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|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2019, Collabora Ltd.
* Author: Nicolas Dufresne <nicolas.dufresne@collabora.com>
*
* GStreamer Capture Element
*/
/**
* \todo The following is a list of items that needs implementation in the GStreamer plugin
* - Implement GstElement::send_event
* + Allowing application to use FLUSH/FLUSH_STOP
* + Prevent the main thread from accessing streaming thread
* - Implement GstElement::request-new-pad (multi stream)
* + Evaluate if a single streaming thread is fine
* - Add application driven request (snapshot)
* - Add framerate control
* - Add buffer importation support
*
* Requires new libcamera API:
* - Add framerate negotiation support
* - Add colorimetry support
* - Add timestamp support
* - Use unique names to select the camera devices
* - Add GstVideoMeta support (strides and offsets)
*/
#include "gstlibcamerasrc.h"
#include <atomic>
#include <queue>
#include <vector>
#include <libcamera/camera.h>
#include <libcamera/camera_manager.h>
#include <libcamera/control_ids.h>
#include <gst/base/base.h>
#include "gstlibcamera-controls.h"
#include "gstlibcamera-utils.h"
#include "gstlibcameraallocator.h"
#include "gstlibcamerapad.h"
#include "gstlibcamerapool.h"
using namespace libcamera;
GST_DEBUG_CATEGORY_STATIC(source_debug);
#define GST_CAT_DEFAULT source_debug
struct RequestWrap {
RequestWrap(std::unique_ptr<Request> request);
~RequestWrap();
void attachBuffer(Stream *stream, GstBuffer *buffer);
GstBuffer *detachBuffer(Stream *stream);
std::unique_ptr<Request> request_;
std::map<Stream *, GstBuffer *> buffers_;
GstClockTime latency_;
GstClockTime pts_;
};
RequestWrap::RequestWrap(std::unique_ptr<Request> request)
: request_(std::move(request)), latency_(0), pts_(GST_CLOCK_TIME_NONE)
{
}
RequestWrap::~RequestWrap()
{
for (std::pair<Stream *const, GstBuffer *> &item : buffers_) {
if (item.second)
gst_buffer_unref(item.second);
}
}
void RequestWrap::attachBuffer(Stream *stream, GstBuffer *buffer)
{
FrameBuffer *fb = gst_libcamera_buffer_get_frame_buffer(buffer);
request_->addBuffer(stream, fb);
auto item = buffers_.find(stream);
if (item != buffers_.end()) {
gst_buffer_unref(item->second);
item->second = buffer;
} else {
buffers_[stream] = buffer;
}
}
GstBuffer *RequestWrap::detachBuffer(Stream *stream)
{
GstBuffer *buffer = nullptr;
auto item = buffers_.find(stream);
if (item != buffers_.end()) {
buffer = item->second;
item->second = nullptr;
}
return buffer;
}
/* Used for C++ object with destructors. */
struct GstLibcameraSrcState {
GstLibcameraSrc *src_;
std::shared_ptr<CameraManager> cm_;
std::shared_ptr<Camera> cam_;
std::unique_ptr<CameraConfiguration> config_;
std::vector<GstPad *> srcpads_; /* Protected by stream_lock */
/*
* Contention on this lock_ must be minimized, as it has to be taken in
* the realtime-sensitive requestCompleted() handler to protect
* queuedRequests_ and completedRequests_.
*
* stream_lock must be taken before lock_ in contexts where both locks
* need to be taken. In particular, this means that the lock_ must not
* be held while calling into other graph elements (e.g. when calling
* gst_pad_query()).
