有没有办法将我的 YOLO v3 模型连接到我的网络摄像头?

Is there a way to connect my YOLO v3 model to my webcam?

我正在使用 TensorFlow 在 yolo_v3 上关注此 GitHub repo。代码 运行 在单个图像(我从我的计算机加载的图像)上顺利运行,但我正在尝试将模型连接到我的网络摄像头。

我试图研究 OpenCV tutorial on capturing a video from camera,但我无法弄清楚如何将它与启动 TensorFlow 会话的语句结合起来 运行 我的模型:

batch_size = len(img_names)
batch = load_images(img_names, model_size=_MODEL_SIZE)


class_names = load_class_names('files/coco.names')
n_classes = len(class_names)
max_output_size = 10
iou_threshold = 0.5
confidence_threshold = 0.5

tf.reset_default_graph()


model = Yolo_v3(n_classes=n_classes, model_size=_MODEL_SIZE,
            max_output_size=max_output_size,
            iou_threshold=iou_threshold,
            confidence_threshold=confidence_threshold)

inputs = tf.placeholder(tf.float32, [batch_size, 416, 416, 3]) #I think 
that the batch size will be 1 since we're dealing with 1 frame at a time

detections = model(inputs, training=False)
model_vars = tf.global_variables(scope='yolo_v3_model')
assign_ops = load_weights(model_vars, 'files/yolov3.weights')

with tf.Session() as sess:
    sess.run(assign_ops)
    detection_result = sess.run(detections, feed_dict={inputs: batch})

draw_boxes(img_names, detection_result, class_names, _MODEL_SIZE)

编辑:
我试过 运行:

def generator():
    cap = cv2.VideoCapture(0)
    cap.set(3,416)
    cap.set(4,416)

    time.sleep(10)

    while(True):
        # Capture frame-by-frame
        ret, frame = cap.read()

        # Display the resulting frame
        cv2.imshow('frame',frame)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break

        yield frame


with tf.Session() as sess:
    sess.run(assign_ops)
    for frame in generator():
        detection_result = sess.run(detections, feed_dict={inputs: np.expand_dims(frame, 0)})
        draw_boxes(img_names, detection_result, class_names, _MODEL_SIZE)

但是我收到一条错误消息,指出图像未正确加载(空帧),或者:

ValueError: Cannot feed value of shape (1, 240, 320, 3) for Tensor 'Placeholder:0', which has shape '(1, 416, 416, 3)'

编辑 2
我觉得它几乎可以工作了。我运行

def generator():
    cap = cv2.VideoCapture(0)
    while(True):
        # Capture frame-by-frame
        ret, frame = cap.read()
        frame = cv2.resize(frame, (416, 416))
        # Display the resulting frame
        cv2.imshow('frame',frame)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break

        yield frame
    # When everything done, release the capture
    cap.release()
    cv2.destroyAllWindows()


with tf.Session() as sess:
    sess.run(assign_ops)
    for frame in generator():
        detection_result = sess.run(detections, feed_dict={inputs: np.expand_dims(frame, 0)})
        draw_boxes(frame, detection_result, class_names, _MODEL_SIZE)

但是我收到这个错误:

AttributeError: 'numpy.ndarray' object has no attribute 'read'

我尝试 运行 没有最后一部分的代码:

draw_boxes(frame, detection_result, class_names, _MODEL_SIZE)

我的相机确实打开了,尽管没有任何物体检测(YOLO 模型)

顺便说一句,这是draw_boxes函数:

def draw_boxes(img_names, boxes_dicts, class_names, model_size):
    """Draws detected boxes.

    Args:
        img_names: A list of input images names.
        boxes_dict: A class-to-boxes dictionary.
        class_names: A class names list.
        model_size: The input size of the model.

