Preprocessors

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Preprocessors take an initial image from a webcam or file, and transform it into a processable image, typically by resizing the image or converting the color space of the image to a proper format.

These preprocessors are derived from the BasePreprocessor class, which defines the methods that all preprocessors need to have.

Documented below are the main methods of preprocessor classes.

resize(image, width, height)

Resize an image.

Parameters:

• image (np.ndarray) – The image object to resize.
• width (int) – The width of the resulting image.
• height (int) – The height of the resulting image.

Returns:

The resized image object.

Return type:

np.ndarray

recolor(image, colorspace)

Change the color space of an image using OpenCV’s color conversion methods.

Parameters:

• image (np.ndarray) – Image to change color space of.
• colorspace (int) – Color space to change image to. Comes from cv2.COLOR_* enum.

Returns:

The recolored image object.

Return type:

np.ndarray