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|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
#include "common/util.h"
#include "../mixer.h"
#include "sci/include/sci_memory.h"
namespace Sci {
/* Max. number of microseconds in difference allowed between independent audio streams */
#define TIMESTAMP_MAX_ALLOWED_DELTA 2000
/*#define DEBUG 3*/
/* Set DEBUG to one of the following:
** anything -- high-level debugging (feed subscriptions/deletions etc.)
** >= 1 -- rough input and output analysis (once per call)
** >= 2 -- more detailed input analysis (once per call and feed)
** >= 3 -- fully detailed input and output analysis (once per frame and feed)
*/
/*#define DEBUG 0*/
#define MIN_DELTA_OBSERVATIONS 100 /* Number of times the mixer is called before it starts trying to improve latency */
#define MAX_DELTA_OBSERVATIONS 1000000 /* Number of times the mixer is called before we assume we truly understand timing */
static int diagnosed_too_slow = 0;
static volatile int mixer_lock = 0;
/*#define DEBUG_LOCKS*/
#ifdef DEBUG_LOCKS
# define DEBUG_ACQUIRE warning("[ -LOCK -] ACKQ %d: %d", __LINE__, mixer_lock)
# define DEBUG_WAIT warning("[ -LOCK -] WAIT %d: %d", __LINE__, mixer_lock);
# define DEBUG_RELEASE ; warning("[ -LOCK -] REL %d: %d", __LINE__, mixer_lock);
#else
# define DEBUG_ACQUIRE
# define DEBUG_WAIT
# define DEBUG_RELEASE
#endif
#define ACQUIRE_LOCK() ++mixer_lock; while (mixer_lock != 1) { DEBUG_WAIT sci_sched_yield(); } DEBUG_ACQUIRE
#define RELEASE_LOCK() --mixer_lock DEBUG_RELEASE
struct mixer_private {
byte *outbuf; /* Output buffer to write to the PCM device next time */
sfx_timestamp_t outbuf_timestamp; /* Timestamp associated with the output buffer */
int have_outbuf_timestamp; /* Whether we really _have_ an associated timestamp */
byte *writebuf; /* Buffer we're supposed to write to */
gint32 *compbuf_l, *compbuf_r; /* Intermediate buffers for computation */
int lastbuf_len; /* Number of frames stored in the last buffer */
long skew; /* Millisecond relative to which we compute time. This is the millisecond
** part of the first time we emitted sound, to simplify some computations. */
long lsec; /* Last point in time we updated buffers, if any (seconds since the epoch) */
int played_this_second; /* Number of frames emitted so far in second lsec */
int max_delta; /* maximum observed time delta (using 'frames' as a metric unit) */
int delta_observations; /* Number of times we played; confidence measure for max_delta */
/* Pause data */
int paused;
};
#define P ((struct mixer_private *)(self->private_bits))
static int
mix_init(sfx_pcm_mixer_t *self, sfx_pcm_device_t *device) {
self->dev = device;
self->private_bits /* = P */ = sci_malloc(sizeof(struct mixer_private));
P->outbuf = P->writebuf = NULL;
P->lastbuf_len = 0;
P->compbuf_l = (gint32*)sci_malloc(sizeof(gint32) * device->buf_size);
P->compbuf_r = (gint32*)sci_malloc(sizeof(gint32) * device->buf_size);
P->played_this_second = 0;
P->paused = 0;
