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jack.c
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1 /*
2  * JACK Audio Connection Kit input device
3  * Copyright (c) 2009 Samalyse
4  * Author: Olivier Guilyardi <olivier samalyse com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "config.h"
24 #include <semaphore.h>
25 #include <jack/jack.h>
26 
27 #include "libavutil/internal.h"
28 #include "libavutil/log.h"
29 #include "libavutil/fifo.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/time.h"
32 #include "libavcodec/avcodec.h"
33 #include "libavformat/avformat.h"
34 #include "libavformat/internal.h"
35 #include "timefilter.h"
36 #include "avdevice.h"
37 
38 /**
39  * Size of the internal FIFO buffers as a number of audio packets
40  */
41 #define FIFO_PACKETS_NUM 16
42 
43 typedef struct JackData {
44  AVClass *class;
45  jack_client_t * client;
46  int activated;
47  sem_t packet_count;
48  jack_nframes_t sample_rate;
49  jack_nframes_t buffer_size;
50  jack_port_t ** ports;
51  int nports;
55  int pkt_xrun;
56  int jack_xrun;
57 } JackData;
58 
59 static int process_callback(jack_nframes_t nframes, void *arg)
60 {
61  /* Warning: this function runs in realtime. One mustn't allocate memory here
62  * or do any other thing that could block. */
63 
64  int i, j;
65  JackData *self = arg;
66  float * buffer;
67  jack_nframes_t latency, cycle_delay;
68  AVPacket pkt;
69  float *pkt_data;
70  double cycle_time;
71 
72  if (!self->client)
73  return 0;
74 
75  /* The approximate delay since the hardware interrupt as a number of frames */
76  cycle_delay = jack_frames_since_cycle_start(self->client);
77 
78  /* Retrieve filtered cycle time */
79  cycle_time = ff_timefilter_update(self->timefilter,
80  av_gettime() / 1000000.0 - (double) cycle_delay / self->sample_rate,
81  self->buffer_size);
82 
83  /* Check if an empty packet is available, and if there's enough space to send it back once filled */
84  if ((av_fifo_size(self->new_pkts) < sizeof(pkt)) || (av_fifo_space(self->filled_pkts) < sizeof(pkt))) {
85  self->pkt_xrun = 1;
86  return 0;
87  }
88 
89  /* Retrieve empty (but allocated) packet */
90  av_fifo_generic_read(self->new_pkts, &pkt, sizeof(pkt), NULL);
91 
92  pkt_data = (float *) pkt.data;
93  latency = 0;
94 
95  /* Copy and interleave audio data from the JACK buffer into the packet */
96  for (i = 0; i < self->nports; i++) {
97  #if HAVE_JACK_PORT_GET_LATENCY_RANGE
98  jack_latency_range_t range;
99  jack_port_get_latency_range(self->ports[i], JackCaptureLatency, &range);
100  latency += range.max;
101  #else
102  latency += jack_port_get_total_latency(self->client, self->ports[i]);
103  #endif
104  buffer = jack_port_get_buffer(self->ports[i], self->buffer_size);
105  for (j = 0; j < self->buffer_size; j++)
106  pkt_data[j * self->nports + i] = buffer[j];
107  }
108 
109  /* Timestamp the packet with the cycle start time minus the average latency */
110  pkt.pts = (cycle_time - (double) latency / (self->nports * self->sample_rate)) * 1000000.0;
111 
112  /* Send the now filled packet back, and increase packet counter */
113  av_fifo_generic_write(self->filled_pkts, &pkt, sizeof(pkt), NULL);
114  sem_post(&self->packet_count);
115 
116  return 0;
117 }
118 
119 static void shutdown_callback(void *arg)
120 {
121  JackData *self = arg;
122  self->client = NULL;
123 }
124 
125 static int xrun_callback(void *arg)
126 {
127  JackData *self = arg;
128  self->jack_xrun = 1;
129  ff_timefilter_reset(self->timefilter);
130  return 0;
131 }
132 
133 static int supply_new_packets(JackData *self, AVFormatContext *context)
134 {
135  AVPacket pkt;
136  int test, pkt_size = self->buffer_size * self->nports * sizeof(float);
137 
138  /* Supply the process callback with new empty packets, by filling the new
139  * packets FIFO buffer with as many packets as possible. process_callback()
140  * can't do this by itself, because it can't allocate memory in realtime. */
141  while (av_fifo_space(self->new_pkts) >= sizeof(pkt)) {
