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MovieStim2 and MovieStim3 - Codec

Hi all,
I am creating an experiment in which I will show several videos from different sources. At this point I tested it by using moviestim2 and moviestim3 and they both work fine. However, I realised that the same videos are being shown in different qualities in moviestim2 and moviestim3. I am guessing that this is a codec issue.
Do you have any idea how can I specify which codec to use when displaying my videos using moviestim2 and 3?
Thanks in advance for any ideas!

Someone may come through with a more helpful answer, but I want to make sure you understand the codec is something inherent to the file: whoever made or reformatted the video chose the codec, it’s not something decided when reading the file (for example, when psychopy plays the movie).

It is true that different applications are better than others at reading some codecs. Regarding this issue someone else will have to tell us if there are formats psychopy doesn’t handle well. EDIT And actually, now that I think of it, sometimes the wrong codec is used to read a video, which will cause problems, so your question is in fact a good one.

The world of video containers/codecs/formats (not all the same thing) is very complex, be forewarned. If you need to reformat a video, a good user friendly application is handbrake. Ffmpeg is an excellent, but quite complex, option.

But in your case, to better answer your question you would have to tell us what formats are doing well, and which ones not. But my question is, why are you using both moviestim2 and moviestim3? Which one is working better, and why not just use that one?

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Hi again,
Thanks for your answer.
I am cutting some video clips from movies and therefore I have the chance to choose the codec when I do the encoding. I was thinking if I can choose the same codec on VLC (or If I can set it using moviestim) then I can minimize the chance of error.

Regarding your question, eventually I want to use moviestim3 but as far as I understand moviestim3 uses movie.py and downloads some packages automatically from the internet when it is called for the first time. When I wanted to use moviestim3 in the lab computers it could’t complete this process since they are not connected to the internet and the person who can give me access was on holidays (my institute has very strict IT rules unfortunately). Anyways, I had to use moviestim2 for a while which seems to work except that it uses some other codec (I guess) and some videos are displayed with artifacts.
I still want to learn if there is a way to specify which codec to use and would really appreciate if you can give me some ideas.

One more question:
My institute is not giving me full internet access. Therefore, I need to know from where exactly moviestim3 downloads ffmpeg and request access for this server. Does anyone have information about that?