Question

我需要iOS相机在没有用户输入的情况下拍照。我该怎么做呢？到目前为止，这是我的代码：

-(void)initCapture{
    AVCaptureDeviceInput *newVideoInput = [[AVCaptureDeviceInput alloc] init];

    AVCaptureStillImageOutput *newStillImageOutput = [[AVCaptureStillImageOutput alloc] init];

    NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:
                                AVVideoCodecJPEG, AVVideoCodecKey,
                                nil];


    [newStillImageOutput setOutputSettings:outputSettings];


    AVCaptureSession *newCaptureSession = [[AVCaptureSession alloc] init];

    if ([newCaptureSession canAddInput:newVideoInput]) {
        [newCaptureSession addInput:newVideoInput];
    }
    if ([newCaptureSession canAddOutput:newStillImageOutput]) {
        [newCaptureSession addOutput:newStillImageOutput];
    }
    self.stillImageOutput = newStillImageOutput;
}

我还需要添加什么，以及从哪里开始？我不想拍摄视频，只拍摄一张静止图片。另外，之后如何将图像转换为UIImage？感谢

Answer 1

https://developer.apple.com/library/mac/documentation/AVFoundation/Reference/AVCaptureSession_Class/Reference/Reference.html

了解如何在没有用户输入的情况下拍摄照片的AVCaptureSession。您需要将AVCaptureDevice添加到会话中。

Answer 2

您已获得AVCaptureStillImageOutput，stillImageOutput。此外，您需要将捕获会话存储在以后可以获取的位置。称之为self.sess。然后：

AVCaptureConnection *vc = 
    [self.stillImageOutput connectionWithMediaType:AVMediaTypeVideo];
[self.sess startRunning];
[self.stillImageOutput captureStillImageAsynchronouslyFromConnection:vc
                                          completionHandler:
 ^(CMSampleBufferRef buf, NSError *err) {
     NSData* data = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:buf];
     UIImage* im = [UIImage imageWithData:data];
     dispatch_async(dispatch_get_main_queue(), ^{
         UIImageView* iv = [[UIImageView alloc] initWithFrame:someframe];
         iv.contentMode = UIViewContentModeScaleAspectFit;
         iv.image = im;
         [self.view addSubview: iv];
         [self.iv removeFromSuperview]; // in case we already did this
         self.iv = iv;
         [self.sess stopRunning];
     });
 }];

Answer 3

正如@Salil所说，苹果的官方AVFoundation非常有用，看看它就能理解主要概念。然后，您可以下载示例代码以了解如何实现目标。

Here is the sample code使用预览图片拍摄静止图像。

如何使用AVFoundation强制iOS相机以编程方式拍照？

3 个答案: