/* Based on a plugin from Martin Soto's Seamless DVD Player. * Copyright (C) 2003, 2004 Martin Soto * 2005-6 Michael Smith * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include #include "alsaspdifsink.h" GST_DEBUG_CATEGORY_STATIC (alsaspdifsink_debug); #define GST_CAT_DEFAULT (alsaspdifsink_debug) /* The magic audio-type we pretend to be for AC3 output */ #define AC3_CHANNELS 2 #define AC3_BITS 16 /* Define AC3 FORMAT as big endian. Fall back to swapping * on sound devices that don't support it */ #define AC3_FORMAT_BE SND_PCM_FORMAT_S16_BE #define AC3_FORMAT_LE SND_PCM_FORMAT_S16_LE /* The size in bytes of an IEC958 frame. */ #define IEC958_FRAME_SIZE 6144 /* Size in bytes of an ALSA PCM frame (4, for this case). */ #define ALSASPDIFSINK_BYTES_PER_FRAME ((AC3_BITS / 8) * AC3_CHANNELS) #define IEC958_SAMPLES_PER_FRAME (IEC958_FRAME_SIZE / ALSASPDIFSINK_BYTES_PER_FRAME) #if 0 /* The duration of a single IEC958 frame. */ #define IEC958_FRAME_DURATION (32 * GST_MSECOND) /* Maximal synchronization difference. Measures will be taken if block timestamps differ from actual playing time in more than this value. */ #define MAX_SYNC_DIFF (IEC958_FRAME_DURATION * 0.8) /* Playing time for the given number of ALSA PCM frames. */ #define ALSASPDIFSINK_TIME_PER_FRAMES(sink, frames) \ (((GstClockTime) (frames) * GST_SECOND) / AC3_RATE) /* Number of ALSA PCM frames for the given playing time. */ #define ALSASPDIFSINK_FRAMES_PER_TIME(sink, time) \ (((GstClockTime) AC3_RATE * (time)) / GST_SECOND) #endif /* AlsaSPDIFSink signals and args */ enum { LAST_SIGNAL }; enum { PROP_0, PROP_CARD, PROP_DEVICE }; static GstStaticPadTemplate alsaspdifsink_sink_factory = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/x-iec958") ); #define _do_init(bla) \ GST_DEBUG_CATEGORY_INIT (alsaspdifsink_debug, "alsaspdifsink", 0, \ "ALSA S/PDIF audio sink element"); GST_BOILERPLATE_FULL (AlsaSPDIFSink, alsaspdifsink, GstBaseSink, GST_TYPE_BASE_SINK, _do_init); static void alsaspdifsink_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void alsaspdifsink_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static gboolean alsaspdifsink_event (GstBaseSink * bsink, GstEvent * event); static GstFlowReturn alsaspdifsink_render (GstBaseSink * bsink, GstBuffer * buf); static void alsaspdifsink_get_times (GstBaseSink * bsink, GstBuffer * buffer, GstClockTime * start, GstClockTime * end); static gboolean alsaspdifsink_set_caps (GstBaseSink * bsink, GstCaps * caps); static gboolean alsaspdifsink_open (AlsaSPDIFSink * sink); static void alsaspdifsink_close (AlsaSPDIFSink * sink); static GstClock *alsaspdifsink_provide_clock (GstElement * elem); static GstClockTime alsaspdifsink_get_time (GstClock * clock, gpointer user_data); static void alsaspdifsink_dispose (GObject * object); static void alsaspdifsink_finalize (GObject * object); static GstStateChangeReturn alsaspdifsink_change_state (GstElement * element, GstStateChange transition); static int alsaspdifsink_find_pcm_device (AlsaSPDIFSink * sink); static gboolean alsaspdifsink_set_params (AlsaSPDIFSink * sink); static snd_pcm_sframes_t alsaspdifsink_delay (AlsaSPDIFSink * sink); /* Alsa error handler to suppress messages from within the ALSA library */ static void ignore_alsa_err (const char *file, int line, const char *function, int err, const char *fmt, ...); static void alsaspdifsink_base_init (gpointer g_class) { GstElementClass *element_class = GST_ELEMENT_CLASS (g_class); gst_element_class_set_details_simple (element_class, "S/PDIF ALSA audiosink", "Sink/Audio", "Feeds audio to S/PDIF interfaces through the ALSA sound driver", "Martin Soto , " "Michael Smith "); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&alsaspdifsink_sink_factory)); } static void alsaspdifsink_class_init (AlsaSPDIFSinkClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; GstBaseSinkClass *gstbasesink_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gstbasesink_class = (GstBaseSinkClass *) klass; gobject_class->set_property = alsaspdifsink_set_property; gobject_class->get_property = alsaspdifsink_get_property; gobject_class->dispose = alsaspdifsink_dispose; gobject_class->finalize = alsaspdifsink_finalize; gstelement_class->change_state = alsaspdifsink_change_state; gstelement_class->provide_clock = alsaspdifsink_provide_clock; gstbasesink_class->event = alsaspdifsink_event; gstbasesink_class->render = alsaspdifsink_render; gstbasesink_class->get_times = alsaspdifsink_get_times; gstbasesink_class->set_caps = alsaspdifsink_set_caps; #if 0 /* We ignore the device property anyway, so don't install it * we don't want the user supplying just any device string for us. * At most we might want a card number and an iec958.%d device name * to attempt */ g_object_class_install_property (gobject_class, PROP_DEVICE, g_param_spec_string ("device", "Device", "ALSA device, as defined in an asound configuration file", "default", G_PARAM_READWRITE)); #endif g_object_class_install_property (gobject_class, PROP_CARD, g_param_spec_int ("card", "Card", "ALSA card number for the SPDIF device to use", 0, G_MAXINT, 0, G_PARAM_READWRITE)); snd_lib_error_set_handler (ignore_alsa_err); } static void alsaspdifsink_init (AlsaSPDIFSink * sink, AlsaSPDIFSinkClass * g_class) { /* Create the provided clock. */ #if GST_CHECK_VERSION(0, 10, 31) || (GST_CHECK_VERSION(0, 10, 30) && GST_VERSION_NANO > 0) sink->clock = gst_audio_clock_new_full ("clock", alsaspdifsink_get_time, gst_object_ref (sink), (GDestroyNotify) gst_object_unref); #else sink->clock = gst_audio_clock_new ("clock", alsaspdifsink_get_time, sink); #endif sink->card = 0; sink->device = g_strdup ("default"); } static void alsaspdifsink_dispose (GObject * object) { AlsaSPDIFSink *sink = ALSASPDIFSINK (object); if (sink->clock) gst_object_unref (sink->clock); sink->clock = NULL; G_OBJECT_CLASS (parent_class)->dispose (object); } static void alsaspdifsink_finalize (GObject * object) { AlsaSPDIFSink *sink = ALSASPDIFSINK (object); g_free (sink->device); sink->device = NULL; G_OBJECT_CLASS (parent_class)->finalize (object); } static void alsaspdifsink_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { AlsaSPDIFSink *sink; sink = ALSASPDIFSINK (object); switch (prop_id) { /* case PROP_DEVICE: if(sink->device) g_free(sink->device); sink->device = g_strdup(g_value_get_string(value)); break; */ case PROP_CARD: sink->card = g_value_get_int (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void alsaspdifsink_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { AlsaSPDIFSink *sink; sink = ALSASPDIFSINK (object); switch (prop_id) { /* case PROP_DEVICE: g_value_set_string(value, sink->device); break; */ case PROP_CARD: g_value_set_int (value, sink->card); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static