What does the following error message mean?

[yxchng]

OpenCV Error: Assertion failed (image->depth == 8) in writeFrame, file /home/yxchng/OpenCV/modules/videoio/src/cap_ffmpeg.cpp, line 272

I follow the VideoWriter example but I couldnt save a video. Instead I got the above error.

[shrubb]

It's an error similar to this one. Be careful about image depth (RGB or grayscale) and the type of video codec you use. Try different options.

[yxchng]

@shrubb I tried using XVID, MPEG, H264. All don't work. Image depth is rgb.

If i can do imwrite why i cant do videowriter.write?

[shrubb]

Because OpenCV works this way -- every function has constraints on the types of input matrices (images). imwrite has nothing to do with VideoWriter.write, they are completely different functions with different constraints.

Image depth can't be RGB. This is the channel layout. Depth is the number of bits per pixel. As far as I remember, VideoWriter typically requires 8 bit per channel pixel. So it should work with ByteTensors.

[hahakid]

https://stackoverflow.com/questions/38880740/python-opencv-cv2-videowriter-error
add np.uint8(your_variable) before write