Nielk1

I have a lot of items in my library right now (27907 though I am cleaning it out a bit) and I have some major slowdown as expected. I'm not sure where the slowdown is though so I can't make a specific suggestion. If the problem is in parsing the library data, I'd suggest placing that operation in a thread so the UI does not freeze while it is working. This would also allow for canceling of the thread if the user changes their selection while it's busy. You would need to get a nice mutex lock on the library data though which could get messy if you haven't already threaded that. If the issue is the customized ListView my only guess would be you're not using virtual mode. Given the speed of the program overall I presume you are using virtual mode though, so that's likely not the issue.

Theoretically this is ghost borders caused by anti-aliasing when scaling. This page describes a solution that involves tricking the scaler's anti-aliaser using flipped tiling and drawing the image scaled into a waiting canvas: https://blog.mariusschulz.com/2014/05/28/preventing-ghost-borders-when-resizing-images-with-system-drawing The important code fragment if the site goes down: using (var graphics = Graphics.FromImage(resizedImage)) { graphics.InterpolationMode = InterpolationMode.HighQualityBicubic; var attributes = new ImageAttributes(); attributes.SetWrapMode(WrapMode.TileFlipXY); var destination = new Rectangle(0, 0, targetWidth, targetHeight); graphics.DrawImage(image, destination, 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, attributes); }