Error while extracting the frames for some videos

[aminebdj]

Dear authors,

Thanks a lot for your work,

I am facing some issues while extracting some videos that are downloaded. I am getting the following error.

File "<path>/DriveAGI/opendv/utils/frame_extraction.py", line 41, in extract_frames
    cv2_extract_frames(video_path, output_dir, fps, discard_begin, discard_end, exception_file)
  File "<path>/DriveAGI/opendv/utils/frame_extraction.py", line 145, in cv2_extract_frames
    num_frames = int( fps * (video.get(7) // video_fps - discard_begin - discard_end) )
ZeroDivisionError: float floor division by zero
Traceback (most recent call last):
  File "<path>/DriveAGI/opendv/utils/frame_extraction.py", line 41, in extract_frames
    cv2_extract_frames(video_path, output_dir, fps, discard_begin, discard_end, exception_file)
  File "<path>/DriveAGI/opendv/utils/frame_extraction.py", line 145, in cv2_extract_frames
    num_frames = int( fps * (video.get(7) // video_fps - discard_begin - discard_end) )
ZeroDivisionError: float floor division by zero

There are the videos saved in the exception file

{
    "video_path": "OpenDV-YouTube/videos/Road_Therapy/-G92wLAhsWk.mp4",
    "problem": "float floor division by zero",
    "action": "skipped",
    "details": "Traceback (most recent call last):\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 41, in extract_frames\n    cv2_extract_frames(video_path, output_dir, fps, discard_begin, discard_end, exception_file)\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 145, in cv2_extract_frames\n    num_frames = int( fps * (video.get(7) // video_fps - discard_begin - discard_end) )\nZeroDivisionError: float floor division by zero\n"
},
{
    "video_path": "OpenDV-YouTube/videos/takemytripdotcom/-GrFwuiFqbc.mp4",
    "problem": "float floor division by zero",
    "action": "skipped",
    "details": "Traceback (most recent call last):\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 41, in extract_frames\n    cv2_extract_frames(video_path, output_dir, fps, discard_begin, discard_end, exception_file)\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 145, in cv2_extract_frames\n    num_frames = int( fps * (video.get(7) // video_fps - discard_begin - discard_end) )\nZeroDivisionError: float floor division by zero\n"
},
{
    "video_path": "OpenDV-YouTube/videos/Walk_East/-X_lyIV76Ek.mp4",
    "problem": "float floor division by zero",
    "action": "skipped",
    "details": "Traceback (most recent call last):\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 41, in extract_frames\n    cv2_extract_frames(video_path, output_dir, fps, discard_begin, discard_end, exception_file)\n  File \"<path>/DriveAGI/opendv/utils/frame_extraction.py\", line 145, in cv2_extract_frames\n    num_frames = int( fps * (video.get(7) // video_fps - discard_begin - discard_end) )\nZeroDivisionError: float floor division by zero\n"
},
.
.
.

All videos seem to have the .mp4 format, did you face this issue while extracting as well?

Many thanks

[GihhArwtw]

hi @aminebdj
sorry for the late response.
Could you please check whether these videos you mentioned truly exist? You may refer to the download_exceptions.txt that will be automatically generated in the opendv root of the codebase.
opencv-python will return 0 if the video does not exist.
I am also working on a script to check whether the downloading is truly successful or not. I'll keep you updated.

[GihhArwtw]

hi @aminebdj
A possible cause for the issue is that the metadata of these mp4 files are fragmented. You may refer to error reading header in FFMPEG and OPENCV for solutions. I am currently working on a update based on the solution above.

[GihhArwtw]

hi @aminebdj
We just updated a version to get the frame rate from ffmpeg when cv2 is not working.
For details, you can refer to implementation details.

NOTE: You are recommended to use ffmpeg<=3.4.9, otherwise fragmented metadata may not be handled successfully.