142  if ((test = av_new_packet(&pkt, pkt_size)) < 0) {
143  av_log(context, AV_LOG_ERROR, "Could not create packet of size %d\n", pkt_size);
144  return test;
145  }
146  av_fifo_generic_write(self->new_pkts, &pkt, sizeof(pkt), NULL);
147  }
148  return 0;
149 }
150 
151 static int start_jack(AVFormatContext *context)
152 {
153  JackData *self = context->priv_data;
154  jack_status_t status;
155  int i, test;
156 
157  /* Register as a JACK client, using the context filename as client name. */
158  self->client = jack_client_open(context->filename, JackNullOption, &status);
159  if (!self->client) {
160  av_log(context, AV_LOG_ERROR, "Unable to register as a JACK client\n");
161  return AVERROR(EIO);
162  }
163 
164  sem_init(&self->packet_count, 0, 0);
165 
166  self->sample_rate = jack_get_sample_rate(self->client);
167  self->ports = av_malloc_array(self->nports, sizeof(*self->ports));
168  if (!self->ports)
169  return AVERROR(ENOMEM);
170  self->buffer_size = jack_get_buffer_size(self->client);
171 
172  /* Register JACK ports */
173  for (i = 0; i < self->nports; i++) {
174  char str[16];
175  snprintf(str, sizeof(str), "input_%d", i + 1);
176  self->ports[i] = jack_port_register(self->client, str,
177  JACK_DEFAULT_AUDIO_TYPE,
178  JackPortIsInput, 0);
179  if (!self->ports[i]) {
180  av_log(context, AV_LOG_ERROR, "Unable to register port %s:%s\n",
181  context->filename, str);
182  jack_client_close(self->client);
183  return AVERROR(EIO);
184  }
185  }
186 
187  /* Register JACK callbacks */
188  jack_set_process_callback(self->client, process_callback, self);
189  jack_on_shutdown(self->client, shutdown_callback, self);
190  jack_set_xrun_callback(self->client, xrun_callback, self);
191 
192  /* Create time filter */
193  self->timefilter = ff_timefilter_new (1.0 / self->sample_rate, self->buffer_size, 1.5);
194  if (!self->timefilter) {
195  jack_client_close(self->client);
196  return AVERROR(ENOMEM);
197  }
198 
199  /* Create FIFO buffers */
200  self->filled_pkts = av_fifo_alloc_array(FIFO_PACKETS_NUM, sizeof(AVPacket));
201  /* New packets FIFO with one extra packet for safety against underruns */
202  self->new_pkts = av_fifo_alloc_array((FIFO_PACKETS_NUM + 1), sizeof(AVPacket));
203  if (!self->new_pkts) {
204  jack_client_close(self->client);
205  return AVERROR(ENOMEM);
206  }
207  if ((test = supply_new_packets(self, context))) {
208  jack_client_close(self->client);
209  return test;
210  }
211 
212  return 0;
213 
214 }
215 
216 static void free_pkt_fifo(AVFifoBuffer **fifo)
217 {
218  AVPacket pkt;
219  while (av_fifo_size(*fifo)) {
220  av_fifo_generic_read(*fifo, &pkt, sizeof(pkt), NULL);
221  av_free_packet(&pkt);
222  }
223  av_fifo_freep(fifo);
224 }
225 
226 static void stop_jack(JackData *self)
227 {
228  if (self->client) {
229  if (self->activated)
230  jack_deactivate(self->client);
231  jack_client_close(self->client);
232  }
233  sem_destroy(&self->packet_count);
234  free_pkt_fifo(&self->new_pkts);
235  free_pkt_fifo(&self->filled_pkts);
236  av_freep(&self->ports);
237  ff_timefilter_destroy(self->timefilter);
238 }
239 
240 static int audio_read_header(AVFormatContext *context)
241 {
242  JackData *self = context->priv_data;
243  AVStream *stream;
244  int test;
245 
246  if ((test = start_jack(context)))
247  return test;
248 
249  stream = avformat_new_stream(context, NULL);
250  if (!stream) {
251  stop_jack(self);
252  return AVERROR(ENOMEM);
253  }
254 
256 #if HAVE_BIGENDIAN
258 #else
260 #endif
261  stream->codec->sample_rate = self->sample_rate;
262  stream->codec->channels = self->nports;
263 
264  avpriv_set_pts_info(stream, 64, 1, 1000000); /* 64 bits pts in us */
265  return 0;
266 }
267 
269 {
270  JackData *self = context->priv_data;
271  struct timespec timeout = {0, 0};
272  int test;
273 
274  /* Activate the JACK client on first packet read. Activating the JACK client
275  * means that process_callback() starts to get called at regular interval.
