New metatag in output file: Handler Vendor ID: Apple

Python
1

I have to process a video file and get wrid of the metadata. For this i use the cv2 python library to convert an input file to a new mp4 video. I use an ExIf metadata reader and have noticed that the output files always have this metadata tag Handler Vendor ID: Apple

This tag does not exist in the input file. I have tried my scirpt on several machines and always get an output that contains this metatag. Whats the reason for this? Is there a Apple software component used in the open cv library?

import cv2

Open a video file

cap = cv2.VideoCapture(r"C:\Users\MrX\OneDrive Ltd\Desktop\documents\20240904_114857.mp4")

Set up the video writer with the same properties as the original

fourcc = cv2.VideoWriter_fourcc(*‘mp4v’)
output_file_path = r"C:\Users\MrX\OneDrive\documents\video6.mp4"
out = cv2.VideoWriter(output_file_path, fourcc, 20.0, (int(cap.get(3)), int(cap.get(4))))

while cap.isOpened():
ret, frame = cap.read()
if ret:
# Write the frame to the new video file
out.write(frame)
else:
break

2

how do you even get this information ?

which is ? it’s probably making this up, similar to DPI and all other exif sillyness…

just to make sure, please specify, which backends are used for reading / writing
(ffmpeg ? gstreamer ?)

opencv for sure does not write any exif tags to videos
(or even images)

3

Im using ExifTool by Phil Harvey. https://exiftool.org/

Tried it also with https://exif.tools/. The results are the same. Always the same…Handler Vendor ID: Apple

4

i’m still quite sure, they ‘invent’ this meta data, if it’s not present in the actual file.

still, why is this relevant for you ? it’s really not needed for computer-vision.

last, opencv is quite the wrong choice to recode video files, rather learn to use ffmpeg or gstreamer directly, please.