blob: 2e8bc3f47c496aa9bda994f3a30f415ad52dd0ed [file] [log] [blame]
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 by Miika Pekkarinen
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdio.h>
#include "config.h"
#include "system.h"
#include "debug.h"
#include <kernel.h>
#include "pcm.h"
#include "pcm_mixer.h"
#include "pcmbuf.h"
#include "playback.h"
#include "codec_thread.h"
/* Define LOGF_ENABLE to enable logf output in this file */
/*#define LOGF_ENABLE*/
#include "logf.h"
#if (CONFIG_PLATFORM & PLATFORM_NATIVE)
#include "cpu.h"
#endif
#include <string.h>
#include "settings.h"
#include "audio.h"
#include "voice_thread.h"
#include "dsp.h"
#define PCMBUF_TARGET_CHUNK 32768 /* This is the target fill size of chunks
on the pcm buffer */
#define PCMBUF_MINAVG_CHUNK 24576 /* This is the minimum average size of
chunks on the pcm buffer (or we run out
of buffer descriptors, which is
non-fatal) */
#define PCMBUF_MIN_CHUNK 4096 /* We try to never feed a chunk smaller than
this to the DMA */
#define CROSSFADE_BUFSIZE 8192 /* Size of the crossfade buffer */
/* number of bytes played per second (sample rate * 2 channels * 2 bytes/sample) */
#define BYTERATE (NATIVE_FREQUENCY * 4)
#if MEMORYSIZE > 2
/* Keep watermark high for iPods at least (2s) */
#define PCMBUF_WATERMARK (BYTERATE * 2)
#else
#define PCMBUF_WATERMARK (BYTERATE / 4) /* 0.25 seconds */
#endif
/* Structure we can use to queue pcm chunks in memory to be played
* by the driver code. */
struct chunkdesc
{
unsigned char *addr;
size_t size;
struct chunkdesc* link;
/* true if last chunk in the track */
bool end_of_track;
};
#define NUM_CHUNK_DESCS(bufsize) \
((bufsize) / PCMBUF_MINAVG_CHUNK)
/* Size of the PCM buffer. */
static size_t pcmbuf_size = 0;
static char *pcmbuf_bufend;
static char *pcmbuffer;
/* Current PCM buffer write index. */
static size_t pcmbuffer_pos;
/* Amount pcmbuffer_pos will be increased.*/
static size_t pcmbuffer_fillpos;
static struct chunkdesc *first_desc;
/* Gapless playback */
static bool track_transition;
/* Fade effect */
static unsigned int fade_vol = MIX_AMP_UNITY;
/* Voice */
static bool soft_mode = false;
#ifdef HAVE_CROSSFADE
/* Crossfade buffer */
static char *fadebuf;
/* Crossfade related state */
static bool crossfade_enabled;
static bool crossfade_enable_request;
static bool crossfade_mixmode;
static bool crossfade_auto_skip;
static bool crossfade_active;
static bool crossfade_track_change_started;
/* Track the current location for processing crossfade */
static struct chunkdesc *crossfade_chunk;
static size_t crossfade_sample;
/* Counters for fading in new data */
static size_t crossfade_fade_in_total;
static size_t crossfade_fade_in_rem;
#endif
static struct chunkdesc *read_chunk;
static struct chunkdesc *read_end_chunk;
static struct chunkdesc *write_chunk;
static struct chunkdesc *write_end_chunk;
static size_t last_chunksize;
static size_t pcmbuf_unplayed_bytes;
static size_t pcmbuf_watermark;
static bool low_latency_mode = false;
static bool flush_pcmbuf = false;
#ifdef HAVE_PRIORITY_SCHEDULING
static int codec_thread_priority = PRIORITY_PLAYBACK;
#endif
/* Helpful macros for use in conditionals this assumes some of the above
* static variable names */
#define COMMIT_IF_NEEDED if(pcmbuffer_fillpos > PCMBUF_TARGET_CHUNK || \
(pcmbuffer_pos + pcmbuffer_fillpos) >= pcmbuf_size) commit_chunk(false)
