/* GStreamer * * uvch264_mjpg_demux: a demuxer for muxed stream in UVC H264 compliant MJPG * * Copyright (C) 2012 Cisco Systems, Inc. * Author: Youness Alaoui * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ /** * SECTION:element-uvch264mjpgdemux * @title: uvch264mjpgdemux * @short_description: UVC H264 compliant MJPG demuxer * * Parses a MJPG stream from a UVC H264 compliant encoding camera and extracts * each muxed stream into separate pads. * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #ifndef UVCIOC_GET_LAST_SCR #include struct uvc_last_scr_sample { __u32 dev_frequency; __u32 dev_stc; __u16 dev_sof; struct timespec host_ts; __u16 host_sof; }; #define UVCIOC_GET_LAST_SCR _IOR('u', 0x23, struct uvc_last_scr_sample) #endif #include "gstuvch264_mjpgdemux.h" enum { PROP_0, PROP_DEVICE_FD, PROP_NUM_CLOCK_SAMPLES }; #define DEFAULT_NUM_CLOCK_SAMPLES 32 static GstStaticPadTemplate mjpgsink_pad_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("image/jpeg, " "width = (int) [ 0, MAX ]," "height = (int) [ 0, MAX ], " "framerate = (fraction) [ 0/1, MAX ] ") ); static GstStaticPadTemplate jpegsrc_pad_template = GST_STATIC_PAD_TEMPLATE ("jpeg", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("image/jpeg, " "width = (int) [ 0, MAX ]," "height = (int) [ 0, MAX ], " "framerate = (fraction) [ 0/1, MAX ] ") ); static GstStaticPadTemplate h264src_pad_template = GST_STATIC_PAD_TEMPLATE ("h264", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-h264, " "width = (int) [ 0, MAX ], " "height = (int) [ 0, MAX ], " "framerate = (fraction) [ 0/1, MAX ] ") ); static GstStaticPadTemplate yuy2src_pad_template = GST_STATIC_PAD_TEMPLATE ("yuy2", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-raw, " "format = (string) YUY2, " "width = (int) [ 0, MAX ], " "height = (int) [ 0, MAX ], " "framerate = (fraction) [ 0/1, MAX ] ") ); static GstStaticPadTemplate nv12src_pad_template = GST_STATIC_PAD_TEMPLATE ("nv12", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-raw, " "format = (string) NV12, " "width = (int) [ 0, MAX ], " "height = (int) [ 0, MAX ], " "framerate = (fraction) [ 0/1, MAX ] ") ); GST_DEBUG_CATEGORY_STATIC (uvc_h264_mjpg_demux_debug); #define GST_CAT_DEFAULT uvc_h264_mjpg_demux_debug typedef struct { guint32 dev_stc; guint32 dev_sof; GstClockTime host_ts; guint32 host_sof; } GstUvcH264ClockSample; struct _GstUvcH264MjpgDemuxPrivate { int device_fd; int num_clock_samples; GstUvcH264ClockSample *clock_samples; int last_sample; int num_samples; GstPad *sink_pad; GstPad *jpeg_pad; GstPad *h264_pad; GstPad *yuy2_pad; GstPad *nv12_pad; GstCaps *h264_caps; GstCaps *yuy2_caps; GstCaps *nv12_caps; guint16 h264_width; guint16 h264_height; guint16 yuy2_width; guint16 yuy2_height; guint16 nv12_width; guint16 nv12_height; /* input segment */ GstSegment segment; }; typedef struct { guint16 version; guint16 header_len; guint32 type; guint16 width; guint16 height; guint32 frame_interval; guint16 delay; guint32 pts; } __attribute__ ((packed)) AuxiliaryStreamHeader; static void gst_uvc_h264_mjpg_demux_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_uvc_h264_mjpg_demux_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_uvc_h264_mjpg_demux_dispose (GObject * object); static GstFlowReturn gst_uvc_h264_mjpg_demux_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer); static gboolean