相机预览不填满屏幕

Posted 2023-03-12

【中文标题】相机预览不填满屏幕

【英文标题】：Camera Preview does not fill screen

【发布时间】：2012-10-03 10:45:14

【问题描述】：

这就是我在 iPad3 中以横向模式设置相机预览的方式

- (void)viewDidAppear:(BOOL)animated

AVCaptureSession *session = [[AVCaptureSession alloc] init];
session.sessionPreset = AVCaptureSessionPreset640x480;

CALayer *viewLayer = self.vImagePreview.layer;

NSLog(@"viewLayer = %@", viewLayer);

AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];

captureVideoPreviewLayer.frame = self.vImagePreview.bounds;
[self.vImagePreview.layer addSublayer:captureVideoPreviewLayer];

AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

NSError *error = nil;
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
if (!input) 
    // Handle the error appropriately.
    NSLog(@"ERROR: trying to open camera: %@", error);

[session addInput:input];

stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
[stillImageOutput setOutputSettings:outputSettings];

[session addOutput:stillImageOutput];

[session startRunning];

在情节提要中，我将视图设置为填满整个屏幕，但它最终看起来像这样：

此外，图像也旋转了 90 度。如何更改此设置，以便让相机预览充满整个屏幕？

谢谢。

【参考方案1】：

旋转图层：

    switch (self.interfaceOrientation)
    
     case UIInterfaceOrientationLandscapeRight:
       [captureVideoPreviewLayer setAffineTransform:CGAffineTransformMakeRotation(-M_PI / 2)];
       break;
     case UIInterfaceOrientationLandscapeLeft:
       [captureVideoPreviewLayer setAffineTransform:CGAffineTransformMakeRotation(M_PI / 2)];
       break;
    

[self.vImagePreview.layer addSublayer:captureVideoPreviewLayer]; 

【讨论】：

这确实有效。但是我最终使用了 captureVideoPreviewLayer.orientation = UIInterfaceOrientationLandscapeLeft;谢谢！

请注意 AVCaptureVideoPreviewLayer.orientation 被标记为已弃用