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Pylon::CPylonImageUserBufferEventHandler#

Module: Image Handling Support

The CPylonImage user buffer event handler base class. More…

#include <pylon/PylonImageUserBufferEventHandler.h>

Public Functions#

Name
virtual void OnPylonImageUserBufferDetached(void * pUserBuffer, size_t bufferSizeBytes)
This method is called after the image class has released its user buffer.

Detailed Description#

class Pylon::CPylonImageUserBufferEventHandler;

The CPylonImage user buffer event handler base class.

You can optionally pass an object derived from this class when calling CPylonImage::AttachUserBuffer(). When the CPylonImage doesn't need the user buffer anymore, it will call the CPylonImageUserBufferEventHandler::OnPylonImageUserBufferDetached() method. You can override this function to execute your custom code when the user buffer has been detached implicitly.

The user is responsible for ensuring the object is valid until CPylonImageUserBufferEventHandler::OnPylonImageUserBufferDetached() has been called.

Public Functions Documentation#

OnPylonImageUserBufferDetached#

inline virtual void OnPylonImageUserBufferDetached(
    void * pUserBuffer,
    size_t bufferSizeBytes
)

This method is called after the image class has released its user buffer.

Parameters:

Error Safety:

This function must not throw any exceptions.

This method is called after the image class releases its image buffer. In case a user buffer has been attached using CPylonImage::AttachUserBuffer() you can use this to free your user buffer.

In case you created the event handler on the heap using new, you can call delete this at the end of the function.

// Sample handler to show how to delete the handler when allocating the handler on the heap.
class MyHandler : public CPylonImageUserBufferEventHandler {
    OnPylonImageUserBufferDetached( void* pUserBuffer, size_t bufferSizeBytes ) override {
        // Use our custom memory allocator to free the user buffer.
        MyCustomFreeMemory( pUserBuffer );

        // Delete the handler.
        delete this;
    }
};

// Use our custom memory allocator for pixel data.
void* pUserBuffer = MyCustomAllocateMemory( 640 * 480 );

// Attach user buffer using a heap-allocated event handler.
CPylonImage image;
image.AttachUserBuffer(pUserBuffer, (640 * 480), PixelType_Mono8, 640, 480, 0, ImageOrientation_TopDown, new MyHandler() );

The default implementation does nothing. You can override this function to execute custom code.


Updated on 5 July 2022 at 15:30:01