gst_uvc_h264_mjpg_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event); static gboolean gst_uvc_h264_mjpg_demux_query (GstPad * pad, GstObject * parent, GstQuery * query); #define gst_uvc_h264_mjpg_demux_parent_class parent_class G_DEFINE_TYPE (GstUvcH264MjpgDemux, gst_uvc_h264_mjpg_demux, GST_TYPE_ELEMENT); static void gst_uvc_h264_mjpg_demux_class_init (GstUvcH264MjpgDemuxClass * klass) { GObjectClass *gobject_class = (GObjectClass *) klass; GstElementClass *element_class = (GstElementClass *) klass; parent_class = g_type_class_peek_parent (klass); g_type_class_add_private (gobject_class, sizeof (GstUvcH264MjpgDemuxPrivate)); gobject_class->set_property = gst_uvc_h264_mjpg_demux_set_property; gobject_class->get_property = gst_uvc_h264_mjpg_demux_get_property; gobject_class->dispose = gst_uvc_h264_mjpg_demux_dispose; gst_element_class_add_static_pad_template (element_class, &mjpgsink_pad_template); gst_element_class_add_static_pad_template (element_class, &jpegsrc_pad_template); gst_element_class_add_static_pad_template (element_class, &h264src_pad_template); gst_element_class_add_static_pad_template (element_class, &yuy2src_pad_template); gst_element_class_add_static_pad_template (element_class, &nv12src_pad_template); gst_element_class_set_static_metadata (element_class, "UVC H264 MJPG Demuxer", "Video/Demuxer", "Demux UVC H264 auxiliary streams from MJPG images", "Youness Alaoui "); g_object_class_install_property (gobject_class, PROP_DEVICE_FD, g_param_spec_int ("device-fd", "device-fd", "File descriptor of the v4l2 device", -1, G_MAXINT, -1, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (gobject_class, PROP_NUM_CLOCK_SAMPLES, g_param_spec_int ("num-clock-samples", "num-clock-samples", "Number of clock samples to gather for the PTS synchronization" " (-1 = unlimited)", 0, G_MAXINT, DEFAULT_NUM_CLOCK_SAMPLES, G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS)); GST_DEBUG_CATEGORY_INIT (uvc_h264_mjpg_demux_debug, "uvch264mjpgdemux", 0, "UVC H264 MJPG Demuxer"); } static void gst_uvc_h264_mjpg_demux_init (GstUvcH264MjpgDemux * self) { self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, GST_TYPE_UVC_H264_MJPG_DEMUX, GstUvcH264MjpgDemuxPrivate); self->priv->device_fd = -1; /* create the sink and src pads */ self->priv->sink_pad = gst_pad_new_from_static_template (&mjpgsink_pad_template, "sink"); gst_pad_set_chain_function (self->priv->sink_pad, GST_DEBUG_FUNCPTR (gst_uvc_h264_mjpg_demux_chain)); gst_pad_set_event_function (self->priv->sink_pad, GST_DEBUG_FUNCPTR (gst_uvc_h264_mjpg_demux_sink_event)); gst_pad_set_query_function (self->priv->sink_pad, GST_DEBUG_FUNCPTR (gst_uvc_h264_mjpg_demux_query)); gst_element_add_pad (GST_ELEMENT (self), self->priv->sink_pad); /* JPEG */ self->priv->jpeg_pad = gst_pad_new_from_static_template (&jpegsrc_pad_template, "jpeg"); gst_pad_set_query_function (self->priv->jpeg_pad, GST_DEBUG_FUNCPTR (gst_uvc_h264_mjpg_demux_query)); gst_element_add_pad (GST_ELEMENT (self), self->priv->jpeg_pad); /* H264 */ self->priv->h264_pad = gst_pad_new_from_static_template (&h264src_pad_template, "h264"); gst_pad_use_fixed_caps (self->priv->h264_pad); gst_element_add_pad (GST_ELEMENT (self), self->priv->h264_pad); /* YUY2 */ self->priv->yuy2_pad = gst_pad_new_from_static_template (&yuy2src_pad_template, "yuy2"); gst_pad_use_fixed_caps (self->priv->yuy2_pad); gst_element_add_pad (GST_ELEMENT (self), self->priv->yuy2_pad); /* NV12 */ self->priv->nv12_pad = gst_pad_new_from_static_template (&nv12src_pad_template, "nv12"); gst_pad_use_fixed_caps (self->priv->nv12_pad); gst_element_add_pad (GST_ELEMENT (self), self->priv->nv12_pad); self->priv->h264_caps = gst_caps_new_empty_simple ("video/x-h264"); self->priv->yuy2_caps = gst_caps_new_simple ("video/x-raw", "format", G_TYPE_STRING, "YUY2", NULL); self->priv->nv12_caps = gst_caps_new_simple ("video/x-raw", "format", G_TYPE_STRING, "NV12", NULL); self->priv->h264_width = self->priv->h264_height = 0; self->priv->yuy2_width = self->priv->yuy2_height = 0; self->priv->nv12_width = self->priv->nv12_height = 0; } static void gst_uvc_h264_mjpg_demux_dispose (GObject * object) { GstUvcH264MjpgDemux *self = GST_UVC_H264_MJPG_DEMUX (object); if (self->priv->h264_caps) gst_caps_unref (self->priv->h264_caps); self->priv->h264_caps = NULL; if (self->priv->yuy2_caps) gst_caps_unref (self->priv->yuy2_caps); self->priv->yuy2_caps = NULL; if (self->priv->nv12_caps) gst_caps_unref (self->priv->nv12_caps); self->priv->nv12_caps = NULL; g_free (self->priv->clock_samples); self->priv->clock_samples = NULL; G_OBJECT_CLASS (parent_class)->dispose (object); } static void gst_uvc_h264_mjpg_demux_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstUvcH264MjpgDemux *self = GST_UVC_H264_MJPG_DEMUX (object); switch (prop_id) { case PROP_DEVICE_FD: self->priv->device_fd = g_value_get_int (value); break; case PROP_NUM_CLOCK_SAMPLES: self->priv->num_clock_samples = g_value_get_int (value); if (self->priv->clock_samples) { if (self->priv->num_clock_samples) { self->priv->clock_samples = g_realloc_n (self->priv->clock_samples, self->priv->num_clock_samples, sizeof (GstUvcH264ClockSample)); if (self->priv->num_samples > self->priv->num_clock_samples) { self->priv->num_samples = self->priv->num_clock_samples; if (self->priv->last_sample >= self->priv->num_samples) self->priv->last_sample = self->priv->num_samples - 1; } } else { g_free (self->priv->clock_samples); self->priv->clock_samples = NULL; self->priv->last_sample = -1; self->priv->num_samples = 0; } } if (self->priv->num_clock_samples > 0) { self->priv->clock_samples = g_malloc0_n (self->priv->num_clock_samples, sizeof (GstUvcH264ClockSample)); self->priv->last_sample = -1; self->priv->num_samples = 0; } break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec); break; } } static void gst_uvc_h264_mjpg_demux_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstUvcH264MjpgDemux *self = GST_UVC_H264_MJPG_DEMUX (object); switch (prop_id) { case PROP_DEVICE_FD: g_value_set_int (value, self->priv->device_fd); break; case PROP_NUM_CLOCK_SAMPLES: g_value_set_int (value, self->priv->num_clock_samples); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec); break; } } static gboolean gst_uvc_h264_mjpg_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event) { GstUvcH264MjpgDemux *self = GST_UVC_H264_MJPG_DEMUX (parent); gboolean res; switch (GST_EVENT_TYPE (event)) { case GST_EVENT_SEGMENT: gst_event_copy_segment (event, &self->priv->segment); res = gst_pad_push_event (self->priv->jpeg_pad, event); break; case GST_EVENT_CAPS: res = gst_pad_push_event (self->priv->jpeg_pad, event); break; default: res = gst_pad_event_default (pad, parent, event); break; } return res; } static gboolean gst_uvc_h264_mjpg_demux_query (GstPad * pad, GstObject * parent, GstQuery * query) { GstUvcH264MjpgDemux *self = GST_UVC_H264_MJPG_DEMUX (parent); gboolean ret = FALSE; switch (GST_QUERY_TYPE (query)) { case GST_QUERY_CAPS: if (pad == self->priv->sink_pad) ret = gst_pad_peer_query (self->priv->jpeg_pad, query); else ret = gst_pad_peer_query (self->priv->sink_pad, query); break; default: ret = gst_pad_query_default (pad, parent, query); } return ret; } static gboolean _pts_to_timestamp (GstUvcH264MjpgDemux * self, GstBuffer * buf, guint32 pts) { GstUvcH264MjpgDemuxPrivate *priv = self->priv; GstUvcH264ClockSample *current_sample = NULL; GstUvcH264ClockSample *oldest_sample = NULL; guint32 next_sample; struct uvc_last_scr_sample sample; guint32 dev_sof; if (self->priv->device_fd == -1 || priv->clock_samples == NULL) return FALSE; if (-1 == ioctl (priv->device_fd, UVCIOC_GET_LAST_SCR, &sample)) { //GST_WARNING_OBJECT (self, " GET_LAST_SCR error"); return FALSE; } dev_sof = (guint32) (sample.dev_sof + 2048) << 16; if (priv->num_samples > 0 && priv->clock_samples[priv->last_sample].dev_sof == dev_sof) { current_sample = &priv->clock_samples[priv->last_sample]; } else { next_sample = (priv->last_sample + 1) % priv->num_clock_samples; current_sample = &priv->clock_samples[next_sample]; current_sample->dev_stc = sample.dev_stc; current_sample->dev_sof = dev_sof; current_sample->host_ts = sample.host_ts.tv_sec * GST_SECOND + sample.host_ts.tv_nsec * GST_NSECOND; current_sample->host_sof = (guint32) (sample.host_sof + 2048) << 16; priv->num_samples++; priv->last_sample = next_sample; /* Debug printing */ GST_DEBUG_OBJECT (self, "device frequency: %u", sample.dev_frequency); GST_DEBUG_OBJECT (self, "dev_sof: %u", sample.dev_sof); GST_DEBUG_OBJECT (self, "dev_stc: %u", sample.dev_stc); GST_DEBUG_OBJECT (self, "host_ts: %" G_GUINT64_FORMAT " -- %" GST_TIME_FORMAT, current_sample->host_ts, GST_TIME_ARGS (current_sample->host_ts)); GST_DEBUG_OBJECT (self, "host_sof: %u", sample.host_sof); GST_DEBUG_OBJECT (self, "PTS: %u", pts); GST_DEBUG_OBJECT (self, "Diff: %u - %f\n", sample.dev_stc - pts, (gdouble) (sample.dev_stc - pts) / sample.dev_frequency); } if (priv->num_samples < priv->num_clock_samples) return FALSE; next_sample = (priv->last_sample + 1) % priv->num_clock_samples; oldest_sample = &priv->clock_samples[next_sample]; /* TODO: Use current_sample and oldest_sample to do the * double linear regression and calculate a new PTS */ (void) oldest_sample; return TRUE; } static GstFlowReturn gst_uvc_h264_mjpg_demux_chain (GstPad * pad, GstObject * parent, GstBuffer * buf) { GstUvcH264MjpgDemux *self; GstFlowReturn ret = GST_FLOW_OK; GstBuffer *jpeg_buf = NULL; GstBuffer *aux_buf = NULL; AuxiliaryStreamHeader aux_header = { 0 }; guint32 aux_size = 0; GstPad *aux_pad = NULL; GstCaps **aux_caps = NULL; guint last_offset; guint i; GstMapInfo info; guint16 segment_size; self = GST_UVC_H264_MJPG_DEMUX (GST_PAD_PARENT (pad)); if (gst_buffer_get_size (buf) == 0) { return gst_pad_push (self->priv->jpeg_pad, buf); } last_offset = 0; gst_buffer_map (buf, &info, GST_MAP_READ); jpeg_buf = gst_buffer_copy_region (buf, GST_BUFFER_COPY_METADATA, 0, 0); for (i = 0; i < info.size - 1; i++) { /* Check for APP4 (0xe4) marker in the jpeg */ if (info.data[i] == 0xff && info.data[i + 1] == 0xe4) { /* Sanity check sizes and get segment size */ if (i + 4 >= info.size) { GST_ELEMENT_ERROR (self, STREAM, DEMUX, ("Not enough data to read marker size"), (NULL)); ret = GST_FLOW_ERROR; goto done; } segment_size = GUINT16_FROM_BE (*((guint16 *) (info.data + i + 2))); if (i + segment_size + 2 >= info.size) { GST_ELEMENT_ERROR (self, STREAM, DEMUX, ("Not enough data to read marker content"), (NULL)); ret = GST_FLOW_ERROR; goto done; } GST_DEBUG_OBJECT (self, "Found APP4 marker (%d). JPG: %d-%d - APP4: %d - %d", segment_size, last_offset, i, i, i + 2 + segment_size); /* Add JPEG data between the last offset and this market */ if (i - last_offset > 0) { GstMemory *m = gst_memory_copy (info.memory, last_offset, i - last_offset); gst_buffer_append_memory (jpeg_buf, m); } last_offset = i + 2 + segment_size; /* Reset i/segment size to the app4 data (ignore marker header/size) */ i += 4; segment_size -= 2; /* If this is a new auxiliary stream, initialize everything properly */ if (aux_buf == NULL) { if (segment_size < sizeof (aux_header) + sizeof (aux_size)) { GST_ELEMENT_ERROR (self, STREAM, DEMUX, ("Not enough data to read aux header"), (NULL)); ret = GST_FLOW_ERROR; goto done; } aux_header = *((AuxiliaryStreamHeader *) (info.data + i)); /* version should be little endian but it looks more like BE */ aux_header.version = GUINT16_FROM_BE (aux_header.version); aux_header.header_len = GUINT16_FROM_LE (aux_header.header_len); aux_header.width = GUINT16_FROM_LE (aux_header.width); aux_header.height = GUINT16_FROM_LE (aux_header.height); aux_header.frame_interval = GUINT32_FROM_LE (aux_header.frame_interval); aux_header.delay = GUINT16_FROM_LE (aux_header.delay); aux_header.pts = GUINT32_FROM_LE (aux_header.pts); GST_DEBUG_OBJECT (self, "New auxiliary stream : v%d - %d bytes - %" GST_FOURCC_FORMAT " %dx%d -- %d *100ns -- %d ms -- %d", aux_header.version, aux_header.header_len, GST_FOURCC_ARGS (aux_header.type), aux_header.width, aux_header.height, aux_header.frame_interval, aux_header.delay, aux_header.pts); aux_size = *((guint32 *) (info.data + i + aux_header.header_len)); GST_DEBUG_OBJECT (self, "Auxiliary stream size : %d bytes", aux_size); if (aux_size > 0) { guint16 *width = NULL; guint16 *height = NULL; /* Find the auxiliary stream's pad and caps */ switch (aux_header.type) { case GST_MAKE_FOURCC ('H', '2', '6', '4'): aux_pad = self->priv->h264_pad; aux_caps = &self->priv->h264_caps; width = &self->priv->h264_width; height = &self->priv->h264_height; break; case GST_MAKE_FOURCC ('Y', 'U', 'Y', '2'): aux_pad = self->priv->yuy2_pad; aux_caps = &self->priv->yuy2_caps; width = &self->priv->yuy2_width; height = &self->priv->yuy2_height; break; case GST_MAKE_FOURCC ('N', 'V', '1', '2'): aux_pad = self->priv->nv12_pad; aux_caps = &self->priv->nv12_caps; width = &self->priv->nv12_width; height = &self->priv->nv12_height; break; default: GST_ELEMENT_ERROR (self, STREAM, DEMUX, ("Unknown auxiliary stream format : %" GST_FOURCC_FORMAT, GST_FOURCC_ARGS (aux_header.type)), (NULL)); ret = GST_FLOW_ERROR; break; } if (ret != GST_FLOW_OK) goto done; if (*width != aux_header.width || *height != aux_header.height) { GstCaps *peercaps = gst_pad_peer_query_caps (aux_pad, NULL); GstStructure *s = NULL; gint fps_num = 1000000000 / aux_header.frame_interval; gint fps_den = 100; /* TODO: intersect with pad template */ GST_DEBUG ("peercaps : %" GST_PTR_FORMAT, peercaps); if (peercaps && !gst_caps_is_any (peercaps)) { peercaps = gst_caps_make_writable (peercaps); s = gst_caps_get_structure (peercaps, 0); } if (s && gst_structure_has_field (s, "framerate")) { /* TODO: make sure it contains the right format/width/height */ gst_structure_fixate_field_nearest_fraction (s, "framerate", fps_num, fps_den); GST_DEBUG ("Fixated struct : %" GST_PTR_FORMAT, s); gst_structure_get_fraction (s, "framerate", &fps_num, &fps_den); } if (peercaps) gst_caps_unref (peercaps); *width = aux_header.width; *height = aux_header.height; *aux_caps = gst_caps_make_writable (*aux_caps); /* FIXME: fps must match the caps and be allowed and represent our first buffer */ gst_caps_set_simple (*aux_caps, "width", G_TYPE_INT, aux_header.width, "height", G_TYPE_INT, aux_header.height, "framerate", GST_TYPE_FRACTION, fps_num, fps_den, NULL); gst_pad_push_event (aux_pad, gst_event_new_caps (*aux_caps)); gst_pad_push_event (aux_pad, gst_event_new_segment (&self->priv->segment)); } /* Create new auxiliary buffer list and adjust i/segment size */ aux_buf = gst_buffer_new (); } i += sizeof (aux_header) + sizeof (aux_size); segment_size -= sizeof (aux_header) + sizeof (aux_size); } if (segment_size > aux_size) { GST_ELEMENT_ERROR (self, STREAM, DEMUX, ("Expected %d auxiliary data, got %d bytes", aux_size, segment_size), (NULL)); ret = GST_FLOW_ERROR; goto done; } if (segment_size > 0) { GstMemory *m; m = gst_memory_copy (info.memory, i, segment_size); GST_BUFFER_DURATION (aux_buf) = aux_header.frame_interval * 100 * GST_NSECOND; _pts_to_timestamp (self, aux_buf, aux_header.pts); gst_buffer_append_memory (aux_buf, m); aux_size -= segment_size; /* Push completed aux data */ if (aux_size == 0) { GST_DEBUG_OBJECT (self, "Pushing %" GST_FOURCC_FORMAT " auxiliary buffer %" GST_PTR_FORMAT, GST_FOURCC_ARGS (aux_header.type), *aux_caps); ret = gst_pad_push (aux_pad, aux_buf); aux_buf = NULL; if (ret != GST_FLOW_OK) { GST_WARNING_OBJECT (self, "Error pushing %" GST_FOURCC_FORMAT " auxiliary data", GST_FOURCC_ARGS (aux_header.type)); goto done; } } } i += segment_size - 1; } else if (info.data[i] == 0xff && info.data[i + 1] == 0xda) { GstMemory *m; /* The APP4 markers must be before the SOS marker, so this is the end */ GST_DEBUG_OBJECT (self, "Found SOS marker."); m = gst_memory_copy (info.memory, last_offset, info.size - last_offset); gst_buffer_append_memory (jpeg_buf, m); last_offset = info.size; break; } } if (aux_buf != NULL) { GST_DEBUG_OBJECT (self, "Incomplete auxiliary stream: %d bytes missing, " "%d segment size remaining -- missing segment, C920 bug?", aux_size, segment_size); ret = GST_FLOW_OK; goto done; } if (last_offset != info.size) { /* this means there was no SOS marker in the jpg, so we assume the JPG was just a container */ GST_DEBUG_OBJECT (self, "SOS marker wasn't found. MJPG is container only"); gst_buffer_unref (jpeg_buf); jpeg_buf = NULL; } else { ret = gst_pad_push (self->priv->jpeg_pad, jpeg_buf); jpeg_buf = NULL; } if (ret != GST_FLOW_OK) { GST_WARNING_OBJECT (self, "Error pushing jpeg data"); goto done; } done: /* In case of error, unref whatever was left */ if (aux_buf) gst_buffer_unref (aux_buf); if (jpeg_buf) gst_buffer_unref (jpeg_buf); gst_buffer_unmap (buf, &info); /* We must always unref the input buffer since we never push it out */ gst_buffer_unref (buf); return ret; }