gboolean alsaspdifsink_set_caps (GstBaseSink * bsink, GstCaps * caps) { AlsaSPDIFSink *sink = ALSASPDIFSINK (bsink); if (!gst_structure_get_int (gst_caps_get_structure (caps, 0), "rate", &sink->rate)) sink->rate = 48000; if (!alsaspdifsink_set_params (sink)) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Cannot set ALSA hardware parameters"), GST_ERROR_SYSTEM); return FALSE; } return TRUE; } static GstClock * alsaspdifsink_provide_clock (GstElement * elem) { AlsaSPDIFSink *sink = ALSASPDIFSINK (elem); return GST_CLOCK (gst_object_ref (sink->clock)); } static GstClockTime alsaspdifsink_get_time (GstClock * clock, gpointer user_data) { GstClockTime result; snd_pcm_sframes_t raw, delay, samples; AlsaSPDIFSink *sink = ALSASPDIFSINK (user_data); raw = samples = sink->frames * IEC958_SAMPLES_PER_FRAME; delay = alsaspdifsink_delay (sink); if (samples > delay) samples -= delay; else samples = 0; result = gst_util_uint64_scale_int (samples, GST_SECOND, sink->rate); GST_LOG_OBJECT (sink, "Samples raw: %d, delay: %d, real: %d, " "Time: %" GST_TIME_FORMAT, (int) raw, (int) delay, (int) samples, GST_TIME_ARGS (result)); return result; } static gboolean alsaspdifsink_open (AlsaSPDIFSink * sink) { char *pcm_name = sink->device; int err; char devstr[256]; /* Storage for local 'default' device string */ /* * Try and open our default iec958 device. Fall back to searching on card x * if this fails, which should only happen on older alsa setups */ /* The string will be one of these: * SPDIF_CON: Non-audio flag not set: * spdif:{AES0 0x0 AES1 0x82 AES2 0x0 AES3 0x2} * SPDIF_CON: Non-audio flag set: * spdif:{AES0 0x2 AES1 0x82 AES2 0x0 AES3 0x2} */ sprintf (devstr, "iec958:{CARD %d AES0 0x%02x AES1 0x%02x AES2 0x%02x AES3 0x%02x}", sink->card, IEC958_AES0_NONAUDIO, IEC958_AES1_CON_ORIGINAL | IEC958_AES1_CON_PCM_CODER, 0, IEC958_AES3_CON_FS_48000); GST_DEBUG_OBJECT (sink, "Generated device string \"%s\"", devstr); pcm_name = devstr; err = snd_pcm_open (&(sink->pcm), pcm_name, SND_PCM_STREAM_PLAYBACK, 0); if (err < 0) { GST_DEBUG_OBJECT (sink, "Open failed for %s - searching for IEC958 manually\n", pcm_name); err = alsaspdifsink_find_pcm_device (sink); if (err == 0 && sink->pcm == NULL) goto open_failed; } if (err < 0) goto failed; return TRUE; /* ERRORS */ open_failed: { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Could not open IEC958/SPDIF output device"), GST_ERROR_SYSTEM); return FALSE; } failed: { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("snd_pcm_open: %s", snd_strerror (err)), GST_ERROR_SYSTEM); return FALSE; } } static gboolean alsaspdifsink_set_params (AlsaSPDIFSink * sink) { snd_pcm_hw_params_t *params; unsigned int rate; int err; snd_pcm_hw_params_malloc (¶ms); err = snd_pcm_hw_params_any (sink->pcm, params); if (err < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Broken configuration for this PCM: " "no configurations available"), GST_ERROR_SYSTEM); goto __error; } /* Set interleaved access. */ err = snd_pcm_hw_params_set_access (sink->pcm, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (err < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Access type not available"), GST_ERROR_SYSTEM); goto __error; } err = snd_pcm_hw_params_set_format (sink->pcm, params, AC3_FORMAT_BE); if (err < 0) { /* Try LE output and swap data */ GST_DEBUG_OBJECT (sink, "PCM format S16_BE not supported, trying S16_LE"); err = snd_pcm_hw_params_set_format (sink->pcm, params, AC3_FORMAT_LE); sink->need_swap = TRUE; } else sink->need_swap = FALSE; if (err < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Sample format not available"), GST_ERROR_SYSTEM); goto __error; } err = snd_pcm_hw_params_set_channels (sink->pcm, params, AC3_CHANNELS); if (err < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Channels count not available"), GST_ERROR_SYSTEM); goto __error; } rate = sink->rate; GST_DEBUG_OBJECT (sink, "Setting S/PDIF sample rate: %d", rate); err = snd_pcm_hw_params_set_rate_near (sink->pcm, params, &rate, 0); if (err != 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("Rate not available"), GST_ERROR_SYSTEM); goto __error; } err = snd_pcm_hw_params (sink->pcm, params); if (err < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("PCM hw_params failed: %s", snd_strerror (err)), GST_ERROR_SYSTEM); goto __error; } snd_pcm_hw_params_free (params); return TRUE; /* ERRORS */ __error: { snd_pcm_hw_params_free (params); return FALSE; } } static void alsaspdifsink_close (AlsaSPDIFSink * sink) { if (sink->pcm) { snd_pcm_close (sink->pcm); sink->pcm = NULL; } } /* Try and find an IEC958 PCM device and mixer on card 0 and open it * This function is only used on older ALSA installs that don't have the * correct iec958 alias stuff set up, and relies on there being only * one IEC958 PCM device (relies IEC958 in the device name) and one IEC958 * mixer control for doing the settings. */ static int alsaspdifsink_find_pcm_device (AlsaSPDIFSink * sink) { int err = -1, dev, idx, count; const gchar *ctl_name = "hw:0"; const gchar *spdif_name = SND_CTL_NAME_IEC958 ("", PLAYBACK, NONE); int card = sink->card; gchar pcm_name[24]; snd_pcm_t *pcm = NULL; snd_ctl_t *ctl = NULL; snd_ctl_card_info_t *info = NULL; snd_ctl_elem_list_t *clist = NULL; snd_ctl_elem_id_t *cid = NULL; snd_pcm_info_t *pinfo = NULL; GST_WARNING ("Opening IEC958 named device failed. Trying to autodetect"); if ((err = snd_ctl_open (&ctl, ctl_name, card)) < 0) return err; snd_ctl_card_info_malloc (&info); snd_pcm_info_malloc (&pinfo); /* Find a mixer for IEC958 settings */ snd_ctl_elem_list_malloc (&clist); if ((err = snd_ctl_elem_list (ctl, clist)) < 0) goto beach; if ((err = snd_ctl_elem_list_alloc_space (clist, snd_ctl_elem_list_get_count (clist))) < 0) goto beach; if ((err = snd_ctl_elem_list (ctl, clist)) < 0) goto beach; count = snd_ctl_elem_list_get_used (clist); for (idx = 0; idx < count; idx++) { if (strstr (snd_ctl_elem_list_get_name (clist, idx), spdif_name) != NULL) break; } if (idx == count) { /* No SPDIF mixer availble */ err = 0; goto beach; } snd_ctl_elem_id_malloc (&cid); snd_ctl_elem_list_get_id (clist, idx, cid); /* Now find a PCM device for IEC 958 */ if ((err = snd_ctl_card_info (ctl, info)) < 0) goto beach; dev = -1; do { if (snd_ctl_pcm_next_device (ctl, &dev) < 0) goto beach; if (dev < 0) break; /* No more devices */ /* Filter for playback devices */ snd_pcm_info_set_device (pinfo, dev); snd_pcm_info_set_subdevice (pinfo, 0); snd_pcm_info_set_stream (pinfo, SND_PCM_STREAM_PLAYBACK); if ((err = snd_ctl_pcm_info (ctl, pinfo)) < 0) { if (err != -ENOENT) goto beach; /* Genuine error */ /* Device has no playback streams */ continue; } if (strstr (snd_pcm_info_get_name (pinfo), "IEC958") == NULL) continue; /* Not the device we are looking for */ count = snd_pcm_info_get_subdevices_count (pinfo); GST_LOG_OBJECT (sink, "Device %d has %d subdevices\n", dev, snd_pcm_info_get_subdevices_count (pinfo)); for (idx = 0; idx < count; idx++) { snd_pcm_info_set_subdevice (pinfo, idx); if ((err = snd_ctl_pcm_info (ctl, pinfo)) < 0) goto beach; g_assert (snd_pcm_info_get_stream (pinfo) == SND_PCM_STREAM_PLAYBACK); GST_LOG_OBJECT (sink, "Found playback stream on dev %d sub-d %d\n", dev, idx); /* Found a suitable PCM device, let's open it */ g_snprintf (pcm_name, 24, "hw:%d,%d", card, dev); if ((err = snd_pcm_open (&(pcm), pcm_name, SND_PCM_STREAM_PLAYBACK, 0)) < 0) goto beach; break; } } while (pcm == NULL); if (pcm != NULL) { snd_ctl_elem_value_t *cval; snd_aes_iec958_t iec958; /* Have a PCM device and a mixer, set things up */ snd_ctl_elem_value_malloc (&cval); snd_ctl_elem_value_set_id (cval, cid); snd_ctl_elem_value_get_iec958 (cval, &iec958); iec958.status[0] = IEC958_AES0_NONAUDIO; iec958.status[1] = IEC958_AES1_CON_ORIGINAL | IEC958_AES1_CON_PCM_CODER; iec958.status[2] = 0; iec958.status[3] = IEC958_AES3_CON_FS_48000; snd_ctl_elem_value_set_iec958 (cval, &iec958); snd_ctl_elem_value_free (cval); sink->pcm = pcm; pcm = NULL; err = 0; } beach: if (pcm) snd_pcm_close (pcm); if (clist) snd_ctl_elem_list_clear (clist); if (ctl) snd_ctl_close (ctl); if (clist) snd_ctl_elem_list_free (clist); if (cid) snd_ctl_elem_id_free (cid); if (info) snd_ctl_card_info_free (info); if (pinfo) snd_pcm_info_free (pinfo); return err; } static void alsaspdifsink_write_frame (AlsaSPDIFSink * sink, guchar * buf) { snd_pcm_sframes_t res; int num_frames = IEC958_FRAME_SIZE / ALSASPDIFSINK_BYTES_PER_FRAME; /* If we couldn't output big endian when we opened the devic, then * we need to swap here */ if (sink->need_swap) { int i; guchar tmp; for (i = 0; i < IEC958_FRAME_SIZE; i += 2) { tmp = buf[i]; buf[i] = buf[i + 1]; buf[i + 1] = tmp; } } res = 0; do { if (res == -EPIPE) { /* Underrun. */ GST_INFO_OBJECT (sink, "buffer underrun"); res = snd_pcm_prepare (sink->pcm); } else if (res == -ESTRPIPE) { /* Suspend. */ while ((res = snd_pcm_resume (sink->pcm)) == -EAGAIN) { GST_DEBUG_OBJECT (sink, "sleeping for suspend"); g_usleep (100000); } if (res < 0) { res = snd_pcm_prepare (sink->pcm); } } if (res >= 0) { res = snd_pcm_writei (sink->pcm, (void *) buf, num_frames); } if (res > 0) { num_frames -= res; } } while (res == -EPIPE || num_frames > 0); sink->frames++; if (res < 0) { GST_ELEMENT_ERROR (sink, RESOURCE, OPEN_WRITE, ("writei returned error: %s", snd_strerror (res)), GST_ERROR_SYSTEM); return; } } static gboolean alsaspdifsink_event (GstBaseSink * bsink, GstEvent * event) { AlsaSPDIFSink *sink = ALSASPDIFSINK (bsink); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_FLUSH_START: snd_pcm_drop (sink->pcm); break; case GST_EVENT_FLUSH_STOP: snd_pcm_start (sink->pcm); break; default: break; } return TRUE; } static void alsaspdifsink_get_times (GstBaseSink * bsink, GstBuffer * buffer, GstClockTime * start, GstClockTime * end) { /* Like GstBaseAudioSink, we set these to NONE */ *start = GST_CLOCK_TIME_NONE; *end = GST_CLOCK_TIME_NONE; } static snd_pcm_sframes_t alsaspdifsink_delay (AlsaSPDIFSink * sink) { snd_pcm_sframes_t delay; int err; err = snd_pcm_delay (sink->pcm, &delay); if (err < 0 || delay < 0) { return 0; } return delay; } #if 0 static void