Take a YOLO style detection mask, convert it to a pixel mask and visualize it.

draw_det.py

def draw_det(det, size=256):
    g = float(len(det))
    msk = np.zeros((size,size))
    for col in range(det.shape[0]):
        for row in range(det.shape[1]):
            p,x,y,w,h = det[col,row]
            if p > 0.5:
                l = int(size*(col/g+x/g-w/2))
                r = int(size*(col/g+x/g+w/2))
                t = int(size*(row/g+y/g-h/2))
                b = int(size*(row/g+y/g+h/2))
                msk[l:r,t:b] = 1
    plt.imshow(msk)
    plt.show()