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HDRReader

vtk-examples/Python/IO/HDRReader


Description

Demonstrates how to read high-dynamic-range imaging files.

A callback is used to print out the color window (move the mouse horizontally over the image) and color level (move the mouse vertically over the image).

This is based on IO/Image/Testing/Cxx/TestHDRReader.cxx in the VTK source files.

Other languages

See (Cxx)

Question

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Code

HDRReader.py

##!/usr/bin/env python

import vtk


def get_program_parameters():
    import argparse
    description = 'Demonstrate the use of HDRReader'
    epilogue = '''
This example shows how to read in an HDR file.
A callback is used to print out the color window (move the mouse horizontally over the image)
 and color level (move the mouse vertically over the image).

   '''
    parser = argparse.ArgumentParser(description=description, epilog=epilogue,
                                     formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument('file_name', help='Path to the hdr file e.g. skyboxes/spiaggia_di_mondello_1k.hdr.')
    args = parser.parse_args()
    return args.file_name


def main():
    file_name = get_program_parameters()

    reader = vtk.vtkHDRReader()

    # Check the image can be read
    if not reader.CanReadFile(file_name):
        print('CanReadFile failed for ', file_name)
        return

    reader.SetFileName(file_name)
    reader.UpdateInformation()

    # Whole extent
    we = reader.GetDataExtent()
    extents = [we[0], we[1], we[2], we[3], 0, 0]
    reader.UpdateExtent(extents)
    # Visualize
    image_viewer = vtk.vtkImageViewer()
    image_viewer.SetInputData(reader.GetOutput())

    image_viewer.SetColorWindow(1)
    image_viewer.SetColorLevel(1)
    image_viewer.SetPosition(0, 100)

    iren = vtk.vtkRenderWindowInteractor()
    image_viewer.SetupInteractor(iren)
    image_viewer.GetRenderWindow().SetWindowName('HDRReader')
    image_viewer.Render()

    iren.AddObserver('EndInteractionEvent', ColorCallback(image_viewer))

    iren.Start()


class ColorCallback(object):
    def __init__(self, image_viewer):
        self.image_viewer = image_viewer

    def __call__(self, caller, ev):
        # Just do this to demonstrate who called callback and the event that triggered it.
        # print(caller.GetClassName(), 'Event Id:', ev)

        res = 'Color window: {} level: {}'.format(self.image_viewer.GetColorWindow(),
                                                  self.image_viewer.GetColorLevel())
        print(res)


if __name__ == '__main__':
    main()