Question

我有一个使用AVFoundation设置相机的初学者项目，它运行得很好。现在我需要将Camera机制转换为GPUImage。我在两个项目中使用了相同的焦点和曝光方法（在AVFoundation项目中工作得很好）但在GPUImage项目中它没有正确聚焦而且总是错误。

请注意，应用过滤器对所有过滤器都是相同的

示例： 在屏幕的右上角，您可以看到羊肉。这就是聚焦+曝光的方式。

设置GPU：

stillCamera = GPUImageStillCamera(sessionPreset: AVCaptureSessionPreset640x480, cameraPosition: .Front)
    CorrectPosition =  AVCaptureDevicePosition.Front
    stillCamera!.outputImageOrientation = .Portrait;
    stillCamera?.horizontallyMirrorFrontFacingCamera = true
    filter = GPUImageFilter()
    stillCamera?.addTarget(filter)
    filter?.addTarget(self.view as! GPUImageView)
    (self.view as! GPUImageView).fillMode = GPUImageFillModeType.init(2)

TouchBegan方法：

   override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        var tap : CGPoint!
        if let touch = touches.first as UITouch! {
            tap = touch.locationInView(self.view)
        }
        let device: AVCaptureDevice! = self.stillCamera?.inputCamera!
        var error: NSError? = nil
        do {
            try device.lockForConfiguration()
            if device.focusPointOfInterestSupported && device.isFocusModeSupported(AVCaptureFocusMode.AutoFocus){
                device.focusMode = AVCaptureFocusMode.AutoFocus
                device.focusPointOfInterest = tap
            }
            if device.exposurePointOfInterestSupported && device.isExposureModeSupported(AVCaptureExposureMode.AutoExpose){
                device.exposurePointOfInterest = tap
                device.exposureMode = AVCaptureExposureMode.AutoExpose
            }
            device.subjectAreaChangeMonitoringEnabled = monitorSubjectAreaChange
            device.unlockForConfiguration()
        } catch let error1 as NSError {
            error = error1
            print(error)
        } catch {
            fatalError()
        }
    }

有什么想法吗？

Answer 1

您可能遇到的问题是device.focusPointOfInterest的{{1}}和x需要位于y范围内，其中[0;1]点是相机的左下角和(0,0)是右上角，而您在视图的框架坐标系中传递了tap的坐标。

您唯一需要做的就是将水龙头的坐标转换为您的相机点。但请注意，相机可以有不同的填充模式。

以下是我如何进行转换（抱歉为Objective-C代码，但主要是简单的数学运算）：

(1,1)

以及方法的实施：

CGPoint tapPoint = [gestureRecognizer locationInView:cameraView];

CGPoint pointOfInterest = [HBFocusUtils convertToPointOfInterestFromViewCoordinates:tapPoint inFrame:cameraView.bounds withOrientation:self.currentOrientation andFillMode:cameraView.fillMode mirrored:currentVideoCamera == frontVideoCamera];

[HBFocusUtils setFocus:pointOfInterest forDevice:currentVideoCamera.inputCamera];

Answer 2

<强> SWIFT

1）首先在Objective-C中创建HBFocusUtils类

2）桥文件中的#import "HBFocusUtils.h"

//Focus on tap
//============
let tap = UITapGestureRecognizer(target: self, action: Selector("tapOnFocus:"))
tap.delegate = self
filterView.addGestureRecognizer(tap)

func tapOnFocus(gestureRecognizer: UITapGestureRecognizer? = nil)
    {
        let tapPoint = (gestureRecognizer?.locationInView(filterView))! as CGPoint
        let pointOfInterest = HBFocusUtils.convertToPointOfInterestFromViewCoordinates(tapPoint, inFrame: filterView.bounds, withOrientation: .Portrait, andFillMode:
            GPUImageFillModeType.init(1), mirrored: true)
        HBFocusUtils.setFocus(pointOfInterest, forDevice: stillCamera.inputCamera)
    }

<强> HBFocusUtils.h

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#import "GPUImageView.h"

