[libcamera-devel,09/27] libcamera: v4l2_device: Update dequeued buffer information

524 diff mbox series

diff --git a/include/libcamera/buffer.h b/include/libcamera/buffer.h
index 21a1ec4c574e..dc9aaad12a81 100644
--- a/include/libcamera/buffer.h
+++ b/include/libcamera/buffer.h
@@ -7,6 +7,7 @@ 
 #ifndef __LIBCAMERA_BUFFER_H__
 #define __LIBCAMERA_BUFFER_H__
 
+#include <stdint.h>
 #include <vector>
 
 #include <libcamera/signal.h>
@@ -42,14 +43,21 @@  public:
 	Buffer();
 
 	unsigned int index() const { return index_; }
+	unsigned int bytesused() const { return bytesused_; }
+	uint64_t timestamp() const { return timestamp_; }
+	unsigned int sequence() const { return sequence_; }
 	std::vector<Plane> &planes() { return planes_; }
 
 	Signal<Buffer *> completed;
 
 private:
 	friend class BufferPool;
+	friend class V4L2Device;
 
 	unsigned int index_;
+	unsigned int bytesused_;
+	uint64_t timestamp_;
+	unsigned int sequence_;
 
 	std::vector<Plane> planes_;
 };
diff --git a/src/libcamera/buffer.cpp b/src/libcamera/buffer.cpp
index 5f6114cf3bc5..9ec372c2981b 100644
--- a/src/libcamera/buffer.cpp
+++ b/src/libcamera/buffer.cpp
@@ -203,6 +203,32 @@  Buffer::Buffer()
  * \brief A Signal to provide notifications that the specific Buffer is ready
  */
 
+/**
+ * \fn Buffer::bytesused()
+ * \brief Retrieve the number of bytes occupied by the data in the buffer
+ * \return Number of bytes occupied in the buffer
+ */
+
+/**
+ * \fn Buffer::timestamp()
+ * \brief Retrieve the time when the buffer was processed
+ *
+ * The timestamp is expressed as a number number of nanoseconds since the epoch.
+ *
+ * \return Timestamp when the buffer was processed
+ */
+
+/**
+ * \fn Buffer::sequence()
+ * \brief Retrieve the buffer sequence number
+ *
+ * The sequence number is a monotonically increasing number assigned to the
+ * buffer processed by the stream. Gaps in the sequence numbers indicate
+ * dropped frames.
+ *
+ * \return Sequence number of the buffer
+ */
+
 /**
  * \class BufferPool
  * \brief A pool of buffers
diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp
index f9839fc715f4..e8755be1f63f 100644
--- a/src/libcamera/v4l2_device.cpp
+++ b/src/libcamera/v4l2_device.cpp
@@ -9,6 +9,7 @@ 
 #include <string.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
+#include <sys/time.h>
 #include <unistd.h>
 #include <vector>
 
@@ -723,7 +724,14 @@  Buffer *V4L2Device::dequeueBuffer()
 	if (--queuedBuffersCount_ == 0)
 		fdEvent_->setEnabled(false);
 
-	return &bufferPool_->buffers()[buf.index];
+	Buffer *buffer = &bufferPool_->buffers()[buf.index];
+
+	buffer->bytesused_ = buf.bytesused;
+	buffer->timestamp_ = buf.timestamp.tv_sec * 1000000000ULL
+			   + buf.timestamp.tv_usec * 1000ULL;
+	buffer->sequence_ = buf.sequence;
+
+	return buffer;
 }
 
 /**