#define LOW_DATA(quarter_secs) \
(pcmbuf_unplayed_bytes < NATIVE_FREQUENCY * quarter_secs)
#ifdef HAVE_CROSSFADE
static void crossfade_start(void);
static void write_to_crossfade(size_t length);
static void pcmbuf_finish_crossfade_enable(void);
#endif
/* Callbacks into playback.c */
extern void audio_pcmbuf_position_callback(unsigned int time);
extern void audio_pcmbuf_track_change(bool pcmbuf);
extern bool audio_pcmbuf_may_play(void);
/**************************************/
/* define this to show detailed chunkdesc usage information on the sim console */
/*#define DESC_DEBUG*/
#ifndef SIMULATOR
#undef DESC_DEBUG
#endif
#ifdef DESC_DEBUG
#define DISPLAY_DESC(caller) while(!show_desc(caller))
#define DESC_IDX(desc) (desc ? desc - first_desc : -1)
#define SHOW_DESC(desc) if(DESC_IDX(desc)==-1) DEBUGF("--"); \
else DEBUGF("%02d", DESC_IDX(desc))
#define SHOW_DESC_LINK(desc) if(desc){SHOW_DESC(desc->link);DEBUGF(" ");} \
else DEBUGF("-- ")
#define SHOW_DETAIL(desc) DEBUGF(":");SHOW_DESC(desc); DEBUGF(">"); \
SHOW_DESC_LINK(desc)
#define SHOW_POINT(tag,desc) DEBUGF("%s",tag);SHOW_DETAIL(desc)
#define SHOW_NUM(num,desc) DEBUGF("%02d>",num);SHOW_DESC_LINK(desc)
static bool show_desc(char *caller)
{
if (show_desc_in_use) return false;
show_desc_in_use = true;
DEBUGF("%-14s\t", caller);
SHOW_POINT("r", read_chunk);
SHOW_POINT("re", read_end_chunk);
DEBUGF(" ");
SHOW_POINT("w", write_chunk);
SHOW_POINT("we", write_end_chunk);
DEBUGF("\n");
int i;
for (i = 0; i < pcmbuf_descs(); i++)
{
SHOW_NUM(i, (first_desc + i));
if (i%10 == 9) DEBUGF("\n");
}
DEBUGF("\n\n");
show_desc_in_use = false;
return true;
}
#else
#define DISPLAY_DESC(caller) do{}while(0)
#endif
/** Accept new PCM data */
/* Commit PCM buffer samples as a new chunk for playback */
static void commit_chunk(bool flush_next_time)
{
if (!pcmbuffer_fillpos)
return;
/* Never use the last buffer descriptor */
while (write_chunk == write_end_chunk) {
/* If this happens, something is being stupid */
if (!pcm_is_playing()) {
logf("commit_chunk error");
pcmbuf_play_start();
}
/* Let approximately one chunk of data playback */
sleep(HZ * PCMBUF_TARGET_CHUNK / BYTERATE);
}
/* commit the chunk */
register size_t size = pcmbuffer_fillpos;
/* Grab the next description to write, and change the write pointer */
register struct chunkdesc *pcmbuf_current = write_chunk;
write_chunk = pcmbuf_current->link;
/* Fill in the values in the new buffer chunk */
pcmbuf_current->addr = &pcmbuffer[pcmbuffer_pos];
pcmbuf_current->size = size;
pcmbuf_current->end_of_track = false;
pcmbuf_current->link = NULL;
if (read_chunk != NULL)
{
if (flush_pcmbuf)
{
/* Flush! Discard all data after the currently playing chunk,
and make the current chunk play next */
logf("commit_chunk: flush");
pcm_play_lock();
write_end_chunk->link = read_chunk->link;
read_chunk->link = pcmbuf_current;
while (write_end_chunk->link)
{
write_end_chunk = write_end_chunk->link;
pcmbuf_unplayed_bytes -= write_end_chunk->size;
}
read_chunk->end_of_track = track_transition;
pcm_play_unlock();
}
/* If there is already a read buffer setup, add to it */
else
read_end_chunk->link = pcmbuf_current;
}
else
{
/* Otherwise create the buffer */
read_chunk = pcmbuf_current;
}
/* If flush_next_time is true, then the current chunk will be thrown out
* and the next chunk to be committed will be the next to be played.
* This is used to empty the PCM buffer for a track change. */
flush_pcmbuf = flush_next_time;
/* This is now the last buffer to read */
read_end_chunk = pcmbuf_current;
/* Update bytes counters */
pcmbuf_unplayed_bytes += size;
pcmbuffer_pos += size;
if (pcmbuffer_pos >= pcmbuf_size)
pcmbuffer_pos -= pcmbuf_size;
pcmbuffer_fillpos = 0;
DISPLAY_DESC("commit_chunk");
}
/* Set priority of the codec thread */
#ifdef HAVE_PRIORITY_SCHEDULING
/*
* expects pcm_fill_state in tenth-% units (e.g. full pcm buffer is 10) */
static void boost_codec_thread(int pcm_fill_state)
{
static const int prios[11] = {
PRIORITY_PLAYBACK_MAX, /* 0 - 10% */
PRIORITY_PLAYBACK_MAX+1, /* 10 - 20% */
PRIORITY_PLAYBACK_MAX+3, /* 20 - 30% */
PRIORITY_PLAYBACK_MAX+5, /* 30 - 40% */
PRIORITY_PLAYBACK_MAX+7, /* 40 - 50% */
PRIORITY_PLAYBACK_MAX+8, /* 50 - 60% */
PRIORITY_PLAYBACK_MAX+9, /* 60 - 70% */
/* raiseing priority above 70% shouldn't be needed */
PRIORITY_PLAYBACK, /* 70 - 80% */
PRIORITY_PLAYBACK, /* 80 - 90% */
PRIORITY_PLAYBACK, /* 90 -100% */
PRIORITY_PLAYBACK, /* 100% */
};
int new_prio = prios[pcm_fill_state];
/* Keep voice and codec threads at the same priority or else voice
* will starve if the codec thread's priority is boosted. */
if (new_prio != codec_thread_priority)
{
codec_thread_set_priority(new_prio);
voice_thread_set_priority(new_prio);
codec_thread_priority = new_prio;
}
}
#else
#define boost_codec_thread(pcm_fill_state) do{}while(0)
#endif /* HAVE_PRIORITY_SCHEDULING */
/* Return true if the PCM buffer is able to receive new data.
* Also maintain buffer level above the watermark. */
static bool prepare_insert(size_t length)
{
bool playing = mixer_channel_status(PCM_MIXER_CHAN_PLAYBACK) != CHANNEL_STOPPED;
if (low_latency_mode)
{
/* 1/4s latency. */
if (!LOW_DATA(1) && playing)
return false;
}
/* Need to save PCMBUF_MIN_CHUNK to prevent wrapping overwriting */
if (pcmbuf_free() < length + PCMBUF_MIN_CHUNK)
return false;
/* Maintain the buffer level above the watermark */
if (playing)
{
/* boost cpu if necessary */
if (pcmbuf_unplayed_bytes < pcmbuf_watermark)
trigger_cpu_boost();
boost_codec_thread(pcmbuf_unplayed_bytes*10/pcmbuf_size);
#ifdef HAVE_CROSSFADE
/* Disable crossfade if < .5s of audio */
if (LOW_DATA(2))
{
crossfade_active = false;
}
#endif
}
else /* !playing */
{
/* Boost CPU for pre-buffer */
trigger_cpu_boost();
/* If pre-buffered to the watermark, start playback */
#if MEMORYSIZE > 2
if (!LOW_DATA(4))
#else
if (pcmbuf_unplayed_bytes > pcmbuf_watermark)
#endif
{
logf("pcm starting");
if (audio_pcmbuf_may_play())
pcmbuf_play_start();
}
}
return true;
}
/* Request space in the buffer for writing output samples */
void *pcmbuf_request_buffer(int *count)
{
#ifdef HAVE_CROSSFADE
/* we're going to crossfade to a new track, which is now on its way */
if (crossfade_track_change_started)
crossfade_start();
/* crossfade has begun, put the new track samples in fadebuf */
if (crossfade_active)
{
int cnt = MIN(*count, CROSSFADE_BUFSIZE/4);
if (prepare_insert(cnt << 2))
{
*count = cnt;
return fadebuf;
}
}
else
#endif
/* if possible, reserve room in the PCM buffer for new samples */
{
if(prepare_insert(*count << 2))
{
size_t pcmbuffer_index = pcmbuffer_pos + pcmbuffer_fillpos;
if (pcmbuf_size - pcmbuffer_index >= PCMBUF_MIN_CHUNK)
{
/* Usual case, there's space here */
return &pcmbuffer[pcmbuffer_index];
}
else
{
/* Wrap the buffer, the new samples go at the beginning */
commit_chunk(false);
pcmbuffer_pos = 0;
return &pcmbuffer[0];
}
}
}
/* PCM buffer not ready to receive new data yet */
return NULL;
}
/* Handle new samples to the buffer */
void pcmbuf_write_complete(int count)
{
size_t length = (size_t)(unsigned int)count << 2;
#ifdef HAVE_CROSSFADE
if (crossfade_active)
write_to_crossfade(length);
else
#endif
{
pcmbuffer_fillpos += length;
COMMIT_IF_NEEDED;
}
}
/** Init */
static inline void init_pcmbuffers(void)
{
first_desc = write_chunk;
struct chunkdesc *next = write_chunk;
next++;
write_end_chunk = write_chunk;
while ((void *)next < (void *)pcmbuf_bufend) {
write_end_chunk->link=next;
write_end_chunk=next;
next++;
}
DISPLAY_DESC("init");
}
static size_t get_next_required_pcmbuf_size(void)
{
size_t seconds = 1;
#ifdef HAVE_CROSSFADE
if (crossfade_enable_request)
seconds += global_settings.crossfade_fade_out_delay +
global_settings.crossfade_fade_out_duration;
#endif
#if MEMORYSIZE > 2
/* Buffer has to be at least 2s long. */
seconds += 2;
#endif
logf("pcmbuf len: %ld", (long)seconds);
return seconds * BYTERATE;
}
/* Initialize the pcmbuffer the structure looks like this:
* ...|---------PCMBUF---------[|FADEBUF]|DESCS|... */
size_t pcmbuf_init(unsigned char *bufend)
{
pcmbuf_bufend = bufend;
pcmbuf_size = get_next_required_pcmbuf_size();
write_chunk = (struct chunkdesc *)pcmbuf_bufend -
NUM_CHUNK_DESCS(pcmbuf_size);
#ifdef HAVE_CROSSFADE
fadebuf = (unsigned char *)write_chunk -
(crossfade_enable_request ? CROSSFADE_BUFSIZE : 0);
pcmbuffer = fadebuf - pcmbuf_size;
#else
pcmbuffer = (unsigned char *)write_chunk - pcmbuf_size;
#endif
init_pcmbuffers();
#ifdef HAVE_CROSSFADE
pcmbuf_finish_crossfade_enable();
#else
pcmbuf_watermark = PCMBUF_WATERMARK;
#endif
pcmbuf_play_stop();
pcmbuf_soft_mode(false);
return pcmbuf_bufend - pcmbuffer;
}
/** Track change */
void pcmbuf_monitor_track_change(bool monitor)
{
pcm_play_lock();
if (last_chunksize != 0)
{
/* If monitoring, wait until this track runs out. Place in
currently playing chunk. If not, cancel notification. */
track_transition = monitor;
read_end_chunk->end_of_track = monitor;
if (!monitor)
{
/* Clear all notifications */
struct chunkdesc *desc = first_desc;
struct chunkdesc *end = desc + pcmbuf_descs();
while (desc < end)
desc++->end_of_track = false;
}
}
else
{
/* Post now if PCM stopped and last buffer was sent. */
track_transition = false;
if (monitor)
audio_pcmbuf_track_change(false);
}
pcm_play_unlock();
}
bool pcmbuf_start_track_change(bool auto_skip)
{
bool crossfade = false;
#ifdef HAVE_CROSSFADE
/* Determine whether this track change needs to crossfade */
if(crossfade_enabled && !pcmbuf_is_crossfade_active())
{
switch(global_settings.crossfade)
{
case CROSSFADE_ENABLE_AUTOSKIP:
crossfade = auto_skip;
break;
case CROSSFADE_ENABLE_MANSKIP:
crossfade = !auto_skip;
break;
case CROSSFADE_ENABLE_SHUFFLE:
crossfade = global_settings.playlist_shuffle;
break;
case CROSSFADE_ENABLE_SHUFFLE_OR_MANSKIP:
crossfade = global_settings.playlist_shuffle || !auto_skip;
break;
case CROSSFADE_ENABLE_ALWAYS:
crossfade = true;
break;
}
}
#endif
if (!auto_skip || crossfade)
/* manual skip or crossfade */
{
if (crossfade)
{ logf(" crossfade track change"); }
else
{ logf(" manual track change"); }
pcm_play_lock();
/* Cancel any pending automatic gapless transition */
pcmbuf_monitor_track_change(false);
/* Can't do two crossfades at once and, no fade if pcm is off now */
if (
#ifdef HAVE_CROSSFADE
pcmbuf_is_crossfade_active() ||
#endif
mixer_channel_status(PCM_MIXER_CHAN_PLAYBACK) == CHANNEL_STOPPED)
{
pcmbuf_play_stop();
pcm_play_unlock();
/* Notify playback that the track change starts now */
return true;
}
/* Not enough data, or not crossfading, flush the old data instead */
if (LOW_DATA(2) || !crossfade || low_latency_mode)
{
commit_chunk(true);
}
#ifdef HAVE_CROSSFADE
else
{
/* Don't enable mix mode when skipping tracks manually. */
crossfade_mixmode = auto_skip &&
global_settings.crossfade_fade_out_mixmode;
crossfade_auto_skip = auto_skip;
crossfade_track_change_started = crossfade;
}
#endif
pcm_play_unlock();
/* Keep trigger outside the play lock or HW FIFO underruns can happen
since frequency scaling is *not* always fast */
trigger_cpu_boost();
/* Notify playback that the track change starts now */
return true;
}
else /* automatic and not crossfading, so do gapless track change */
{
/* The codec is moving on to the next track, but the current track will
* continue to play. Set a flag to make sure the elapsed time of the
* current track will be updated properly, and mark the current chunk
* as the last one in the track. */
logf(" gapless track change");
pcmbuf_monitor_track_change(true);
return false;
}
}
/** Playback */
/* PCM driver callback
* This function has 3 major logical parts (separated by brackets both for
* readability and variable scoping). The first part performs the
* operations related to finishing off the last chunk we fed to the DMA.
* The second part detects the end of playlist condition when the PCM
* buffer is empty except for uncommitted samples. Then they are committed
* and sent to the PCM driver for playback. The third part performs the
* operations involved in sending a new chunk to the DMA. */
static void pcmbuf_pcm_callback(unsigned char** start, size_t* size)
{
{
struct chunkdesc *pcmbuf_current = read_chunk;
/* Take the finished chunk out of circulation */
read_chunk = pcmbuf_current->link;
/* if during a track transition, update the elapsed time in ms */
if (track_transition)
audio_pcmbuf_position_callback(last_chunksize * 1000 / BYTERATE);
/* if last chunk in the track, stop updates and notify audio thread */
if (pcmbuf_current->end_of_track)
{
track_transition = false;
audio_pcmbuf_track_change(true);
}
/* Put the finished chunk back into circulation */
write_end_chunk->link = pcmbuf_current;
write_end_chunk = pcmbuf_current;
#ifdef HAVE_CROSSFADE
/* If we've read over the crossfade chunk while it's still fading */
if (pcmbuf_current == crossfade_chunk)
crossfade_chunk = read_chunk;
#endif
}
{
/* Commit last samples at end of playlist */
if (pcmbuffer_fillpos && !read_chunk)
{
logf("pcmbuf_pcm_callback: commit last samples");
commit_chunk(false);
}
}
{
/* Send the new chunk to the DMA */
if(read_chunk)
{
last_chunksize = read_chunk->size;
pcmbuf_unplayed_bytes -= last_chunksize;
*size = last_chunksize;
*start = read_chunk->addr;
}
else
{
/* No more chunks */
logf("pcmbuf_pcm_callback: no more chunks");
last_chunksize = 0;
*size = 0;
*start = NULL;
}
}
DISPLAY_DESC("callback");
}
/* Force playback */
void pcmbuf_play_start(void)
{
if (mixer_channel_status(PCM_MIXER_CHAN_PLAYBACK) == CHANNEL_STOPPED &&
pcmbuf_unplayed_bytes && read_chunk != NULL)
{
logf("pcmbuf_play_start");
last_chunksize = read_chunk->size;
pcmbuf_unplayed_bytes -= last_chunksize;
mixer_channel_play_data(PCM_MIXER_CHAN_PLAYBACK,
pcmbuf_pcm_callback, NULL, 0);
}
}
void pcmbuf_play_stop(void)
{
logf("pcmbuf_play_stop");
mixer_channel_stop(PCM_MIXER_CHAN_PLAYBACK);
pcmbuf_unplayed_bytes = 0;
if (read_chunk) {
write_end_chunk->link = read_chunk;
write_end_chunk = read_end_chunk;
read_chunk = read_end_chunk = NULL;
}
last_chunksize = 0;
pcmbuffer_pos = 0;
pcmbuffer_fillpos = 0;
#ifdef HAVE_CROSSFADE
crossfade_track_change_started = false;
crossfade_active = false;
#endif
track_transition = false;
flush_pcmbuf = false;
DISPLAY_DESC("play_stop");
/* Can unboost the codec thread here no matter who's calling,
* pretend full pcm buffer to unboost */
boost_codec_thread(10);
}
void pcmbuf_pause(bool pause)
{
logf("pcmbuf_pause: %s", pause?"pause":"play");
if (mixer_channel_status(PCM_MIXER_CHAN_PLAYBACK) != CHANNEL_STOPPED)
mixer_channel_play_pause(PCM_MIXER_CHAN_PLAYBACK, !pause);
else if (!pause)
pcmbuf_play_start();
}
/** Crossfade */
/* Clip sample to signed 16 bit range */
static inline int32_t clip_sample_16(int32_t sample)
{
if ((int16_t)sample != sample)
sample = 0x7fff ^ (sample >> 31);
return sample;
}
#ifdef HAVE_CROSSFADE
/* Find the chunk that's (length) deep in the list. Return the position within
* the chunk, and leave the chunkdesc pointer pointing to the chunk. */
static size_t find_chunk(size_t length, struct chunkdesc **chunk)
{
while (*chunk && length >= (*chunk)->size)
{
length -= (*chunk)->size;
*chunk = (*chunk)->link;
}
return length;
}
/* Returns the number of bytes _NOT_ mixed/faded */
static size_t crossfade_mix_fade(int factor, size_t length, const char *buf,
size_t *out_sample, struct chunkdesc **out_chunk)
{
if (length == 0)
return 0;
const int16_t *input_buf = (const int16_t *)buf;
int16_t *output_buf = (int16_t *)((*out_chunk)->addr);
int16_t *chunk_end = SKIPBYTES(output_buf, (*out_chunk)->size);
output_buf = &output_buf[*out_sample];
int32_t sample;
while (length)
{
/* fade left and right channel at once to keep buffer alignment */
int i;
for (i = 0; i < 2; i++)
{
if (input_buf)
/* fade the input buffer and mix into the chunk */
{
sample = *input_buf++;
sample = ((sample * factor) >> 8) + *output_buf;
*output_buf++ = clip_sample_16(sample);
}
else
/* fade the chunk only */
{
sample = *output_buf;
*output_buf++ = (sample * factor) >> 8;
}
}
length -= 4; /* 2 samples, each 16 bit -> 4 bytes */
/* move to next chunk as needed */
if (output_buf >= chunk_end)
{
*out_chunk = (*out_chunk)->link;
if (!(*out_chunk))
return length;
output_buf = (int16_t *)((*out_chunk)->addr);
chunk_end = SKIPBYTES(output_buf, (*out_chunk)->size);
}
}
*out_sample = output_buf - (int16_t *)((*out_chunk)->addr);
return 0;
}
/* Initializes crossfader, calculates all necessary parameters and performs
* fade-out with the PCM buffer. */
static void crossfade_start(void)
{
size_t crossfade_rem;
size_t crossfade_need;
size_t fade_out_rem;
size_t fade_out_delay;
size_t fade_in_delay;
crossfade_track_change_started = false;
/* Reject crossfade if less than .5s of data */
if (LOW_DATA(2)) {
logf("crossfade rejected");
pcmbuf_play_stop();
return ;
}
logf("crossfade_start");
commit_chunk(false);
crossfade_active = true;
/* Initialize the crossfade buffer size to all of the buffered data that
* has not yet been sent to the DMA */
crossfade_rem = pcmbuf_unplayed_bytes;
crossfade_chunk = read_chunk->link;
crossfade_sample = 0;
/* Get fade out info from settings. */
fade_out_delay = global_settings.crossfade_fade_out_delay * BYTERATE;
fade_out_rem = global_settings.crossfade_fade_out_duration * BYTERATE;
crossfade_need = fade_out_delay + fade_out_rem;
if (crossfade_rem > crossfade_need)
{
if (crossfade_auto_skip)
/* Automatic track changes only modify the last part of the buffer,
* so find the right chunk and sample to start the crossfade */
{
crossfade_sample = find_chunk(crossfade_rem - crossfade_need,
&crossfade_chunk) / 2;
crossfade_rem = crossfade_need;
}
else
/* Manual skips occur immediately, but give time to process */
{
crossfade_rem -= crossfade_chunk->size;
crossfade_chunk = crossfade_chunk->link;
}
}
/* Truncate fade out duration if necessary. */
if (crossfade_rem < crossfade_need)
{
size_t crossfade_short = crossfade_need - crossfade_rem;
if (fade_out_rem >= crossfade_short)
fade_out_rem -= crossfade_short;
else
{
fade_out_delay -= crossfade_short - fade_out_rem;
fade_out_rem = 0;
}
}
crossfade_rem -= fade_out_delay + fade_out_rem;
/* Completely process the crossfade fade-out effect with current PCM buffer */
if (!crossfade_mixmode)
{
/* Fade out the specified amount of the already processed audio */
size_t total_fade_out = fade_out_rem;
size_t fade_out_sample;
struct chunkdesc *fade_out_chunk = crossfade_chunk;
/* Find the right chunk and sample to start fading out */
fade_out_delay += crossfade_sample * 2;
fade_out_sample = find_chunk(fade_out_delay, &fade_out_chunk) / 2;
while (fade_out_rem > 0)
{
/* Each 1/10 second of audio will have the same fade applied */
size_t block_rem = MIN(BYTERATE / 10, fade_out_rem);
int factor = (fade_out_rem << 8) / total_fade_out;
fade_out_rem -= block_rem;
crossfade_mix_fade(factor, block_rem, NULL,
&fade_out_sample, &fade_out_chunk);
}
/* zero out the rest of the buffer */
crossfade_mix_fade(0, crossfade_rem, NULL,
&fade_out_sample, &fade_out_chunk);
}
/* Initialize fade-in counters */
crossfade_fade_in_total = global_settings.crossfade_fade_in_duration * BYTERATE;
crossfade_fade_in_rem = crossfade_fade_in_total;
fade_in_delay = global_settings.crossfade_fade_in_delay * BYTERATE;
/* Find the right chunk and sample to start fading in */
fade_in_delay += crossfade_sample * 2;
crossfade_sample = find_chunk(fade_in_delay, &crossfade_chunk) / 2;
logf("crossfade_start done!");
}
/* Perform fade-in of new track */
static void write_to_crossfade(size_t length)
{
if (length)
{
char *buf = fadebuf;
if (crossfade_fade_in_rem)
{
size_t samples;
int16_t *input_buf;
/* Fade factor for this packet */
int factor =
((crossfade_fade_in_total - crossfade_fade_in_rem) << 8) /
crossfade_fade_in_total;
/* Bytes to fade */
size_t fade_rem = MIN(length, crossfade_fade_in_rem);
/* We _will_ fade this many bytes */
crossfade_fade_in_rem -= fade_rem;
if (crossfade_chunk)
{
/* Mix the data */
size_t fade_total = fade_rem;
fade_rem = crossfade_mix_fade(factor, fade_rem, buf,
&crossfade_sample, &crossfade_chunk);
length -= fade_total - fade_rem;
buf += fade_total - fade_rem;
if (!length)
return;
}
samples = fade_rem / 2;
input_buf = (int16_t *)buf;
/* Fade remaining samples in place */
while (samples--)
{
int32_t sample = *input_buf;
*input_buf++ = (sample * factor) >> 8;
}
}
if (crossfade_chunk)
{
/* Mix the data */
size_t mix_total = length;
/* A factor of 256 means mix only, no fading */
length = crossfade_mix_fade(256, length, buf,
&crossfade_sample, &crossfade_chunk);
buf += mix_total - length;
if (!length)
return;
}
while (length > 0)
{
COMMIT_IF_NEEDED;
size_t pcmbuffer_index = pcmbuffer_pos + pcmbuffer_fillpos;
size_t copy_n = MIN(length, pcmbuf_size - pcmbuffer_index);
memcpy(&pcmbuffer[pcmbuffer_index], buf, copy_n);
buf += copy_n;
pcmbuffer_fillpos += copy_n;
length -= copy_n;
}
}
/* if no more fading-in to do, stop the crossfade */
if (!(crossfade_fade_in_rem || crossfade_chunk))
crossfade_active = false;
}
static void pcmbuf_finish_crossfade_enable(void)
{
/* Copy the pending setting over now */
crossfade_enabled = crossfade_enable_request;
pcmbuf_watermark = (crossfade_enabled && pcmbuf_size) ?
/* If crossfading, try to keep the buffer full other than 1 second */
(pcmbuf_size - BYTERATE) :
/* Otherwise, just use the default */
PCMBUF_WATERMARK;
}
bool pcmbuf_is_crossfade_active(void)
{
return crossfade_active || crossfade_track_change_started;
}
void pcmbuf_request_crossfade_enable(bool on_off)
{
/* Next setting to be used, not applied now */
crossfade_enable_request = on_off;
}
bool pcmbuf_is_same_size(void)
{
/* if pcmbuffer is NULL, then not set up yet even once so always */
bool same_size = pcmbuffer ?
(get_next_required_pcmbuf_size() == pcmbuf_size) : true;
/* no buffer change needed, so finish crossfade setup now */
if (same_size)
pcmbuf_finish_crossfade_enable();
return same_size;
}
#endif /* HAVE_CROSSFADE */
/** Debug menu, other metrics */
/* Amount of bytes left in the buffer. */
size_t pcmbuf_free(void)
{
if (read_chunk != NULL)
{
void *read = (void *)read_chunk->addr;
void *write = &pcmbuffer[pcmbuffer_pos + pcmbuffer_fillpos];
if (read < write)
return (size_t)(read - write) + pcmbuf_size;
else
return (size_t) (read - write);
}
return pcmbuf_size - pcmbuffer_fillpos;
}
size_t pcmbuf_get_bufsize(void)
{
return pcmbuf_size;
}
int pcmbuf_used_descs(void)
{
struct chunkdesc *temp = read_chunk;
unsigned int i = 0;
while (temp) {
temp = temp->link;
i++;
}
return i;
}
int pcmbuf_descs(void)
{
return NUM_CHUNK_DESCS(pcmbuf_size);
}
#ifdef ROCKBOX_HAS_LOGF
unsigned char *pcmbuf_get_meminfo(size_t *length)
{
*length = pcmbuf_bufend - pcmbuffer;
return pcmbuffer;
}
#endif
/** Fading and channel volume control */
/* Sync the channel amplitude to all states */
static void pcmbuf_update_volume(void)
{
unsigned int vol = fade_vol;
if (soft_mode)
vol >>= 2;
mixer_channel_set_amplitude(PCM_MIXER_CHAN_PLAYBACK, vol);
}
/* Quiet-down the channel if 'shhh' is true or else play at normal level */
void pcmbuf_soft_mode(bool shhh)
{
soft_mode = shhh;
pcmbuf_update_volume();
}
/* Fade channel in or out */
void pcmbuf_fade(bool fade, bool in)
{
if (!fade)
{
/* Simply set the level */
fade_vol = in ? MIX_AMP_UNITY : MIX_AMP_MUTE;
}
else
{
/* Start from the opposing end */
fade_vol = in ? MIX_AMP_MUTE : MIX_AMP_UNITY;
}
pcmbuf_update_volume();
if (fade)
{
/* Do this on thread for now */
#ifdef HAVE_PRIORITY_SCHEDULING
int old_prio = thread_set_priority(thread_self(), PRIORITY_REALTIME);
#endif
while (1)
{
/* Linear fade actually sounds better */
if (in)
fade_vol += MIN(MIX_AMP_UNITY/16, MIX_AMP_UNITY - fade_vol);
else
fade_vol -= MIN(MIX_AMP_UNITY/16, fade_vol - MIX_AMP_MUTE);
pcmbuf_update_volume();
if (fade_vol > MIX_AMP_MUTE && fade_vol < MIX_AMP_UNITY)
{
sleep(0);
continue;
}
break;
}
#ifdef HAVE_PRIORITY_SCHEDULING
thread_set_priority(thread_self(), old_prio);
#endif
}
}
/** Misc */
bool pcmbuf_is_lowdata(void)
{
if (!pcm_is_playing() || pcm_is_paused()
#ifdef HAVE_CROSSFADE
|| pcmbuf_is_crossfade_active()
#endif
)
return false;
#if MEMORYSIZE > 2
/* 1 seconds of buffer is low data */
return LOW_DATA(4);
#else
/* under watermark is low data */
return (pcmbuf_unplayed_bytes < pcmbuf_watermark);
#endif
}
void pcmbuf_set_low_latency(bool state)
{
low_latency_mode = state;
}
unsigned long pcmbuf_get_latency(void)
{
return (pcmbuf_unplayed_bytes +
mixer_channel_get_bytes_waiting(PCM_MIXER_CHAN_PLAYBACK)) * 1000 / BYTERATE;
}