#ifdef DEBUG
sciprintf("[soft-mixer] Initialised device %s v%s (%d Hz, %d/%x)\n",
device->name, device->version,
device->conf.rate, device->conf.stereo, device->conf.format);
#endif
return SFX_OK;
}
static inline unsigned int
gcd(unsigned int a, unsigned int b) {
if (a == b)
return a;
if (a < b) {
unsigned int c = b % a;
if (!c)
return a;
return gcd(c, a);
} else
return gcd(b, a);
}
static sfx_pcm_urat_t
urat(unsigned int nom, unsigned int denom) {
sfx_pcm_urat_t rv;
unsigned int g;
rv.val = nom / denom;
nom -= rv.val * denom;
if (nom == 0)
g = 1;
else
g = gcd(nom, denom);
rv.nom = nom / g;
rv.den = denom / g;
return rv;
}
static void
mix_subscribe(sfx_pcm_mixer_t *self, sfx_pcm_feed_t *feed) {
sfx_pcm_feed_state_t *fs;
ACQUIRE_LOCK();
if (!self->feeds) {
self->feeds_allocd = 2;
self->feeds = (sfx_pcm_feed_state_t*)sci_malloc(sizeof(sfx_pcm_feed_state_t)
* self->feeds_allocd);
} else if (self->feeds_allocd == self->feeds_nr) {
self->feeds_allocd += 2;
self->feeds = (sfx_pcm_feed_state_t*)sci_realloc(self->feeds,
sizeof(sfx_pcm_feed_state_t)
* self->feeds_allocd);
}
fs = self->feeds + self->feeds_nr++;
fs->feed = feed;
feed->frame_size = SFX_PCM_FRAME_SIZE(feed->conf);
/* fs->buf_size = (self->dev->buf_size
* (feed->conf.rate
+ self->dev->conf.rate - 1))
/ self->dev->conf.rate;
*/
/* For the sake of people without 64 bit CPUs: */
fs->buf_size = 2 + /* Additional safety */
(self->dev->buf_size *
(1 + (feed->conf.rate / self->dev->conf.rate)));
warning(" ---> %d/%d/%d/%d = %d",
self->dev->buf_size,
feed->conf.rate,
self->dev->conf.rate,
feed->frame_size,
fs->buf_size);
fs->buf = (byte*)sci_malloc(fs->buf_size * feed->frame_size);
warning(" ---> --> %d for %p at %p", fs->buf_size * feed->frame_size, (void *)fs, (void *)fs->buf);
{
int i;
for (i = 0; i < fs->buf_size * feed->frame_size; i++)
fs->buf[i] = 0xa5;
}
fs->scount = urat(0, 1);
fs->spd = urat(feed->conf.rate, self->dev->conf.rate);
fs->scount.den = fs->spd.den;
fs->ch_old.left = 0;
fs->ch_old.right = 0;
fs->ch_new.left = 0;
fs->ch_new.right = 0;
fs->mode = SFX_PCM_FEED_MODE_ALIVE;
/* If the feed can't provide us with timestamps, we don't need to wait for it to do so */
fs->pending_review = (feed->get_timestamp) ? 1 : 0;
fs->frame_bufstart = 0;
#ifdef DEBUG
sciprintf("[soft-mixer] Subscribed %s-%x (%d Hz, %d/%x) at %d+%d/%d, buffer size %d\n",
feed->debug_name, feed->debug_nr, feed->conf.rate, feed->conf.stereo, feed->conf.format,
fs->spd.val, fs->spd.nom, fs->spd.den, fs->buf_size);
#endif
RELEASE_LOCK();
}
static void
_mix_unsubscribe(sfx_pcm_mixer_t *self, sfx_pcm_feed_t *feed) {
int i;
#ifdef DEBUG
sciprintf("[soft-mixer] Unsubscribing %s-%x\n", feed->debug_name, feed->debug_nr);
#endif
for (i = 0; i < self->feeds_nr; i++) {
sfx_pcm_feed_state_t *fs = self->feeds + i;
if (fs->feed == feed) {
feed->destroy(feed);
if (fs->buf)
free(fs->buf);
self->feeds_nr--;
/* Copy topmost into deleted so that we don't have any holes */
if (i != self->feeds_nr)
