摄像头打开时进行截图-iOS

我正在使用AR应用程序，在我的项目中使用苹果的AVCam示例代码。 我正在尝试使用我在这里find的以下方法截取屏幕截图，但它们并不适合我。 有什么build议么？ 谢谢。

- (UIImage *) screenshot { UIWindow *window = [UIApplication sharedApplication].keyWindow; if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) UIGraphicsBeginImageContextWithOptions(window.bounds.size, NO, [UIScreen mainScreen].scale); else UIGraphicsBeginImageContext(window.bounds.size); [self.view.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); NSData * data = UIImageJPEGRepresentation(image, 1.0); return [UIImage imageWithData:data]; } - (UI Image*)screenshot2 { // On iOS prior to 4, fall back to use UIGraphicsBeginImageContext CGSize imageSize = [[UIScreen mainScreen] bounds].size; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0); else UIGraphicsBeginImageContext(imageSize); CGContextRef context = UIGraphicsGetCurrentContext(); // Iterate over every window from back to front for (UIWindow *window in [[UIApplication sharedApplication] windows]) { if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen]) { // -renderInContext: renders in the coordinate space of the layer, // so we must first apply the layer's geometry to the graphics context CGContextSaveGState(context); // Center the context around the window's anchor point CGContextTranslateCTM(context, [window center].x, [window center].y); // Apply the window's transform about the anchor point CGContextConcatCTM(context, [window transform]); // Offset by the portion of the bounds left of and above the anchor point CGContextTranslateCTM(context, -[window bounds].size.width * [[window layer] anchorPoint].x, -[window bounds].size.height * [[window layer] anchorPoint].y); // Render the layer hierarchy to the current context [[window layer] renderInContext:context]; // Restore the context CGContextRestoreGState(context); } } // Retrieve the screenshot image UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return image; } 

Answer 1

该代码不起作用，因为CALayer的renderInContext不会呈现来自相机的内容。

请参阅以下参考： https ： //developer.apple.com/library/ios/qa/qa1714/_index.html

如上面的链接所述，您可以：
1）使用相关的AVFoundation API（ https://developer.apple.com/library/ios/qa/qa1702/_index.html#//apple_ref/doc/uid/DTS40010192 ）捕获相机的内容
2），然后将捕获的图像绘制到您呈现UIKit元素的graphics上下文中。