Tkinter fast Image display?

Question

I'm working on a basic Tkinter image viewer. After fiddling with a lot of the code, I have two lines which depending on the operation that triggered the refresh are 50-95% of the execution time.

self.photo = ImageTk.PhotoImage(resized)
self.main_image.config(image=self.photo)

Is there a faster way to display a PIL/Pillow Image in Tkinter?

Answer 1

I would recommend testing the 4000x4000 images you're concerned about (which is twice the resolution of a 4K monitor). Use a Google advanced search to find such images, or use a photo/image editor to tile an image you already have. Since I don't think many people would connect a 4K (or better) monitor to a low-end computer, you could then test the difference between scaling down a large image and simply displaying it, so if most of the work is in resizing the image you don't have to worry as much about that part.

Next, test the individual performance of each of the two lines you posted. You might try implementing some kind of intelligent pre-caching, which many programs do: resize and create the next photo as the user is looking at the current one, then when the user goes to the next image all the program has to do is reconfigure self.main_image . You can see this general strategy at work in the standard Windows Photo Viewer, which responds apparently instantaneously to normal usage, but can have noticeable lag if you browse too quickly or switch your browsing direction.

Also ask your target userbase what sort of machines they're using and how large their images are. Remember that reasonable "recommended minimum specs" are acceptable.

Most importantly, keep in mind that the point of Python is clear, concise, readable code. If you have to throw away those benefits for the sake of performance, you might as well use a language that places more emphasis on performance, like C. Make absolutely sure that these performance improvements are an actual need, rather than just "my program might lag! I have to fix that."