![]() The following code loops over all the emojis within the image file and extract them, one by one. ![]() Var position = ( x + imageData.width * y ) * 4, data = imageData.data Pixels can be retrieved using their position within the image: The structure returned by getImagedata is an array which contains, for each pixel, its R, G, B and A colour components. Var imageData = ctx.getImageData(0,0,canvas.width,canvas.height) Īn image is loaded asynchronously its load handler creates a hidden canvas, draws the image onto it and gets its data. Var canvas = document.createElement('canvas') Ĭtx.drawImage(image,0,0,canvas.width,canvas.height) The code below shows how this technique works. This method is available only on a canvas, so it is necessary to draw the emoji map onto a canvas. Reading the pixels of an image is possible using getImageData. This very technique can also be used to create emoji animations. The next pages of this tutorial will show how this has been done in JavaScript. The most expensive part of this technique is checking each pixels against every emoji. To speed up the emojification process, the average colour of each emoji is calculated and stored into a JSON file for fast retrieving. You can see the difference this makes in the comparison box below. To compensate for this, emojis are slightly rotated and moved around. This scaling operation automatically merges colours together, so that one pixel of the thumbnail will correspond to one emoji. It’s fast and reliable, but creates very regular mosaics. This is the bare minimum requires to create an emoji mosaic. The first step is achieved by resizing the original image to a smaller size.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |