[libcamera-devel] [RFC PATCH v2 4/5] android: camera_device: Add a queue for sending capture results
Umang Jain
umang.jain at ideasonboard.com
Thu Sep 2 23:31:27 CEST 2021
When a camera capture request completes, the next step is to send the
capture results to the framework via process_capture_results(). All
the capture associated result metadata is prepared and populated. If
any post-processing is required, it will also take place in the same
thread (which can be blocking for a subtaintial amount of time) before
the results can be sent back to the framework.
A follow up commit will move the post-processing to run in a separate
thread. In order to do so, there is few bits of groundwork which this
patch entails. Mainly, we need to preserve the order of sending
the capture results back in which they were queued by the framework
to the HAL (i.e. the order is sequential). Hence, we need to add a queue
in which capture results can be queued with context.
As per this patch, the post-processor still runs synchronously as
before, but it will queue up the current capture results with context.
Later down the line, the capture results are dequeud in order and
sent back to the framework.
The context is preserved using Camera3RequestDescriptor utility
structure. It has been expanded accordingly to address the needs of
the functionality.
Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
src/android/camera_device.cpp | 113 +++++++++++++++++++++++++++++++---
src/android/camera_device.h | 23 +++++++
2 files changed, 126 insertions(+), 10 deletions(-)
diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index 0b324ff5..fd07c9bd 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -240,6 +240,8 @@ CameraDevice::Camera3RequestDescriptor::Camera3RequestDescriptor(
/* Clone the controls associated with the camera3 request. */
settings_ = CameraMetadata(camera3Request->settings);
+ internalBuffer_ = nullptr;
+
/*
* Create the CaptureRequest, stored as a unique_ptr<> to tie its
* lifetime to the descriptor.
@@ -1002,6 +1004,7 @@ int CameraDevice::processCaptureRequest(camera3_capture_request_t *camera3Reques
* once it has been processed.
*/
buffer = cameraStream->getBuffer();
+ descriptor.internalBuffer_ = buffer;
LOG(HAL, Debug) << ss.str() << " (internal)";
break;
}
@@ -1161,25 +1164,115 @@ void CameraDevice::requestComplete(Request *request)
continue;
}
+ /*
+ * Save the current context of capture result and queue the
+ * descriptor before processing the camera stream.
+ *
+ * When the processing completes, the descriptor will be
+ * dequeued and capture results will be sent to the framework.
+ */
+ descriptor.status_ = Camera3RequestDescriptor::NOT_FINISHED;
+ descriptor.resultMetadata_ = std::move(resultMetadata);
+ descriptor.captureResult_ = captureResult;
+
+ std::unique_ptr<Camera3RequestDescriptor> reqDescriptor =
+ std::make_unique<Camera3RequestDescriptor>();
+ *reqDescriptor = std::move(descriptor);
+ queuedDescriptor_.push_back(std::move(reqDescriptor));
+ Camera3RequestDescriptor *currentDescriptor = queuedDescriptor_.back().get();
+
+ CameraMetadata *metadata = currentDescriptor->resultMetadata_.get();
+ cameraStream->processComplete.connect(
+ this, [=](CameraStream::ProcessStatus status) {
+ streamProcessingComplete(cameraStream, status,
+ metadata);
+ });
+
int ret = cameraStream->process(src, *buffer.buffer,
- descriptor.settings_,
- resultMetadata.get());
+ currentDescriptor->settings_,
+ metadata);
+ return;
+ }
+
+ if (queuedDescriptor_.empty()) {
+ captureResult.result = resultMetadata->get();
+ callbacks_->process_capture_result(callbacks_, &captureResult);
+ } else {
+ /*
+ * Previous capture results waiting to be sent to framework
+ * hence, queue the current capture results as well. After that,
+ * check if any results are ready to be sent back to the
+ * framework.
+ */
+ descriptor.status_ = Camera3RequestDescriptor::FINISHED_SUCCESS;
+ descriptor.resultMetadata_ = std::move(resultMetadata);
+ descriptor.captureResult_ = captureResult;
+ std::unique_ptr<Camera3RequestDescriptor> reqDescriptor =
+ std::make_unique<Camera3RequestDescriptor>();
+ *reqDescriptor = std::move(descriptor);
+ queuedDescriptor_.push_back(std::move(reqDescriptor));
+
+ sendQueuedCaptureResults();
+ }
+}
+
+void CameraDevice::streamProcessingComplete(CameraStream *cameraStream,
+ CameraStream::ProcessStatus status,
+ CameraMetadata *resultMetadata)
+{
+ for (auto &d : queuedDescriptor_) {
+ if (d->resultMetadata_.get() != resultMetadata)
+ continue;
+
/*
* Return the FrameBuffer to the CameraStream now that we're
* done processing it.
*/
if (cameraStream->type() == CameraStream::Type::Internal)
- cameraStream->putBuffer(src);
-
- if (ret) {
- buffer.status = CAMERA3_BUFFER_STATUS_ERROR;
- notifyError(descriptor.frameNumber_, buffer.stream,
- CAMERA3_MSG_ERROR_BUFFER);
+ cameraStream->putBuffer(d->internalBuffer_);
+
+ if (status == CameraStream::ProcessStatus::Success) {
+ d->status_ = Camera3RequestDescriptor::FINISHED_SUCCESS;
+ } else {
+ d->status_ = Camera3RequestDescriptor::FINISHED_FAILED;
+ d->captureResult_.partial_result = 0;
+ for (camera3_stream_buffer_t &buffer : d->buffers_) {
+ CameraStream *cs = static_cast<CameraStream *>(buffer.stream->priv);
+
+ if (cs->camera3Stream().format != HAL_PIXEL_FORMAT_BLOB)
+ continue;
+
+ buffer.status = CAMERA3_BUFFER_STATUS_ERROR;
+ notifyError(d->frameNumber_, buffer.stream,
+ CAMERA3_MSG_ERROR_BUFFER);
+ }
}
+
+ break;
}
- captureResult.result = resultMetadata->get();
- callbacks_->process_capture_result(callbacks_, &captureResult);
+ /*
+ * Send back capture results to the framework by inspecting the queue.
+ * The framework can defer queueing further requests to the HAL (via
+ * process_capture_request) unless until it receives the capture results
+ * for already queued requests.
+ */
+ sendQueuedCaptureResults();
+}
+
+void CameraDevice::sendQueuedCaptureResults()
+{
+ while (!queuedDescriptor_.empty()) {
+ std::unique_ptr<Camera3RequestDescriptor> &d = queuedDescriptor_.front();
+ if (d->status_ != Camera3RequestDescriptor::NOT_FINISHED) {
+ d->captureResult_.result = d->resultMetadata_->get();
+ callbacks_->process_capture_result(callbacks_,
+ &(d->captureResult_));
+ queuedDescriptor_.pop_front();
+ } else {
+ break;
+ }
+ }
}
std::string CameraDevice::logPrefix() const
diff --git a/src/android/camera_device.h b/src/android/camera_device.h
index a5576927..36425773 100644
--- a/src/android/camera_device.h
+++ b/src/android/camera_device.h
@@ -7,6 +7,7 @@
#ifndef __ANDROID_CAMERA_DEVICE_H__
#define __ANDROID_CAMERA_DEVICE_H__
+#include <deque>
#include <map>
#include <memory>
#include <mutex>
@@ -83,6 +84,21 @@ private:
std::vector<std::unique_ptr<libcamera::FrameBuffer>> frameBuffers_;
CameraMetadata settings_;
std::unique_ptr<CaptureRequest> request_;
+
+ /*
+ * Below are utility placeholders used when a capture result
+ * needs to be queued before completion via
+ * process_capture_result() callback.
+ */
+ enum completionStatus {
+ NOT_FINISHED,
+ FINISHED_SUCCESS,
+ FINISHED_FAILED,
+ };
+ std::unique_ptr<CameraMetadata> resultMetadata_;
+ camera3_capture_result_t captureResult_;
+ libcamera::FrameBuffer *internalBuffer_;
+ completionStatus status_;
};
enum class State {
@@ -105,6 +121,11 @@ private:
std::unique_ptr<CameraMetadata> getResultMetadata(
const Camera3RequestDescriptor &descriptor) const;
+ void sendQueuedCaptureResults();
+ void streamProcessingComplete(CameraStream *stream,
+ CameraStream::ProcessStatus status,
+ CameraMetadata *resultMetadata);
+
unsigned int id_;
camera3_device_t camera3Device_;
@@ -125,6 +146,8 @@ private:
libcamera::Mutex descriptorsMutex_; /* Protects descriptors_. */
std::map<uint64_t, Camera3RequestDescriptor> descriptors_;
+ std::deque<std::unique_ptr<Camera3RequestDescriptor>> queuedDescriptor_;
+
std::string maker_;
std::string model_;
--
2.31.1
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