    Returns:
        None.
    """
    for num, img_name, boxes_dict in zip(range(len(img_names)), img_names,
                                         boxes_dicts):
        img = Image.open(img_name)
        draw = ImageDraw.Draw(img)
        font = ImageFont.truetype(font='files/futur.ttf',
                                  size=(img.size[0] + img.size[1]) // 100)
        resize_factor = \
            (img.size[0] / model_size[0], img.size[1] / model_size[1])
        for cls in range(len(class_names)):
            boxes = boxes_dict[cls]
            if np.size(boxes) != 0:
                color = np.random.permutation([np.random.randint(256), 255, 0])
                for box in boxes:
                    xy, confidence = box[:4], box[4] #xy – Top left corner of the text.
                    xy = [xy[i] * resize_factor[i % 2] for i in range(4)]
                    x0, y0 = xy[0], xy[1]
                    thickness = (img.size[0] + img.size[1]) // 200
                    for t in np.linspace(0, 1, thickness):
                        xy[0], xy[1] = xy[0] + t, xy[1] + t
                        xy[2], xy[3] = xy[2] - t, xy[3] - t
                        draw.rectangle(xy, outline=tuple(color))
                    if class_names[cls] =='car':
                        text = '{} {:.1f}% about {:.1f} cm away'.format(class_names[cls], #text – Text to be drawn.
                                                   confidence * 100,
                                                  Distance_To_Obect(4.3,121,780,xy[3]-xy[1],3.5).distance()) 
                    elif class_names[cls] =='person':
                        width, height = img.size
                        print(width, height)
                        text = '{} {:.1f}% about {:.1f} cm away'.format(class_names[cls], #text – Text to be drawn.
                                                   confidence * 100,
                                                  Distance_To_Obect(4.3,170,height,xy[3]-xy[1],3.5).distance()) 

                    else:
                        text = '{} {:.1f}%'.format(class_names[cls], #text – Text to be drawn.
                                                   confidence * 100)
                    text_size = draw.textsize(text, font=font)

                    print ('[x0, y0, x1, y1]', xy[0], xy[1] ,xy[2], xy[3])

                    draw.rectangle(
                        [x0, y0 - text_size[1], x0 + text_size[0], y0],
                        fill=tuple(color)) #fill – Color to use for the text
                    draw.text((x0, y0 - text_size[1]), text, fill='black',
                              font=font)

        display(img)

我尝试更换

img = Image.open(img_name)

Image.fromarray(img_name)

但是我得到了一个错误(在 运行再次打开文件之后):

TypeError: function takes exactly 1 argument (3 given)

此外,我还有 运行

print (detection_result)

它确实包含点数

编辑 3
我尝试将 draw_boxes 方法更改为 this link
中的方法 但是我得到了这个错误:

OSError                                   Traceback (most recent call last)
<ipython-input-5-fa46870a1059> in <module>
    105         detection_result = sess.run(detections, feed_dict={inputs: np.expand_dims(frame, 0)})
    106         print(detection_result)
--> 107         draw_boxes(frame, detection_result, class_names, _MODEL_SIZE)

<ipython-input-5-fa46870a1059> in draw_boxes(image, boxes, box_classes, class_names, scores)
     36     font = ImageFont.truetype(
     37         font='font/FiraMono-Medium.otf',
---> 38         size=np.floor(3e-2 * image.size[1] + 0.5).astype('int32'))
     39     thickness = (image.size[0] + image.size[1]) // 300
     40

~\AppData\Local\Programs\Python\Python36\lib\site-packages\PIL\ImageFont.py in truetype(font, size, index, encoding, layout_engine)
    278
    279     try:
--> 280         return FreeTypeFont(font, size, index, encoding, layout_engine)
    281     except IOError:
    282         ttf_filename = os.path.basename(font)

~\AppData\Local\Programs\Python\Python36\lib\site-packages\PIL\ImageFont.py in __init__(self, font, size, index, encoding, layout_engine)
    143         if isPath(font):
    144             self.font = core.getfont(font, size, index, encoding,
--> 145                                      layout_engine=layout_engine)
    146         else:
    147             self.font_bytes = font.read()