generate_iec958_zero_frame (guchar * buffer) { /* 2 sync words, 16 bits each */ buffer[0] = 0xF8; buffer[1] = 0x72; buffer[2] = 0x4E; buffer[3] = 0x1F; /* 16-bit burst-info. Contains data type (zero here, for 'null data'), stream number (we output '0' for this always), and a few other bits. As it happens, all-zero is the correct value. */ buffer[4] = 0; buffer[5] = 0; /* 16-bit frame size. Also zero */ buffer[6] = 0; buffer[7] = 0; memset (buffer + 8, 0, IEC958_FRAME_SIZE - 8); } #endif static GstFlowReturn alsaspdifsink_render (GstBaseSink * bsink, GstBuffer * buf) { AlsaSPDIFSink *sink = ALSASPDIFSINK (bsink); #if 0 GstClockTime next_write; if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buf))) sink->cur_ts = GST_BUFFER_TIMESTAMP (buf); next_write = gst_element_get_time (GST_ELEMENT (sink)) + alsaspdifsink_current_delay (sink); /* fprintf (stderr, "Drift: % 0.6fs, delay: % 0.6fs\r", GST_TIME_ARGS (GST_CLOCK_DIFF (sink->cur_ts, next_write)), GST_TIME_ARGS (alsaspdifsink_current_delay (sink))); */ /* If we're too far behind, send empty IEC958 frames. */ if (sink->cur_ts > next_write + MAX_SYNC_DIFF) { int frames = (int) ( ((double) (sink->cur_ts - next_write)) / (double) IEC958_FRAME_DURATION + 0.5); int i; for (i = 0; i < frames; i++) { static guchar frame[IEC958_FRAME_SIZE]; generate_iec958_zero_frame (frame); alsaspdifsink_write_frame (sink, frame); } } /* If we're too far ahead, just drop this buffer */ else if (sink->cur_ts + MAX_SYNC_DIFF < next_write) { goto end; } #endif GST_LOG_OBJECT (sink, "Writing %d bytes to spdif out", GST_BUFFER_SIZE (buf)); if (GST_BUFFER_SIZE (buf) == IEC958_FRAME_SIZE) alsaspdifsink_write_frame (sink, GST_BUFFER_DATA (buf)); else GST_WARNING_OBJECT (sink, "Ignoring buffer of incorrect size"); #if 0 end: if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buf))) sink->cur_ts = GST_BUFFER_DURATION (buf); #endif return GST_FLOW_OK; } /* Drop error output from within alsalib on the floor */ static void ignore_alsa_err (const char *file, int line, const char *function, int err, const char *fmt, ...) { } static GstStateChangeReturn alsaspdifsink_change_state (GstElement * element, GstStateChange transition) { AlsaSPDIFSink *sink = ALSASPDIFSINK (element); GstStateChangeReturn ret; switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: sink->frames = 0; gst_audio_clock_reset (GST_AUDIO_CLOCK (sink->clock), 0); break; case GST_STATE_CHANGE_READY_TO_PAUSED: if (!alsaspdifsink_open (sink)) { GST_WARNING_OBJECT (sink, "Failed to open alsa device"); return GST_STATE_CHANGE_FAILURE; } break; case GST_STATE_CHANGE_PAUSED_TO_PLAYING: break; default: break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); GST_INFO_OBJECT (sink, "Parent change_state returned %d", ret); switch (transition) { case GST_STATE_CHANGE_PLAYING_TO_PAUSED: break; case GST_STATE_CHANGE_PAUSED_TO_READY: break; case GST_STATE_CHANGE_READY_TO_NULL: alsaspdifsink_close (sink); break; default: break; } return ret; } static gboolean plugin_init (GstPlugin * plugin) { /* no rank so it doesn't get autoplugged by autoaudiosink */ if (!gst_element_register (plugin, "alsaspdifsink", GST_RANK_NONE, GST_TYPE_ALSASPDIFSINK)) { return FALSE; } return TRUE; } GST_PLUGIN_DEFINE (GST_VERSION_MAJOR, GST_VERSION_MINOR, "alsaspdif", "Alsa plugin for S/PDIF output", plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN);