,7 @@
#include <sys/uio.h>
#include <sys/time.h>
#include <sys/signal.h>
#include <asm/byteorder.h>
#include "aconfig.h"
#include "gettext.h"
#include "formats.h"
@ -1099,8 +1100,10 @@ static void suspend(void)
static void compute_max_peak(u_char *data, size_t count)
{
signed int val, max, max_peak = 0, perc;
static int run = 0;
size_t ocount = count;
int format_little_endian = snd_pcm_format_little_endian(hwparams.format);
switch (bits_per_sample) {
case 8: {
signed char *valp = (signed char *)data;
@ -1116,12 +1119,39 @@ static void compute_max_peak(u_char *data, size_t count)
case 16: {
signed short *valp = (signed short *)data;
signed short mask = snd_pcm_format_silence_16(hwparams.format);
signed short sval;
count /= 2;
while (count-- > 0) {
val = *valp++ ^ mask;
val = abs(val);
if (format_little_endian)
sval = __le16_to_cpu(*valp);
else sval = __be16_to_cpu(*valp);
sval = abs(sval) ^ mask;
if (max_peak < sval)
max_peak = sval;
valp++;
}
break;
}
case 24: {
unsigned char *valp = data;
signed int mask = snd_pcm_format_silence_32(hwparams.format);
count /= 3;
while (count-- > 0) {
if (format_little_endian) {
val = valp[0] | (valp[1]<<8) | (valp[2]<<16);
} else {
val = (valp[0]<<16) | (valp[1]<<8) | valp[2];
}
/* Correct signed bit in 32-bit value */
if (val & (1<<(bits_per_sample-1))) {
val |= 0xff<<24; /* Negate upper bits too */
}
val = abs(val) ^ mask;
if (max_peak < val)
max_peak = val;
valp += 3;
}
break;
}
@ -1130,20 +1160,27 @@ static void compute_max_peak(u_char *data, size_t count)
signed int mask = snd_pcm_format_silence_32(hwparams.format);
count /= 4;
while (count-- > 0) {
val = *valp++ ^ mask;
val = abs(val);
if (format_little_endian)
val = __le32_to_cpu(*valp);
else val = __be32_to_cpu(*valp);
val = abs(val) ^ mask;
if (max_peak < val)
max_peak = val;
valp++;
}
break;
}
default:
break;
if (run == 0) {
fprintf(stderr, _("Unsupported bit size %d.\n"), bits_per_sample);
run = 1;
}
return;
}
max = 1 << (bits_per_sample-1);
if (max <= 0)
max = 0x7fffffff;
printf(_("Max peak (%li samples): %05i (0x%04x) "), (long)ocount, max_peak, max_peak);
printf(_("Max peak (%li samples): 0x%08x "), (long)ocount, max_peak);
if (bits_per_sample > 16)
perc = max_peak / (max / 100);
else