OSError: cannot open resource

编辑 4
顺便说一句,这是 result_box

[{0: array([[131.96371   , 131.70601   , 341.41946   , 358.6781    ,
          0.68467134]], dtype=float32), 1: array([], shape=(0, 5), dtype=float32), 2: array([], shape=(0, 5), dtype=float32), 3: array([], shape=(0, 5), dtype=float32), 4: array([], shape=(0, 5), dtype=float32), 5: array([], shape=(0, 5), dtype=float32), 6: array([], shape=(0, 5), dtype=float32), 7: array([], shape=(0, 5), dtype=float32), 8: array([], shape=(0, 5), dtype=float32), 9: array([], shape=(0, 5), dtype=float32), 10: array([], shape=(0, 5), dtype=float32), 11: array([], shape=(0, 5), dtype=float32), 12: array([], shape=(0, 5), dtype=float32), 13: array([], shape=(0, 5), dtype=float32), 14: array([], shape=(0, 5), dtype=float32), 15: array([], shape=(0, 5), dtype=float32), 16: array([], shape=(0, 5), dtype=float32), 17: array([], shape=(0, 5), dtype=float32), 18: array([], shape=(0, 5), dtype=float32), 19: array([], shape=(0, 5), dtype=float32), 20: array([], shape=(0, 5), dtype=float32), 21: array([], shape=(0, 5), dtype=float32), 22: array([], shape=(0, 5), dtype=float32), 23: array([], shape=(0, 5), dtype=float32), 24: array([], shape=(0, 5), dtype=float32), 25: array([], shape=(0, 5), dtype=float32), 26: array([], shape=(0, 5), dtype=float32), 27: array([], shape=(0, 5), dtype=float32), 28: array([], shape=(0, 5), dtype=float32), 29: array([], shape=(0, 5), dtype=float32), 30: array([], shape=(0, 5), dtype=float32), 31: array([], shape=(0, 5), dtype=float32), 32: array([], shape=(0, 5), dtype=float32), 33: array([], shape=(0, 5), dtype=float32), 34: array([], shape=(0, 5), dtype=float32), 35: array([], shape=(0, 5), dtype=float32), 36: array([], shape=(0, 5), dtype=float32), 37: array([], shape=(0, 5), dtype=float32), 38: array([], shape=(0, 5), dtype=float32), 39: array([], shape=(0, 5), dtype=float32), 40: array([], shape=(0, 5), dtype=float32), 41: array([], shape=(0, 5), dtype=float32), 42: array([], shape=(0, 5), dtype=float32), 43: array([], shape=(0, 5), dtype=float32), 44: array([], shape=(0, 5), dtype=float32), 45: array([], shape=(0, 5), dtype=float32), 46: array([], shape=(0, 5), dtype=float32), 47: array([], shape=(0, 5), dtype=float32), 48: array([], shape=(0, 5), dtype=float32), 49: array([], shape=(0, 5), dtype=float32), 50: array([], shape=(0, 5), dtype=float32), 51: array([], shape=(0, 5), dtype=float32), 52: array([], shape=(0, 5), dtype=float32), 53: array([], shape=(0, 5), dtype=float32), 54: array([], shape=(0, 5), dtype=float32), 55: array([], shape=(0, 5), dtype=float32), 56: array([], shape=(0, 5), dtype=float32), 57: array([], shape=(0, 5), dtype=float32), 58: array([], shape=(0, 5), dtype=float32), 59: array([], shape=(0, 5), dtype=float32), 60: array([], shape=(0, 5), dtype=float32), 61: array([], shape=(0, 5), dtype=float32), 62: array([], shape=(0, 5), dtype=float32), 63: array([], shape=(0, 5), dtype=float32), 64: array([], shape=(0, 5), dtype=float32), 65: array([], shape=(0, 5), dtype=float32), 66: array([], shape=(0, 5), dtype=float32), 67: array([], shape=(0, 5), dtype=float32), 68: array([], shape=(0, 5), dtype=float32), 69: array([], shape=(0, 5), dtype=float32), 70: array([], shape=(0, 5), dtype=float32), 71: array([], shape=(0, 5), dtype=float32), 72: array([], shape=(0, 5), dtype=float32), 73: array([], shape=(0, 5), dtype=float32), 74: array([], shape=(0, 5), dtype=float32), 75: array([], shape=(0, 5), dtype=float32), 76: array([], shape=(0, 5), dtype=float32), 77: array([], shape=(0, 5), dtype=float32), 78: array([], shape=(0, 5), dtype=float32), 79: array([], shape=(0, 5), dtype=float32)}]

在 link 中,您提供的框架是您需要提供给 yolo 的图像。您可以将 link 中的整个 while true 放入会话中,然后按 运行:

逐帧处理
detection_result = sess.run(detections, feed_dict={inputs: np.expand_dims(frame, 0)})

或者写一个提供框架的生成器,更干净一些。

def generator()
    cap = cv2.VideoCapture(0)
    while(True):
        # Capture frame-by-frame
        ret, frame = cap.read()
        frame = cv2.resize(frame, (416, 416))
        yield frame

