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It takes 2 frames to load one image

The experiment can run, however, sometimes it takes 2 frames to load one image. I observed that the lower part of image appears first, then the upper part.

10.9736 ERROR avbin.dll failed to load. Try importing psychopy.visual
as the first library (before anything that uses scipy)
and make sure that avbin is installed.
22.0467 WARNING Framebuffer object (FBO) not supported on this graphics card

OS (e.g. Win10): Win10
PsychoPy version (e.g. 1.84.x): 1.85.6
Standard Standalone? (y/n) If not then what?: y
**graphics card: Intel HD 620
**What are you trying to achieve?:**Present images fluently

To “load” one image? Yes, it could take that long to load from disk, depending on how many pixels are in the image. That’s just the nature of images and computers. That’s why you should load the image in a static period

As Jon notes, loading an image from disk takes finite time, which can easily exceed a single screen refresh interval. But what you are describing is a different issue (and hence why we need to be very precise with terminology). Getting an image from a file on disk takes a relatively long time, but after that has been done, drawing it to the screen buffer is almost instantaneous in comparison. It may be quite a few milliseconds later that it will actually appear on screen (at the time of the next screen refresh), but the entire image will be drawn during that screen update. If it looks like it is occurring over two updates, then the issue is that your graphics card is not set to use double buffering and to sync with the vertical refresh rate, things that PsychoPy relies upon.

We don’t recommend using PsychoPy under Windows with Intel integrated graphics (as opposed to a dedicated graphics card). But if you must, download the latest driver for that card directly from Intel (don’t rely on the one provided by Windows). And then check its settings for things like double buffering and v sync (both things you should understand if you are running visual experiments).

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I followed this suggestion and found it necessary, but not sufficient to resolve the problem.

It turned out that this machine has two graphics cards, one Intel and the other AMD.
I set python.exe to high performance in the AMD setting, then the image can be drawn in one frame.

Surprisingly, the warning didn’t disappear.

Thank you!