/* SPDX-License-Identifier: LGPL-2.1-or-later */ /* * Copyright (C) 2020, Collabora Ltd. * Author: Nicolas Dufresne * * gstlibcamerapool.cpp - GStreamer Buffer Pool */ #include "gstlibcamerapool.h" #include #include "gstlibcamera-utils.h" using namespace libcamera; enum { SIGNAL_BUFFER_NOTIFY, N_SIGNALS }; static guint signals[N_SIGNALS]; struct _GstLibcameraPool { GstBufferPool parent; GstAtomicQueue *queue; GstLibcameraAllocator *allocator; Stream *stream; }; G_DEFINE_TYPE(GstLibcameraPool, gst_libcamera_pool, GST_TYPE_BUFFER_POOL); static GstFlowReturn gst_libcamera_pool_acquire_buffer(GstBufferPool *pool, GstBuffer **buffer, GstBufferPoolAcquireParams *params) { GstLibcameraPool *self = GST_LIBCAMERA_POOL(pool); GstBuffer *buf = GST_BUFFER(gst_atomic_queue_pop(self->queue)); if (!buf) return GST_FLOW_ERROR; if (!gst_libcamera_allocator_prepare_buffer(self->allocator, self->stream, buf)) return GST_FLOW_ERROR; *buffer = buf; return GST_FLOW_OK; } static void gst_libcamera_pool_reset_buffer(GstBufferPool *pool, GstBuffer *buffer) { GstBufferPoolClass *klass = GST_BUFFER_POOL_CLASS(gst_libcamera_pool_parent_class); /* Clears all the memories and only pool the GstBuffer objects */ gst_buffer_remove_all_memory(buffer); klass->reset_buffer(pool, buffer); GST_BUFFER_FLAGS(buffer) = 0; } static void gst_libcamera_pool_release_buffer(GstBufferPool *pool, GstBuffer *buffer) { GstLibcameraPool *self = GST_LIBCAMERA_POOL(pool); bool do_notify = gst_atomic_queue_length(self->queue) == 0; gst_atomic_queue_push(self->queue, buffer); if (do_notify) g_signal_emit(self, signals[SIGNAL_BUFFER_NOTIFY], 0); } static void gst_libcamera_pool_init(GstLibcameraPool *self) { self->queue = gst_atomic_queue_new(4); } static void gst_libcamera_pool_finalize(GObject *object) { GstLibcameraPool *self = GST_LIBCAMERA_POOL(object); GstBuffer *buf; while ((buf = GST_BUFFER(gst_atomic_queue_pop(self->queue)))) gst_buffer_unref(buf); gst_atomic_queue_unref(self->queue); g_object_unref(self->allocator); G_OBJECT_CLASS(gst_libcamera_pool_parent_class)->finalize(object); } static void gst_libcamera_pool_class_init(GstLibcameraPoolClass *klass) { auto *object_class = G_OBJECT_CLASS(klass); auto *pool_class = GST_BUFFER_POOL_CLASS(klass); object_class->finalize = gst_libcamera_pool_finalize; pool_class->start = nullptr; pool_class->acquire_buffer = gst_libcamera_pool_acquire_buffer; pool_class->reset_buffer = gst_libcamera_pool_reset_buffer; pool_class->release_buffer = gst_libcamera_pool_release_buffer; signals[SIGNAL_BUFFER_NOTIFY] = g_signal_new("buffer-notify", G_OBJECT_CLASS_TYPE(klass), G_SIGNAL_RUN_LAST, 0, nullptr, nullptr, nullptr, G_TYPE_NONE, 0); } GstLibcameraPool * gst_libcamera_pool_new(GstLibcameraAllocator *allocator, Stream *stream) { auto *pool = GST_LIBCAMERA_POOL(g_object_new(GST_TYPE_LIBCAMERA_POOL, nullptr)); pool->allocator = GST_LIBCAMERA_ALLOCATOR(g_object_ref(allocator)); pool->stream = stream; gsize pool_size = gst_libcamera_allocator_get_pool_size(allocator, stream); for (gsize i = 0; i < pool_size; i++) { GstBuffer *buffer = gst_buffer_new(); gst_atomic_queue_push(pool->queue, buffer); } return pool; } Stream * gst_libcamera_pool_get_stream(GstLibcameraPool *self) { return self->stream; } Stream * gst_libcamera_buffer_get_stream(GstBuffer *buffer) { auto *self = (GstLibcameraPool *)buffer->pool; return self->stream; } FrameBuffer * gst_libcamera_buffer_get_frame_buffer(GstBuffer *buffer) { GstMemory *mem = gst_buffer_peek_memory(buffer, 0); return gst_libcamera_memory_get_frame_buffer(mem); } #n18'>18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654

/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Collabora Ltd.
 *     Author: Nicolas Dufresne <nicolas.dufresne@collabora.com>
 *
 * gstlibcamerasrc.cpp - 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 send EOS
 *    + Allowing application to use FLUSH/FLUSH_STOP
 *    + Prevent the main thread from accessing streaming thread
 *  - Implement renegotiation (even if slow)
 *  - 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)
 *
 * \todo libcamera UVC drivers picks the lowest possible resolution first, this
 * should be fixed so that we get a decent resolution and framerate for the
 * role by default.
 */