然后你可以做:

with tf.Session() as sess:
    sess.run(assign_ops)
    for frame in generator():
        detection_result = sess.run(detections, feed_dict={inputs: np.expand_dims(frame, 0)})

expand dims 是创建一批 1,所以例如:将 399x399x3 变成 1x399x399x3。

大概就是这样,希望对你有所帮助

编辑

import numpy as np
import cv2


def convert_bbox_to_absolute(bbox_list, w_img, h_img):
    """
    method to convert the relative points (< 1) to absolute points (< 416)
    :param bbox_list: (list) list of boundary boxes (x, y, w, h, probability)
    :param w_img: (int) width of the image
    :param h_img: (int) height of the image
    :return: bbox_list: (list) list of boundary boxes but this time scaled up
    """
    x, y, w, h, c = zip(*bbox_list)
    y = list(map(lambda y: int(y * w_img), y))
    w = list(map(lambda w: int(w * h_img), w))

    x = list(map(lambda x: int(x * h_img), x))
    h = list(map(lambda h: int(h * w_img), h))
    bbox_list = zip(x, y, w, h, c)
    return list(bbox_list)


def draw_boxes(image, bbox_list):
    """
    Will draw the rectangles on th image and place the probability on them
    :param image:  (np.ndarray) a RGB-color image
    :param bbox_list: (list) list of boundary boxes (x, y, w, h, probability)
    """
    assert type(image) == np.ndarray
    assert type(bbox_list) == list

    assert len(image.shape) == 3
    assert len(bbox_list[0]) == 5

    # get the width and height of the image
    w_img, h_img, _ = image.shape

    # convert the box coordinates to absolute values
    bbox_list = convert_bbox_to_absolute(bbox_list, w_img, h_img)
    for bbox in bbox_list:
        x, y, w, h, c = bbox
        cv2.rectangle(image, (x, y), (x+w, y+h), (0, 255, 0), 3)
        cv2.putText(image, str(c), (x, y), cv2.FONT_HERSHEY_SIMPLEX, 1, (255, 255, 255), 2)
    cv2.imshow("", image)
    cv2.waitKey(0)


# creating a black test RGB-image
test_image = np.zeros((512, 416, 3))

# faking some boundary boxes, x, y, w, h, confidence
b_boxes = [[0.5, 0.1, 0.5, 0.9, 0.8], [0.4, 0.1, 0.1, 0.1, 0.4]]

draw_boxes(test_image, b_boxes)

这是一个非常简单的示例,说明如何绘制边界框,我假设 yolo 提供的边界框已归一化,因为 this link。如果您知道我如何确定哪个标签属于哪个框,那么我也会将其添加到代码中。

编辑 2:

import numpy as np
import cv2
from random import choices
from string import ascii_lowercase


def draw_boxes(image, bbox_list, label_list):
    """
    Will draw the rectangles on th image and place the probability on them
    :param image:  (np.ndarray) a RGB-color image
    :param bbox_list: (list[dict()]) list dict of boundary boxes  label:(x, y, w, h, probability)
    :param label_list: (list) a list of label names matching the order of the dict keys
    """
    bbox_dict = bbox_list[0]
    assert type(image) == np.ndarray
    assert type(bbox_dict) == dict
    assert type(label_list) == list

    assert len(image.shape) == 3
    assert len(bbox_dict.keys()) == 80
    assert len(label_list) == 80

    for label, bbox in bbox_dict.items():
        if bbox.size == 0:
            continue
        x1, y1, x2, y2, c = np.squeeze(bbox)
        x1, y1, x2, y2 = list(map(lambda val: int(val), [x1, y1, x2, y2]))
        label = label_list[label] + ": {}".format(c)

        cv2.rectangle(image, (x1, y1), (x2, y2), (0, 255, 0), 3)
        cv2.putText(image, label, (x1, y1), cv2.FONT_HERSHEY_SIMPLEX, 1, (255, 255, 255), 2)
    cv2.imshow("", image)
    cv2.waitKey(0)


# creating a black test RGB-image
test_image = np.zeros((512, 416, 3))

# faking some boundary boxes, x, y, w, h, confidence and auto generating empty arrays with keys, to match your data
b_boxes = [{
    0: np.array([[131.96371, 131.70601, 341.41946, 358.6781, 0.68467134]]),
    1: np.array([])
}]
for i in range(2, 80):
    b_boxes[0][i] = np.array([])

# get 80 random 10 letter strings to mock labels
labels = ["".join(choices(ascii_lowercase, k=10)) for _ in range(80)]

draw_boxes(test_image, b_boxes, labels)

根据您的数据,我做了一些修改,希望对您有所帮助