videoreader doesn't accurately take frames from wmv file

I'm using videoreader to get a .wmv file in matlab, then I use readframes.

Opening my wmv video in VLC or any other video player, it shows it in high quality. The edges of objects are smooth and there are no big pixels visible.

On the other hand in matlab, the frames taken from the video - although having the same pixel resolution size as the video - are in worse quality. It looks pixelated.

I want to keep the quality of the frames as best as possible. What do I do? So far my guess is to maybe convert wmv to avi, or use opencv or anything else than "videoreader".

[Saurabh]

Hi @sdfjkskjfs,

Would it be possible to share a demo video file, so that I can investigate further, and an example code with the MATLAB version that is being used here.

Thank You,

[Walter Roberson]

I wonder if you need to readFrame() with the 'native' option ?

[sdfjkskjfs]

@Walter Roberson no change, thank you though

[sdfjkskjfs]

@Saurabh

Matlab R2024b on Windows 10 Pro

 videoFile = 'C:\... .wmv';
 videoObj = VideoReader(videoFile);

 frame = readFrame(videoObj);
 imshow(frame);

[Walter Roberson]

I do not immediately see a difference in those two images, except that one is larger than the other.

[sdfjkskjfs]

@Walter Roberson zoomed in on the sphere it's more apparent.

[DGM]

I get equally blocky results from both VLC and Totem:

It's really hard to see the banding against this awful white background, but it's the same.

[sdfjkskjfs]

@DGM can you please check again, if the pixelation is visible, using the interactive zoom feature of VLC?

[DGM]

The interactive zoom does some sort of interpolated upscaling. It's not the actual resolution of the information in the file.

[sdfjkskjfs]

@DGM Thank you! That was the key information. Checking out all frames from the video saved via matlab, it seems that only the first few frames (~10) are of bad quality. I think it has nothing to do with the vlc zoom feature.

Solved