*/
GMutex lock_;
std::queue<std::unique_ptr<RequestWrap>> queuedRequests_;
std::queue<std::unique_ptr<RequestWrap>> completedRequests_;
ControlList initControls_;
guint group_id_;
GstCameraControls controls_;
int queueRequest();
void requestCompleted(Request *request);
int processRequest();
void clearRequests();
};
struct _GstLibcameraSrc {
GstElement parent;
GRecMutex stream_lock;
GstTask *task;
gchar *camera_name;
std::atomic<GstEvent *> pending_eos;
GstLibcameraSrcState *state;
GstLibcameraAllocator *allocator;
GstFlowCombiner *flow_combiner;
};
enum {
PROP_0,
PROP_CAMERA_NAME,
PROP_LAST
};
static void gst_libcamera_src_child_proxy_init(gpointer g_iface,
gpointer iface_data);
G_DEFINE_TYPE_WITH_CODE(GstLibcameraSrc, gst_libcamera_src, GST_TYPE_ELEMENT,
G_IMPLEMENT_INTERFACE(GST_TYPE_CHILD_PROXY,
gst_libcamera_src_child_proxy_init)
GST_DEBUG_CATEGORY_INIT(source_debug, "libcamerasrc", 0,
"libcamera Source"))
#define TEMPLATE_CAPS GST_STATIC_CAPS("video/x-raw; image/jpeg; video/x-bayer")
/* For the simple case, we have a src pad that is always present. */
GstStaticPadTemplate src_template = {
"src", GST_PAD_SRC, GST_PAD_ALWAYS, TEMPLATE_CAPS
};
/* More pads can be requested in state < PAUSED */
GstStaticPadTemplate request_src_template = {
"src_%u", GST_PAD_SRC, GST_PAD_REQUEST, TEMPLATE_CAPS
};
/* Must be called with stream_lock held. */
int GstLibcameraSrcState::queueRequest()
{
std::unique_ptr<Request> request = cam_->createRequest();
if (!request)
return -ENOMEM;
/* Apply controls */
controls_.applyControls(request);
std::unique_ptr<RequestWrap> wrap =
std::make_unique<RequestWrap>(std::move(request));
for (GstPad *srcpad : srcpads_) {
Stream *stream = gst_libcamera_pad_get_stream(srcpad);
GstLibcameraPool *pool = gst_libcamera_pad_get_pool(srcpad);
GstBuffer *buffer;
GstFlowReturn ret;
ret = gst_buffer_pool_acquire_buffer(GST_BUFFER_POOL(pool),
&buffer, nullptr);
if (ret != GST_FLOW_OK) {
/*
* RequestWrap has ownership of the request, and we
* won't be queueing this one due to lack of buffers.
*/
return -ENOBUFS;
}
wrap->attachBuffer(stream, buffer);
}
GST_TRACE_OBJECT(src_, "Requesting buffers");
cam_->queueRequest(wrap->request_.get());
{
GLibLocker locker(&lock_);
queuedRequests_.push(std::move(wrap));
}
/* The RequestWrap will be deleted in the completion handler. */
return 0;
}
void
GstLibcameraSrcState::requestCompleted(Request *request)
{
GST_DEBUG_OBJECT(src_, "buffers are ready");
std::unique_ptr<RequestWrap> wrap;
{
GLibLocker locker(&lock_);
controls_.readMetadata(request);
wrap = std::move(queuedRequests_.front());
queuedRequests_.pop();
}
g_return_if_fail(wrap->request_.get() == request);
if ((request->status() == Request::RequestCancelled)) {
GST_DEBUG_OBJECT(src_, "Request was cancelled");
return;
}
if (GST_ELEMENT_CLOCK(src_)) {
int64_t timestamp = request->metadata().get(controls::SensorTimestamp).value_or(0);
GstClockTime gst_base_time = GST_ELEMENT(src_)->base_time;
GstClockTime gst_now = gst_clock_get_time(GST_ELEMENT_CLOCK(src_));
/* \todo Need to expose which reference clock the timestamp relates to. */
GstClockTime sys_now = g_get_monotonic_time() * 1000;
/* Deduced from: sys_now - sys_base_time == gst_now - gst_base_time */
GstClockTime sys_base_time = sys_now - (gst_now - gst_base_time);
wrap->pts_ = timestamp - sys_base_time;
wrap->latency_ = sys_now - timestamp;
}
{
GLibLocker locker(&lock_);
