libao2/ao_jack.c

   1 /*
   2  * ao_jack.c - libao2 JACK Audio Output Driver for MPlayer
   3  *
   4  * This driver is under the same license as MPlayer.
   5  * (http://www.mplayerhq.hu)
   6  *
   7  * Copyleft 2001 by Felix Bünemann (atmosfear@users.sf.net)
   8  * and Reimar Döffinger (Reimar.Doeffinger@stud.uni-karlsruhe.de)
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <unistd.h>
  15
  16 #include "config.h"
  17 #include "mp_msg.h"
  18 #include "help_mp.h"
  19
  20 #include "audio_out.h"
  21 #include "audio_out_internal.h"
  22 #include "libaf/af_format.h"
  23 #include "osdep/timer.h"
  24 #include "subopt-helper.h"
  25
  26 #include "libvo/fastmemcpy.h"
  27
  28 #include <jack/jack.h>
  29
  30 static ao_info_t info =
  31 {
  32   "JACK audio output",
  33   "jack",
  34   "Reimar Döffinger <Reimar.Doeffinger@stud.uni-karlsruhe.de>",
  35   "based on ao_sdl.c"
  36 };
  37
  38 LIBAO_EXTERN(jack)
  39
  40 //! maximum number of channels supported, avoids lots of mallocs
  41 #define MAX_CHANS 6
  42 static jack_port_t *ports[MAX_CHANS];
  43 static int num_ports; ///< Number of used ports == number of channels
  44 static jack_client_t *client;
  45 static float jack_latency;
  46 static int estimate;
  47 static volatile int paused = 0; ///< set if paused
  48 static volatile int underrun = 0; ///< signals if an underrun occured
  49
  50 static volatile float callback_interval = 0;
  51 static volatile float callback_time = 0;
  52
  53 //! size of one chunk, if this is too small MPlayer will start to "stutter"
  54 //! after a short time of playback
  55 #define CHUNK_SIZE (16 * 1024)
  56 //! number of "virtual" chunks the buffer consists of
  57 #define NUM_CHUNKS 8
  58 // This type of ring buffer may never fill up completely, at least
  59 // one byte must always be unused.
  60 // For performance reasons (alignment etc.) one whole chunk always stays
  61 // empty, not only one byte.
  62 #define BUFFSIZE ((NUM_CHUNKS + 1) * CHUNK_SIZE)
  63
  64 //! buffer for audio data
  65 static unsigned char *buffer = NULL;
  66
  67 //! buffer read position, may only be modified by playback thread or while it is stopped
  68 static volatile int read_pos;
  69 //! buffer write position, may only be modified by MPlayer's thread
  70 static volatile int write_pos;
  71
  72 /**
  73  * \brief get the number of free bytes in the buffer
  74  * \return number of free bytes in buffer
  75  *
  76  * may only be called by MPlayer's thread
  77  * return value may change between immediately following two calls,
  78  * and the real number of free bytes might be larger!
  79  */
  80 static int buf_free(void) {
  81   int free = read_pos - write_pos - CHUNK_SIZE;
  82   if (free < 0) free += BUFFSIZE;
  83   return free;
  84 }
  85
  86 /**
  87  * \brief get amount of data available in the buffer
  88  * \return number of bytes available in buffer
  89  *
  90  * may only be called by the playback thread
  91  * return value may change between immediately following two calls,
  92  * and the real number of buffered bytes might be larger!
  93  */
  94 static int buf_used(void) {
  95   int used = write_pos - read_pos;
  96   if (used < 0) used += BUFFSIZE;
  97   return used;
  98 }
  99
 100 /**
 101  * \brief insert len bytes into buffer
 102  * \param data data to insert
 103  * \param len length of data
 104  * \return number of bytes inserted into buffer
 105  *
 106  * If there is not enough room, the buffer is filled up
 107  */
 108 static int write_buffer(unsigned char* data, int len) {
 109   int first_len = BUFFSIZE - write_pos;
 110   int free = buf_free();
 111   if (len > free) len = free;
 112   if (first_len > len) first_len = len;
 113   // till end of buffer
 114   fast_memcpy (&buffer[write_pos], data, first_len);
 115   if (len > first_len) { // we have to wrap around
 116     // remaining part from beginning of buffer
 117     fast_memcpy (buffer, &data[first_len], len - first_len);
 118   }
 119   write_pos = (write_pos + len) % BUFFSIZE;
 120   return len;
 121 }
 122
 123 static void silence(float **bufs, int cnt, int num_bufs);
 124
 125 /**
 126  * \brief read data from buffer and splitting it into channels
 127  * \param bufs num_bufs float buffers, each will contain the data of one channel
 128  * \param cnt number of samples to read per channel
 129  * \param num_bufs number of channels to split the data into
 130  * \return number of samples read per channel, equals cnt unless there was too
 131  *         little data in the buffer
 132  *
 133  * Assumes the data in the buffer is of type float, the number of bytes
 134  * read is res * num_bufs * sizeof(float), where res is the return value.