276  * If we activate it in audio_read_header(), we're actually reading audio data
277  * from the device before instructed to, and that may result in an overrun. */
278  if (!self->activated) {
279  if (!jack_activate(self->client)) {
280  self->activated = 1;
281  av_log(context, AV_LOG_INFO,
282  "JACK client registered and activated (rate=%dHz, buffer_size=%d frames)\n",
283  self->sample_rate, self->buffer_size);
284  } else {
285  av_log(context, AV_LOG_ERROR, "Unable to activate JACK client\n");
286  return AVERROR(EIO);
287  }
288  }
289 
290  /* Wait for a packet coming back from process_callback(), if one isn't available yet */
291  timeout.tv_sec = av_gettime() / 1000000 + 2;
292  if (sem_timedwait(&self->packet_count, &timeout)) {
293  if (errno == ETIMEDOUT) {
294  av_log(context, AV_LOG_ERROR,
295  "Input error: timed out when waiting for JACK process callback output\n");
296  } else {
297  char errbuf[128];
298  int ret = AVERROR(errno);
299  av_strerror(ret, errbuf, sizeof(errbuf));
300  av_log(context, AV_LOG_ERROR, "Error while waiting for audio packet: %s\n",
301  errbuf);
302  }
303  if (!self->client)
304  av_log(context, AV_LOG_ERROR, "Input error: JACK server is gone\n");
305 
306  return AVERROR(EIO);
307  }
308 
309  if (self->pkt_xrun) {
310  av_log(context, AV_LOG_WARNING, "Audio packet xrun\n");
311  self->pkt_xrun = 0;
312  }
313 
314  if (self->jack_xrun) {
315  av_log(context, AV_LOG_WARNING, "JACK xrun\n");
316  self->jack_xrun = 0;
317  }
318 
319  /* Retrieve the packet filled with audio data by process_callback() */
320  av_fifo_generic_read(self->filled_pkts, pkt, sizeof(*pkt), NULL);
321 
322  if ((test = supply_new_packets(self, context)))
323  return test;
324 
325  return 0;
326 }
327 
328 static int audio_read_close(AVFormatContext *context)
329 {
330  JackData *self = context->priv_data;
331  stop_jack(self);
332  return 0;
333 }
334 
335 #define OFFSET(x) offsetof(JackData, x)
336 static const AVOption options[] = {
337  { "channels", "Number of audio channels.", OFFSET(nports), AV_OPT_TYPE_INT, { .i64 = 2 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
338  { NULL },
339 };
340 
341 static const AVClass jack_indev_class = {
342  .class_name = "JACK indev",
343  .item_name = av_default_item_name,
344  .option = options,
345  .version = LIBAVUTIL_VERSION_INT,
347 };
348 
350  .name = "jack",
351  .long_name = NULL_IF_CONFIG_SMALL("JACK Audio Connection Kit"),
352  .priv_data_size = sizeof(JackData),
356  .flags = AVFMT_NOFILE,
357  .priv_class = &jack_indev_class,
358 };
jack_client_t * client
Definition: jack.c:45
#define NULL
Definition: coverity.c:32
int pkt_xrun
Definition: jack.c:55
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:280
AVOption.
Definition: opt.h:255
void ff_timefilter_destroy(TimeFilter *self)
Free all resources associated with the filter.
Definition: timefilter.c:62
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:62
void ff_timefilter_reset(TimeFilter *self)
Reset the filter.
Definition: timefilter.c:67
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4083
int jack_xrun
Definition: jack.c:56
static AVPacket pkt
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int(*func)(void *, void *, int))
Feed data from a user-supplied callback to an AVFifoBuffer.
Definition: fifo.c:122
Definition: jack.c:43
Format I/O context.
Definition: avformat.h:1273
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
Opaque type representing a time filter state.
Definition: timefilter.c:30
AVOptions.
static int supply_new_packets(JackData *self, AVFormatContext *context)
Definition: jack.c:133
int av_fifo_space(const AVFifoBuffer *f)
Return the amount of space in bytes in the AVFifoBuffer, that is the amount of data you can write int...
Definition: fifo.c:82
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3749
AVInputFormat ff_jack_demuxer
Definition: jack.c:349
AVFifoBuffer * filled_pkts
Definition: jack.c:54
static void free_pkt_fifo(AVFifoBuffer **fifo)
Definition: jack.c:216
jack_port_t ** ports
Definition: jack.c:50
uint8_t * data
Definition: avcodec.h:1423
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
#define FIFO_PACKETS_NUM
Size of the internal FIFO buffers as a number of audio packets.
Definition: jack.c:41
#define av_log(a,...)
Main libavdevice API header.
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:83
int nports
Definition: jack.c:51
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void(*func)(void *, void *, int))
Feed data from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:177
static const AVOption options[]
Definition: jack.c:336
const char * arg
Definition: jacosubdec.c:66
Libavcodec external API header.
static int start_jack(AVFormatContext *context)
Definition: jack.c:151
int activated
Definition: jack.c:46
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
common internal API header
char filename[1024]
input or output filename
Definition: avformat.h:1349
static void test(const char *pattern, const char *host)
Definition: noproxy-test.c:23
sem_t packet_count
Definition: jack.c:47
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:623
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
Stream structure.
Definition: avformat.h:842
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
TimeFilter * ff_timefilter_new(double time_base, double period, double bandwidth)
Create a new Delay Locked Loop time filter.
Definition: timefilter.c:46
enum AVMediaType codec_type
Definition: avcodec.h:1510
static int audio_read_packet(AVFormatContext *context, AVPacket *pkt)
Definition: jack.c:268
enum AVCodecID codec_id
Definition: avcodec.h:1519
int av_fifo_size(const AVFifoBuffer *f)
Return the amount of data in bytes in the AVFifoBuffer, that is the amount of data you can read from ...
Definition: fifo.c:77
int sample_rate
samples per second
Definition: avcodec.h:2262
jack_nframes_t sample_rate
Definition: jack.c:48
a very simple circular buffer FIFO implementation
Describe the class of an AVClass context structure.
Definition: log.h:67
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:286
#define snprintf
Definition: snprintf.h:34
#define OFFSET(x)
Definition: jack.c:335
static int process_callback(jack_nframes_t nframes, void *arg)
Definition: jack.c:59
static void shutdown_callback(void *arg)
Definition: jack.c:119
AVFifoBuffer * av_fifo_alloc_array(size_t nmemb, size_t size)
Initialize an AVFifoBuffer.
Definition: fifo.c:49
static int audio_read_close(AVFormatContext *context)
Definition: jack.c:328
static int flags
Definition: cpu.c:47
int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
Put a description of the AVERROR code errnum in errbuf.
Definition: error.c:68
TimeFilter * timefilter
Definition: jack.c:52
Main libavformat public API header.
double ff_timefilter_update(TimeFilter *self, double system_time, double period)
Update the filter.
Definition: timefilter.c:72
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:465
static int audio_read_header(AVFormatContext *context)
Definition: jack.c:240
static int xrun_callback(void *arg)
Definition: jack.c:125
static const AVClass jack_indev_class
Definition: jack.c:341
int channels
number of audio channels
Definition: avcodec.h:2263
void * priv_data
Format private data.
Definition: avformat.h:1301
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:628
void av_fifo_freep(AVFifoBuffer **f)
Free an AVFifoBuffer and reset pointer to NULL.
Definition: fifo.c:63
jack_nframes_t buffer_size
Definition: jack.c:49
#define av_malloc_array(a, b)
This structure stores compressed data.
Definition: avcodec.h:1400
static void stop_jack(JackData *self)
Definition: jack.c:226
AVFifoBuffer * new_pkts
Definition: jack.c:53
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1416
for(j=16;j >0;--j)
GLuint buffer
Definition: opengl_enc.c:102