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gstreamer/gst/camerabin2/gstwrappercamerabinsrc.c
Thiago Santos 5c20c2e211 wrappercamerabinsrc: fix pad leak 
Only get the pad if it is really going to be used to avoid
leaking it
2015-03-14 18:29:28 +00:00

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/*
* GStreamer
* Copyright (C) 2010 Texas Instruments, Inc
* Copyright (C) 2011 Thiago Santos <thiago.sousa.santos@collabora.com>
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-wrappercamerabinsrc
*
* A camera bin src element that wraps a default video source with a single
* pad into the 3pad model that camerabin2 expects.
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <gst/interfaces/photography.h>
#include "gstwrappercamerabinsrc.h"
#include "camerabingeneral.h"
enum
{
PROP_0,
PROP_VIDEO_SRC,
PROP_VIDEO_SRC_FILTER
};
GST_DEBUG_CATEGORY (wrapper_camera_bin_src_debug);
#define GST_CAT_DEFAULT wrapper_camera_bin_src_debug
#define gst_wrapper_camera_bin_src_parent_class parent_class
G_DEFINE_TYPE (GstWrapperCameraBinSrc, gst_wrapper_camera_bin_src,
GST_TYPE_BASE_CAMERA_SRC);
static GstStaticPadTemplate vfsrc_template =
GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_VIEWFINDER_PAD_NAME,
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate imgsrc_template =
GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_IMAGE_PAD_NAME,
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate vidsrc_template =
GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_VIDEO_PAD_NAME,
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static void set_capsfilter_caps (GstWrapperCameraBinSrc * self,
GstCaps * new_caps);
static void
gst_wrapper_camera_bin_src_dispose (GObject * object)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (object);
if (self->outsel_imgpad) {
gst_object_unref (self->outsel_imgpad);
self->outsel_imgpad = NULL;
}
if (self->outsel_vidpad) {
gst_object_unref (self->outsel_vidpad);
self->outsel_vidpad = NULL;
}
if (self->app_vid_src) {
gst_object_unref (self->app_vid_src);
self->app_vid_src = NULL;
}
if (self->app_vid_filter) {
gst_object_unref (self->app_vid_filter);
self->app_vid_filter = NULL;
}
if (self->srcfilter_pad) {
gst_object_unref (self->srcfilter_pad);
self->srcfilter_pad = NULL;
}
gst_caps_replace (&self->image_capture_caps, NULL);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_wrapper_camera_bin_src_finalize (GstWrapperCameraBinSrc * self)
{
G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (self));
}
static void
gst_wrapper_camera_bin_src_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (object);
switch (prop_id) {
case PROP_VIDEO_SRC:
if (GST_STATE (self) != GST_STATE_NULL) {
GST_ELEMENT_ERROR (self, CORE, FAILED,
("camerasrc must be in NULL state when setting the video source element"),
(NULL));
} else {
if (self->app_vid_src)
gst_object_unref (self->app_vid_src);
self->app_vid_src = g_value_get_object (value);
if (self->app_vid_src)
gst_object_ref (self->app_vid_src);
}
break;
case PROP_VIDEO_SRC_FILTER:
if (GST_STATE (self) != GST_STATE_NULL) {
GST_ELEMENT_ERROR (self, CORE, FAILED,
("camerasrc must be in NULL state when setting the video source filter element"),
(NULL));
} else {
if (self->app_vid_filter)
gst_object_unref (self->app_vid_filter);
self->app_vid_filter = g_value_get_object (value);
if (self->app_vid_filter)
gst_object_ref (self->app_vid_filter);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
break;
}
}
static void
gst_wrapper_camera_bin_src_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (object);
switch (prop_id) {
case PROP_VIDEO_SRC:
if (self->src_vid_src)
g_value_set_object (value, self->src_vid_src);
else
g_value_set_object (value, self->app_vid_src);
break;
case PROP_VIDEO_SRC_FILTER:
if (self->video_filter)
g_value_set_object (value, self->video_filter);
else
g_value_set_object (value, self->app_vid_filter);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
break;
}
}
static void
gst_wrapper_camera_bin_reset_video_src_caps (GstWrapperCameraBinSrc * self,
GstCaps * new_filter_caps)
{
GST_DEBUG_OBJECT (self, "Resetting src caps to %" GST_PTR_FORMAT,
new_filter_caps);
if (self->src_vid_src) {
GstCaps *src_neg_caps; /* negotiated caps on src_filter */
gboolean ret = FALSE;
/* After pipe was negotiated src_filter do not have any filter caps.
* In this situation we should compare neogotiated caps on capsfilter pad
* with requested range of caps. If one of this caps intersect,
* then we can avoid reseting.
*/
src_neg_caps = gst_pad_get_current_caps (self->srcfilter_pad);
if (src_neg_caps && new_filter_caps && gst_caps_is_fixed (new_filter_caps))
ret = gst_caps_can_intersect (src_neg_caps, new_filter_caps);
else if (new_filter_caps == NULL) {
/* If new_filter_caps = NULL, then some body wont to empty
* capsfilter (set to ANY). In this case we will need to reset pipe,
* but if capsfilter is actually empthy, then we can avoid
* one more reseting.
*/
GstCaps *old_filter_caps; /* range of caps on capsfilter */
g_object_get (G_OBJECT (self->src_filter),
"caps", &old_filter_caps, NULL);
ret = gst_caps_is_any (old_filter_caps);
gst_caps_unref (old_filter_caps);
}
if (src_neg_caps)
gst_caps_unref (src_neg_caps);
if (ret) {
GST_DEBUG_OBJECT (self, "Negotiated caps on srcfilter intersect "
"with requested caps, do not reset it.");
return;
}
set_capsfilter_caps (self, new_filter_caps);
}
}
/**
* gst_wrapper_camera_bin_src_imgsrc_probe:
*
* Buffer probe called before sending each buffer to image queue.
*/
static GstPadProbeReturn
gst_wrapper_camera_bin_src_imgsrc_probe (GstPad * pad, GstPadProbeInfo * info,
gpointer data)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (data);
GstBaseCameraSrc *camerasrc = GST_BASE_CAMERA_SRC (data);
GstBuffer *buffer = GST_BUFFER (info->data);
GstPadProbeReturn ret = GST_PAD_PROBE_DROP;
GST_LOG_OBJECT (self, "Image probe, mode %d, capture count %d bufsize: %"
G_GSIZE_FORMAT, camerasrc->mode, self->image_capture_count,
gst_buffer_get_size (buffer));
g_mutex_lock (&camerasrc->capturing_mutex);
if (self->image_capture_count > 0) {
GstSample *sample;
GstCaps *caps;
ret = GST_PAD_PROBE_OK;
self->image_capture_count--;
/* post preview */
/* TODO This can likely be optimized if the viewfinder caps is the same as
* the preview caps, avoiding another scaling of the same buffer. */
GST_DEBUG_OBJECT (self, "Posting preview for image");
caps = gst_pad_get_current_caps (pad);
sample = gst_sample_new (buffer, caps, NULL, NULL);
gst_base_camera_src_post_preview (camerasrc, sample);
gst_caps_unref (caps);
gst_sample_unref (sample);
if (self->image_capture_count == 0) {
gst_base_camera_src_finish_capture (camerasrc);
}
}
g_mutex_unlock (&camerasrc->capturing_mutex);
return ret;
}
/**
* gst_wrapper_camera_bin_src_vidsrc_probe:
*
* Buffer probe called before sending each buffer to image queue.
*/
static GstPadProbeReturn
gst_wrapper_camera_bin_src_vidsrc_probe (GstPad * pad, GstPadProbeInfo * info,
gpointer data)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (data);
GstBaseCameraSrc *camerasrc = GST_BASE_CAMERA_SRC_CAST (self);
GstPadProbeReturn ret = GST_PAD_PROBE_DROP;
GstBuffer *buffer = GST_BUFFER (info->data);
GST_LOG_OBJECT (self, "Video probe, mode %d, capture status %d",
camerasrc->mode, self->video_rec_status);
/* TODO do we want to lock for every buffer? */
/*
* Note that we can use gst_pad_push_event here because we are a buffer
* probe.
*/
/* TODO shouldn't access this directly */
g_mutex_lock (&camerasrc->capturing_mutex);
if (self->video_rec_status == GST_VIDEO_RECORDING_STATUS_DONE) {
/* NOP */
} else if (self->video_rec_status == GST_VIDEO_RECORDING_STATUS_STARTING) {
GstClockTime ts;
GstSegment segment;
GstCaps *caps;
GstSample *sample;
GST_DEBUG_OBJECT (self, "Starting video recording");
self->video_rec_status = GST_VIDEO_RECORDING_STATUS_RUNNING;
ts = GST_BUFFER_TIMESTAMP (buffer);
if (!GST_CLOCK_TIME_IS_VALID (ts))
ts = 0;
gst_segment_init (&segment, GST_FORMAT_TIME);
segment.start = ts;
gst_pad_push_event (self->vidsrc, gst_event_new_segment (&segment));
/* post preview */
GST_DEBUG_OBJECT (self, "Posting preview for video");
caps = gst_pad_get_current_caps (pad);
sample = gst_sample_new (buffer, caps, NULL, NULL);
gst_base_camera_src_post_preview (camerasrc, sample);
gst_caps_unref (caps);
gst_sample_unref (sample);
ret = GST_PAD_PROBE_OK;
} else if (self->video_rec_status == GST_VIDEO_RECORDING_STATUS_FINISHING) {
GstPad *peer;
/* send eos */
GST_DEBUG_OBJECT (self, "Finishing video recording, pushing eos");
peer = gst_pad_get_peer (self->vidsrc);
if (peer) {
/* send to the peer as we don't want our pads with eos flag */
gst_pad_send_event (peer, gst_event_new_eos ());
gst_object_unref (peer);
} else {
GST_WARNING_OBJECT (camerasrc, "No peer pad for vidsrc");
}
self->video_rec_status = GST_VIDEO_RECORDING_STATUS_DONE;
gst_base_camera_src_finish_capture (camerasrc);
} else {
ret = GST_PAD_PROBE_OK;
}
g_mutex_unlock (&camerasrc->capturing_mutex);
return ret;
}
static GstPadProbeReturn
gst_wrapper_camera_src_src_event_probe (GstPad * pad, GstPadProbeInfo * info,
gpointer udata)
{
GstPadProbeReturn ret = GST_PAD_PROBE_OK;
GstWrapperCameraBinSrc *self = udata;
GstEvent *evt = GST_EVENT (info->data);
switch (GST_EVENT_TYPE (evt)) {
case GST_EVENT_SEGMENT:
if (self->drop_newseg) {
ret = GST_PAD_PROBE_DROP;
self->drop_newseg = FALSE;
}
break;
default:
break;
}
return ret;
}
static void
gst_wrapper_camera_bin_src_caps_cb (GstPad * pad, GParamSpec * pspec,
gpointer user_data)
{
GstBaseCameraSrc *bcamsrc = GST_BASE_CAMERA_SRC (user_data);
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (user_data);
GstCaps *caps;
GstStructure *in_st = NULL;
caps = gst_pad_get_current_caps (pad);
GST_DEBUG_OBJECT (self, "src-filter caps changed to %" GST_PTR_FORMAT, caps);
if (caps && gst_caps_get_size (caps)) {
in_st = gst_caps_get_structure (caps, 0);
if (in_st) {
gst_structure_get_int (in_st, "width", &bcamsrc->width);
gst_structure_get_int (in_st, "height", &bcamsrc->height);
GST_DEBUG_OBJECT (self, "Source dimensions now: %dx%d", bcamsrc->width,
bcamsrc->height);
}
}
/* Update zoom */
gst_base_camera_src_setup_zoom (bcamsrc);
/* Update post-zoom capsfilter */
if (self->src_zoom_filter) {
GstCaps *filtercaps;
g_object_get (G_OBJECT (self->src_zoom_filter), "caps", &filtercaps, NULL);
if (caps != filtercaps && (caps == NULL || filtercaps == NULL ||
!gst_caps_is_equal (filtercaps, caps)))
g_object_set (G_OBJECT (self->src_zoom_filter), "caps", caps, NULL);
if (filtercaps)
gst_caps_unref (filtercaps);
}
if (caps)
gst_caps_unref (caps);
};
static void
gst_wrapper_camera_bin_src_max_zoom_cb (GObject * self, GParamSpec * pspec,
gpointer user_data)
{
GstBaseCameraSrc *bcamsrc = (GstBaseCameraSrc *) user_data;
g_object_get (self, "max-zoom", &bcamsrc->max_zoom, NULL);
g_object_notify (G_OBJECT (bcamsrc), "max-zoom");
}
static gboolean
gst_wrapper_camera_bin_src_src_event (GstPad * pad, GstObject * parent,
GstEvent * event)
{
gboolean ret = TRUE;
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (parent);
GstPad *upstream_pad = NULL;
GST_DEBUG_OBJECT (self, "Handling event %p %" GST_PTR_FORMAT, event, event);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_RECONFIGURE:
if (pad == self->imgsrc) {
GST_DEBUG_OBJECT (self, "Image mode reconfigure event received");
self->image_renegotiate = TRUE;
} else if (pad == self->vidsrc) {
GST_DEBUG_OBJECT (self, "Video mode reconfigure event received");
self->video_renegotiate = TRUE;
}
if (pad == self->imgsrc || pad == self->vidsrc) {
gst_event_unref (event);
return ret;
}
break;
default:
break;
}
if (pad == self->imgsrc) {
upstream_pad = self->outsel_imgpad;
} else if (pad == self->vidsrc) {
upstream_pad = self->outsel_vidpad;
}
if (upstream_pad) {
ret = gst_pad_send_event (upstream_pad, event);
} else {
GST_WARNING_OBJECT (self, "Event caught that doesn't have an upstream pad -"
"this shouldn't be possible!");
gst_event_unref (event);
ret = FALSE;
}
return ret;
}
/**
* check_and_replace_src
* @self: #GstWrapperCamerabinSrcCameraSrc object
*
* Checks if the current videosrc needs to be replaced
*/
static gboolean
check_and_replace_src (GstWrapperCameraBinSrc * self)
{
GstBin *cbin = GST_BIN_CAST (self);
GstBaseCameraSrc *bcamsrc = GST_BASE_CAMERA_SRC_CAST (self);
GstElement *videoconvert;
if (self->src_vid_src && self->src_vid_src == self->app_vid_src) {
GST_DEBUG_OBJECT (self, "No need to change current videosrc");
return TRUE;
}
if (self->src_vid_src) {
GST_DEBUG_OBJECT (self, "Removing old video source");
if (self->src_max_zoom_signal_id) {
g_signal_handler_disconnect (self->src_vid_src,
self->src_max_zoom_signal_id);
self->src_max_zoom_signal_id = 0;
}
if (self->src_event_probe_id) {
GstPad *pad;
pad = gst_element_get_static_pad (self->src_vid_src, "src");
gst_pad_remove_probe (pad, self->src_event_probe_id);
gst_object_unref (pad);
self->src_event_probe_id = 0;
}
gst_bin_remove (GST_BIN_CAST (self), self->src_vid_src);
self->src_vid_src = NULL;
}
GST_DEBUG_OBJECT (self, "Adding new video source");
/* Add application set or default video src element */
if (!(self->src_vid_src = gst_camerabin_setup_default_element (cbin,
self->app_vid_src, "autovideosrc", DEFAULT_VIDEOSRC,
"camerasrc-real-src"))) {
self->src_vid_src = NULL;
return FALSE;
}
if (!gst_bin_add (cbin, self->src_vid_src)) {
return FALSE;
}
/* check if we already have the next element to link to */
videoconvert = gst_bin_get_by_name (cbin, "src-videoconvert");
if (videoconvert) {
if (!gst_element_link_pads (self->src_vid_src, "src", videoconvert, "sink")) {
gst_object_unref (videoconvert);
return FALSE;
}
gst_object_unref (videoconvert);
}
/* we listen for changes to max-zoom in the video src so that
* we can proxy them to the basecamerasrc property */
if (g_object_class_find_property (G_OBJECT_GET_CLASS (bcamsrc), "max-zoom")) {
self->src_max_zoom_signal_id =
g_signal_connect (G_OBJECT (self->src_vid_src), "notify::max-zoom",
(GCallback) gst_wrapper_camera_bin_src_max_zoom_cb, bcamsrc);
}
/* add a buffer probe to the src elemento to drop EOS from READY->NULL */
{
GstPad *pad;
pad = gst_element_get_static_pad (self->src_vid_src, "src");
self->src_event_probe_id =
gst_pad_add_probe (pad, GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM,
gst_wrapper_camera_src_src_event_probe, self, NULL);
gst_object_unref (pad);
}
return TRUE;
}
/**
* gst_wrapper_camera_bin_src_construct_pipeline:
* @bcamsrc: camerasrc object
*
* This function creates and links the elements of the camerasrc bin
* videosrc ! cspconv ! srcfilter ! cspconv ! capsfilter ! crop ! scale ! \
* capsfilter ! tee name=t
* t. ! ... (viewfinder pad)
* t. ! output-selector name=outsel
* outsel. ! (image pad)
* outsel. ! (video pad)
*
* Returns: TRUE, if elements were successfully created, FALSE otherwise
*/
static gboolean
gst_wrapper_camera_bin_src_construct_pipeline (GstBaseCameraSrc * bcamsrc)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (bcamsrc);
GstBin *cbin = GST_BIN (bcamsrc);
GstElement *tee;
GstElement *filter_csp;
GstElement *src_csp;
GstElement *capsfilter;
gboolean ret = FALSE;
GstPad *vf_pad;
GstPad *tee_capture_pad;
/* checks and adds a new video src if needed */
if (!check_and_replace_src (self))
goto done;
if (!self->elements_created) {
GST_DEBUG_OBJECT (self, "constructing pipeline");
if (!gst_camerabin_create_and_add_element (cbin, "videoconvert",
"src-videoconvert"))
goto done;
if (self->app_vid_filter) {
self->video_filter = gst_object_ref (self->app_vid_filter);
if (!gst_camerabin_add_element (cbin, self->video_filter))
goto done;
if (!gst_camerabin_create_and_add_element (cbin, "videoconvert",
"filter-videoconvert"))
goto done;
}
if (!(self->src_filter =
gst_camerabin_create_and_add_element (cbin, "capsfilter",
"src-capsfilter")))
goto done;
/* attach to notify::caps on the first capsfilter and use a callback
* to recalculate the zoom properties when these caps change and to
* propagate the caps to the second capsfilter */
self->srcfilter_pad = gst_element_get_static_pad (self->src_filter, "src");
g_signal_connect (self->srcfilter_pad, "notify::caps",
G_CALLBACK (gst_wrapper_camera_bin_src_caps_cb), self);
if (!(self->src_zoom_crop =
gst_camerabin_create_and_add_element (cbin, "videocrop",
"zoom-crop")))
goto done;
if (!(self->src_zoom_scale =
gst_camerabin_create_and_add_element (cbin, "videoscale",
"zoom-scale")))
goto done;
if (!(self->src_zoom_filter =
gst_camerabin_create_and_add_element (cbin, "capsfilter",
"zoom-capsfilter")))
goto done;
if (!(tee =
gst_camerabin_create_and_add_element (cbin, "tee",
"camerasrc-tee")))
goto done;
/* viewfinder pad */
vf_pad = gst_element_get_request_pad (tee, "src_%u");
g_object_set (tee, "alloc-pad", vf_pad, NULL);
gst_ghost_pad_set_target (GST_GHOST_PAD (self->vfsrc), vf_pad);
gst_object_unref (vf_pad);
/* image/video pad from tee */
tee_capture_pad = gst_element_get_request_pad (tee, "src_%u");
self->output_selector =
gst_element_factory_make ("output-selector", "outsel");
g_object_set (self->output_selector, "pad-negotiation-mode", 2, NULL);
gst_bin_add (GST_BIN (self), self->output_selector);
{
GstPad *pad = gst_element_get_static_pad (self->output_selector, "sink");
/* check return TODO */
gst_pad_link (tee_capture_pad, pad);
gst_object_unref (pad);
}
gst_object_unref (tee_capture_pad);
/* Create the 2 output pads for video and image */
self->outsel_vidpad =
gst_element_get_request_pad (self->output_selector, "src_%u");
self->outsel_imgpad =
gst_element_get_request_pad (self->output_selector, "src_%u");
g_assert (self->outsel_vidpad != NULL);
g_assert (self->outsel_imgpad != NULL);
gst_pad_add_probe (self->outsel_imgpad, GST_PAD_PROBE_TYPE_BUFFER,
gst_wrapper_camera_bin_src_imgsrc_probe, self, NULL);
gst_pad_add_probe (self->outsel_vidpad, GST_PAD_PROBE_TYPE_BUFFER,
gst_wrapper_camera_bin_src_vidsrc_probe, self, NULL);
gst_ghost_pad_set_target (GST_GHOST_PAD (self->imgsrc),
self->outsel_imgpad);
gst_ghost_pad_set_target (GST_GHOST_PAD (self->vidsrc),
self->outsel_vidpad);
if (bcamsrc->mode == MODE_IMAGE) {
g_object_set (self->output_selector, "active-pad", self->outsel_imgpad,
NULL);
} else {
g_object_set (self->output_selector, "active-pad", self->outsel_vidpad,
NULL);
}
gst_pad_set_active (self->vfsrc, TRUE);
gst_pad_set_active (self->imgsrc, TRUE); /* XXX ??? */
gst_pad_set_active (self->vidsrc, TRUE); /* XXX ??? */
}
/* Do this even if pipeline is constructed */
if (self->video_filter) {
/* check if we need to replace the current one */
if (self->video_filter != self->app_vid_filter) {
gst_bin_remove (cbin, self->video_filter);
gst_object_unref (self->video_filter);
self->video_filter = NULL;
filter_csp = gst_bin_get_by_name (cbin, "filter-videoconvert");
gst_bin_remove (cbin, filter_csp);
gst_object_unref (filter_csp);
filter_csp = NULL;
}
}
if (!self->video_filter) {
if (self->app_vid_filter) {
self->video_filter = gst_object_ref (self->app_vid_filter);
filter_csp = gst_element_factory_make ("videoconvert",
"filter-videoconvert");
gst_bin_add_many (cbin, self->video_filter, filter_csp, NULL);
src_csp = gst_bin_get_by_name (cbin, "src-videoconvert");
capsfilter = gst_bin_get_by_name (cbin, "src-capsfilter");
if (gst_pad_is_linked (gst_element_get_static_pad (src_csp, "src")))
gst_element_unlink (src_csp, capsfilter);
if (!gst_element_link_many (src_csp, self->video_filter, filter_csp,
capsfilter, NULL)) {
gst_object_unref (src_csp);
gst_object_unref (capsfilter);
goto done;
}
gst_object_unref (src_csp);
gst_object_unref (capsfilter);
}
}
ret = TRUE;
self->elements_created = TRUE;
done:
return ret;
}
static gboolean
copy_missing_fields (GQuark field_id, const GValue * value, gpointer user_data)
{
GstStructure *st = (GstStructure *) user_data;
const GValue *val = gst_structure_id_get_value (st, field_id);
if (G_UNLIKELY (val == NULL)) {
gst_structure_id_set_value (st, field_id, value);
}
return TRUE;
}
/**
* adapt_image_capture:
* @self: camerasrc object
* @in_caps: caps object that describes incoming image format
*
* Adjust capsfilters and crop according image capture caps if necessary.
* The captured image format from video source might be different from
* what application requested, so we can try to fix that in camerabin.
*
*/
static void
adapt_image_capture (GstWrapperCameraBinSrc * self, GstCaps * in_caps)
{
GstBaseCameraSrc *bcamsrc = GST_BASE_CAMERA_SRC (self);
GstStructure *in_st, *new_st, *req_st;
gint in_width = 0, in_height = 0, req_width = 0, req_height = 0, crop = 0;
gdouble ratio_w, ratio_h;
GstCaps *filter_caps = NULL;
GST_LOG_OBJECT (self, "in caps: %" GST_PTR_FORMAT, in_caps);
GST_LOG_OBJECT (self, "requested caps: %" GST_PTR_FORMAT,
self->image_capture_caps);
in_st = gst_caps_get_structure (in_caps, 0);
gst_structure_get_int (in_st, "width", &in_width);
gst_structure_get_int (in_st, "height", &in_height);
req_st = gst_caps_get_structure (self->image_capture_caps, 0);
gst_structure_get_int (req_st, "width", &req_width);
gst_structure_get_int (req_st, "height", &req_height);
GST_INFO_OBJECT (self, "we requested %dx%d, and got %dx%d", req_width,
req_height, in_width, in_height);
new_st = gst_structure_copy (req_st);
/* If new fields have been added, we need to copy them */
gst_structure_foreach (in_st, copy_missing_fields, new_st);
gst_structure_set (new_st, "width", G_TYPE_INT, in_width, "height",
G_TYPE_INT, in_height, NULL);
GST_LOG_OBJECT (self, "new image capture caps: %" GST_PTR_FORMAT, new_st);
/* Crop if requested aspect ratio differs from incoming frame aspect ratio */
if (self->src_zoom_crop) {
ratio_w = (gdouble) in_width / req_width;
ratio_h = (gdouble) in_height / req_height;
if (ratio_w < ratio_h) {
crop = in_height - (req_height * ratio_w);
self->base_crop_top = crop / 2;
self->base_crop_bottom = crop / 2;
} else {
crop = in_width - (req_width * ratio_h);
self->base_crop_left = crop / 2;
self->base_crop_right += crop / 2;
}
GST_INFO_OBJECT (self,
"setting base crop: left:%d, right:%d, top:%d, bottom:%d",
self->base_crop_left, self->base_crop_right, self->base_crop_top,
self->base_crop_bottom);
g_object_set (G_OBJECT (self->src_zoom_crop),
"top", self->base_crop_top,
"bottom", self->base_crop_bottom,
"left", self->base_crop_left, "right", self->base_crop_right, NULL);
}
/* Update capsfilters */
if (self->image_capture_caps) {
gst_caps_unref (self->image_capture_caps);
}
self->image_capture_caps = gst_caps_new_full (new_st, NULL);
set_capsfilter_caps (self, self->image_capture_caps);
/* Adjust the capsfilter before crop and videoscale elements if necessary */
if (in_width == bcamsrc->width && in_height == bcamsrc->height) {
GST_DEBUG_OBJECT (self, "no adaptation with resolution needed");
} else {
GST_DEBUG_OBJECT (self,
"changing %" GST_PTR_FORMAT " from %dx%d to %dx%d", self->src_filter,
bcamsrc->width, bcamsrc->height, in_width, in_height);
/* Apply the width and height to filter caps */
g_object_get (G_OBJECT (self->src_filter), "caps", &filter_caps, NULL);
filter_caps = gst_caps_make_writable (filter_caps);
gst_caps_set_simple (filter_caps, "width", G_TYPE_INT, in_width, "height",
G_TYPE_INT, in_height, NULL);
g_object_set (G_OBJECT (self->src_filter), "caps", filter_caps, NULL);
gst_caps_unref (filter_caps);
}
}
/**
* img_capture_prepared:
* @data: camerasrc object
* @caps: caps describing the prepared image format
*
* Callback which is called after image capture has been prepared.
*/
static void
img_capture_prepared (gpointer data, GstCaps * caps)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (data);
GST_INFO_OBJECT (self, "image capture prepared");
/* It is possible we are about to get something else that we requested */
if (!gst_caps_is_equal (self->image_capture_caps, caps)) {
adapt_image_capture (self, caps);
} else {
set_capsfilter_caps (self, self->image_capture_caps);
}
}
/**
*
*/
static gboolean
start_image_capture (GstWrapperCameraBinSrc * self)
{
GstBaseCameraSrc *bcamsrc = GST_BASE_CAMERA_SRC (self);
GstPhotography *photography =
(GstPhotography *) gst_bin_get_by_interface (GST_BIN_CAST (bcamsrc),
GST_TYPE_PHOTOGRAPHY);
gboolean ret = FALSE;
GstCaps *caps;
GST_DEBUG_OBJECT (self, "Starting image capture");
/* V4L2 source will not close the device until all buffers have came
* back. Draining the pipeline, will ensure it's properly closed, and that
* setting it back to PLAYING will work. */
if (self->image_renegotiate) {
GstPad *pad, *peer;
g_mutex_unlock (&bcamsrc->capturing_mutex);
pad = gst_element_get_static_pad (self->src_vid_src, "src");
peer = gst_pad_get_peer (pad);
gst_object_unref (pad);
gst_pad_query (peer, gst_query_new_drain ());
gst_object_unref (peer);
self->image_renegotiate = FALSE;
gst_element_set_state (self->src_vid_src, GST_STATE_READY);
/* clean capsfilter caps so they don't interfere here */
g_object_set (self->src_filter, "caps", NULL, NULL);
if (self->src_zoom_filter)
g_object_set (self->src_zoom_filter, "caps", NULL, NULL);
caps = gst_pad_get_allowed_caps (self->imgsrc);
gst_caps_replace (&self->image_capture_caps, caps);
gst_caps_unref (caps);
/* FIXME - do we need to update basecamerasrc width/height somehow here?
* if not, i think we need to do something about _when_ they get updated
* to be sure that set_element_zoom doesn't use the wrong values */
/* We caught this event in the src pad event handler and now we want to
* actually push it upstream */
gst_pad_send_event (self->outsel_imgpad, gst_event_new_reconfigure ());
g_mutex_lock (&bcamsrc->capturing_mutex);
}
if (photography) {
gst_element_set_state (self->src_vid_src, GST_STATE_PLAYING);
GST_DEBUG_OBJECT (self, "prepare image capture caps %" GST_PTR_FORMAT,
self->image_capture_caps);
ret = gst_photography_prepare_for_capture (photography,
(GstPhotographyCapturePrepared) img_capture_prepared,
self->image_capture_caps, self);
gst_object_unref (photography);
} else {
g_mutex_unlock (&bcamsrc->capturing_mutex);
gst_wrapper_camera_bin_reset_video_src_caps (self,
self->image_capture_caps);
g_mutex_lock (&bcamsrc->capturing_mutex);
ret = TRUE;
gst_element_set_state (self->src_vid_src, GST_STATE_PLAYING);
}
return ret;
}
static gboolean
gst_wrapper_camera_bin_src_set_mode (GstBaseCameraSrc * bcamsrc,
GstCameraBinMode mode)
{
GstPhotography *photography =
(GstPhotography *) gst_bin_get_by_interface (GST_BIN_CAST (bcamsrc),
GST_TYPE_PHOTOGRAPHY);
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (bcamsrc);
if (self->output_selector) {
if (mode == MODE_IMAGE) {
self->image_renegotiate = TRUE;
g_object_set (self->output_selector, "active-pad", self->outsel_imgpad,
NULL);
} else {
self->video_renegotiate = TRUE;
g_object_set (self->output_selector, "active-pad", self->outsel_vidpad,
NULL);
}
}
self->mode = mode;
if (photography) {
if (g_object_class_find_property (G_OBJECT_GET_CLASS (photography),
"capture-mode")) {
g_object_set (G_OBJECT (photography), "capture-mode", mode, NULL);
}
gst_object_unref (photography);
} else {
GstCaps *anycaps = gst_caps_new_any ();
gst_wrapper_camera_bin_reset_video_src_caps (self, anycaps);
gst_caps_unref (anycaps);
}
return TRUE;
}
static gboolean
set_videosrc_zoom (GstWrapperCameraBinSrc * self, gfloat zoom)
{
gboolean ret = FALSE;
if (g_object_class_find_property (G_OBJECT_GET_CLASS (self->src_vid_src),
"zoom")) {
g_object_set (G_OBJECT (self->src_vid_src), "zoom", zoom, NULL);
ret = TRUE;
}
return ret;
}
static gboolean
set_element_zoom (GstWrapperCameraBinSrc * self, gfloat zoom)
{
gboolean ret = FALSE;
GstBaseCameraSrc *bcamsrc = GST_BASE_CAMERA_SRC (self);
gint w2_crop = 0, h2_crop = 0;
GstPad *pad_zoom_sink = NULL;
gint left = self->base_crop_left;
gint right = self->base_crop_right;
gint top = self->base_crop_top;
gint bottom = self->base_crop_bottom;
if (self->src_zoom_crop) {
/* Update capsfilters to apply the zoom */
GST_INFO_OBJECT (self, "zoom: %f, orig size: %dx%d", zoom,
bcamsrc->width, bcamsrc->height);
if (zoom != ZOOM_1X) {
w2_crop = (bcamsrc->width - (gint) (bcamsrc->width * ZOOM_1X / zoom)) / 2;
h2_crop =
(bcamsrc->height - (gint) (bcamsrc->height * ZOOM_1X / zoom)) / 2;
left += w2_crop;
right += w2_crop;
top += h2_crop;
bottom += h2_crop;
/* force number of pixels cropped from left to be even, to avoid slow code
* path on videoscale */
left &= 0xFFFE;
}
pad_zoom_sink = gst_element_get_static_pad (self->src_zoom_crop, "sink");
GST_INFO_OBJECT (self,
"sw cropping: left:%d, right:%d, top:%d, bottom:%d", left, right, top,
bottom);
GST_PAD_STREAM_LOCK (pad_zoom_sink);
g_object_set (self->src_zoom_crop, "left", left, "right", right, "top",
top, "bottom", bottom, NULL);
GST_PAD_STREAM_UNLOCK (pad_zoom_sink);
gst_object_unref (pad_zoom_sink);
ret = TRUE;
}
return ret;
}
static void
gst_wrapper_camera_bin_src_set_zoom (GstBaseCameraSrc * bcamsrc, gfloat zoom)
{
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (bcamsrc);
GST_INFO_OBJECT (self, "setting zoom %f", zoom);
if (set_videosrc_zoom (self, zoom)) {
set_element_zoom (self, ZOOM_1X);
GST_INFO_OBJECT (self, "zoom set using videosrc");
} else if (set_element_zoom (self, zoom)) {
GST_INFO_OBJECT (self, "zoom set using gst elements");
} else {
GST_INFO_OBJECT (self, "setting zoom failed");
}
}
/**
* update_aspect_filter:
* @self: camerasrc object
* @new_caps: new caps of next buffers arriving to view finder sink element
*
* Updates aspect ratio capsfilter to maintain aspect ratio, if we need to
* scale frames for showing them in view finder.
