/* * Copyright (C) 2008 Ole André Vadla Ravnås * * 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. */ /** * SECTION:element-ksvideosrc * * Provides low-latency video capture from WDM cameras on Windows. * * * Example pipelines * |[ * gst-launch -v ksvideosrc do-stats=TRUE ! ffmpegcolorspace ! dshowvideosink * ]| Capture from a camera and render using dshowvideosink. * |[ * gst-launch -v ksvideosrc do-stats=TRUE ! image/jpeg, width=640, height=480 * ! jpegdec ! ffmpegcolorspace ! dshowvideosink * ]| Capture from an MJPEG camera and render using dshowvideosink. * */ #include "gstksvideosrc.h" #ifdef HAVE_CONFIG_H # include #endif #include "gstksclock.h" #include "gstksvideodevice.h" #include "kshelpers.h" #include "ksvideohelpers.h" #define ENABLE_CLOCK_DEBUG 0 #define DEFAULT_DEVICE_PATH NULL #define DEFAULT_DEVICE_NAME NULL #define DEFAULT_DEVICE_INDEX -1 #define DEFAULT_ENSLAVE_KSCLOCK FALSE #define DEFAULT_DO_STATS FALSE enum { PROP_0, PROP_DEVICE_PATH, PROP_DEVICE_NAME, PROP_DEVICE_INDEX, PROP_ENSLAVE_KSCLOCK, PROP_DO_STATS, PROP_FPS, }; GST_DEBUG_CATEGORY (gst_ks_debug); #define GST_CAT_DEFAULT gst_ks_debug typedef struct { /* Properties */ gchar *device_path; gchar *device_name; gint device_index; gboolean enslave_ksclock; gboolean do_stats; /* State */ GstKsClock *ksclock; GstKsVideoDevice *device; guint64 offset; GstClockTime prev_ts; /* Statistics */ GstClockTime last_sampling; guint count; guint fps; } GstKsVideoSrcPrivate; #define GST_KS_VIDEO_SRC_GET_PRIVATE(o) \ (G_TYPE_INSTANCE_GET_PRIVATE ((o), GST_TYPE_KS_VIDEO_SRC, \ GstKsVideoSrcPrivate)) static void gst_ks_video_src_dispose (GObject * object); static void gst_ks_video_src_finalize (GObject * object); static void gst_ks_video_src_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_ks_video_src_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_ks_video_src_reset (GstKsVideoSrc * self); static GstStateChangeReturn gst_ks_video_src_change_state (GstElement * element, GstStateChange transition); static gboolean gst_ks_video_src_set_clock (GstElement * element, GstClock * clock); static GstCaps *gst_ks_video_src_get_caps (GstBaseSrc * basesrc); static gboolean gst_ks_video_src_set_caps (GstBaseSrc * basesrc, GstCaps * caps); static void gst_ks_video_src_fixate (GstBaseSrc * basesrc, GstCaps * caps); static gboolean gst_ks_video_src_query (GstBaseSrc * basesrc, GstQuery * query); static gboolean gst_ks_video_src_unlock (GstBaseSrc * basesrc); static gboolean gst_ks_video_src_unlock_stop (GstBaseSrc * basesrc); static GstFlowReturn gst_ks_video_src_create (GstPushSrc * pushsrc, GstBuffer ** buffer); GST_BOILERPLATE (GstKsVideoSrc, gst_ks_video_src, GstPushSrc, GST_TYPE_PUSH_SRC); static void gst_ks_video_src_base_init (gpointer gclass) { GstElementClass *element_class = GST_ELEMENT_CLASS (gclass); static GstElementDetails element_details = { "KsVideoSrc", "Source/Video", "Stream data from a video capture device through Windows kernel streaming", "Ole André Vadla Ravnås \n" "Haakon Sporsheim " }; gst_element_class_set_details (element_class, &element_details); gst_element_class_add_pad_template (element_class, gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS, ks_video_get_all_caps ())); } static void gst_ks_video_src_class_init (GstKsVideoSrcClass * klass) { GObjectClass *gobject_class = G_OBJECT_CLASS (klass); GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass); GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass); GstPushSrcClass *gstpushsrc_class = GST_PUSH_SRC_CLASS (klass); g_type_class_add_private (klass, sizeof (GstKsVideoSrcPrivate)); gobject_class->dispose = gst_ks_video_src_dispose; gobject_class->finalize = gst_ks_video_src_finalize; gobject_class->get_property = gst_ks_video_src_get_property; gobject_class->set_property = gst_ks_video_src_set_property; gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_ks_video_src_change_state); gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_ks_video_src_set_clock); gstbasesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_ks_video_src_get_caps); gstbasesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_ks_video_src_set_caps); gstbasesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_ks_video_src_fixate); gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_ks_video_src_query); gstbasesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_ks_video_src_unlock); gstbasesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_ks_video_src_unlock_stop); gstpushsrc_class->create = GST_DEBUG_FUNCPTR (gst_ks_video_src_create); g_object_class_install_property (gobject_class, PROP_DEVICE_PATH, g_param_spec_string ("device-path", "Device Path", "The device path", DEFAULT_DEVICE_PATH, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_DEVICE_NAME, g_param_spec_string ("device-name", "Device Name", "The human-readable device name", DEFAULT_DEVICE_NAME, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_DEVICE_INDEX, g_param_spec_int ("device-index", "Device Index", "The zero-based device index", -1, G_MAXINT, DEFAULT_DEVICE_INDEX, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_ENSLAVE_KSCLOCK, g_param_spec_boolean ("enslave-ksclock", "Enslave the clock used by KS", "Enslave the clocked used by Kernel Streaming", DEFAULT_ENSLAVE_KSCLOCK, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_DO_STATS, g_param_spec_boolean ("do-stats", "Enable statistics", "Enable logging of statistics", DEFAULT_DO_STATS, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, PROP_FPS, g_param_spec_int ("fps", "Frames per second", "Last measured framerate, if statistics are enabled", -1, G_MAXINT, -1, G_PARAM_READABLE)); GST_DEBUG_CATEGORY_INIT (gst_ks_debug, "ksvideosrc", 0, "Kernel streaming video source"); } static void gst_ks_video_src_init (GstKsVideoSrc * self, GstKsVideoSrcClass * gclass) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GstBaseSrc *basesrc = GST_BASE_SRC (self); gst_base_src_set_live (basesrc, TRUE); gst_base_src_set_format (basesrc, GST_FORMAT_TIME); gst_ks_video_src_reset (self); priv->device_path = DEFAULT_DEVICE_PATH; priv->device_name = DEFAULT_DEVICE_NAME; priv->device_index = DEFAULT_DEVICE_INDEX; priv->enslave_ksclock = DEFAULT_ENSLAVE_KSCLOCK; priv->do_stats = DEFAULT_DO_STATS; } static void gst_ks_video_src_dispose (GObject * object) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (object); G_OBJECT_CLASS (parent_class)->dispose (object); } static void gst_ks_video_src_finalize (GObject * object) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (object); G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_ks_video_src_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (object); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); switch (prop_id) { case PROP_DEVICE_PATH: g_value_set_string (value, priv->device_path); break; case PROP_DEVICE_NAME: g_value_set_string (value, priv->device_name); break; case PROP_DEVICE_INDEX: g_value_set_int (value, priv->device_index); break; case PROP_ENSLAVE_KSCLOCK: g_value_set_boolean (value, priv->enslave_ksclock); break; case PROP_DO_STATS: GST_OBJECT_LOCK (object); g_value_set_boolean (value, priv->do_stats); GST_OBJECT_UNLOCK (object); break; case PROP_FPS: GST_OBJECT_LOCK (object); g_value_set_int (value, priv->fps); GST_OBJECT_UNLOCK (object); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_ks_video_src_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (object); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); switch (prop_id) { case PROP_DEVICE_PATH: g_free (priv->device_path); priv->device_path = g_value_dup_string (value); break; case PROP_DEVICE_NAME: g_free (priv->device_name); priv->device_name = g_value_dup_string (value); break; case PROP_DEVICE_INDEX: priv->device_index = g_value_get_int (value); break; case PROP_ENSLAVE_KSCLOCK: GST_OBJECT_LOCK (object); if (priv->device == NULL) priv->enslave_ksclock = g_value_get_boolean (value); else g_warning ("enslave-ksclock may only be changed while in NULL state"); GST_OBJECT_UNLOCK (object); break; case PROP_DO_STATS: GST_OBJECT_LOCK (object); priv->do_stats = g_value_get_boolean (value); GST_OBJECT_UNLOCK (object); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_ks_video_src_reset (GstKsVideoSrc * self) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); /* Reset statistics */ priv->last_sampling = GST_CLOCK_TIME_NONE; priv->count = 0; priv->fps = -1; /* Reset timestamping state */ priv->offset = 0; priv->prev_ts = GST_CLOCK_TIME_NONE; } static gboolean gst_ks_video_src_open_device (GstKsVideoSrc * self) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GstKsVideoDevice *device = NULL; GList *devices, *cur; g_assert (priv->device == NULL); devices = ks_enumerate_devices (&KSCATEGORY_VIDEO); if (devices == NULL) goto error_no_devices; for (cur = devices; cur != NULL; cur = cur->next) { KsDeviceEntry *entry = cur->data; GST_DEBUG_OBJECT (self, "device %d: name='%s' path='%s'", entry->index, entry->name, entry->path); } for (cur = devices; cur != NULL && device == NULL; cur = cur->next) { KsDeviceEntry *entry = cur->data; gboolean match; if (priv->device_path != NULL) { match = g_strcasecmp (entry->path, priv->device_path) == 0; } else if (priv->device_name != NULL) { match = g_strcasecmp (entry->name, priv->device_name) == 0; } else if (priv->device_index >= 0) { match = entry->index == priv->device_index; } else { match = TRUE; /* pick the first entry */ } if (match) { priv->ksclock = NULL; if (priv->enslave_ksclock) { priv->ksclock = g_object_new (GST_TYPE_KS_CLOCK, NULL); if (priv->ksclock != NULL && !gst_ks_clock_open (priv->ksclock)) { g_object_unref (priv->ksclock); priv->ksclock = NULL; } if (priv->ksclock == NULL) GST_WARNING_OBJECT (self, "Failed to create/open KsClock"); } device = g_object_new (GST_TYPE_KS_VIDEO_DEVICE, "clock", priv->ksclock, "device-path", entry->path, NULL); } ks_device_entry_free (entry); } g_list_free (devices); if (device == NULL) goto error_no_match; if (!gst_ks_video_device_open (device)) goto error_open; priv->device = device; return TRUE; /* ERRORS */ error_no_devices: { GST_ELEMENT_ERROR (self, RESOURCE, NOT_FOUND, ("No video capture devices found"), (NULL)); return FALSE; } error_no_match: { if (priv->device_path != NULL) { GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS, ("Specified video capture device with path '%s' not found", priv->device_path), (NULL)); } else if (priv->device_name != NULL) { GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS, ("Specified video capture device with name '%s' not found", priv->device_name), (NULL)); } else { GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS, ("Specified video capture device with index %d not found", priv->device_index), (NULL)); } return FALSE; } error_open: { GST_ELEMENT_ERROR (self, RESOURCE, OPEN_READ, ("Failed to open device"), (NULL)); g_object_unref (device); return FALSE; } } static void gst_ks_video_src_close_device (GstKsVideoSrc * self) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); g_assert (priv->device != NULL); gst_ks_video_device_close (priv->device); g_object_unref (priv->device); priv->device = NULL; if (priv->ksclock != NULL) { gst_ks_clock_close (priv->ksclock); g_object_unref (priv->ksclock); priv->ksclock = NULL; } gst_ks_video_src_reset (self); } static GstStateChangeReturn gst_ks_video_src_change_state (GstElement * element, GstStateChange transition) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (element); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GstStateChangeReturn ret; switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: if (!gst_ks_video_src_open_device (self)) goto open_failed; break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); switch (transition) { case GST_STATE_CHANGE_READY_TO_NULL: gst_ks_video_src_close_device (self); break; } return ret; /* ERRORS */ open_failed: { return GST_STATE_CHANGE_FAILURE; } } static gboolean gst_ks_video_src_set_clock (GstElement * element, GstClock * clock) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (element); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GST_OBJECT_LOCK (element); if (priv->ksclock != NULL) gst_ks_clock_provide_master_clock (priv->ksclock, clock); GST_OBJECT_UNLOCK (element); return TRUE; } static GstCaps * gst_ks_video_src_get_caps (GstBaseSrc * basesrc) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (basesrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); if (priv->device != NULL) return gst_ks_video_device_get_available_caps (priv->device); else return NULL; /* BaseSrc will return template caps */ } static gboolean gst_ks_video_src_set_caps (GstBaseSrc * basesrc, GstCaps * caps) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (basesrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); if (priv->device == NULL) return FALSE; if (!gst_ks_video_device_set_caps (priv->device, caps)) return FALSE; if (!gst_ks_video_device_set_state (priv->device, KSSTATE_PAUSE)) return FALSE; return TRUE; } static void gst_ks_video_src_fixate (GstBaseSrc * basesrc, GstCaps * caps) { GstStructure *structure = gst_caps_get_structure (caps, 0); gst_structure_fixate_field_nearest_int (structure, "width", G_MAXINT); gst_structure_fixate_field_nearest_int (structure, "height", G_MAXINT); gst_structure_fixate_field_nearest_fraction (structure, "framerate", G_MAXINT, 1); } static gboolean gst_ks_video_src_query (GstBaseSrc * basesrc, GstQuery * query) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (basesrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); gboolean result = FALSE; switch (GST_QUERY_TYPE (query)) { case GST_QUERY_LATENCY:{ GstClockTime min_latency, max_latency; if (priv->device == NULL) goto beach; result = gst_ks_video_device_get_latency (priv->device, &min_latency, &max_latency); if (!result) goto beach; GST_DEBUG_OBJECT (self, "reporting latency of min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT, GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency)); gst_query_set_latency (query, TRUE, min_latency, max_latency); break; } default: result = GST_BASE_SRC_CLASS (parent_class)->query (basesrc, query); break; } beach: return result; } static gboolean gst_ks_video_src_unlock (GstBaseSrc * basesrc) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (basesrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GST_DEBUG_OBJECT (self, "%s", G_STRFUNC); gst_ks_video_device_cancel (priv->device); return TRUE; } static gboolean gst_ks_video_src_unlock_stop (GstBaseSrc * basesrc) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (basesrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GST_DEBUG_OBJECT (self, "%s", G_STRFUNC); gst_ks_video_device_cancel_stop (priv->device); return TRUE; } static gboolean gst_ks_video_src_timestamp_buffer (GstKsVideoSrc * self, GstBuffer * buf, GstClockTime presentation_time) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GstClockTime duration; GstClock *clock; GstClockTime timestamp; duration = gst_ks_video_device_get_duration (priv->device); GST_OBJECT_LOCK (self); clock = GST_ELEMENT_CLOCK (self); if (clock != NULL) { gst_object_ref (clock); timestamp = GST_ELEMENT (self)->base_time; if (GST_CLOCK_TIME_IS_VALID (presentation_time)) { if (presentation_time > GST_ELEMENT (self)->base_time) presentation_time -= GST_ELEMENT (self)->base_time; else presentation_time = 0; } } else { timestamp = GST_CLOCK_TIME_NONE; } GST_OBJECT_UNLOCK (self); if (clock != NULL) { /* The time according to the current clock */ timestamp = gst_clock_get_time (clock) - timestamp; if (timestamp > duration) timestamp -= duration; else timestamp = 0; if (GST_CLOCK_TIME_IS_VALID (presentation_time)) { GstClockTimeDiff diff = GST_CLOCK_DIFF (timestamp, presentation_time); GST_DEBUG_OBJECT (self, "Diff between our and the driver's timestamp: %" G_GINT64_FORMAT, diff); } gst_object_unref (clock); clock = NULL; /* Unless it's the first frame, align the current timestamp on a multiple * of duration since the previous */ if (GST_CLOCK_TIME_IS_VALID (priv->prev_ts)) { GstClockTime delta; guint delta_remainder, delta_offset; /* REVISIT: I've seen this happen with the GstSystemClock on Windows, * scary... */ if (timestamp < priv->prev_ts) { GST_WARNING_OBJECT (self, "clock is ticking backwards"); return FALSE; } /* Round to a duration boundary */ delta = timestamp - priv->prev_ts; delta_remainder = delta % duration; if (delta_remainder < duration / 3) timestamp -= delta_remainder; else timestamp += duration - delta_remainder; /* How many frames are we off then? */ delta = timestamp - priv->prev_ts; delta_offset = delta / duration; if (delta_offset == 1) /* perfect */ GST_BUFFER_FLAG_UNSET (buf, GST_BUFFER_FLAG_DISCONT); else if (delta_offset > 1) { guint lost = delta_offset - 1; #if ENABLE_CLOCK_DEBUG GST_INFO_OBJECT (self, "lost %d frame%s, setting discont flag", lost, (lost > 1) ? "s" : ""); #endif GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT); } else if (delta_offset == 0) { /* overproduction, skip this frame */ #if ENABLE_CLOCK_DEBUG GST_INFO_OBJECT (self, "skipping frame"); #endif return FALSE; } priv->offset += delta_offset; } priv->prev_ts = timestamp; } GST_BUFFER_OFFSET (buf) = priv->offset; GST_BUFFER_OFFSET_END (buf) = GST_BUFFER_OFFSET (buf) + 1; GST_BUFFER_TIMESTAMP (buf) = timestamp; GST_BUFFER_DURATION (buf) = duration; return TRUE; } static void gst_ks_video_src_update_statistics (GstKsVideoSrc * self) { GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); GstClock *clock; GST_OBJECT_LOCK (self); clock = GST_ELEMENT_CLOCK (self); if (clock != NULL) gst_object_ref (clock); GST_OBJECT_UNLOCK (self); if (clock != NULL) { GstClockTime now = gst_clock_get_time (clock); gst_object_unref (clock); priv->count++; if (GST_CLOCK_TIME_IS_VALID (priv->last_sampling)) { if (now - priv->last_sampling >= GST_SECOND) { GST_OBJECT_LOCK (self); priv->fps = priv->count; GST_OBJECT_UNLOCK (self); g_object_notify (G_OBJECT (self), "fps"); priv->last_sampling = now; priv->count = 0; } } else { priv->last_sampling = now; } } } static GstFlowReturn gst_ks_video_src_create (GstPushSrc * pushsrc, GstBuffer ** buffer) { GstKsVideoSrc *self = GST_KS_VIDEO_SRC (pushsrc); GstKsVideoSrcPrivate *priv = GST_KS_VIDEO_SRC_GET_PRIVATE (self); guint buf_size; GstCaps *caps; GstBuffer *buf = NULL; GstFlowReturn result; GstClockTime presentation_time; gulong error_code; gchar *error_str; g_assert (priv->device != NULL); if (!gst_ks_video_device_has_caps (priv->device)) goto error_no_caps; buf_size = gst_ks_video_device_get_frame_size (priv->device); g_assert (buf_size); caps = gst_pad_get_negotiated_caps (GST_BASE_SRC_PAD (self)); if (caps == NULL) goto error_no_caps; result = gst_pad_alloc_buffer (GST_BASE_SRC_PAD (self), priv->offset, buf_size, caps, &buf); gst_caps_unref (caps); if (G_UNLIKELY (result != GST_FLOW_OK)) goto error_alloc_buffer; do { gulong bytes_read; result = gst_ks_video_device_read_frame (priv->device, GST_BUFFER_DATA (buf), buf_size, &bytes_read, &presentation_time, &error_code, &error_str); if (G_UNLIKELY (result != GST_FLOW_OK)) goto error_read_frame; GST_BUFFER_SIZE (buf) = bytes_read; } while (!gst_ks_video_src_timestamp_buffer (self, buf, presentation_time)); if (G_UNLIKELY (priv->do_stats)) gst_ks_video_src_update_statistics (self); gst_ks_video_device_postprocess_frame (priv->device, GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf)); *buffer = buf; return GST_FLOW_OK; /* ERRORS */ error_no_caps: { GST_ELEMENT_ERROR (self, CORE, NEGOTIATION, ("not negotiated"), ("maybe setcaps failed?")); return GST_FLOW_ERROR; } error_alloc_buffer: { GST_ELEMENT_ERROR (self, CORE, PAD, ("alloc_buffer failed"), (NULL)); return result; } error_read_frame: { if (result != GST_FLOW_WRONG_STATE && result != GST_FLOW_UNEXPECTED) { GST_ELEMENT_ERROR (self, RESOURCE, READ, ("read failed: %s [0x%08x]", error_str, error_code), ("gst_ks_video_device_read_frame failed")); } g_free (error_str); gst_buffer_unref (buf); return result; } } static gboolean plugin_init (GstPlugin * plugin) { return gst_element_register (plugin, "ksvideosrc", GST_RANK_NONE, GST_TYPE_KS_VIDEO_SRC); } GST_PLUGIN_DEFINE (GST_VERSION_MAJOR, GST_VERSION_MINOR, "winks", "Windows kernel streaming plugin", plugin_init, VERSION, "LGPL", "GStreamer", "http://gstreamer.net/")