libao2/ao_openal.c

   1 /*
   2  * ao_openal.c - OpenAL audio output driver for MPlayer
   3  *
   4  * This driver is under the same license as MPlayer.
   5  * (http://www.mplayerhq.hu)
   6  *
   7  * Copyleft 2006 by Reimar Döffinger (Reimar.Doeffinger@stud.uni-karlsruhe.de)
   8  */
   9
  10 #include <stdlib.h>
  11 #include <stdio.h>
  12 #include <inttypes.h>
  13 #include <AL/alc.h>
  14 #include <AL/al.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 static ao_info_t info =
  27 {
  28   "OpenAL audio output",
  29   "openal",
  30   "Reimar Döffinger <Reimar.Doeffinger@stud.uni-karlsruhe.de>",
  31   ""
  32 };
  33
  34 LIBAO_EXTERN(openal)
  35
  36 #define MAX_CHANS 6
  37 #define NUM_BUF 128
  38 #define CHUNK_SIZE 512
  39 static ALuint buffers[MAX_CHANS][NUM_BUF];
  40 static ALuint sources[MAX_CHANS];
  41
  42 static int cur_buf[MAX_CHANS];
  43 static int unqueue_buf[MAX_CHANS];
  44 static int16_t *tmpbuf;
  45
  46
  47 static int control(int cmd, void *arg) {
  48   return CONTROL_UNKNOWN;
  49 }
  50
  51 /**
  52  * \brief print suboption usage help
  53  */
  54 static void print_help(void) {
  55   mp_msg(MSGT_AO, MSGL_FATAL,
  56           "\n-ao openal commandline help:\n"
  57           "Example: mplayer -ao openal\n"
  58           "\nOptions:\n"
  59         );
  60 }
  61
  62 static int init(int rate, int channels, int format, int flags) {
  63   ALCdevice *dev = NULL;
  64   ALCcontext *ctx = NULL;
  65   ALint bufrate;
  66   int i;
  67   opt_t subopts[] = {
  68     {NULL}
  69   };
  70   if (subopt_parse(ao_subdevice, subopts) != 0) {
  71     print_help();
  72     return 0;
  73   }
  74   if (channels > MAX_CHANS) {
  75     mp_msg(MSGT_AO, MSGL_FATAL, "[OpenAL] Invalid number of channels: %i\n", channels);
  76     goto err_out;
  77   }
  78   dev = alcOpenDevice(NULL);
  79   if (!dev) {
  80     mp_msg(MSGT_AO, MSGL_FATAL, "[OpenAL] could not open device\n");
  81     goto err_out;
  82   }
  83   ctx = alcCreateContext(dev, NULL);
  84   alcMakeContextCurrent(ctx);
  85   for (i = 0; i < channels; i++) {
  86     cur_buf[i] = 0;
  87     unqueue_buf[i] = 0;
  88     alGenBuffers(NUM_BUF, buffers[i]);
  89   }
  90   alGenSources(channels, sources);
  91   alSource3f(sources[0], AL_POSITION, 0, 0, 10);
  92   ao_data.channels = channels;
  93   alGetBufferi(buffers[0][0], AL_FREQUENCY, &bufrate);
  94   ao_data.samplerate = rate = bufrate;
  95   ao_data.format = AF_FORMAT_S16_NE;
  96   ao_data.bps = channels * rate * 2;
  97   ao_data.buffersize = CHUNK_SIZE * NUM_BUF;
  98   ao_data.outburst = channels * CHUNK_SIZE;
  99   tmpbuf = malloc(CHUNK_SIZE);
 100   return 1;
 101
 102 err_out:
 103   return 0;
 104 }
 105
 106 // close audio device
 107 static void uninit(int immed) {
 108   ALCcontext *ctx = alcGetCurrentContext();
 109   ALCdevice *dev = alcGetContextsDevice(ctx);
 110   free(tmpbuf);
 111   if (!immed) {
 112     ALint state;
 113     alGetSourcei(sources[0], AL_SOURCE_STATE, &state);
 114     while (state == AL_PLAYING) {
 115       usec_sleep(10000);
 116       alGetSourcei(sources[0], AL_SOURCE_STATE, &state);
 117     }
 118   }
 119   reset();
 120   alcMakeContextCurrent(NULL);
 121   alcDestroyContext(ctx);
 122   alcCloseDevice(dev);
 123 }
 124
 125 static void unqueue_buffers(void) {
 126   ALint p;
 127   int s, i;
 128   for (s = 0;  s < ao_data.channels; s++) {
 129     alGetSourcei(sources[s], AL_BUFFERS_PROCESSED, &p);
 130     for (i = 0; i < p; i++) {
 131       alSourceUnqueueBuffers(sources[s], 1, &buffers[s][unqueue_buf[s]]);
 132       unqueue_buf[s] = (unqueue_buf[s] + 1) % NUM_BUF;
 133     }
 134   }
 135 }
 136
 137 /**
 138  * \brief stop playing and empty buffers (for seeking/pause)
 139  */
 140 static void reset(void) {
 141   alSourceRewindv(ao_data.channels, sources);
 142   unqueue_buffers();
 143 }
 144
 145 /**
 146  * \brief stop playing, keep buffers (for pause)
 147  */
 148 static void audio_pause(void) {
 149   alSourcePausev(ao_data.channels, sources);
 150 }
 151
 152 /**
 153  * \brief resume playing, after audio_pause()
 154  */
 155 static void audio_resume(void) {
 156   alSourcePlayv(ao_data.channels, sources);
 157 }
 158
 159 static int get_space(void) {
 160   ALint queued;
 161   unqueue_buffers();
 162   alGetSourcei(sources[0], AL_BUFFERS_QUEUED, &queued);
 163   return (NUM_BUF - queued) * CHUNK_SIZE * ao_data.channels;
 164 }
 165
 166 /**
 167  * \brief write data into buffer and reset underrun flag
 168  */
 169 static int play(void *data, int len, int flags) {
 170   ALint state;
 171   int i, j, k;
 172   int ch;
 173   int16_t *d = data;
 174   len /= ao_data.outburst;
 175   for (i = 0; i < len; i++) {
 176     for (ch = 0; ch < ao_data.channels; ch++) {
 177       for (j = 0, k = ch; j < CHUNK_SIZE / 2; j++, k += ao_data.channels)
 178         tmpbuf[j] = d[k];
 179       alBufferData(buffers[ch][cur_buf[ch]], AL_FORMAT_MONO16, tmpbuf,
 180                      CHUNK_SIZE, ao_data.samplerate);
 181       alSourceQueueBuffers(sources[ch], 1, &buffers[ch][cur_buf[ch]]);
 182       cur_buf[ch] = (cur_buf[ch] + 1) % NUM_BUF;
 183     }
 184     d += ao_data.channels * CHUNK_SIZE / 2;
 185   }
 186   alGetSourcei(sources[0], AL_SOURCE_STATE, &state);
 187   if (state != AL_PLAYING) // checked here in case of an underrun
 188     alSourcePlayv(ao_data.channels, sources);
 189   return len * ao_data.outburst;
 190 }
 191
 192 static float get_delay(void) {
 193   ALint queued;
 194   unqueue_buffers();
 195   alGetSourcei(sources[0], AL_BUFFERS_QUEUED, &queued);
 196   return queued * CHUNK_SIZE / 2 / (float)ao_data.samplerate;
 197 }
 198