iphone相机视图上实时水印图像

Question

提前特别感谢...... 我是 iphone 软件开发的初学者。

只是在寻找如何使用 cocoa 以编程方式将实时水印图像添​​加到相机视图中。不是一步一步地寻找（虽然那会很棒），而是或多或少地寻找我应该从哪里开始寻找学习方法。是否有为此开发的框架。想要使用 XCode 框架的 Objective-C 原生的东西，因为我想最终在 iPhone 上试一试。任何帮助都会很棒。

Answer 1

更新：这是我关于如何将此叠加视图放在相机动画下的另一个答案：camera overlay view - just for preview?

Helo Rajendra！

我创建了一个简单的基于 Window 的 iPhone OS 应用程序，为您提供一个非常简单的示例，说明应该如何以及如何使用相机拍摄照片、在相机模式下叠加视图、调整大小和合并图像。这个项目实际上只有 AppDelegate 头文件和实现文件，可以很容易地在 XCode 中重现。

这是头文件：

//
//  CameraWatermarkAppDelegate.h
//  CameraWatermark
//
//  Created by Ivan Karpan on 1/16/10.
//  Copyright __MyCompanyName__ 2010. All rights reserved.
//

#import <UIKit/UIKit.h>


@interface CameraWatermarkAppDelegate : NSObject < UIApplicationDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate > {
    UIImageView *imageView;
    UIViewController *viewController;
    UIWindow *window;
}

@property (nonatomic, retain) UIImageView *imageView;
@property (nonatomic, retain) UIViewController *viewController;
@property (nonatomic, retain) IBOutlet UIWindow *window;


@end

这是实现文件：

//
//  CameraWatermarkAppDelegate.m
//  CameraWatermark
//
//  Created by Ivan Karpan on 1/16/10.
//  Copyright __MyCompanyName__ 2010. All rights reserved.
//

#import "CameraWatermarkAppDelegate.h"


const float WATERMARK_ALPHA = 0.5;


@implementation CameraWatermarkAppDelegate

@synthesize imageView, viewController, window;


- (void)applicationDidFinishLaunching:(UIApplication *)application {
    self.viewController = [[UIViewController new] autorelease];
    viewController.view.backgroundColor = [UIColor blackColor];

    // An image view to save to (and therefore display) the captured image
    self.imageView = [[UIImageView new] autorelease];
    imageView.frame = viewController.view.frame;
    [viewController.view addSubview:imageView];

    [window addSubview:viewController.view];

    UIImagePickerController *anImagePickerController = [UIImagePickerController new];
    anImagePickerController.delegate = self;
    anImagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;

    {// This block of code is only needed in case you want your watermark to be displayed also during the shooting process
        UIImageView *anImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Watermark.png"]];
        anImageView.alpha = WATERMARK_ALPHA;
        anImageView.contentMode = UIViewContentModeTopLeft;
        anImageView.frame = viewController.view.frame;
        anImagePickerController.cameraOverlayView = anImageView;
        [anImageView release];
    }

    // From the very beginning we simply present the image picker controller
    [viewController presentModalViewController:anImagePickerController animated:NO];
    [anImagePickerController release];
}


- (void)dealloc {
    [imageView release];
    [viewController release];
    [window release];
    [super dealloc];
}

#pragma mark UIImagePickerControllerDelegate

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    UIGraphicsBeginImageContext(CGSizeMake(320, 480));
    // This is where we resize captured image
    [(UIImage *)[info objectForKey:UIImagePickerControllerOriginalImage] drawInRect:CGRectMake(0, 0, 320, 480)];
    // And add the watermark on top of it
    [[UIImage imageNamed:@"Watermark.png"] drawAtPoint:CGPointMake(0, 0) blendMode:kCGBlendModeNormal alpha:WATERMARK_ALPHA];
    // Save the results directly to the image view property
    imageView.image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    // Dismiss the image picker controller and look at the results
    [picker dismissModalViewControllerAnimated:YES];
}


@end

我希望这将成为您的起点。