mirror/mpv
0
0
Fork 0
mirror of https://github.com/mpv-player/mpv.git synced 2024-09-20 20:03:10 +02:00
Code

Handle playback of sample rates not supported by the sun audio hardware.

Browse Source 
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@7657 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
jkeil 2002-10-07 18:42:31 +00:00
parent 9ebb08f13e
commit 34b4b61bea
1 changed files with 216 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

235
libao2/ao_sun.c
View File

@ -10,6 +10,12 @@
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/audioio.h>
#ifdef AUDIO_SWFEATURE_MIXER /* solaris8 or newer? */
# define HAVE_SYS_MIXER_H 1
#endif
#if HAVE_SYS_MIXER_H
# include <sys/mixer.h>
#endif
#ifdef __svr4__
#include <stropts.h>
#endif
@ -208,6 +214,149 @@ error:
return rtsc_ok;
}
// match the requested sample rate |sample_rate| against the
// sample rates supported by the audio device |dev|. Return
// a supported sample rate, if that sample rate is close to
// (< 1% difference) the requested rate; return 0 otherwise.
#define MAX_RATE_ERR 1
static unsigned
find_close_samplerate_match(int dev, unsigned sample_rate)
{
#if HAVE_SYS_MIXER_H
am_sample_rates_t *sr;
unsigned i, num, err, best_err, best_rate;
for (num = 16; num < 1024; num *= 2) {
sr = malloc(AUDIO_MIXER_SAMP_RATES_STRUCT_SIZE(num));
if (!sr)
return 0;
sr->type = AUDIO_PLAY;
sr->flags = 0;
sr->num_samp_rates = num;
if (ioctl(dev, AUDIO_MIXER_GET_SAMPLE_RATES, sr)) {
free(sr);
return 0;
}
if (sr->num_samp_rates <= num)
break;
free(sr);
}
if (sr->flags & MIXER_SR_LIMITS) {
/*
* HW can playback any rate between
* sr->samp_rates[0] .. sr->samp_rates[1]
*/
free(sr);
return 0;
} else {
/* HW supports fixed sample rates only */
best_err = 65535;
best_rate = 0;
for (i = 0; i < sr->num_samp_rates; i++) {
err = abs(sr->samp_rates[i] - sample_rate);
if (err == 0) {
/*
* exact supported sample rate match, no need to
* retry something else
*/
best_rate = 0;
break;
}
if (err < best_err) {
best_err = err;
best_rate = sr->samp_rates[i];
}
}
free(sr);
if (best_rate > 0 && (100/MAX_RATE_ERR)*best_err < sample_rate) {
/* found a supported sample rate with <1% error? */
return best_rate;
}
return 0;
}
#else /* old audioio driver, cannot return list of supported rates */
/* XXX: hardcoded sample rates */
unsigned i, err;
unsigned audiocs_rates[] = {
5510, 6620, 8000, 9600, 11025, 16000, 18900, 22050,
27420, 32000, 33075, 37800, 44100, 48000, 0
};
for (i = 0; audiocs_rates[i]; i++) {
err = abs(audiocs_rates[i] - sample_rate);
if (err == 0) {
/*
* exact supported sample rate match, no need to
* retry something elise
*/
return 0;
}
if ((100/MAX_RATE_ERR)*err < audiocs_rates[i]) {
/* <1% error? */
return audiocs_rates[i];
}
}
return 0;
#endif
}
// return the highest sample rate supported by audio device |dev|.
static unsigned
find_highest_samplerate(int dev)
{
#if HAVE_SYS_MIXER_H
am_sample_rates_t *sr;
unsigned i, num, max_rate;
for (num = 16; num < 1024; num *= 2) {
sr = malloc(AUDIO_MIXER_SAMP_RATES_STRUCT_SIZE(num));
if (!sr)
return 0;
sr->type = AUDIO_PLAY;
sr->flags = 0;
sr->num_samp_rates = num;
if (ioctl(dev, AUDIO_MIXER_GET_SAMPLE_RATES, sr)) {
free(sr);
return 0;
}
if (sr->num_samp_rates <= num)
break;
free(sr);
}
if (sr->flags & MIXER_SR_LIMITS) {
/*
* HW can playback any rate between
* sr->samp_rates[0] .. sr->samp_rates[1]
*/
max_rate = sr->samp_rates[1];
} else {
/* HW supports fixed sample rates only */
max_rate = 0;
for (i = 0; i < sr->num_samp_rates; i++) {
if (sr->samp_rates[i] > max_rate)
max_rate = sr->samp_rates[i];
}
}
