deep_learning_object_detection.py

# import the necessary packages
import numpy as np
import cv2

# initialize the list of class labels MobileNet SSD was trained to
# detect, then generate a set of bounding box colors for each class
CLASSES = ["background", "aeroplane", "bicycle", "bird", "boat",
           "bottle", "bus", "car", "cat", "chair", "cow", "diningtable",
           "dog", "horse", "motorbike", "person", "pottedplant", "sheep",
           "sofa", "train", "tvmonitor"]
COLORS = np.random.uniform(0, 255, size=(len(CLASSES), 3))
# load our serialized model from disk
print("[INFO] loading model...")
net = cv2.dnn.readNetFromCaffe("dl_models/MobileNetSSD_deploy.prototxt.txt", "dl_models/MobileNetSSD_deploy.caffemodel")


def detect(image):
    # load the input image and construct an input blob for the image
    # by resizing to a fixed 300x300 pixels and then normalizing it
    # (note: normalization is done via the authors of the MobileNet SSD
    # implementation)
    image = cv2.imread(image)
    (h, w) = image.shape[:2]
    blob = cv2.dnn.blobFromImage(cv2.resize(image, (300, 300)), 0.007843, (300, 300), 127.5)
    # pass the blob through the network and obtain the detections and
    # predictions
    print("[INFO] computing object detections...")
    net.setInput(blob)
    detections = net.forward()
    label = None
    # loop over the detections
    for i in np.arange(0, detections.shape[2]):
        # extract the confidence (i.e., probability) associated with the
        # prediction
        confidence = detections[0, 0, i, 2]
        # filter out weak detections by ensuring the `confidence` is
        # greater than the minimum confidence
        if confidence > 0.4:
            idx = int(detections[0, 0, i, 1])
            # display the prediction
            if CLASSES[idx] == "dog":
                label = "{}: {:.2f}%".format(CLASSES[idx], confidence * 100)
                print("[INFO] {}".format(label))
    return label