ffmpeg/libavdevice/jack_audio.c
Nicolas George 3073aadf2d timefilter: internally compute feedback factors.
The feedback factors for the timefilter are directly computed from
the expected period. This commit changes the init function to accept
the period itself and compute the feedback factors internally,
rather than having all client code duplicate the formulas.

This commit also actually fixes the formulas: the current code had
sqrt(2*o), but the correct formula, both theoretically and according
to experimental testing, is sqrt(2)*o.

Furthermore, it adds an exponential to feedback factors larger than
1 with large periods.
2012-03-05 16:57:27 +01:00

337 lines
11 KiB
C

/*
* JACK Audio Connection Kit input device
* Copyright (c) 2009 Samalyse
* Author: Olivier Guilyardi <olivier samalyse com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <semaphore.h>
#include <jack/jack.h>
#include "libavutil/log.h"
#include "libavutil/fifo.h"
#include "libavutil/opt.h"
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavformat/internal.h"
#include "timefilter.h"
#include "avdevice.h"
/**
* Size of the internal FIFO buffers as a number of audio packets
*/
#define FIFO_PACKETS_NUM 16
typedef struct {
AVClass *class;
jack_client_t * client;
int activated;
sem_t packet_count;
jack_nframes_t sample_rate;
jack_nframes_t buffer_size;
jack_port_t ** ports;
int nports;
TimeFilter * timefilter;
AVFifoBuffer * new_pkts;
AVFifoBuffer * filled_pkts;
int pkt_xrun;
int jack_xrun;
} JackData;
static int process_callback(jack_nframes_t nframes, void *arg)
{
/* Warning: this function runs in realtime. One mustn't allocate memory here
* or do any other thing that could block. */
int i, j;
JackData *self = arg;
float * buffer;
jack_nframes_t latency, cycle_delay;
AVPacket pkt;
float *pkt_data;
double cycle_time;
if (!self->client)
return 0;
/* The approximate delay since the hardware interrupt as a number of frames */
cycle_delay = jack_frames_since_cycle_start(self->client);
/* Retrieve filtered cycle time */
cycle_time = ff_timefilter_update(self->timefilter,
av_gettime() / 1000000.0 - (double) cycle_delay / self->sample_rate,
self->buffer_size);
/* Check if an empty packet is available, and if there's enough space to send it back once filled */
if ((av_fifo_size(self->new_pkts) < sizeof(pkt)) || (av_fifo_space(self->filled_pkts) < sizeof(pkt))) {
self->pkt_xrun = 1;
return 0;
}
/* Retrieve empty (but allocated) packet */
av_fifo_generic_read(self->new_pkts, &pkt, sizeof(pkt), NULL);
pkt_data = (float *) pkt.data;
latency = 0;
/* Copy and interleave audio data from the JACK buffer into the packet */
for (i = 0; i < self->nports; i++) {
latency += jack_port_get_total_latency(self->client, self->ports[i]);
buffer = jack_port_get_buffer(self->ports[i], self->buffer_size);
for (j = 0; j < self->buffer_size; j++)
pkt_data[j * self->nports + i] = buffer[j];
}
/* Timestamp the packet with the cycle start time minus the average latency */
pkt.pts = (cycle_time - (double) latency / (self->nports * self->sample_rate)) * 1000000.0;
/* Send the now filled packet back, and increase packet counter */
av_fifo_generic_write(self->filled_pkts, &pkt, sizeof(pkt), NULL);
sem_post(&self->packet_count);
return 0;
}
static void shutdown_callback(void *arg)
{
JackData *self = arg;
self->client = NULL;
}
static int xrun_callback(void *arg)
{
JackData *self = arg;
self->jack_xrun = 1;
ff_timefilter_reset(self->timefilter);
return 0;
}
static int supply_new_packets(JackData *self, AVFormatContext *context)
{
AVPacket pkt;
int test, pkt_size = self->buffer_size * self->nports * sizeof(float);
/* Supply the process callback with new empty packets, by filling the new
* packets FIFO buffer with as many packets as possible. process_callback()
* can't do this by itself, because it can't allocate memory in realtime. */
while (av_fifo_space(self->new_pkts) >= sizeof(pkt)) {
if ((test = av_new_packet(&pkt, pkt_size)) < 0) {
av_log(context, AV_LOG_ERROR, "Could not create packet of size %d\n", pkt_size);
return test;
}
av_fifo_generic_write(self->new_pkts, &pkt, sizeof(pkt), NULL);
}
return 0;
}
static int start_jack(AVFormatContext *context)
{
JackData *self = context->priv_data;
jack_status_t status;
int i, test;
/* Register as a JACK client, using the context filename as client name. */
self->client = jack_client_open(context->filename, JackNullOption, &status);
if (!self->client) {
av_log(context, AV_LOG_ERROR, "Unable to register as a JACK client\n");
return AVERROR(EIO);
}
sem_init(&self->packet_count, 0, 0);
self->sample_rate = jack_get_sample_rate(self->client);
self->ports = av_malloc(self->nports * sizeof(*self->ports));
self->buffer_size = jack_get_buffer_size(self->client);