free(sr);
return max_rate;
#else /* old audioio driver, cannot return list of supported rates */
return 44100; /* should be supported even on old ISA SB cards */
#endif
}
static void setup_device_paths()
{
if (audio_dev == NULL) {
@ -236,7 +385,7 @@ static int control(int cmd,int arg){
return CONTROL_TRUE;
case AOCONTROL_GET_VOLUME:
{
int fd,v,cmd,devs;
int fd;
if ( !sun_mixer_device ) /* control function is used before init? */
setup_device_paths();
@ -267,7 +416,7 @@ static int control(int cmd,int arg){
case AOCONTROL_SET_VOLUME:
{
ao_control_vol_t *vol = (ao_control_vol_t *)arg;
int fd,v,cmd,devs;
int fd;
if ( !sun_mixer_device ) /* control function is used before init? */
setup_device_paths();
@ -304,6 +453,7 @@ static int control(int cmd,int arg){
static int init(int rate,int channels,int format,int flags){
audio_info_t info;
int pass;
int ok;
setup_device_paths();
@ -324,25 +474,73 @@ static int init(int rate,int channels,int format,int flags){
ioctl(audio_fd, AUDIO_DRAIN, 0);
AUDIO_INITINFO(&info);
info.play.encoding = oss2sunfmt(ao_data.format = format);
info.play.precision =
(format==AFMT_S16_LE || format==AFMT_S16_BE
? AUDIO_PRECISION_16
: AUDIO_PRECISION_8);
info.play.channels = ao_data.channels = channels;
info.play.sample_rate = ao_data.samplerate = rate;
convert_u8_s8 = 0;
ok = ioctl(audio_fd, AUDIO_SETINFO, &info) >= 0;
if (!ok && info.play.encoding == AUDIO_ENCODING_LINEAR8) {
/* sun audiocs hardware does not support U8 format, try S8... */
info.play.encoding = AUDIO_ENCODING_LINEAR;
ok = ioctl(audio_fd, AUDIO_SETINFO, &info) >= 0;
if (ok) {
/* we must perform software U8 -> S8 conversion */
for (ok = pass = 0; pass <= 5; pass++) { /* pass 6&7 not useful */
AUDIO_INITINFO(&info);
info.play.encoding = oss2sunfmt(ao_data.format = format);
info.play.precision =
(format==AFMT_S16_LE || format==AFMT_S16_BE
? AUDIO_PRECISION_16
: AUDIO_PRECISION_8);
info.play.channels = ao_data.channels = channels;
info.play.sample_rate = ao_data.samplerate = rate;
convert_u8_s8 = 0;
if (pass & 1) {
/*
* on some sun audio drivers, 8-bit unsigned LINEAR8 encoding is
* not supported, but 8-bit signed encoding is.
*
* Try S8, and if it works, use our own U8->S8 conversion before
* sending the samples to the sound driver.
*/
if (info.play.encoding != AUDIO_ENCODING_LINEAR8)
continue;
info.play.encoding = AUDIO_ENCODING_LINEAR;
convert_u8_s8 = 1;
}
if (pass & 2) {
/*
* on some sun audio drivers, only certain fixed sample rates are
* supported.
*
* In case the requested sample rate is very close to one of the
* supported rates, use the fixed supported rate instead.
*/
if (!(info.play.sample_rate =
find_close_samplerate_match(audio_fd, rate)))
continue;
/*
* I'm not returning the correct sample rate in
* |ao_data.samplerate|, to avoid software resampling.
*
* ao_data.samplerate = info.play.sample_rate;
*/
}
if (pass & 4) {
/* like "pass & 2", but use the highest supported sample rate */
if (!(info.play.sample_rate
= ao_data.samplerate
= find_highest_samplerate(audio_fd)))
continue;
}
ok = ioctl(audio_fd, AUDIO_SETINFO, &info) >= 0;
if (ok) {
/* audio format accepted by audio driver */
break;
}
/*
* format not supported?
* retry with different encoding and/or sample rate
*/
}
if (!ok) {
printf("audio_setup: your card doesn't support %d channel, %s, %d Hz samplerate\n",
channels, audio_out_format_name(format), rate);
@ -461,7 +659,6 @@ static void audio_resume()
// return: how many bytes can be played without blocking
static int get_space(){
int playsize = ao_data.outburst;
audio_info_t info;
// check buffer