Comment # 3 on bug 109679 from Stuart Summers

Agree this looks like an issue in IGT or possibly in the chameleond daemon. At
a quick glance, there aren't a whole lot of places in the CaptureVideo path
that might trigger this exception in chameleond. It does look feasible that if
we were to pass a 0 for width and height, we could potentially get a
div-by-zero exception when chameleond prepares the video output:
CaptureVideo ->
_PrepareCapturingVideo/_captured_params['max_frame_limit']/flow_manager.GetMaxFrameLimit
-> input_flow.GetMaxFrameLimit -> frame_manager.GetMaxFrameLimit ->
field_manager.GetMaxFieldLimit -> VideoDumper.GetMaxFieldLimit:
  def GetMaxFieldLimit(cls, width, height):                          
    """Returns of the maximal number of fields which can be dumped.""" 
    BYTE_PER_PIXEL = 3                                                 
    PAGE_SIZE = 4096                                                         
    field_size = width * height * BYTE_PER_PIXEL   
    field_size = ((field_size - 1) / PAGE_SIZE + 1) * PAGE_SIZE
    return cls._DUMP_BUFFER_SIZE / field_size

That said, running this myself locally does not result in the failure of this
sighting, and from kms_chamelium.c, during the CRC check, we are passing 0 for
width and height:
  chamelium_capture(data->chamelium, port, 0, 0, 0, 0, count);

So I'd expect this to fail all the time if the issue were in the Python call I
indicated above.

And I'd also expect for CI to have seen this already if that were the case,
given this code has been present for some time.