[libcamera-devel] [RFC 2/8] libcamera: stream: Provide accessors to buffers
Jacopo Mondi
jacopo at jmondi.org
Sun Jun 30 20:10:43 CEST 2019
All interactions with the Stream's buffers currently go through the
BufferPool. In order to shorten accessing the buffers array, and
restrict access to the Stream's internal buffer pool, provide operations
to access the buffers, create and destriy them.
It is still possible to access the pool for pipeline handlers to
populate it by exporting buffers from a video device to the pool.
Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
include/libcamera/stream.h | 12 ++++++++++
src/cam/capture.cpp | 4 ++--
src/libcamera/camera.cpp | 6 ++---
src/libcamera/pipeline/ipu3/ipu3.cpp | 4 ++--
src/libcamera/stream.cpp | 35 +++++++++++++++++++++++-----
src/qcam/main_window.cpp | 4 +---
test/camera/capture.cpp | 3 +--
test/camera/statemachine.cpp | 3 +--
8 files changed, 51 insertions(+), 20 deletions(-)
diff --git a/include/libcamera/stream.h b/include/libcamera/stream.h
index 5b4fea324ce4..fa7d6ba4987c 100644
--- a/include/libcamera/stream.h
+++ b/include/libcamera/stream.h
@@ -66,12 +66,24 @@ class Stream
{
public:
Stream();
+ /*
+ * FIXME:
+ * If I could find a way to export buffers in pipeline handlers
+ * without accessing the pool with
+ * video_->exportBuffers(&stream->bufferPool());
+ * we could remove access to the internal pool completely.
+ */
BufferPool &bufferPool() { return bufferPool_; }
+ std::vector<Buffer> &buffers() { return bufferPool_.buffers(); }
+ unsigned int bufferCount() const { return bufferPool_.count(); }
const StreamConfiguration &configuration() const { return configuration_; }
protected:
friend class Camera;
+ void createBuffers(unsigned int count);
+ void destroyBuffers();
+
BufferPool bufferPool_;
StreamConfiguration configuration_;
};
diff --git a/src/cam/capture.cpp b/src/cam/capture.cpp
index 6b842d73390d..1bcc9c7e9cf4 100644
--- a/src/cam/capture.cpp
+++ b/src/cam/capture.cpp
@@ -76,7 +76,7 @@ int Capture::capture(EventLoop *loop)
unsigned int nbuffers = UINT_MAX;
for (StreamConfiguration &cfg : *config_) {
Stream *stream = cfg.stream();
- nbuffers = std::min(nbuffers, stream->bufferPool().count());
+ nbuffers = std::min(nbuffers, stream->bufferCount());
}
/*
@@ -95,7 +95,7 @@ int Capture::capture(EventLoop *loop)
std::map<Stream *, Buffer *> map;
for (StreamConfiguration &cfg : *config_) {
Stream *stream = cfg.stream();
- map[stream] = &stream->bufferPool().buffers()[i];
+ map[stream] = &stream->buffers()[i];
}
ret = request->setBuffers(map);
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index 617ea99cdf71..023ae53e5f9d 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -671,7 +671,7 @@ int Camera::configure(CameraConfiguration *config)
* Allocate buffer objects in the pool.
* Memory will be allocated and assigned later.
*/
- stream->bufferPool().createBuffers(cfg.bufferCount);
+ stream->createBuffers(cfg.bufferCount);
}
state_ = CameraConfigured;
@@ -728,14 +728,14 @@ int Camera::freeBuffers()
return -EACCES;
for (Stream *stream : activeStreams_) {
- if (!stream->bufferPool().count())
+ if (!stream->bufferCount())
continue;
/*
* All mappings must be destroyed before buffers can be freed
* by the V4L2 device that has allocated them.
*/
- stream->bufferPool().destroyBuffers();
+ stream->destroyBuffers();
}
state_ = CameraConfigured;
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index e4efb9722f76..2de0892138a8 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -634,7 +634,7 @@ int PipelineHandlerIPU3::allocateBuffers(Camera *camera,
* of buffers as the active ones.
*/
if (!outStream->active_) {
- bufferCount = vfStream->bufferPool().count();
+ bufferCount = vfStream->bufferCount();
outStream->device_->pool->createBuffers(bufferCount);
ret = imgu->exportBuffers(outStream->device_,
outStream->device_->pool);
@@ -643,7 +643,7 @@ int PipelineHandlerIPU3::allocateBuffers(Camera *camera,
}
if (!vfStream->active_) {
- bufferCount = outStream->bufferPool().count();
+ bufferCount = outStream->bufferCount();
vfStream->device_->pool->createBuffers(bufferCount);
ret = imgu->exportBuffers(vfStream->device_,
vfStream->device_->pool);
diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
index d8e87c62281c..c6701e5f9921 100644
--- a/src/libcamera/stream.cpp
+++ b/src/libcamera/stream.cpp
@@ -408,14 +408,12 @@ Stream::Stream()
}
/**
- * \fn Stream::bufferPool()
- * \brief Retrieve the buffer pool for the stream
+ * \fn Stream::buffers()
+ * \brief Retrieve the stream's buffers
*
- * The buffer pool handles the buffers used to capture frames at the output of
- * the stream. It is initially created empty and shall be populated with
- * buffers before being used.
+ * \todo
*
- * \return A reference to the buffer pool
+ * \return The list of stream's buffers
*/
/**
@@ -424,6 +422,31 @@ Stream::Stream()
* \return The active configuration of the stream
*/
+/**
+ * \brief Create buffers for the stream
+ *
+ * \todo
+ */
+void Stream::createBuffers(unsigned int count)
+{
+ bufferPool_.destroyBuffers();
+
+ if (count == 0)
+ return;
+
+ bufferPool_.createBuffers(count);
+}
+
+/**
+ * \brief Destroy buffers in the stream
+ *
+ * \todo
+ */
+void Stream::destroyBuffers()
+{
+ createBuffers(0);
+}
+
/**
* \var Stream::bufferPool_
* \brief The pool of buffers associated with the stream
diff --git a/src/qcam/main_window.cpp b/src/qcam/main_window.cpp
index 16b123132dd9..a0703b322c16 100644
--- a/src/qcam/main_window.cpp
+++ b/src/qcam/main_window.cpp
@@ -122,10 +122,8 @@ int MainWindow::startCapture()
return ret;
}
- BufferPool &pool = stream->bufferPool();
std::vector<Request *> requests;
-
- for (Buffer &buffer : pool.buffers()) {
+ for (Buffer &buffer : stream->buffers()) {
Request *request = camera_->createRequest();
if (!request) {
std::cerr << "Can't create request" << std::endl;
diff --git a/test/camera/capture.cpp b/test/camera/capture.cpp
index 7ce247cc482d..a0385ec2c74d 100644
--- a/test/camera/capture.cpp
+++ b/test/camera/capture.cpp
@@ -76,9 +76,8 @@ protected:
}
Stream *stream = cfg.stream();
- BufferPool &pool = stream->bufferPool();
std::vector<Request *> requests;
- for (Buffer &buffer : pool.buffers()) {
+ for (Buffer &buffer : stream->buffers()) {
Request *request = camera_->createRequest();
if (!request) {
cout << "Failed to create request" << endl;
diff --git a/test/camera/statemachine.cpp b/test/camera/statemachine.cpp
index 84d2a6fab5f0..c23455b5bb21 100644
--- a/test/camera/statemachine.cpp
+++ b/test/camera/statemachine.cpp
@@ -211,8 +211,7 @@ protected:
return TestFail;
Stream *stream = *camera_->streams().begin();
- BufferPool &pool = stream->bufferPool();
- Buffer &buffer = pool.buffers().front();
+ Buffer &buffer = stream->buffers().front();
std::map<Stream *, Buffer *> map = { { stream, &buffer } };
if (request->setBuffers(map))
return TestFail;
--
2.21.0
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