[英]Load image from photo library
If you want to load an image from photo library, you have to use UIImagePickerController class. 如果要从照片库加载图像,则必须使用UIImagePickerController类。 Refer this Link
引用此链接
To convert image form UIImagePickerController
to black and white you can use this code: 要将图像形式的
UIImagePickerController
转换为黑白,可以使用以下代码:
UIImage *originalImage = [info objectForKey:UIImagePickerControllerOriginalImage]; // this image we get from UIImagePickerController
CGColorSpaceRef colorSapce = CGColorSpaceCreateDeviceGray();
CGContextRef context = CGBitmapContextCreate(nil, originalImage.size.width, originalImage.size.height, 8, originalImage.size.width, colorSapce, kCGImageAlphaNone);
CGContextSetInterpolationQuality(context, kCGInterpolationHigh);
CGContextSetShouldAntialias(context, NO);
CGContextDrawImage(context, CGRectMake(0, 0, originalImage.size.width, originalImage.size.height), [originalImage CGImage]);
CGImageRef bwImage = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSapce);
UIImage *resultImage = [UIImage imageWithCGImage:bwImage]; // This is result B/W image.
CGImageRelease(bwImage);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.