completedRequests_.push(std::move(wrap));
}
gst_task_resume(src_->task);
}
/* Must be called with stream_lock held. */
int GstLibcameraSrcState::processRequest()
{
std::unique_ptr<RequestWrap> wrap;
int err = 0;
{
GLibLocker locker(&lock_);
if (!completedRequests_.empty()) {
wrap = std::move(completedRequests_.front());
completedRequests_.pop();
}
if (completedRequests_.empty())
err = -ENOBUFS;
}
if (!wrap)
return -ENOBUFS;
GstFlowReturn ret = GST_FLOW_OK;
gst_flow_combiner_reset(src_->flow_combiner);
for (GstPad *srcpad : srcpads_) {
Stream *stream = gst_libcamera_pad_get_stream(srcpad);
GstBuffer *buffer = wrap->detachBuffer(stream);
FrameBuffer *fb = gst_libcamera_buffer_get_frame_buffer(buffer);
if (GST_CLOCK_TIME_IS_VALID(wrap->pts_)) {
GST_BUFFER_PTS(buffer) = wrap->pts_;
gst_libcamera_pad_set_latency(srcpad, wrap->latency_);
} else {
GST_BUFFER_PTS(buffer) = 0;
}
GST_BUFFER_OFFSET(buffer) = fb->metadata().sequence;
GST_BUFFER_OFFSET_END(buffer) = fb->metadata().sequence;
ret = gst_pad_push(srcpad, buffer);
ret = gst_flow_combiner_update_pad_flow(src_->flow_combiner,
srcpad, ret);
}
switch (ret) {
case GST_FLOW_OK:
break;
case GST_FLOW_NOT_NEGOTIATED: {
bool reconfigure = false;
for (GstPad *srcpad : srcpads_) {
if (gst_pad_needs_reconfigure(srcpad)) {
reconfigure = true;
break;
}
}
/* If no pads need a reconfiguration something went wrong. */
if (!reconfigure)
err = -EPIPE;
break;
}
case GST_FLOW_EOS: {
g_autoptr(GstEvent) eos = gst_event_new_eos();
guint32 seqnum = gst_util_seqnum_next();
gst_event_set_seqnum(eos, seqnum);
for (GstPad *srcpad : srcpads_)
gst_pad_push_event(srcpad, gst_event_ref(eos));
err = -EPIPE;
break;
}
case GST_FLOW_FLUSHING:
err = -EPIPE;
break;
default:
GST_ELEMENT_FLOW_ERROR(src_, ret);
err = -EPIPE;
break;
}
return err;
}
void GstLibcameraSrcState::clearRequests()
{
GLibLocker locker(&lock_);
completedRequests_ = {};
}
static bool
gst_libcamera_src_open(GstLibcameraSrc *self)
{
std::shared_ptr<CameraManager> cm;
std::shared_ptr<Camera> cam;
gint ret;
GST_DEBUG_OBJECT(self, "Opening camera device ...");
cm = gst_libcamera_get_camera_manager(ret);
if (ret) {
GST_ELEMENT_ERROR(self, LIBRARY, INIT,
("Failed listing cameras."),
("libcamera::CameraMananger::start() failed: %s", g_strerror(-ret)));
return false;
}
g_autofree gchar *camera_name = nullptr;
{
GLibLocker lock(GST_OBJECT(self));
if (self->camera_name)
camera_name = g_strdup(self->camera_name);
}
if (camera_name) {
cam = cm->get(camera_name);
if (!cam) {
GST_ELEMENT_ERROR(self, RESOURCE, NOT_FOUND,
("Could not find a camera named '%s'.", camera_name),
("libcamera::CameraMananger::get() returned nullptr"));
return false;
}
} else {
auto cameras = cm->cameras();
if (cameras.empty()) {
GST_ELEMENT_ERROR(self, RESOURCE, NOT_FOUND,
("Could not find any supported camera on this system."),
("libcamera::CameraMananger::cameras() is empty"));
return false;
}
cam = cameras[0];
}
GST_INFO_OBJECT(self, "Using camera '%s'", cam->id().c_str());
ret = cam->acquire();
if (ret) {
GST_ELEMENT_ERROR(self, RESOURCE, BUSY,
("Camera '%s' is already in use.", cam->id().c_str()),
("libcamera::Camera::acquire() failed: %s", g_strerror(ret)));
return false;
}
self->state->controls_.setCamera(cam);
cam->requestCompleted.connect(self->state, &GstLibcameraSrcState::requestCompleted);
/* No need to lock here, we didn't start our threads yet. */
self->state->cm_ = cm;
self->state->cam_ = cam;
return true;
}
/* Must be called with stream_lock held. */
static bool
gst_libcamera_src_negotiate(GstLibcameraSrc *self)
{
GstLibcameraSrcState *state = self->state;
std::vector<GstVideoTransferFunction> transfer(state->srcpads_.size(),
GST_VIDEO_TRANSFER_UNKNOWN);
g_autoptr(GstStructure) element_caps = gst_structure_new_empty("caps");
for (gsize i = 0; i < state->srcpads_.size(); i++) {
GstPad *srcpad = state->srcpads_[i];
StreamConfiguration &stream_cfg = state->config_->at(i);
/* Retrieve the supported caps. */
g_autoptr(GstCaps) filter = gst_libcamera_stream_formats_to_caps(stream_cfg.formats());
g_autoptr(GstCaps) caps = gst_pad_peer_query_caps(srcpad, filter);
if (gst_caps_is_empty(caps))
return false;
/* Fixate caps and configure the stream. */
caps = gst_caps_make_writable(caps);
gst_libcamera_configure_stream_from_caps(stream_cfg, caps, &transfer[i]);
gst_libcamera_get_framerate_from_caps(caps, element_caps);
}
/* Validate the configuration. */
if (state->config_->validate() == CameraConfiguration::Invalid)
return false;
int ret = state->cam_->configure(state->config_.get());
if (ret) {
GST_ELEMENT_ERROR(self, RESOURCE, SETTINGS,
("Failed to configure camera: %s", g_strerror(-ret)),
("Camera::configure() failed with error code %i", ret));
return false;
}
/* Check frame duration bounds within controls::FrameDurationLimits */
gst_libcamera_clamp_and_set_frameduration(state->initControls_,
state->cam_->controls(), element_caps);
/*
* Regardless if it has been modified, create clean caps and push the
* caps event. Downstream will decide if the caps are acceptable.
*/
for (gsize i = 0; i < state->srcpads_.size(); i++) {
GstPad *srcpad = state->srcpads_[i];
const StreamConfiguration &stream_cfg = state->config_->at(i);
g_autoptr(GstCaps) caps = gst_libcamera_stream_configuration_to_caps(stream_cfg, transfer[i]);
gst_libcamera_framerate_to_caps(caps, element_caps);
if (!gst_pad_push_event(srcpad, gst_event_new_caps(caps)))
return false;
}
if (self->allocator)
g_clear_object(&self->allocator);
self->allocator = gst_libcamera_allocator_new(state->cam_, state->config_.get());
if (!self->allocator) {
GST_ELEMENT_ERROR(self, RESOURCE, NO_SPACE_LEFT,
("Failed to allocate memory"),
("gst_libcamera_allocator_new() failed."));
return false;
}
for (gsize i = 0; i < state->srcpads_.size(); i++) {
GstPad *srcpad = state->srcpads_[i];
const StreamConfiguration &stream_cfg = state->config_->at(i);
GstLibcameraPool *pool = gst_libcamera_pool_new(self->allocator,
stream_cfg.stream());
g_signal_connect_swapped(pool, "buffer-notify",
G_CALLBACK(gst_task_resume), self->task);
gst_libcamera_pad_set_pool(srcpad, pool);
/* Clear all reconfigure flags. */
gst_pad_check_reconfigure(srcpad);
}
return true;
}
static void
gst_libcamera_src_task_run(gpointer user_data)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);
GstLibcameraSrcState *state = self->state;
/*
* Start by pausing the task. The task may also get resumed by the
* buffer-notify signal when new buffers are queued back to the pool,
* or by the request completion handler when a new request has
* completed. Both will resume the task after adding the buffers or
* request to their respective lists, which are checked below to decide
* if the task needs to be resumed for another iteration. This is thus
* guaranteed to be race-free, the lock taken by gst_task_pause() and
* gst_task_resume() serves as a memory barrier.
*/
gst_task_pause(self->task);
bool doResume = false;
g_autoptr(GstEvent) event = self->pending_eos.exchange(nullptr);
if (event) {
for (GstPad *srcpad : state->srcpads_)
gst_pad_push_event(srcpad, gst_event_ref(event));
return;
}
/* Check if a srcpad requested a renegotiation. */
bool reconfigure = false;
for (GstPad *srcpad : state->srcpads_) {
if (gst_pad_check_reconfigure(srcpad)) {
/* Check if the caps even need changing. */
g_autoptr(GstCaps) caps = gst_pad_get_current_caps(srcpad);
if (!gst_pad_peer_query_accept_caps(srcpad, caps)) {
reconfigure = true;
break;
}
}
}
if (reconfigure) {
state->cam_->stop();
state->clearRequests();
if (!gst_libcamera_src_negotiate(self)) {
GST_ELEMENT_FLOW_ERROR(self, GST_FLOW_NOT_NEGOTIATED);
gst_task_stop(self->task);
}
state->cam_->start(&state->initControls_);
}
/*
* Create and queue one request. If no buffers are available the
* function returns -ENOBUFS, which we ignore here as that's not a
* fatal error.
*/
int ret = state->queueRequest();
switch (ret) {
case 0:
/*
* The request was successfully queued, there may be enough
* buffers to create a new one. Don't pause the task to give it
* another try.
*/
doResume = true;
break;
case -ENOMEM:
GST_ELEMENT_ERROR(self, RESOURCE, NO_SPACE_LEFT,
("Failed to allocate request for camera '%s'.",
state->cam_->id().c_str()),
("libcamera::Camera::createRequest() failed"));
gst_task_stop(self->task);
return;
case -ENOBUFS:
default:
break;
}
/*
* Process one completed request, if available, and record if further
* requests are ready for processing.
*/
ret = state->processRequest();
switch (ret) {
case 0:
/* Another completed request is available, resume the task. */
doResume = true;
break;
case -EPIPE:
gst_task_stop(self->task);
return;
case -ENOBUFS:
default:
break;
}
/* Resume the task for another iteration if needed. */
if (doResume)
gst_task_resume(self->task);
}
static void
gst_libcamera_src_task_enter(GstTask *task, [[maybe_unused]] GThread *thread,
gpointer user_data)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);
GLibRecLocker lock(&self->stream_lock);
GstLibcameraSrcState *state = self->state;
gint ret;
GST_DEBUG_OBJECT(self, "Streaming thread has started");
gint stream_id_num = 0;
std::vector<StreamRole> roles;
for (GstPad *srcpad : state->srcpads_) {
/* Create stream-id and push stream-start. */
g_autofree gchar *stream_id_intermediate = g_strdup_printf("%i%i", state->group_id_, stream_id_num++);
g_autofree gchar *stream_id = gst_pad_create_stream_id(srcpad, GST_ELEMENT(self), stream_id_intermediate);
GstEvent *event = gst_event_new_stream_start(stream_id);
gst_event_set_group_id(event, state->group_id_);
gst_pad_push_event(srcpad, event);
/* Collect the streams roles for the next iteration. */
roles.push_back(gst_libcamera_pad_get_role(srcpad));
}
/* Generate the stream configurations, there should be one per pad. */
state->config_ = state->cam_->generateConfiguration(roles);
if (state->config_ == nullptr) {
GST_ELEMENT_ERROR(self, RESOURCE, SETTINGS,
("Failed to generate camera configuration from roles"),
("Camera::generateConfiguration() returned nullptr"));
gst_task_stop(task);
return;
}
g_assert(state->config_->size() == state->srcpads_.size());
if (!gst_libcamera_src_negotiate(self)) {
state->initControls_.clear();
GST_ELEMENT_FLOW_ERROR(self, GST_FLOW_NOT_NEGOTIATED);
gst_task_stop(task);
return;
}
self->flow_combiner = gst_flow_combiner_new();
for (GstPad *srcpad : state->srcpads_) {
gst_flow_combiner_add_pad(self->flow_combiner, srcpad);
/* Send an open segment event with time format. */
GstSegment segment;
gst_segment_init(&segment, GST_FORMAT_TIME);
gst_pad_push_event(srcpad, gst_event_new_segment(&segment));
}
ret = state->cam_->start(&state->initControls_);
if (ret) {
GST_ELEMENT_ERROR(self, RESOURCE, SETTINGS,
("Failed to start the camera: %s", g_strerror(-ret)),
("Camera.start() failed with error code %i", ret));
gst_task_stop(task);
return;
}
}
static void
gst_libcamera_src_task_leave([[maybe_unused]] GstTask *task,
[[maybe_unused]] GThread *thread,
gpointer user_data)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);
GstLibcameraSrcState *state = self->state;
GST_DEBUG_OBJECT(self, "Streaming thread is about to stop");
state->cam_->stop();
state->clearRequests();
{
GLibRecLocker locker(&self->stream_lock);
for (GstPad *srcpad : state->srcpads_)
gst_libcamera_pad_set_pool(srcpad, nullptr);
}
g_clear_object(&self->allocator);
g_clear_pointer(&self->flow_combiner,
(GDestroyNotify)gst_flow_combiner_free);
}
static void
gst_libcamera_src_close(GstLibcameraSrc *self)
{
GstLibcameraSrcState *state = self->state;
gint ret;
GST_DEBUG_OBJECT(self, "Releasing resources");
state->config_.reset();
ret = state->cam_->release();
if (ret) {
GST_ELEMENT_WARNING(self, RESOURCE, BUSY,
("Camera '%s' is still in use.", state->cam_->id().c_str()),
("libcamera::Camera.release() failed: %s", g_strerror(-ret)));
}
state->cam_.reset();
state->cm_.reset();
}
static void
gst_libcamera_src_set_property(GObject *object, guint prop_id,
const GValue *value, GParamSpec *pspec)
{
GLibLocker lock(GST_OBJECT(object));
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(object);
GstLibcameraSrcState *state = self->state;
switch (prop_id) {
case PROP_CAMERA_NAME:
g_free(self->camera_name);
self->camera_name = g_value_dup_string(value);
break;
default:
if (!state->controls_.setProperty(prop_id - PROP_LAST, value, pspec))
G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
break;
}
}
static void
gst_libcamera_src_get_property(GObject *object, guint prop_id, GValue *value,
GParamSpec *pspec)
{
GLibLocker lock(GST_OBJECT(object));
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(object);
GstLibcameraSrcState *state = self->state;
switch (prop_id) {
case PROP_CAMERA_NAME:
g_value_set_string(value, self->camera_name);
break;
default:
if (!state->controls_.getProperty(prop_id - PROP_LAST, value, pspec))
G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_libcamera_src_change_state(GstElement *element, GstStateChange transition)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(element);
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstElementClass *klass = GST_ELEMENT_CLASS(gst_libcamera_src_parent_class);
ret = klass->change_state(element, transition);
if (ret == GST_STATE_CHANGE_FAILURE)
return ret;
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (!gst_libcamera_src_open(self))
return GST_STATE_CHANGE_FAILURE;
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
/* This needs to be called after pads activation.*/
self->state->group_id_ = gst_util_group_id_next();
if (!gst_task_pause(self->task))
return GST_STATE_CHANGE_FAILURE;
ret = GST_STATE_CHANGE_NO_PREROLL;
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
gst_task_start(self->task);
break;
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
ret = GST_STATE_CHANGE_NO_PREROLL;
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
/*
* \todo this might require some thread unblocking in the future
* if the streaming thread starts doing any kind of blocking
* operations. If this was the case, we would need to do so
* before pad deactivation, so before chaining to the parent
* change_state function.
*/
gst_task_join(self->task);
break;
case GST_STATE_CHANGE_READY_TO_NULL:
gst_libcamera_src_close(self);
break;
default:
break;
}
return ret;
}
static gboolean
gst_libcamera_src_send_event(GstElement *element, GstEvent *event)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(element);
gboolean ret = FALSE;
switch (GST_EVENT_TYPE(event)) {
case GST_EVENT_EOS: {
GstEvent *oldEvent = self->pending_eos.exchange(event);
gst_clear_event(&oldEvent);
ret = TRUE;
break;
}
default:
gst_event_unref(event);
break;
}
return ret;
}
static void
gst_libcamera_src_finalize(GObject *object)
{
GObjectClass *klass = G_OBJECT_CLASS(gst_libcamera_src_parent_class);
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(object);
g_rec_mutex_clear(&self->stream_lock);
g_clear_object(&self->task);
g_mutex_clear(&self->state->lock_);
g_free(self->camera_name);
delete self->state;
return klass->finalize(object);
}
static void
gst_libcamera_src_init(GstLibcameraSrc *self)
{
GstLibcameraSrcState *state = new GstLibcameraSrcState();
GstPadTemplate *templ = gst_element_get_pad_template(GST_ELEMENT(self), "src");
g_rec_mutex_init(&self->stream_lock);
self->task = gst_task_new(gst_libcamera_src_task_run, self, nullptr);
gst_task_set_enter_callback(self->task, gst_libcamera_src_task_enter, self, nullptr);
gst_task_set_leave_callback(self->task, gst_libcamera_src_task_leave, self, nullptr);
gst_task_set_lock(self->task, &self->stream_lock);
g_mutex_init(&state->lock_);
GstPad *pad = gst_pad_new_from_template(templ, "src");
state->srcpads_.push_back(pad);
gst_element_add_pad(GST_ELEMENT(self), pad);
gst_child_proxy_child_added(GST_CHILD_PROXY(self), G_OBJECT(pad), GST_OBJECT_NAME(pad));
GST_OBJECT_FLAG_SET(self, GST_ELEMENT_FLAG_SOURCE);
/* C-style friend. */
state->src_ = self;
self->state = state;
}
static GstPad *
gst_libcamera_src_request_new_pad(GstElement *element, GstPadTemplate *templ,
const gchar *name, [[maybe_unused]] const GstCaps *caps)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(element);
g_autoptr(GstPad) pad = NULL;
GST_DEBUG_OBJECT(self, "new request pad created");
pad = gst_pad_new_from_template(templ, name);
g_object_ref_sink(pad);
if (gst_element_add_pad(element, pad)) {
GLibRecLocker lock(&self->stream_lock);
self->state->srcpads_.push_back(reinterpret_cast<GstPad *>(g_object_ref(pad)));
} else {
GST_ELEMENT_ERROR(element, STREAM, FAILED,
("Internal data stream error."),
("Could not add pad to element"));
return NULL;
}
gst_child_proxy_child_added(GST_CHILD_PROXY(self), G_OBJECT(pad), GST_OBJECT_NAME(pad));
return reinterpret_cast<GstPad *>(g_steal_pointer(&pad));
}
static void
gst_libcamera_src_release_pad(GstElement *element, GstPad *pad)
{
GstLibcameraSrc *self = GST_LIBCAMERA_SRC(element);
gst_child_proxy_child_removed(GST_CHILD_PROXY(self), G_OBJECT(pad), GST_OBJECT_NAME(pad));
GST_DEBUG_OBJECT(self, "Pad %" GST_PTR_FORMAT " being released", pad);
{
GLibRecLocker lock(&self->stream_lock);
std::vector<GstPad *> &pads = self->state->srcpads_;
auto begin_iterator = pads.begin();
auto end_iterator = pads.end();
auto pad_iterator = std::find(begin_iterator, end_iterator, pad);
if (pad_iterator != end_iterator) {
g_object_unref(*pad_iterator);
pads.erase(pad_iterator);
}
}
gst_element_remove_pad(element, pad);
}
static void
gst_libcamera_src_class_init(GstLibcameraSrcClass *klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS(klass);
GObjectClass *object_class = G_OBJECT_CLASS(klass);
object_class->set_property = gst_libcamera_src_set_property;
object_class->get_property = gst_libcamera_src_get_property;
object_class->finalize = gst_libcamera_src_finalize;
element_class->request_new_pad = gst_libcamera_src_request_new_pad;
element_class->release_pad = gst_libcamera_src_release_pad;
element_class->change_state = gst_libcamera_src_change_state;
element_class->send_event = gst_libcamera_src_send_event;
gst_element_class_set_metadata(element_class,
"libcamera Source", "Source/Video",
"Linux Camera source using libcamera",
"Nicolas Dufresne <nicolas.dufresne@collabora.com>");
gst_element_class_add_static_pad_template_with_gtype(element_class,
&src_template,
GST_TYPE_LIBCAMERA_PAD);
gst_element_class_add_static_pad_template_with_gtype(element_class,
&request_src_template,
GST_TYPE_LIBCAMERA_PAD);
GParamSpec *spec = g_param_spec_string("camera-name", "Camera Name",
"Select by name which camera to use.", nullptr,
(GParamFlags)(GST_PARAM_MUTABLE_READY
| G_PARAM_CONSTRUCT
| G_PARAM_READWRITE
| G_PARAM_STATIC_STRINGS));
g_object_class_install_property(object_class, PROP_CAMERA_NAME, spec);
GstCameraControls::installProperties(object_class, PROP_LAST);
}
/* GstChildProxy implementation */
static GObject *
gst_libcamera_src_child_proxy_get_child_by_index(GstChildProxy *child_proxy,
guint index)
{
GLibLocker lock(GST_OBJECT(child_proxy));
GObject *obj = nullptr;
obj = reinterpret_cast<GObject *>(g_list_nth_data(GST_ELEMENT(child_proxy)->srcpads, index));
if (obj)
gst_object_ref(obj);
return obj;
}
static guint
gst_libcamera_src_child_proxy_get_children_count(GstChildProxy *child_proxy)
{
GLibLocker lock(GST_OBJECT(child_proxy));
return GST_ELEMENT_CAST(child_proxy)->numsrcpads;
}
static void
gst_libcamera_src_child_proxy_init(gpointer g_iface, [[maybe_unused]] gpointer iface_data)
{
GstChildProxyInterface *iface = reinterpret_cast<GstChildProxyInterface *>(g_iface);
iface->get_child_by_index = gst_libcamera_src_child_proxy_get_child_by_index;
iface->get_children_count = gst_libcamera_src_child_proxy_get_children_count;
}
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