英文:
variable inside function not defined despite having it defined globally
问题
I define my dictionary 'frame_dict' outside my for loop. However, when it gets to my forFrame function, despite setting it has a global variable, I get an error saying that frame_dict is not defined. Any help?
import osfrom imageai.Detection import VideoObjectDetectionimport picklePATH_TO_STORE_VIDEOS = "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/Videos"tv_commercial_videos = os.listdir('Videos/')def yolo_neural_network(path_to_videos, tv_commercials):execution_path = os.getcwd()frame_dict = {}for tv_c in tv_commercials:frame_dict.setdefault(tv_c,[])# Use pre trained neural network to label things in videosvid_obj_detect = VideoObjectDetection()# Set and load Yolo modelvid_obj_detect.setModelTypeAsYOLOv3()vid_obj_detect.setModelPath(os.path.join(execution_path,"yolov3.pt"))vid_obj_detect.loadModel()input_file_path = os.path.join(path_to_videos, tv_c)if not os.path.exists("output_from_model_yolov3/"):os.makedirs("output_from_model_yolov3/")output_file_path = os.path.join(execution_path, "output_from_model_yolov3/", "model_yolov3_output_" + tv_c)def forFrame(frame_number, output_array, output_count):global frame_dictframe_dict[tv_c].append(output_count)return frame_dictvid_obj_detect.detectObjectsFromVideo(input_file_path=input_file_path,output_file_path=output_file_path,log_progress=True,frame_detection_interval= 60,minimum_percentage_probability=70,per_frame_function=forFrame,save_detected_video=True)# save dictionaryf = open("yolo_dict.pkl", "wb")# write dict to pickle filepickle.dump(frame_dict, f)# close filef.close()return frame_dictyolo = yolo_neural_network(PATH_TO_STORE_VIDEOS, tv_commercial_videos)
Exception has occurred: ValueErrorAn error occurred. It may be that your input video is invalid. Ensure you specified a proper string value for 'output_file_path' and 'save_detected_video' is not False. Also ensure your per_frame, per_second, per_minute, or video_complete_analysis function is properly configured to receive the right parameters.File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 35, in forFrameframe_dict[tv_c].append(output_count)NameError: name 'frame_dict' is not definedDuring handling of the above exception, another exception occurred:File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 38, in yolo_neural_networkvid_obj_detect.detectObjectsFromVideo(File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 59, in <module>
I tried setting my frame_dict variable as global inside the forFrame function expecting it to recognize it.
英文:
I define my dictionary 'frame_dict' outside my for loop. However, when it gets to my forFrame function, despite setting it has a global variable, I get an error saying that frame_dict is not defined. Any help?
import osfrom imageai.Detection import VideoObjectDetectionimport picklePATH_TO_STORE_VIDEOS = "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/Videos"tv_commercial_videos = os.listdir('Videos/')def yolo_neural_network(path_to_videos, tv_commercials):execution_path = os.getcwd()frame_dict = {}for tv_c in tv_commercials:frame_dict.setdefault(tv_c,[])# Use pre trained neural network to label things in videosvid_obj_detect = VideoObjectDetection()# Set and load Yolo modelvid_obj_detect.setModelTypeAsYOLOv3()vid_obj_detect.setModelPath(os.path.join(execution_path,"yolov3.pt"))vid_obj_detect.loadModel()input_file_path = os.path.join(path_to_videos, tv_c)if not os.path.exists("output_from_model_yolov3/"):os.makedirs("output_from_model_yolov3/")output_file_path = os.path.join(execution_path,"output_from_model_yolov3/", "model_yolov3_output_" + tv_c)def forFrame(frame_number, output_array, output_count):global frame_dictframe_dict[tv_c].append(output_count)return frame_dictvid_obj_detect.detectObjectsFromVideo(input_file_path=input_file_path,output_file_path=output_file_path,log_progress=True,frame_detection_interval= 60,minimum_percentage_probability=70,per_frame_function=forFrame,save_detected_video=True)# save dictionaryf = open("yolo_dict.pkl", "wb")# write dict to pickle filepickle.dump(frame_dict, f)# close filef.close()return frame_dictyolo = yolo_neural_network(PATH_TO_STORE_VIDEOS, tv_commercial_videos)
Exception has occurred: ValueErrorAn error occured. It may be that your input video is invalid. Ensure you specified a proper string value for 'output_file_path' is 'save_detected_video' is not False. Also ensure your per_frame, per_second, per_minute or video_complete_analysis function is properly configured to receive the right parameters.File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 35, in forFrameframe_dict[tv_c].append(output_count)NameError: name 'frame_dict' is not definedDuring handling of the above exception, another exception occurred:File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 38, in yolo_neural_networkvid_obj_detect.detectObjectsFromVideo(File "/Users/jaime.pereira/Library/CloudStorage/OneDrive-OneWorkplace/Benchmark_Project/debug.py", line 59, in <module>
I tried setting my frame_dict variable as global inside the forframe function expecting it to recognise it.
答案1
得分: 1
frame_dict 不是全局变量，它只存在于外部作用域，移除 global 关键字
由于你修改了对象，你不需要再做任何事情：
def forFrame(frame_number, output_array, output_count):frame_dict[tv_c].append(output_count)return frame_dict
由于你没有给 frame_dict 赋任何值，即使这个变量是全局变量，如果你修改了对象，也不需要添加 global 关键字。global 仅在你需要给变量赋新值时有用。
英文:
frame_dict is not a global, it is just in an outer scope, remove global keyword
Since you mutate the object, you don't need to do anything more:
def forFrame(frame_number, output_array, output_count):frame_dict[tv_c].append(output_count)return frame_dict
Since you don't assign anything to frame_dict, even if the variable were a global variable, you wouldn't need to add the global keyword if you mutate the object. global is useful only if you need to assign a new value to the variable.
答案2
得分: 0
你面临的问题是frame_dict实际上不是一个全局变量。它是在yolo_neural_network内部定义的。虽然它确实在forFrame之外，但它不是一个全局变量。
在这种情况下，你应该简单地删除global语句，因为你导入的不是一个全局变量。
英文:
The problem you are facing is that frame_dict is actually not a global variable. It is defined inside of yolo_neural_network. While this is indeed outside forFrame, it is not a global variable.
In this scenario, you should simply remove the global statement, because it is not a global variable you are importing.
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