pixel

I know this is a common question and there are a lot of answers of this question. I've used some of this. Although many of them are the same. But the sad thing for me is that none of them worked for me. The following codes i've used till now. -(void)getRGBAsFromImage:(UIImage*)image atX:(int)xx andY:(int)yy { // First get the image into your data buffer CGImageRef imageRef = [image CGImage]; NSUInteger width = CGImageGetWidth(imageRef); NSUInteger height = CGImageGetHeight(imageRef); CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); unsigned char *rawData = (unsigned char*) calloc

My question is if I have a Lion image just I want to change the color of the lion alone not the background color. For that I referred this SO question but it turns the color of whole image. Moreover the image is not looking great. I need the color change like photoshop. whether it is possible to do this in coregraphics or I have to use any other library. EDIT : I need the color change to be like iQuikColor app See answers below instead. Mine doesn't provide a complete solution. Here is the sketch of a possible solution using OpenCV: Convert the image from RGB to HSV using cvCvtColor (we only

The HTML5 Canvas has no method for explicitly setting a single pixel. It might be possible to set a pixel using a very short line, but then antialising and line caps might interfere. Another way might be to create a small ImageData object and using: context.putImageData(data, x, y) to put it in place. Can anyone describe an efficient and reliable way of doing this? There are two best contenders: Create a 1×1 image data, set the color, and putImageData at the location: var id = myContext.createImageData(1,1); // only do this once per page var d = id.data; // only do this once per page d[0] = r;

准备尝试用vue制作一个手机端的可视化应用 全局安装vue命令 cnpm install -g @vue/cli 创建项目 进入项目存放目录新建项目 vue create [project name]cd [project name] 安装插件 这里我安装了一个代码校验、以及router、vuex vue add @vue/eslint vue add router vue add vuex 全局CLI配置 在以往的版本中都会有个config文件作为全局配置，但是当前的版本需要自己添加 vue.config.js ，只要在package.json同级目录下（即根目录）创建 const path = require("path"); function resolve(dir) { return path.join(__dirname, "./", dir); } module.exports = { chainWebpack: config => { // 为src下文件配别名，不使用相对路径 config.resolve.alias .set("@", resolve("src")) .set("assets", resolve("src/assets")) .set("components", resolve("src/components")) .set("views",

I am trying to develop a small application. In it, I need to detect the color of a pixel within an UIView. I have a CGPoint defining the pixel I need. The colors of the UIView are changed using CoreAnimation. I know there are some complex ways to extract color information from UIImages. However I couldn't find a solution for UIViews. In Pseudo-Code I am looking for something like pixel = [view getPixelAtPoint:myPoint]; UIColor *mycolor = [pixel getColor]; Any input greatly appreciated. Louis Gerbarg It is pretty horrible and slow. Basically you create a bitmap context with a backing store you