self->feeds[i] = self->feeds[self->feeds_nr];
if (self->feeds_allocd > 8 && self->feeds_allocd > (self->feeds_nr << 1)) {
/* Limit memory waste */
self->feeds_allocd >>= 1;
self->feeds
= (sfx_pcm_feed_state_t*)sci_realloc(self->feeds,
sizeof(sfx_pcm_feed_state_t)
* self->feeds_allocd);
}
for (i = 0; i < self->feeds_nr; i++)
warning(" Feed #%d: %s-%x",
i, self->feeds[i].feed->debug_name,
self->feeds[i].feed->debug_nr);
return;
}
}
error("[sfx-mixer] Assertion failed: Deleting invalid feed %p out of %d",
(void *)feed, self->feeds_nr);
BREAKPOINT();
}
static void
mix_exit(sfx_pcm_mixer_t *self) {
ACQUIRE_LOCK();
while (self->feeds_nr)
_mix_unsubscribe(self, self->feeds[0].feed);
if (P->outbuf)
free(P->outbuf);
if (P->writebuf)
free(P->writebuf);
if (P->compbuf_l)
free(P->compbuf_l);
if (P->compbuf_l)
free(P->compbuf_r);
free(P);
self->private_bits /* = P */ = NULL;
RELEASE_LOCK();
#ifdef DEBUG
sciprintf("[soft-mixer] Uninitialising mixer\n");
#endif
}
#define LIMIT_16_BITS(v) \
if (v < -32767) \
v = -32768; \
else if (v > 32766) \
v = 32767
static inline void
mix_compute_output(sfx_pcm_mixer_t *self, int outplen) {
int frame_i;
sfx_pcm_config_t conf = self->dev->conf;
int use_16 = conf.format & SFX_PCM_FORMAT_16;
int bias = conf.format & ~SFX_PCM_FORMAT_LMASK;
byte *lchan, *rchan = NULL;
/* Don't see how this could possibly wind up being
** used w/o initialisation, but you never know... */
gint32 *lsrc = P->compbuf_l;
gint32 *rsrc = P->compbuf_r;
int frame_size = SFX_PCM_FRAME_SIZE(conf);
if (!P->writebuf)
P->writebuf = (byte*)sci_malloc(self->dev->buf_size * frame_size + 4);
if (conf.stereo) {
if (conf.stereo == SFX_PCM_STEREO_RL) {
lchan = P->writebuf + ((use_16) ? 2 : 1);
rchan = P->writebuf;
} else {
lchan = P->writebuf;
rchan = P->writebuf + ((use_16) ? 2 : 1);
}
} else
lchan = P->writebuf;
for (frame_i = 0; frame_i < outplen; frame_i++) {
int left = *lsrc++;
int right = *rsrc++;
if (conf.stereo) {
LIMIT_16_BITS(left);
LIMIT_16_BITS(right);
if (!use_16) {
left >>= 8;
right >>= 8;
}
left += bias;
right += bias;
if (use_16) {
if (SFX_PCM_FORMAT_LE == (conf.format & SFX_PCM_FORMAT_ENDIANNESS)) {
lchan[0] = left & 0xff;
lchan[1] = (left >> 8) & 0xff;
rchan[0] = right & 0xff;
rchan[1] = (right >> 8) & 0xff;
} else {
lchan[1] = left & 0xff;
lchan[0] = (left >> 8) & 0xff;
rchan[1] = right & 0xff;
rchan[0] = (right >> 8) & 0xff;
}
lchan += 4;
rchan += 4;
} else {
*lchan = left & 0xff;
*rchan = right & 0xff;
lchan += 2;
rchan += 2;
}
} else {
left += right;
left >>= 1;
LIMIT_16_BITS(left);
if (!use_16)
left >>= 8;
left += bias;
if (use_16) {
if (SFX_PCM_FORMAT_LE == (conf.format & SFX_PCM_FORMAT_ENDIANNESS)) {
lchan[0] = left & 0xff;
lchan[1] = (left >> 8) & 0xff;
} else {
lchan[1] = left & 0xff;
lchan[0] = (left >> 8) & 0xff;
}
lchan += 2;
} else {
*lchan = left & 0xff;
lchan += 1;
}
}
}
}
static inline void
mix_swap_buffers(sfx_pcm_mixer_t *self) { /* Swap buffers */
byte *tmp = P->outbuf;
P->outbuf = P->writebuf;
P->writebuf = tmp;