@interface HBFocusUtils : NSObject

+ (CGPoint)convertToPointOfInterestFromViewCoordinates:(CGPoint)viewCoordinates inFrame:(CGRect)frame withOrientation:(UIDeviceOrientation)orientation andFillMode:(GPUImageFillModeType)fillMode mirrored:(BOOL)mirrored;
+ (void)setFocus:(CGPoint)focus forDevice:(AVCaptureDevice *)device;
@end

的 HBFocusUtils.m

#import "HBFocusUtils.h" @implementation HBFocusUtils + (CGPoint)convertToPointOfInterestFromViewCoordinates:(CGPoint)viewCoordinates inFrame:(CGRect)frame withOrientation:(UIDeviceOrientation)orientation andFillMode:(GPUImageFillModeType)fillMode mirrored:(BOOL)mirrored; { CGSize frameSize = frame.size; CGPoint pointOfInterest = CGPointMake(0.5, 0.5); if (mirrored) { viewCoordinates.x = frameSize.width - viewCoordinates.x; } if (fillMode == kGPUImageFillModeStretch) { pointOfInterest = CGPointMake(viewCoordinates.y / frameSize.height, 1.f - (viewCoordinates.x / frameSize.width)); } else { CGSize apertureSize = CGSizeMake(CGRectGetHeight(frame), CGRectGetWidth(frame)); if (!CGSizeEqualToSize(apertureSize, CGSizeZero)) { CGPoint point = viewCoordinates; CGFloat apertureRatio = apertureSize.height / apertureSize.width; CGFloat viewRatio = frameSize.width / frameSize.height; CGFloat xc = .5f; CGFloat yc = .5f; if (fillMode == kGPUImageFillModePreserveAspectRatio) { if (viewRatio > apertureRatio) { CGFloat y2 = frameSize.height; CGFloat x2 = frameSize.height * apertureRatio; CGFloat x1 = frameSize.width; CGFloat blackBar = (x1 - x2) / 2; if (point.x >= blackBar && point.x <= blackBar + x2) { xc = point.y / y2; yc = 1.f - ((point.x - blackBar) / x2); } } else { CGFloat y2 = frameSize.width / apertureRatio; CGFloat y1 = frameSize.height; CGFloat x2 = frameSize.width; CGFloat blackBar = (y1 - y2) / 2; if (point.y >= blackBar && point.y <= blackBar + y2) { xc = ((point.y - blackBar) / y2); yc = 1.f - (point.x / x2); } } } else if (fillMode == kGPUImageFillModePreserveAspectRatioAndFill) { if (viewRatio > apertureRatio) { CGFloat y2 = apertureSize.width * (frameSize.width / apertureSize.height); xc = (point.y + ((y2 - frameSize.height) / 2.f)) / y2; yc = (frameSize.width - point.x) / frameSize.width; } else { CGFloat x2 = apertureSize.height * (frameSize.height / apertureSize.width); yc = 1.f - ((point.x + ((x2 - frameSize.width) / 2)) / x2); xc = point.y / frameSize.height; } } pointOfInterest = CGPointMake(xc, yc); } } return pointOfInterest; } + (void)setFocus:(CGPoint)focus forDevice:(AVCaptureDevice *)device { if ([device isFocusPointOfInterestSupported] && [device isFocusModeSupported:AVCaptureFocusModeAutoFocus]) { NSError *error; if ([device lockForConfiguration:&error]) { [device setFocusPointOfInterest:focus]; [device setFocusMode:AVCaptureFocusModeAutoFocus]; [device unlockForConfiguration]; } } if ([device isExposurePointOfInterestSupported] && [device isExposureModeSupported:AVCaptureExposureModeAutoExpose]) { NSError *error; if ([device lockForConfiguration:&error]) { [device setExposurePointOfInterest:focus]; [device setExposureMode:AVCaptureExposureModeAutoExpose]; [device unlockForConfiguration]; } } } @end

GPUImage - 点击和曝光无法正常工作 - 缺少某些东西？

2 个答案: