TypeError: object of type 'METADATA' has no len()

[Kian-Strasser]

Hey I tried to use yolov4 on my webcam with this code:

from ctypes import * # Import libraries import math import random import os import cv2 import numpy as np import time import darknet

def convertBack(x, y, w, h): xmin = int(round(x - (w / 2))) xmax = int(round(x + (w / 2))) ymin = int(round(y - (h / 2))) ymax = int(round(y + (h / 2))) return xmin, ymin, xmax, ymax

def cvDrawBoxes(detections, img):

Colored labels dictionary

color_dict = {
    'person' : [0, 255, 255], 'bicycle': [238, 123, 158], 'car' : [24, 245, 217], 'motorbike' : [224, 119, 227],
    'aeroplane' : [154, 52, 104], 'bus' : [179, 50, 247], 'train' : [180, 164, 5], 'truck' : [82, 42, 106],
    'boat' : [201, 25, 52], 'traffic light' : [62, 17, 209], 'fire hydrant' : [60, 68, 169], 'stop sign' : [199, 113, 167],
    'parking meter' : [19, 71, 68], 'bench' : [161, 83, 182], 'bird' : [75, 6, 145], 'cat' : [100, 64, 151],
    'dog' : [156, 116, 171], 'horse' : [88, 9, 123], 'sheep' : [181, 86, 222], 'cow' : [116, 238, 87],'elephant' : [74, 90, 143],
    'bear' : [249, 157, 47], 'zebra' : [26, 101, 131], 'giraffe' : [195, 130, 181], 'backpack' : [242, 52, 233],
    'umbrella' : [131, 11, 189], 'handbag' : [221, 229, 176], 'tie' : [193, 56, 44], 'suitcase' : [139, 53, 137],
    'frisbee' : [102, 208, 40], 'skis' : [61, 50, 7], 'snowboard' : [65, 82, 186], 'sports ball' : [65, 82, 186],
    'kite' : [153, 254, 81],'baseball bat' : [233, 80, 195],'baseball glove' : [165, 179, 213],'skateboard' : [57, 65, 211],
    'surfboard' : [98, 255, 164],'tennis racket' : [205, 219, 146],'bottle' : [140, 138, 172],'wine glass' : [23, 53, 119],
    'cup' : [102, 215, 88],'fork' : [198, 204, 245],'knife' : [183, 132, 233],'spoon' : [14, 87, 125],
    'bowl' : [221, 43, 104],'banana' : [181, 215, 6],'apple' : [16, 139, 183],'sandwich' : [150, 136, 166],'orange' : [219, 144, 1],
    'broccoli' : [123, 226, 195],'carrot' : [230, 45, 209],'hot dog' : [252, 215, 56],'pizza' : [234, 170, 131],
    'donut' : [36, 208, 234],'cake' : [19, 24, 2],'chair' : [115, 184, 234],'sofa' : [125, 238, 12],
    'pottedplant' : [57, 226, 76],'bed' : [77, 31, 134],'diningtable' : [208, 202, 204],'toilet' : [208, 202, 204],
    'tvmonitor' : [208, 202, 204],'laptop' : [159, 149, 163],'mouse' : [148, 148, 87],'remote' : [171, 107, 183],
    'keyboard' : [33, 154, 135],'cell phone' : [206, 209, 108],'microwave' : [206, 209, 108],'oven' : [97, 246, 15],
    'toaster' : [147, 140, 184],'sink' : [157, 58, 24],'refrigerator' : [117, 145, 137],'book' : [155, 129, 244],
    'clock' : [53, 61, 6],'vase' : [145, 75, 152],'scissors' : [8, 140, 38],'teddy bear' : [37, 61, 220],
    'hair drier' : [129, 12, 229],'toothbrush' : [11, 126, 158]
}

for detection in detections:
    x, y, w, h = detection[2][0],\
        detection[2][1],\
        detection[2][2],\
        detection[2][3]
    name_tag = str(detection[0].decode())
    for name_key, color_val in color_dict.items():
        if name_key == name_tag:
            color = color_val 
            xmin, ymin, xmax, ymax = convertBack(
            float(x), float(y), float(w), float(h))
            pt1 = (xmin, ymin)
            pt2 = (xmax, ymax)
            cv2.rectangle(img, pt1, pt2, color, 1)
            cv2.putText(img,
                        detection[0].decode() +
                        " [" + str(round(detection[1] * 100, 2)) + "]",
                        (pt1[0], pt1[1] - 5), cv2.FONT_HERSHEY_SIMPLEX, 0.5,
                        color, 2)
return img

netMain = None metaMain = None altNames = None

def YOLO():

global metaMain, netMain, altNames
configPath = "./cfg/yolov4.cfg"                                 # Path to cfg
weightPath = "./yolov4.weights"                                 # Path to weights
metaPath = "./cfg/coco.data"                                    # Path to meta data
if not os.path.exists(configPath):                              # Checks whether file exists otherwise return ValueError
    raise ValueError("Invalid config path `" +
                     os.path.abspath(configPath)+"`")
if not os.path.exists(weightPath):
    raise ValueError("Invalid weight path `" +
                     os.path.abspath(weightPath)+"`")
if not os.path.exists(metaPath):
    raise ValueError("Invalid data file path `" +
                     os.path.abspath(metaPath)+"`")
if netMain is None:                                             # Checks the metaMain, NetMain and altNames. Loads it in script
    netMain = darknet.load_net_custom(configPath.encode( 
        "ascii"), weightPath.encode("ascii"), 0, 1)             # batch size = 1
if metaMain is None:
    metaMain = darknet.load_meta(metaPath.encode("ascii"))
if altNames is None:
    try:
        with open(metaPath) as metaFH:
            metaContents = metaFH.read()
            import re
            match = re.search("names *= *(.*)$", metaContents,
                              re.IGNORECASE | re.MULTILINE)
            if match:
                result = match.group(1)
            else:
                result = None
            try:
                if os.path.exists(result):
                    with open(result) as namesFH:
                        namesList = namesFH.read().strip().split("\n")
                        altNames = [x.strip() for x in namesList]
            except TypeError:
                pass
    except Exception:
        pass
cap = cv2.VideoCapture(0)                                      # Uncomment to use Webcam
#cap = cv2.VideoCapture("videosos.mp4")                             # Local Stored video detection - Set input video
frame_width = int(cap.get(3))                                   # Returns the width and height of capture video
frame_height = int(cap.get(4))
# Set out for video writer
out = cv2.VideoWriter(                                          # Set the Output path for video writer
    "./Demo/output.avi", cv2.VideoWriter_fourcc(*"MJPG"), 10.0,
    (frame_width, frame_height))

print("Starting the YOLO loop...")

# Create an image we reuse for each detect
darknet_image = darknet.make_image(frame_width, frame_height, 3) # Create image according darknet for compatibility of network
while True:                                                      # Load the input frame and write output frame.
    prev_time = time.time()
    ret, frame_read = cap.read()                                 # Capture frame and return true if frame present
    # For Assertion Failed Error in OpenCV
    if not ret:                                                  # Check if frame present otherwise he break the while loop
        break

    frame_rgb = cv2.cvtColor(frame_read, cv2.COLOR_BGR2RGB)      # Convert frame into RGB from BGR and resize accordingly
    frame_resized = cv2.resize(frame_rgb,
                               (frame_width, frame_height),
                               interpolation=cv2.INTER_LINEAR)

    darknet.copy_image_from_bytes(darknet_image,frame_resized.tobytes())                # Copy that frame bytes to darknet_image

    detections = darknet.detect_image(netMain, metaMain, darknet_image, thresh=0.25)    # Detection occurs at this line and return detections, for customize we can change the threshold.                                                                                   
    image = cvDrawBoxes(detections, frame_resized)               # Call the function cvDrawBoxes() for colored bounding box per class
    image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)
    print(1/(time.time()-prev_time))
    cv2.imshow('Demo', image)                                    # Display Image window
    cv2.waitKey(3)
    out.write(image)                                             # Write that frame into output video
cap.release()                                                    # For releasing cap and out. 
out.release()
print(":::Video Write Completed")

if name == "main":
YOLO() # Calls the main function YOLO()

But I get the error: Traceback (most recent call last): File "darknet_video_mod.py", line 150, in YOLO() # Calls the main function YOLO() File "darknet_video_mod.py", line 138, in YOLO detections = darknet.detect_image(netMain, metaMain, darknet_image, thresh=0.25) # Detection occurs at this line and return detections, for customize we can change the threshold. File "C:\yolo_v4\darknet\build\darknet\x64\darknet.py", line 173, in detect_image do_nms_sort(detections, num, len(class_names), nms) TypeError: object of type 'METADATA' has no len() [ WARN:0] terminating async callback

Can you please help me.

[wusonglin12138]

I have got the same problem, could you solve it ? Traceback (most recent call last): File "/opt/ros/melodic/lib/python2.7/dist-packages/rospy/topics.py", line 750, in _invoke_callback cb(msg) File "droneui.py", line 393, in cameraCallback self.show_detector() File "droneui.py", line 558, in show_detector detections = darknet.detect_image(netMain, metaMain, darknet_image, thresh=0.25) File "/home/drone1/darknet/darknet.py", line 174, in detect_image do_nms_sort(detections, num, len(class_names), nms) TypeError: object of type 'METADATA' has no len()

[yamiefun]

Same problem here, is there any solution so far?

[SunSonia]

Same problem. Have anyone solved it?