The problem of correspondence between the label of the spectrum chart and the mask coordinates

[Jinzhu-Wang]

Describe the bug
When I use MaskClassVisualizer to visualize IQ data, I hope to extract the coordinates of the mask and the corresponding label values. However, when I add the following code, there is a matching problem between labels and coordinates, especially a label with When using multiple masks. Please tell me what should I do

To Reproduce
Code added in MaskClassVisualizerr:

            contours, _ = cv2.findContours((mask * 255).astype(np.uint8), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
            contour_coordinates = []
            for contour in contours:
                contour_coordinates.append(contour.squeeze().tolist())

            print("Contour Coordinates:", contour_coordinates)
            print("idx: ",class_idx)

Output results

            Contour Coordinates: [[[0, 420], [0, 455], [511, 455], [511, 420]], [[0, 129], [0, 204], [187, 204], [187, 129]], [[460, 99], [460, 151], [511, 151], [511, 99]]]
            idx:  [3, 4]

Expected behavior
Like the above output, how should I match them

[ereoh]

Hello, we have two examples that use MaskClassVisualizer, see if those help?

examples/03_example_widebandsig53_dataset.ipynb
examples/04_example_wideband_modulations_dataset.ipynb