lavis/common/gradcam.py

import numpy as np
from matplotlib import pyplot as plt
from scipy.ndimage import filters
from skimage import transform as skimage_transform


def getAttMap(img, attMap, blur=True, overlap=True):
    attMap -= attMap.min()
    if attMap.max() > 0:
        attMap /= attMap.max()
    attMap = skimage_transform.resize(attMap, (img.shape[:2]), order=3, mode="constant")
    if blur:
        attMap = filters.gaussian_filter(attMap, 0.02 * max(img.shape[:2]))
        attMap -= attMap.min()
        attMap /= attMap.max()
    cmap = plt.get_cmap("jet")
    attMapV = cmap(attMap)
    attMapV = np.delete(attMapV, 3, 2)
    if overlap:
        attMap = (
            1 * (1 - attMap**0.7).reshape(attMap.shape + (1,)) * img
            + (attMap**0.7).reshape(attMap.shape + (1,)) * attMapV
        )
    return attMap