}
#define FRAME_OFFSET(usecs) \
((usecs >> 7) /* approximate, since uint32 is too small */ \
* ((long) self->dev->conf.rate)) \
/ (1000000L >> 7)
static inline int
mix_compute_buf_len(sfx_pcm_mixer_t *self, int *skip_frames)
/* Computes the number of frames we ought to write. It tries to minimise the number,
** in order to reduce latency. */
/* It sets 'skip_frames' to the number of frames to assume lost by latency, effectively
** skipping them. */
{
int free_frames;
int played_frames = 0; /* since the last call */
long secs, usecs;
int frame_pos;
int result_frames;
sci_gettime(&secs, &usecs);
if (!P->outbuf) {
/* Called for the first time ever? */
P->skew = usecs;
P->lsec = secs;
P->max_delta = 0;
P->delta_observations = 0;
P->played_this_second = 0;
*skip_frames = 0;
return self->dev->buf_size;
}
/* error("[%d:%d]S%d ", secs, usecs, P->skew);*/
if (P->skew > usecs) {
secs--;
usecs += (1000000 - P->skew);
} else
usecs -= P->skew;
frame_pos = FRAME_OFFSET(usecs);
played_frames = frame_pos - P->played_this_second
+ ((secs - P->lsec) * self->dev->conf.rate);
/*
error("%d:%d - %d:%d => %d", secs, frame_pos,
P->lsec, P->played_this_second, played_frames);
*/
if (played_frames > self->dev->buf_size)
played_frames = self->dev->buf_size;
/*
error("Between %d:? offset=%d and %d:%d offset=%d: Played %d at %d", P->lsec, P->played_this_second,
secs, usecs, frame_pos, played_frames, self->dev->conf.rate);
*/
if (played_frames > P->max_delta)
P->max_delta = played_frames;
free_frames = played_frames;
if (free_frames > self->dev->buf_size) {
if (!diagnosed_too_slow) {
sciprintf("[sfx-mixer] Your timer is too slow for your PCM output device (%d/%d), free=%d.\n"
"[sfx-mixer] You might want to try changing the device, timer, or mixer, if possible.\n",
played_frames, self->dev->buf_size, free_frames);
}
diagnosed_too_slow = 1;
*skip_frames = free_frames - self->dev->buf_size;
free_frames = self->dev->buf_size;
} else
*skip_frames = 0;
++P->delta_observations;
if (P->delta_observations > MAX_DELTA_OBSERVATIONS)
P->delta_observations = MAX_DELTA_OBSERVATIONS;
/* /\* Disabled, broken *\/ */
/* if (0 && P->delta_observations > MIN_DELTA_OBSERVATIONS) { /\* Start improving after a while *\/ */
/* int diff = self->dev->conf.rate - P->max_delta; */
/* /\* log-approximate P->max_delta over time *\/ */
/* recommended_frames = P->max_delta + */
/* ((diff * MIN_DELTA_OBSERVATIONS) / P->delta_observations); */
/* /\* WTF? *\/ */
/* } else */
/* recommended_frames = self->dev->buf_size; /\* Initially, keep the buffer full *\/ */
#if (DEBUG >= 1)
sciprintf("[soft-mixer] played since last time: %d, recommended: %d, free: %d\n",
played_frames, recommended_frames, free_frames);
#endif
result_frames = free_frames;
if (result_frames < 0)
result_frames = 0;
P->played_this_second += result_frames;
while (P->played_this_second >= self->dev->conf.rate) {
/* Won't normally happen more than once */
P->played_this_second -= self->dev->conf.rate;
P->lsec++;
}
if (result_frames > self->dev->buf_size) {
error("[soft-mixer] Internal assertion failed: frames-to-write %d > %d",
result_frames, self->dev->buf_size);
}
return result_frames;
}
#define READ_NEW_VALUES() \
if (frames_left > 0) { \
if (bias) { /* unsigned data */ \
if (!use_16) { \
c_new.left = (*lsrc) << 8; \
c_new.right = (*rsrc) << 8; \
} else { \
if (conf.format & SFX_PCM_FORMAT_LE) { \
c_new.left = lsrc[0] | lsrc[1] << 8; \
c_new.right = rsrc[0] | rsrc[1] << 8; \
} else { \
c_new.left = lsrc[1] | lsrc[0] << 8; \
c_new.right = rsrc[1] | rsrc[0] << 8; \
} \
} \
} else { /* signed data */ \
if (!use_16) { \
c_new.left = (*((signed char *)lsrc)) << 8; \
c_new.right = (*((signed char *)rsrc)) << 8; \
} else { \
if (conf.format & SFX_PCM_FORMAT_LE) { \
c_new.left = lsrc[0] | ((signed char *)lsrc)[1] << 8; \
c_new.right = rsrc[0] | ((signed char *)rsrc)[1] << 8; \
} else { \
c_new.left = lsrc[1] | ((signed char *)lsrc)[0] << 8; \
c_new.right = rsrc[1] | ((signed char *)rsrc)[0] << 8; \
} \
} \
} \
\
c_new.left -= bias; \
c_new.right -= bias; \
\
lsrc += frame_size; \
rsrc += frame_size; \
} else { \
c_new.left = c_new.right = 0; \
break; \
}
static volatile int xx_offset;
static volatile int xx_size;
static void
mix_compute_input_linear(sfx_pcm_mixer_t *self, int add_result,
int len, sfx_timestamp_t *ts, sfx_timestamp_t base_ts)
/* if add_result is non-zero, P->outbuf should be added to rather than overwritten. */
/* base_ts is the timestamp for the first frame */
{
sfx_pcm_feed_state_t *fs = self->feeds + add_result;
sfx_pcm_feed_t *f = fs->feed;
sfx_pcm_config_t conf = f->conf;
int use_16 = conf.format & SFX_PCM_FORMAT_16;
gint32 *lchan = P->compbuf_l;
gint32 *rchan = P->compbuf_r;
int frame_size = f->frame_size;
byte *wr_dest = fs->buf + (frame_size * fs->frame_bufstart);
byte *lsrc = fs->buf;
byte *rsrc = fs->buf;
/* Location to write to */
int frames_nr;
int bias = (conf.format & ~SFX_PCM_FORMAT_LMASK) ? 0x8000 : 0;
/* We use this only on a 16 bit level here */
/* The two most extreme source frames we consider for a
** destination frame */
struct twochannel_data c_old = fs->ch_old;
struct twochannel_data c_new = fs->ch_new;
int frames_read = 0;
int frames_left;
int write_offset; /* Iterator for translation */
int delay_frames = 0; /* Number of frames (dest buffer) at the beginning we skip */
/* First, compute the number of frames we want to retrieve */
frames_nr = fs->spd.val * len;
/* A little complicated since we must consider partial frames */
frames_nr += (fs->spd.nom * len
+ (fs->scount.den - fs->scount.nom) /* remember that we may have leftovers */
+ (fs->spd.den - 1 /* round up */)
)
/ fs->spd.den;
ts->secs = -1;
if (frames_nr > fs->buf_size) {
error("%d (%d*%d + somethign) bytes, but only %d allowed!!!!",
frames_nr * f->frame_size,
fs->spd.val, len,
fs->buf_size);
BREAKPOINT();
}
if (fs->pending_review) {
int newmode = PCM_FEED_EMPTY; /* empty unless a get_timestamp() tells otherwise */
RELEASE_LOCK();
/* Retrieve timestamp */
if (f->get_timestamp)
newmode = f->get_timestamp(f, ts);
ACQUIRE_LOCK();
fs = self->feeds + add_result;
/* Reset in case of status update */
switch (newmode) {
case PCM_FEED_TIMESTAMP: {
/* Compute the number of frames the returned timestamp is in the future: */
delay_frames =
sfx_timestamp_frame_diff(sfx_timestamp_renormalise(*ts, base_ts.frame_rate),
base_ts);
if (delay_frames <= 0)
/* Start ASAP, even if it's too late */
delay_frames = 0;
else
if (delay_frames > len)
delay_frames = len;
fs->pending_review = 0;
}
break;
case PCM_FEED_EMPTY:
fs->mode = SFX_PCM_FEED_MODE_DEAD;
/* ...fall through... */
case PCM_FEED_IDLE:
/* Clear audio buffer, if neccessary, and return */
if (!add_result) {
memset(P->compbuf_l, 0, sizeof(gint32) * len);
memset(P->compbuf_r, 0, sizeof(gint32) * len);
}
return;
default:
error("[soft-mixer] Fatal: Invalid mode returned by PCM feed %s-%d's get_timestamp(): %d",
f->debug_name, f->debug_nr, newmode);
exit(1);
}
}
RELEASE_LOCK();
/* Make sure we have sufficient information */
if (frames_nr > delay_frames + fs->frame_bufstart)
frames_read =
f->poll(f, wr_dest,
frames_nr
- delay_frames
- fs->frame_bufstart);
ACQUIRE_LOCK();
fs = self->feeds + add_result;
frames_read += fs->frame_bufstart;
frames_left = frames_read;
/* Reset in case of status update */
/* Skip at the beginning: */
if (delay_frames) {
if (!add_result) {
memset(lchan, 0, sizeof(gint32) * delay_frames);
memset(rchan, 0, sizeof(gint32) * delay_frames);
}
lchan += delay_frames;
rchan += delay_frames;
len -= delay_frames;
}
#if (DEBUG >= 2)
sciprintf("[soft-mixer] Examining %s-%x (frame size %d); read %d/%d/%d, re-using %d frames\n",
f->debug_name, f->debug_nr, frame_size, frames_read, frames_nr,
fs->buf_size, fs->frame_bufstart);
#endif
if (conf.stereo == SFX_PCM_STEREO_LR)
rsrc += (use_16) ? 2 : 1;
else if (conf.stereo == SFX_PCM_STEREO_RL)
lsrc += (use_16) ? 2 : 1;
/* Otherwise, we let both point to the same place */
#if (DEBUG >= 2)
sciprintf("[soft-mixer] Stretching theoretical %d (physical %d) results to %d\n", frames_nr, frames_left, len);
#endif
for (write_offset = 0; write_offset < len; write_offset++) {
int leftsum = 0; /* Sum of any complete frames we used */
int rightsum = 0;
int left; /* Sum of the two most extreme source frames
** we considered, i.e. the oldest and newest
** one corresponding to the output frame we are
** computing */
int right;
int frame_steps = fs->spd.val;
int j;
if (fs->scount.nom >= fs->scount.den) {
fs->scount.nom -= fs->scount.den; /* Ensure fractional part < 1 */
++frame_steps;
}
if (frame_steps)
c_old = c_new;
#if 0
if (write_offset == 0) {
READ_NEW_VALUES();
--frames_left;
#if (DEBUG >= 3)
sciprintf("[soft-mixer] Initial read %d:%d\n", c_new.left, c_new.right);
#endif
c_old = c_new;
}
#endif
for (j = 0; j < frame_steps; j++) {
READ_NEW_VALUES();
--frames_left;
#if (DEBUG >= 3)
sciprintf("[soft-mixer] Step %d/%d made %d:%d\n", j, frame_steps, c_new.left, c_new.right);
#endif
/* The last frame will be subject to the fractional
** part analysis, so we add it to 'left' and 'right'
** later-- all others are added to (leftsum, rightsum).
*/
if (j + 1 < frame_steps) {
leftsum += c_new.left;
rightsum += c_new.right;
}
}
left = c_new.left * fs->scount.nom
+ c_old.left * (fs->scount.den - fs->scount.nom);
right = c_new.right * fs->scount.nom
+ c_old.right * (fs->scount.den - fs->scount.nom);
/* Normalise */
left /= fs->spd.den;
right /= fs->spd.den;
leftsum += left;
rightsum += right;
/* Make sure to divide by the number of frames we added here */
if (frame_steps > 1) {
leftsum /= (frame_steps);
rightsum /= (frame_steps);
}
#if (DEBUG >= 3)
sciprintf("[soft-mixer] Ultimate result: %d:%d (frac %d:%d)\n", leftsum, rightsum, left, right);
#endif
if (add_result) {
*(lchan++) += leftsum;
*(rchan++) += rightsum;
} else {
*(lchan++) = leftsum;
*(rchan++) = rightsum;
}
fs->scount.nom += fs->spd.nom; /* Count up fractional part */
}
fs->ch_old = c_old;
fs->ch_new = c_new;
/* If neccessary, zero out the rest */
if (write_offset < len && !add_result) {
memset(lchan, 0, sizeof(gint32) * (len - write_offset));
memset(rchan, 0, sizeof(gint32) * (len - write_offset));
}
/* Save whether we have a partial frame still stored */
fs->frame_bufstart = frames_left;
if (frames_left) {
xx_offset = ((frames_read - frames_left) * f->frame_size);
xx_size = frames_left * f->frame_size;
if (xx_offset + xx_size
>= fs->buf_size * f->frame_size) {
error("offset %d >= max %d",
(xx_offset + xx_size), fs->buf_size * f->frame_size);
BREAKPOINT();
}
memmove(fs->buf,
fs->buf + ((frames_read - frames_left) * f->frame_size),
frames_left * f->frame_size);
}
#if (DEBUG >= 2)
sciprintf("[soft-mixer] Leaving %d over\n", fs->frame_bufstart);
#endif
if (frames_read + delay_frames < frames_nr) {
if (f->get_timestamp) /* Can resume? */
fs->pending_review = 1;
else
fs->mode = SFX_PCM_FEED_MODE_DEAD; /* Done. */
}
}
static int
mix_process_linear(sfx_pcm_mixer_t *self) {
ACQUIRE_LOCK();
{
int src_i; /* source feed index counter */
int frames_skip; /* Number of frames to discard, rather than to emit */
int buflen = mix_compute_buf_len(self, &frames_skip); /* Compute # of frames we must compute and write */
int fake_buflen;
int timestamp_max_delta = 0;
int have_timestamp = 0;
sfx_timestamp_t start_timestamp; /* The timestamp at which the first frame will be played */
sfx_timestamp_t min_timestamp;
min_timestamp.secs = 0;
sfx_timestamp_t timestamp;
if (self->dev->get_output_timestamp)
start_timestamp = self->dev->get_output_timestamp(self->dev);
else {
long sec, usec;
sci_gettime(&sec, &usec);
start_timestamp = sfx_new_timestamp(sec, usec, self->dev->conf.rate);
}
if ((P->outbuf) && (P->lastbuf_len)) {
sfx_timestamp_t ts;
int rv;
if (P->have_outbuf_timestamp) {
ts = sfx_timestamp_renormalise(P->outbuf_timestamp, self->dev->conf.rate);
}
rv = self->dev->output(self->dev, P->outbuf,
P->lastbuf_len,
(P->have_outbuf_timestamp) ? &ts : NULL);
if (rv == SFX_ERROR) {
RELEASE_LOCK();
return rv; /* error */
}
}
#if (DEBUG >= 1)
if (self->feeds_nr)
sciprintf("[soft-mixer] Mixing %d output frames on %d input feeds\n", buflen, self->feeds_nr);
#endif
if (self->feeds_nr && !P->paused) {
/* Below, we read out all feeds in case we have to skip frames first, then get the
** most current sound. 'fake_buflen' is either the actual buflen (for the last iteration)
** or a fraction of the buf length to discard. */
do {
if (frames_skip) {
if (frames_skip > self->dev->buf_size)
fake_buflen = self->dev->buf_size;
else
fake_buflen = frames_skip;
frames_skip -= fake_buflen;
} else {
fake_buflen = buflen;
frames_skip = -1; /* Mark us as being completely done */
}
for (src_i = 0; src_i < self->feeds_nr; src_i++) {
mix_compute_input_linear(self, src_i,
fake_buflen, ×tamp,
start_timestamp);
if (timestamp.secs >= 0) {
if (have_timestamp) {
int diff = sfx_timestamp_usecs_diff(min_timestamp, timestamp);
if (diff > 0) {
/* New earlier timestamp */
timestamp = min_timestamp;
timestamp_max_delta += diff;
} else if (diff > timestamp_max_delta)
timestamp_max_delta = diff;
/* New max delta for timestamp */
} else {
min_timestamp = timestamp;
have_timestamp = 1;
}
}
}
/* Destroy all feeds we finished */
for (src_i = 0; src_i < self->feeds_nr; src_i++)
if (self->feeds[src_i].mode == SFX_PCM_FEED_MODE_DEAD)
_mix_unsubscribe(self, self->feeds[src_i].feed);
} while (frames_skip >= 0);
} else { /* Zero it out */
memset(P->compbuf_l, 0, sizeof(gint32) * buflen);
memset(P->compbuf_r, 0, sizeof(gint32) * buflen);
}
#if (DEBUG >= 1)
if (self->feeds_nr)
sciprintf("[soft-mixer] Done mixing for this session, the result will be our next output buffer\n");
#endif
#if (DEBUG >= 3)
if (self->feeds_nr) {
int i;
sciprintf("[soft-mixer] Intermediate representation:\n");
for (i = 0; i < buflen; i++)
sciprintf("[soft-mixer] Offset %d:\t[%04x:%04x]\t%d:%d\n", i,
P->compbuf_l[i] & 0xffff, P->compbuf_r[i] & 0xffff,
P->compbuf_l[i], P->compbuf_r[i]);
}
#endif
if (timestamp_max_delta > TIMESTAMP_MAX_ALLOWED_DELTA)
sciprintf("[soft-mixer] Warning: Difference in timestamps between audio feeds is %d us\n", timestamp_max_delta);
mix_compute_output(self, buflen);
P->lastbuf_len = buflen;
/* Finalize */
mix_swap_buffers(self);
if (have_timestamp)
P->outbuf_timestamp = sfx_timestamp_add(min_timestamp,
timestamp_max_delta >> 1);
P->have_outbuf_timestamp = have_timestamp;
}
RELEASE_LOCK();
return SFX_OK;
}
static void
mix_pause(sfx_pcm_mixer_t *self) {
ACQUIRE_LOCK();
P->paused = 1;
RELEASE_LOCK();
}
static void
mix_resume(sfx_pcm_mixer_t *self) {
ACQUIRE_LOCK();
P->paused = 0;
RELEASE_LOCK();
}
sfx_pcm_mixer_t sfx_pcm_mixer_soft_linear = {
"soft-linear",
"0.1",
mix_init,
mix_exit,
mix_subscribe,
mix_pause,
mix_resume,
mix_process_linear,
0,
0,
NULL,
NULL,
NULL
};
sfx_pcm_mixer_t* getMixer() { return &sfx_pcm_mixer_soft_linear; }
} // End of namespace Sci
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