*/
static void
update_aspect_filter (GstWrapperCameraBinSrc * self, GstCaps * new_caps)
{
// XXX why not instead add a preserve-aspect-ratio property to videoscale?
#if 0
if (camera->flags & GST_CAMERABIN_FLAG_VIEWFINDER_SCALE) {
GstCaps *sink_caps, *ar_caps;
GstStructure *st;
gint in_w = 0, in_h = 0, sink_w = 0, sink_h = 0, target_w = 0, target_h = 0;
gdouble ratio_w, ratio_h;
GstPad *sink_pad;
const GValue *range;
sink_pad = gst_element_get_static_pad (camera->view_sink, "sink");
if (sink_pad) {
sink_caps = gst_pad_get_caps (sink_pad);
gst_object_unref (sink_pad);
if (sink_caps) {
if (!gst_caps_is_any (sink_caps)) {
GST_DEBUG_OBJECT (camera, "sink element caps %" GST_PTR_FORMAT,
sink_caps);
/* Get maximum resolution that view finder sink accepts */
st = gst_caps_get_structure (sink_caps, 0);
if (gst_structure_has_field_typed (st, "width", GST_TYPE_INT_RANGE)) {
range = gst_structure_get_value (st, "width");
sink_w = gst_value_get_int_range_max (range);
}
if (gst_structure_has_field_typed (st, "height", GST_TYPE_INT_RANGE)) {
range = gst_structure_get_value (st, "height");
sink_h = gst_value_get_int_range_max (range);
}
GST_DEBUG_OBJECT (camera, "sink element accepts max %dx%d", sink_w,
sink_h);
/* Get incoming frames' resolution */
if (sink_h && sink_w) {
st = gst_caps_get_structure (new_caps, 0);
gst_structure_get_int (st, "width", &in_w);
gst_structure_get_int (st, "height", &in_h);
GST_DEBUG_OBJECT (camera, "new caps with %dx%d", in_w, in_h);
}
}
gst_caps_unref (sink_caps);
}
}
/* If we get bigger frames than view finder sink accepts, then we scale.
If we scale we need to adjust aspect ratio capsfilter caps in order
to maintain aspect ratio while scaling. */
if (in_w && in_h && (in_w > sink_w || in_h > sink_h)) {
ratio_w = (gdouble) sink_w / in_w;
ratio_h = (gdouble) sink_h / in_h;
if (ratio_w < ratio_h) {
target_w = sink_w;
target_h = (gint) (ratio_w * in_h);
} else {
target_w = (gint) (ratio_h * in_w);
target_h = sink_h;
}
GST_DEBUG_OBJECT (camera, "setting %dx%d filter to maintain aspect ratio",
target_w, target_h);
ar_caps = gst_caps_copy (new_caps);
gst_caps_set_simple (ar_caps, "width", G_TYPE_INT, target_w, "height",
G_TYPE_INT, target_h, NULL);
} else {
GST_DEBUG_OBJECT (camera, "no scaling");
ar_caps = new_caps;
}
GST_DEBUG_OBJECT (camera, "aspect ratio filter caps %" GST_PTR_FORMAT,
ar_caps);
g_object_set (G_OBJECT (camera->aspect_filter), "caps", ar_caps, NULL);
if (ar_caps != new_caps)
gst_caps_unref (ar_caps);
}
#endif
}
/**
* set_capsfilter_caps:
* @self: camerasrc object
* @new_caps: pointer to caps object to set
*
* Set given caps to camerabin capsfilters.
*/
static void
set_capsfilter_caps (GstWrapperCameraBinSrc * self, GstCaps * new_caps)
{
GST_INFO_OBJECT (self, "new_caps:%" GST_PTR_FORMAT, new_caps);
/* Update zoom */
gst_base_camera_src_setup_zoom (GST_BASE_CAMERA_SRC (self));
/* Update capsfilters */
g_object_set (G_OBJECT (self->src_filter), "caps", new_caps, NULL);
if (self->src_zoom_filter)
g_object_set (G_OBJECT (self->src_zoom_filter), "caps", new_caps, NULL);
update_aspect_filter (self, new_caps);
GST_INFO_OBJECT (self, "updated");
}
static gboolean
gst_wrapper_camera_bin_src_start_capture (GstBaseCameraSrc * camerasrc)
{
GstWrapperCameraBinSrc *src = GST_WRAPPER_CAMERA_BIN_SRC (camerasrc);
/* TODO should we access this directly? Maybe a macro is better? */
if (src->mode == MODE_IMAGE) {
start_image_capture (src);
src->image_capture_count = 1;
} else if (src->mode == MODE_VIDEO) {
GstCaps *caps = NULL;
if (src->video_renegotiate) {
GstCaps *anycaps = gst_caps_new_any ();
g_mutex_unlock (&camerasrc->capturing_mutex);
gst_wrapper_camera_bin_reset_video_src_caps (src, anycaps);
g_mutex_lock (&camerasrc->capturing_mutex);
/* clean capsfilter caps so they don't interfere here */
g_object_set (src->src_filter, "caps", NULL, NULL);
if (src->src_zoom_filter)
g_object_set (src->src_zoom_filter, "caps", NULL, NULL);
GST_DEBUG_OBJECT (src, "Getting allowed videosrc caps");
caps = gst_pad_get_allowed_caps (src->vidsrc);
GST_DEBUG_OBJECT (src, "Video src caps %" GST_PTR_FORMAT, caps);
src->video_renegotiate = FALSE;
g_mutex_unlock (&camerasrc->capturing_mutex);
gst_wrapper_camera_bin_reset_video_src_caps (src, caps);
g_mutex_lock (&camerasrc->capturing_mutex);
gst_caps_unref (caps);
gst_caps_unref (anycaps);
}
if (src->video_rec_status == GST_VIDEO_RECORDING_STATUS_DONE) {
src->video_rec_status = GST_VIDEO_RECORDING_STATUS_STARTING;
}
} else {
g_assert_not_reached ();
return FALSE;
}
return TRUE;
}
static void
gst_wrapper_camera_bin_src_stop_capture (GstBaseCameraSrc * camerasrc)
{
GstWrapperCameraBinSrc *src = GST_WRAPPER_CAMERA_BIN_SRC (camerasrc);
/* TODO shoud we access this directly? Maybe a macro is better? */
if (src->mode == MODE_VIDEO) {
if (src->video_rec_status == GST_VIDEO_RECORDING_STATUS_STARTING) {
GST_DEBUG_OBJECT (src, "Aborting, had not started recording");
src->video_rec_status = GST_VIDEO_RECORDING_STATUS_DONE;
} else if (src->video_rec_status == GST_VIDEO_RECORDING_STATUS_RUNNING) {
GST_DEBUG_OBJECT (src, "Marking video recording as finishing");
src->video_rec_status = GST_VIDEO_RECORDING_STATUS_FINISHING;
}
} else {
src->image_capture_count = 0;
}
}
static GstStateChangeReturn
gst_wrapper_camera_bin_src_change_state (GstElement * element,
GstStateChange trans)
{
GstStateChangeReturn ret;
GstWrapperCameraBinSrc *self = GST_WRAPPER_CAMERA_BIN_SRC (element);
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, trans);
if (ret == GST_STATE_CHANGE_FAILURE)
goto end;
switch (trans) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
self->video_renegotiate = TRUE;
self->image_renegotiate = TRUE;
self->drop_newseg = FALSE;
break;
case GST_STATE_CHANGE_READY_TO_NULL:
break;
case GST_STATE_CHANGE_NULL_TO_READY:
break;
default:
break;
}
end:
return ret;
}
static void
gst_wrapper_camera_bin_src_class_init (GstWrapperCameraBinSrcClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstBaseCameraSrcClass *gstbasecamerasrc_class;
gobject_class = G_OBJECT_CLASS (klass);
gstelement_class = GST_ELEMENT_CLASS (klass);
gstbasecamerasrc_class = GST_BASE_CAMERA_SRC_CLASS (klass);
gobject_class->dispose = gst_wrapper_camera_bin_src_dispose;
gobject_class->finalize =
(GObjectFinalizeFunc) gst_wrapper_camera_bin_src_finalize;
gobject_class->set_property = gst_wrapper_camera_bin_src_set_property;
gobject_class->get_property = gst_wrapper_camera_bin_src_get_property;
/* g_object_class_install_property .... */
g_object_class_install_property (gobject_class, PROP_VIDEO_SRC,
g_param_spec_object ("video-source", "Video source",
"The video source element to be used",
GST_TYPE_ELEMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_VIDEO_SRC_FILTER,
g_param_spec_object ("video-source-filter", "Video source filter",
"Optional video source filter element",
GST_TYPE_ELEMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstelement_class->change_state = gst_wrapper_camera_bin_src_change_state;
gstbasecamerasrc_class->construct_pipeline =
gst_wrapper_camera_bin_src_construct_pipeline;
gstbasecamerasrc_class->set_zoom = gst_wrapper_camera_bin_src_set_zoom;
gstbasecamerasrc_class->set_mode = gst_wrapper_camera_bin_src_set_mode;
gstbasecamerasrc_class->start_capture =
gst_wrapper_camera_bin_src_start_capture;
gstbasecamerasrc_class->stop_capture =
gst_wrapper_camera_bin_src_stop_capture;
GST_DEBUG_CATEGORY_INIT (wrapper_camera_bin_src_debug, "wrappercamerabinsrc",
0, "wrapper camera src");
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&vfsrc_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&imgsrc_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&vidsrc_template));
gst_element_class_set_static_metadata (gstelement_class,
"Wrapper camera src element for camerabin2", "Source/Video",
"Wrapper camera src element for camerabin2",
"Thiago Santos <thiago.sousa.santos@collabora.com>");
}
static void
gst_wrapper_camera_bin_src_init (GstWrapperCameraBinSrc * self)
{
self->vfsrc =
gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_VIEWFINDER_PAD_NAME,
GST_PAD_SRC);
gst_element_add_pad (GST_ELEMENT (self), self->vfsrc);
self->imgsrc =
gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_IMAGE_PAD_NAME,
GST_PAD_SRC);
gst_element_add_pad (GST_ELEMENT (self), self->imgsrc);
self->vidsrc =
gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_VIDEO_PAD_NAME,
GST_PAD_SRC);
gst_element_add_pad (GST_ELEMENT (self), self->vidsrc);
gst_pad_set_event_function (self->imgsrc,
GST_DEBUG_FUNCPTR (gst_wrapper_camera_bin_src_src_event));
gst_pad_set_event_function (self->vidsrc,
GST_DEBUG_FUNCPTR (gst_wrapper_camera_bin_src_src_event));
/* TODO where are variables reset? */
self->image_capture_count = 0;
self->video_rec_status = GST_VIDEO_RECORDING_STATUS_DONE;
self->video_renegotiate = TRUE;
self->image_renegotiate = TRUE;
self->mode = GST_BASE_CAMERA_SRC_CAST (self)->mode;
self->app_vid_filter = NULL;
}
gboolean
gst_wrapper_camera_bin_src_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "wrappercamerabinsrc", GST_RANK_NONE,
gst_wrapper_camera_bin_src_get_type ());
}
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