 135  * If there is not enough data in the buffer remaining parts will be filled
 136  * with silence.
 137  */
 138 static int read_buffer(float **bufs, int cnt, int num_bufs) {
 139   int buffered = buf_used();
 140   int i, j;
 141   if (cnt * sizeof(float) * num_bufs > buffered) {
 142     silence(bufs, cnt, num_bufs);
 143     cnt = buffered / sizeof(float) / num_bufs;
 144   }
 145   for (i = 0; i < cnt; i++) {
 146     for (j = 0; j < num_bufs; j++) {
 147       bufs[j][i] = *(float *)&buffer[read_pos];
 148       read_pos = (read_pos + sizeof(float)) % BUFFSIZE;
 149     }
 150   }
 151   return cnt;
 152 }
 153
 154 // end ring buffer stuff
 155
 156 static int control(int cmd, void *arg) {
 157   return CONTROL_UNKNOWN;
 158 }
 159
 160 /**
 161  * \brief fill the buffers with silence
 162  * \param bufs num_bufs float buffers, each will contain the data of one channel
 163  * \param cnt number of samples in each buffer
 164  * \param num_bufs number of buffers
 165  */
 166 static void silence(float **bufs, int cnt, int num_bufs) {
 167   int i;
 168   for (i = 0; i < num_bufs; i++)
 169     memset(bufs[i], 0, cnt * sizeof(float));
 170 }
 171
 172 /**
 173  * \brief JACK Callback function
 174  * \param nframes number of frames to fill into buffers
 175  * \param arg unused
 176  * \return currently always 0
 177  *
 178  * Write silence into buffers if paused or an underrun occured
 179  */
 180 static int outputaudio(jack_nframes_t nframes, void *arg) {
 181   float *bufs[MAX_CHANS];
 182   int i;
 183   for (i = 0; i < num_ports; i++)
 184     bufs[i] = jack_port_get_buffer(ports[i], nframes);
 185   if (paused || underrun)
 186     silence(bufs, nframes, num_ports);
 187   else
 188     if (read_buffer(bufs, nframes, num_ports) < nframes)
 189       underrun = 1;
 190   if (estimate) {
 191     float now = (float)GetTimer() / 1000000.0;
 192     float diff = callback_time + callback_interval - now;
 193     if ((diff > -0.002) && (diff < 0.002))
 194       callback_time += callback_interval;
 195     else
 196       callback_time = now;
 197     callback_interval = (float)nframes / (float)ao_data.samplerate;
 198   }
 199   return 0;
 200 }
 201
 202 /**
 203  * \brief print suboption usage help
 204  */
 205 static void print_help (void)
 206 {
 207   mp_msg (MSGT_AO, MSGL_FATAL,
 208            "\n-ao jack commandline help:\n"
 209            "Example: mplayer -ao jack:port=myout\n"
 210            "  connects MPlayer to the jack ports named myout\n"
 211            "\nOptions:\n"
 212            "  port=<port name>\n"
 213            "    Connects to the given ports instead of the default physical ones\n"
 214            "  name=<client name>\n"
 215            "    Client name to pass to JACK\n"
 216            "  estimate\n"
 217            "    Estimates the amount of data in buffers (experimental)\n");
 218 }
 219
 220 static int init(int rate, int channels, int format, int flags) {
 221   const char **matching_ports = NULL;
 222   char *port_name = NULL;
 223   char *client_name = NULL;
 224   opt_t subopts[] = {
 225     {"port", OPT_ARG_MSTRZ, &port_name, NULL},
 226     {"name", OPT_ARG_MSTRZ, &client_name, NULL},
 227     {"estimate", OPT_ARG_BOOL, &estimate, NULL},
 228     {NULL}
 229   };
 230   int port_flags = JackPortIsInput;
 231   int i;
 232   estimate = 1;
 233   if (subopt_parse(ao_subdevice, subopts) != 0) {
 234     print_help();
 235     return 0;
 236   }
 237   if (channels > MAX_CHANS) {
 238     mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] Invalid number of channels: %i\n", channels);
 239     goto err_out;
 240   }
 241   if (!client_name) {
 242     client_name = malloc(40);
 243     sprintf(client_name, "MPlayer [%d]", getpid());
 244   }
 245   client = jack_client_new(client_name);
 246   if (!client) {
 247     mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] cannot open server\n");
 248     goto err_out;
 249   }
 250   reset();
 251   jack_set_process_callback(client, outputaudio, 0);
 252
 253   // list matching ports
 254   if (!port_name)
 255     port_flags |= JackPortIsPhysical;
 256   matching_ports = jack_get_ports(client, port_name, NULL, port_flags);
 257   if (!matching_ports || !matching_ports[0]) {
 258     mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] no physical ports available\n");
 259     goto err_out;
 260   }
 261   i = 1;
 262   while (matching_ports[i]) i++;
 263   if (channels > i) channels = i;
 264   num_ports = channels;
 265
 266   // create out output ports
 267   for (i = 0; i < num_ports; i++) {
 268     char pname[30];
 269     snprintf(pname, 30, "out_%d", i);
 270     ports[i] = jack_port_register(client, pname, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
 271     if (!ports[i]) {
 272       mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] not enough ports available\n");
 273       goto err_out;
 274     }
 275   }
 276   if (jack_activate(client)) {
 277     mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] activate failed\n");
 278     goto err_out;
 279   }
 280   for (i = 0; i < num_ports; i++) {
 281     if (jack_connect(client, jack_port_name(ports[i]), matching_ports[i])) {
 282       mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] connecting failed\n");
 283       goto err_out;
 284     }
 285   }
 286   rate = jack_get_sample_rate(client);
 287   jack_latency = (float)(jack_port_get_total_latency(client, ports[0]) +
 288                          jack_get_buffer_size(client)) / (float)rate;
 289   callback_interval = 0;
 290   buffer = malloc(BUFFSIZE);
 291
 292   ao_data.channels = channels;
 293   ao_data.samplerate = rate;
 294   ao_data.format = AF_FORMAT_FLOAT_NE;
 295   ao_data.bps = channels * rate * sizeof(float);
 296   ao_data.buffersize = CHUNK_SIZE * NUM_CHUNKS;
 297   ao_data.outburst = CHUNK_SIZE;
 298   free(matching_ports);
 299   free(port_name);
 300   free(client_name);
 301   return 1;
 302
 303 err_out:
 304   free(matching_ports);
 305   free(port_name);
 306   free(client_name);
 307   if (client)
 308     jack_client_close(client);
 309   free(buffer);
 310   buffer = NULL;
 311   return 0;
 312 }
 313
 314 // close audio device
 315 static void uninit(int immed) {
 316   if (!immed)
 317     usec_sleep(get_delay() * 1000 * 1000);
 318   // HACK, make sure jack doesn't loop-output dirty buffers
 319   reset();
 320   usec_sleep(100 * 1000);
 321   jack_client_close(client);
 322   free(buffer);
 323   buffer = NULL;
 324 }
 325
 326 /**
 327  * \brief stop playing and empty buffers (for seeking/pause)
 328  */
 329 static void reset(void) {
 330   paused = 1;
 331   read_pos = 0;
 332   write_pos = 0;
 333   paused = 0;
 334 }
 335
 336 /**
 337  * \brief stop playing, keep buffers (for pause)
 338  */
 339 static void audio_pause(void) {
 340   paused = 1;
 341 }
 342
 343 /**
 344  * \brief resume playing, after audio_pause()
 345  */
 346 static void audio_resume(void) {
 347   paused = 0;
 348 }
 349
 350 static int get_space(void) {
 351   return buf_free();
 352 }
 353
 354 /**
 355  * \brief write data into buffer and reset underrun flag
 356  */
 357 static int play(void *data, int len, int flags) {
 358   if (!(flags & AOPLAY_FINAL_CHUNK))
 359     len -= len % ao_data.outburst;
 360   underrun = 0;
 361   return write_buffer(data, len);
 362 }
 363
 364 static float get_delay(void) {
 365   int buffered = BUFFSIZE - CHUNK_SIZE - buf_free(); // could be less
 366   float in_jack = jack_latency;
 367   if (estimate && callback_interval > 0) {
 368     float elapsed = (float)GetTimer() / 1000000.0 - callback_time;
 369     in_jack += callback_interval - elapsed;
 370     if (in_jack < 0) in_jack = 0;
 371   }
 372   return (float)buffered / (float)ao_data.bps + in_jack;
 373 }
 374