A class referencing the native frame data. The data is held externally to the MicroPython heap.
It has no methods, but implements the buffer protocol and can be passed to functions expecting a buffer (it implements the buffer protocol), such as neural_network.run() or npufs.write().
It can be copied into MicroPython’s heap for further processing e.g. by using it as the constructor parameter for a bytes() or bytearray() object.
Note:
The ExternalBuffer can only be used while its originating frame object is valid. When the frame is released, it will act as an empty buffer.