/* Register JACK ports */
for (i = 0; i < self->nports; i++) {
char str[16];
snprintf(str, sizeof(str), "input_%d", i + 1);
self->ports[i] = jack_port_register(self->client, str,
JACK_DEFAULT_AUDIO_TYPE,
JackPortIsInput, 0);
if (!self->ports[i]) {
av_log(context, AV_LOG_ERROR, "Unable to register port %s:%s\n",
context->filename, str);
jack_client_close(self->client);
return AVERROR(EIO);
}
}
/* Register JACK callbacks */
jack_set_process_callback(self->client, process_callback, self);
jack_on_shutdown(self->client, shutdown_callback, self);
jack_set_xrun_callback(self->client, xrun_callback, self);
/* Create time filter */
self->timefilter = ff_timefilter_new (1.0 / self->sample_rate, self->buffer_size, 1.5);
/* Create FIFO buffers */
self->filled_pkts = av_fifo_alloc(FIFO_PACKETS_NUM * sizeof(AVPacket));
/* New packets FIFO with one extra packet for safety against underruns */
self->new_pkts = av_fifo_alloc((FIFO_PACKETS_NUM + 1) * sizeof(AVPacket));
if ((test = supply_new_packets(self, context))) {
jack_client_close(self->client);
return test;
}
return 0;
}
static void free_pkt_fifo(AVFifoBuffer *fifo)
{
AVPacket pkt;
while (av_fifo_size(fifo)) {
av_fifo_generic_read(fifo, &pkt, sizeof(pkt), NULL);
av_free_packet(&pkt);
}
av_fifo_free(fifo);
}
static void stop_jack(JackData *self)
{
if (self->client) {
if (self->activated)
jack_deactivate(self->client);
jack_client_close(self->client);
}
sem_destroy(&self->packet_count);
free_pkt_fifo(self->new_pkts);
free_pkt_fifo(self->filled_pkts);
av_freep(&self->ports);
ff_timefilter_destroy(self->timefilter);
}
static int audio_read_header(AVFormatContext *context)
{
JackData *self = context->priv_data;
AVStream *stream;
int test;
if ((test = start_jack(context)))
return test;
stream = avformat_new_stream(context, NULL);
if (!stream) {
stop_jack(self);
return AVERROR(ENOMEM);
}
stream->codec->codec_type = AVMEDIA_TYPE_AUDIO;
#if HAVE_BIGENDIAN
stream->codec->codec_id = CODEC_ID_PCM_F32BE;
#else
stream->codec->codec_id = CODEC_ID_PCM_F32LE;
#endif
stream->codec->sample_rate = self->sample_rate;
stream->codec->channels = self->nports;
avpriv_set_pts_info(stream, 64, 1, 1000000); /* 64 bits pts in us */
return 0;
}
static int audio_read_packet(AVFormatContext *context, AVPacket *pkt)
{
JackData *self = context->priv_data;
struct timespec timeout = {0, 0};
int test;
/* Activate the JACK client on first packet read. Activating the JACK client
* means that process_callback() starts to get called at regular interval.
* If we activate it in audio_read_header(), we're actually reading audio data
* from the device before instructed to, and that may result in an overrun. */
if (!self->activated) {
if (!jack_activate(self->client)) {
self->activated = 1;
av_log(context, AV_LOG_INFO,
"JACK client registered and activated (rate=%dHz, buffer_size=%d frames)\n",
self->sample_rate, self->buffer_size);
} else {
av_log(context, AV_LOG_ERROR, "Unable to activate JACK client\n");
return AVERROR(EIO);
}
}
/* Wait for a packet coming back from process_callback(), if one isn't available yet */
timeout.tv_sec = av_gettime() / 1000000 + 2;
if (sem_timedwait(&self->packet_count, &timeout)) {
if (errno == ETIMEDOUT) {
av_log(context, AV_LOG_ERROR,
"Input error: timed out when waiting for JACK process callback output\n");
} else {
av_log(context, AV_LOG_ERROR, "Error while waiting for audio packet: %s\n",
strerror(errno));
}
if (!self->client)
av_log(context, AV_LOG_ERROR, "Input error: JACK server is gone\n");
return AVERROR(EIO);
}
if (self->pkt_xrun) {
av_log(context, AV_LOG_WARNING, "Audio packet xrun\n");
self->pkt_xrun = 0;
}
if (self->jack_xrun) {
av_log(context, AV_LOG_WARNING, "JACK xrun\n");
self->jack_xrun = 0;
}
/* Retrieve the packet filled with audio data by process_callback() */
av_fifo_generic_read(self->filled_pkts, pkt, sizeof(*pkt), NULL);
if ((test = supply_new_packets(self, context)))
return test;
return 0;
}
static int audio_read_close(AVFormatContext *context)
{
JackData *self = context->priv_data;
stop_jack(self);
return 0;
}
#define OFFSET(x) offsetof(JackData, x)
static const AVOption options[] = {
{ "channels", "Number of audio channels.", OFFSET(nports), AV_OPT_TYPE_INT, { 2 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
{ NULL },
};
static const AVClass jack_indev_class = {
.class_name = "JACK indev",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVInputFormat ff_jack_demuxer = {
.name = "jack",
.long_name = NULL_IF_CONFIG_SMALL("JACK Audio Connection Kit"),
.priv_data_size = sizeof(JackData),
.read_header = audio_read_header,
.read_packet = audio_read_packet,
.read_close = audio_read_close,
.flags = AVFMT_NOFILE,
.priv_class = &jack_indev_class,
};