#include "gstlibcamerasrc.h"

#include <queue>
#include <vector>

#include <gst/base/base.h>

#include <libcamera/camera.h>
#include <libcamera/camera_manager.h>

#include "gstlibcameraallocator.h"
#include "gstlibcamerapad.h"
#include "gstlibcamerapool.h"
#include "gstlibcamera-utils.h"

using namespace libcamera;

GST_DEBUG_CATEGORY_STATIC(source_debug);
#define GST_CAT_DEFAULT source_debug

struct RequestWrap {
	RequestWrap(Request *request);
	~RequestWrap();

	void attachBuffer(GstBuffer *buffer);
	GstBuffer *detachBuffer(Stream *stream);

	/* For ptr comparison only. */
	Request *request_;
	std::map<Stream *, GstBuffer *> buffers_;
};

RequestWrap::RequestWrap(Request *request)
	: request_(request)
{
}

RequestWrap::~RequestWrap()
{
	for (std::pair<Stream *const, GstBuffer *> &item : buffers_) {
		if (item.second)
			gst_buffer_unref(item.second);
	}
}

void RequestWrap::attachBuffer(GstBuffer *buffer)
{
	FrameBuffer *fb = gst_libcamera_buffer_get_frame_buffer(buffer);
	Stream *stream = gst_libcamera_buffer_get_stream(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::unique_ptr<CameraManager> cm_;
	std::shared_ptr<Camera> cam_;
	std::unique_ptr<CameraConfiguration> config_;
	std::vector<GstPad *> srcpads_;
	std::queue<std::unique_ptr<RequestWrap>> requests_;

	void requestCompleted(Request *request);
};

struct _GstLibcameraSrc {
	GstElement parent;

	GRecMutex stream_lock;
	GstTask *task;

	gchar *camera_name;

	GstLibcameraSrcState *state;
	GstLibcameraAllocator *allocator;
	GstFlowCombiner *flow_combiner;
};

enum {
	PROP_0,
	PROP_CAMERA_NAME
};

G_DEFINE_TYPE_WITH_CODE(GstLibcameraSrc, gst_libcamera_src, GST_TYPE_ELEMENT,
			GST_DEBUG_CATEGORY_INIT(source_debug, "libcamerasrc", 0,
						"libcamera Source"));

#define TEMPLATE_CAPS GST_STATIC_CAPS("video/x-raw; image/jpeg")

/* 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_%s", GST_PAD_SRC, GST_PAD_REQUEST, TEMPLATE_CAPS
};

void
GstLibcameraSrcState::requestCompleted(Request *request)
{
	GLibLocker lock(GST_OBJECT(src_));

	GST_DEBUG_OBJECT(src_, "buffers are ready");

	std::unique_ptr<RequestWrap> wrap = std::move(requests_.front());
	requests_.pop();

	g_return_if_fail(wrap->request_ == request);

	if ((request->status() == Request::RequestCancelled)) {
		GST_DEBUG_OBJECT(src_, "Request was cancelled");
		return;
	}

	GstBuffer *buffer;
	for (GstPad *srcpad : srcpads_) {
		Stream *stream = gst_libcamera_pad_get_stream(srcpad);
		buffer = wrap->detachBuffer(stream);

		FrameBuffer *fb = gst_libcamera_buffer_get_frame_buffer(buffer);

		if (GST_ELEMENT_CLOCK(src_)) {
			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);
			GST_BUFFER_PTS(buffer) = fb->metadata().timestamp - sys_base_time;
			gst_libcamera_pad_set_latency(srcpad, sys_now - fb->metadata().timestamp);
		} else {
			GST_BUFFER_PTS(buffer) = 0;
		}

		GST_BUFFER_OFFSET(buffer) = fb->metadata().sequence;
		GST_BUFFER_OFFSET_END(buffer) = fb->metadata().sequence;

		gst_libcamera_pad_queue_buffer(srcpad, buffer);
	}

	gst_libcamera_resume_task(this->src_->task);
}

static bool
gst_libcamera_src_open(GstLibcameraSrc *self)
{
	std::unique_ptr<CameraManager> cm = std::make_unique<CameraManager>();
	std::shared_ptr<Camera> cam;
	gint ret = 0;

	GST_DEBUG_OBJECT(self, "Opening camera device ...");

	ret = cm->start();
	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(self->camera_name);
		if (!cam) {
			GST_ELEMENT_ERROR(self, RESOURCE, NOT_FOUND,
					  ("Could not find a camera named '%s'.", self->camera_name),
					  ("libcamera::CameraMananger::get() returned nullptr"));
			return false;
		}
	} else {
		if (cm->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 = cm->cameras()[0];
	}

	GST_INFO_OBJECT(self, "Using camera named '%s'", cam->name().c_str());

	ret = cam->acquire();
	if (ret) {
		GST_ELEMENT_ERROR(self, RESOURCE, BUSY,
				  ("Camera name '%s' is already in use.", cam->name().c_str()),
				  ("libcamera::Camera::acquire() failed: %s", g_strerror(ret)));
		return false;
	}

	cam->requestCompleted.connect(self->state, &GstLibcameraSrcState::requestCompleted);

	/* No need to lock here, we didn't start our threads yet. */
	self->state->cm_ = std::move(cm);
	self->state->cam_ = cam;

	return true;
}

static void
gst_libcamera_src_task_run(gpointer user_data)
{
	GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);
	GstLibcameraSrcState *state = self->state;

	Request *request = state->cam_->createRequest();
	auto wrap = std::make_unique<RequestWrap>(request);
	for (GstPad *srcpad : state->srcpads_) {
		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 does not take ownership, and we won't be
			 * queueing this one due to lack of buffers.
			 */
			delete request;
			request = nullptr;
			break;
		}

		wrap->attachBuffer(buffer);
	}

	if (request) {
		GLibLocker lock(GST_OBJECT(self));
		GST_TRACE_OBJECT(self, "Requesting buffers");
		state->cam_->queueRequest(request);
		state->requests_.push(std::move(wrap));
	}

	GstFlowReturn ret = GST_FLOW_OK;
	gst_flow_combiner_reset(self->flow_combiner);
	for (GstPad *srcpad : state->srcpads_) {
		ret = gst_libcamera_pad_push_pending(srcpad);
		ret = gst_flow_combiner_update_pad_flow(self->flow_combiner,
							srcpad, ret);
	}

	{
		/*
		 * Here we need to decide if we want to pause or stop the task. This
		 * needs to happen in lock step with the callback thread which may want
		 * to resume the task.
		 */
		GLibLocker lock(GST_OBJECT(self));
		if (ret != GST_FLOW_OK) {
			if (ret == 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 : state->srcpads_)
					gst_pad_push_event(srcpad, gst_event_ref(eos));
			} else if (ret != GST_FLOW_FLUSHING) {
				GST_ELEMENT_FLOW_ERROR(self, ret);
			}
			gst_task_stop(self->task);
			return;
		}

		bool do_pause = true;
		for (GstPad *srcpad : state->srcpads_) {
			if (gst_libcamera_pad_has_pending(srcpad)) {
				do_pause = false;
				break;
			}
		}

		if (do_pause)
			gst_task_pause(self->task);
	}
}

static void
gst_libcamera_src_task_enter(GstTask *task, GThread *thread, gpointer user_data)
{
	GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);
	GLibRecLocker lock(&self->stream_lock);
	GstLibcameraSrcState *state = self->state;
	GstFlowReturn flow_ret = GST_FLOW_OK;
	gint ret;

	GST_DEBUG_OBJECT(self, "Streaming thread has started");

	guint group_id = gst_util_group_id_next();
	StreamRoles roles;
	for (GstPad *srcpad : state->srcpads_) {
		/* Create stream-id and push stream-start. */
		g_autofree gchar *stream_id = gst_pad_create_stream_id(srcpad, GST_ELEMENT(self), nullptr);
		GstEvent *event = gst_event_new_stream_start(stream_id);
		gst_event_set_group_id(event, 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);
	/*
	 * \todo Check if camera may increase or decrease the number of streams
	 * regardless of the number of roles.
	 */
	g_assert(state->config_->size() == state->srcpads_.size());

	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)) {
			flow_ret = GST_FLOW_NOT_NEGOTIATED;
			break;
		}

		/* Fixate caps and configure the stream. */
		caps = gst_caps_make_writable(caps);
		gst_libcamera_configure_stream_from_caps(stream_cfg, caps);
	}

	if (flow_ret != GST_FLOW_OK)
		goto done;

	/* Validate the configuration. */
	if (state->config_->validate() == CameraConfiguration::Invalid) {
		flow_ret = GST_FLOW_NOT_NEGOTIATED;
		goto done;
	}

	/*
	 * 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);
		if (!gst_pad_push_event(srcpad, gst_event_new_caps(caps))) {
			flow_ret = GST_FLOW_NOT_NEGOTIATED;
			break;
		}

		/* 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_->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));
		gst_task_stop(task);
		return;
	}

	self->allocator = gst_libcamera_allocator_new(state->cam_);
	if (!self->allocator) {
		GST_ELEMENT_ERROR(self, RESOURCE, NO_SPACE_LEFT,
				  ("Failed to allocate memory"),
				  ("gst_libcamera_allocator_new() failed."));
		gst_task_stop(task);
		return;
	}

	self->flow_combiner = gst_flow_combiner_new();
	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_libcamera_resume_task), task);

		gst_libcamera_pad_set_pool(srcpad, pool);
		gst_flow_combiner_add_pad(self->flow_combiner, srcpad);
	}

	ret = state->cam_->start();
	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;
	}

done:
	switch (flow_ret) {
	case GST_FLOW_NOT_NEGOTIATED:
		GST_ELEMENT_FLOW_ERROR(self, flow_ret);
		gst_task_stop(task);
		break;
	default:
		break;
	}
}

static void
gst_libcamera_src_task_leave(GstTask *task, GThread *thread, gpointer user_data)
{
	GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data);