I want to downscale user input images (jpeg) using HTML5 Canvas / javascript before sending them to server. The goal is to limit image resolution to 1000×1000 pixels and possibly make a thumbnail. But the output images have too much grain / looks too sharp. Looking for a way to produce good quality images.

I’m currently working on a project where I need to convert the colors depending on how many elements that array has (let say if there are 4 elements in array then it will convert into 4 color pattern). and textureFile is a file to place on the image itself, so it is like multiply effect on Photoshop. It places image, but problem is with the rotation. Image should be a tiled knitting, but I get weird result.

I have used the wheel of fortune code by Roko C. Buljan from here: how to draw a wheel of fortune?

I am getting an uncaught promise error from the following code. Does anyone have an idea how should I resolve this error?

I am creating one progress bar using Html5 Canvas, Where i need to show the progress bar based on provided value. Now user set some value and based on it the progress bar should complete the progress.

I tried developing a graph drawing web app using a canvas which includes animations for lines as this:

When drawing lines with ctx. linewidth greater than 1, the performance of js canvas is very poor. For example, if there are 5000 points and ctx. linewidth=1, the performance is good. If it is greater than 1, it will be particularly sluggish. How to optimize the process to avoid lag? Is there any other drawing method.

main.js: