30分鐘搞定iOS自定義相機(jī)
最近公司的項(xiàng)目中用到了相機(jī),由于不用系統(tǒng)的相機(jī),UI給的相機(jī)切圖,必須自定義才可以。就花時(shí)間簡(jiǎn)單研究了一下相機(jī)的自定義。
相機(jī)屬于系統(tǒng)硬件,這就需要我們來手動(dòng)調(diào)用iPhone的相機(jī)硬件,分為以下步驟:
1、首先聲明以下對(duì)象
- #import <AVFoundation/AVFoundation.h>
- //捕獲設(shè)備,通常是前置攝像頭,后置攝像頭,麥克風(fēng)(音頻輸入)
- @property (nonatomic, strong) AVCaptureDevice *device;
- //AVCaptureDeviceInput 代表輸入設(shè)備,他使用AVCaptureDevice 來初始化
- @property (nonatomic, strong) AVCaptureDeviceInput *input;
- //輸出圖片
- @property (nonatomic ,strong) AVCaptureStillImageOutput *imageOutput;
- //session:由他把輸入輸出結(jié)合在一起,并開始啟動(dòng)捕獲設(shè)備(攝像頭)
- @property (nonatomic, strong) AVCaptureSession *session;
- //圖像預(yù)覽層,實(shí)時(shí)顯示捕獲的圖像
- @property (nonatomic ,strong) AVCaptureVideoPreviewLayer *previewLayer;
2、初始化各個(gè)對(duì)象
- - (void)cameraDistrict
- {
- // AVCaptureDevicePositionBack 后置攝像頭
- // AVCaptureDevicePositionFront 前置攝像頭
- self.device = [self cameraWithPosition:AVCaptureDevicePositionFront];
- self.input = [[AVCaptureDeviceInput alloc] initWithDevice:self.device error:nil];
- self.imageOutput = [[AVCaptureStillImageOutput alloc] init];
- self.session = [[AVCaptureSession alloc] init];
- // 拿到的圖像的大小可以自行設(shè)定
- // AVCaptureSessionPreset320x240
- // AVCaptureSessionPreset352x288
- // AVCaptureSessionPreset640x480
- // AVCaptureSessionPreset960x540
- // AVCaptureSessionPreset1280x720
- // AVCaptureSessionPreset1920x1080
- // AVCaptureSessionPreset3840x2160
- self.session.sessionPreset = AVCaptureSessionPreset640x480;
- //輸入輸出設(shè)備結(jié)合
- if ([self.session canAddInput:self.input]) {
- [self.session addInput:self.input];
- }
- if ([self.session canAddOutput:self.imageOutput]) {
- [self.session addOutput:self.imageOutput];
- }
- //預(yù)覽層的生成
- self.previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.session];
- self.previewLayer.frame = CGRectMake(0, 64, SCREEN_WIDTH, SCREEN_HEIGHT-64);
- self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
- [self.view.layer addSublayer:self.previewLayer];
- //設(shè)備取景開始
- [self.session startRunning];
- if ([_device lockForConfiguration:nil]) {
- //自動(dòng)閃光燈,
- if ([_device isFlashModeSupported:AVCaptureFlashModeAuto]) {
- [_device setFlashMode:AVCaptureFlashModeAuto];
- }
- //自動(dòng)白平衡,但是好像一直都進(jìn)不去
- if ([_device isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeAutoWhiteBalance]) {
- [_device setWhiteBalanceMode:AVCaptureWhiteBalanceModeAutoWhiteBalance];
- }
- [_device unlockForConfiguration];
- }
- }
根據(jù)前后置位置拿到相應(yīng)的攝像頭:
- - (AVCaptureDevice *)cameraWithPosition:(AVCaptureDevicePosition)position{
- NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
- for ( AVCaptureDevice *device in devices )
- if ( device.position == position ){
- return device;
- }
- return nil;
- }
3、拍照拿到相應(yīng)圖片:
- - (void)photoBtnDidClick
- {
- AVCaptureConnection *conntion = [self.imageOutput connectionWithMediaType:AVMediaTypeVideo];
- if (!conntion) {
- NSLog(@"拍照失敗!");
- return;
- }
- [self.imageOutput captureStillImageAsynchronouslyFromConnection:conntion completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
- if (imageDataSampleBuffer == nil) {
- return ;
- }
- NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
- self.image = [UIImage imageWithData:imageData];
- [self.session stopRunning];
- [self.view addSubview:self.cameraImageView];
- }
4、前后置攝像頭的切換
- - (void)changeCamera{
- NSUInteger cameraCount = [[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo] count];
- if (cameraCount > 1) {
- NSError *error;
- //給攝像頭的切換添加翻轉(zhuǎn)動(dòng)畫
- CATransition *animation = [CATransition animation];
- animation.duration = .5f;
- animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
- animation.type = @"oglFlip";
- AVCaptureDevice *newCamera = nil;
- AVCaptureDeviceInput *newInput = nil;
- //拿到另外一個(gè)攝像頭位置
- AVCaptureDevicePosition position = [[_input device] position];
- if (position == AVCaptureDevicePositionFront){
- newCamera = [self cameraWithPosition:AVCaptureDevicePositionBack];
- animation.subtype = kCATransitionFromLeft;//動(dòng)畫翻轉(zhuǎn)方向
- }
- else {
- newCamera = [self cameraWithPosition:AVCaptureDevicePositionFront];
- animation.subtype = kCATransitionFromRight;//動(dòng)畫翻轉(zhuǎn)方向
- }
- //生成新的輸入
- newInput = [AVCaptureDeviceInput deviceInputWithDevice:newCamera error:nil];
- [self.previewLayer addAnimation:animation forKey:nil];
- if (newInput != nil) {
- [self.session beginConfiguration];
- [self.session removeInput:self.input];
- if ([self.session canAddInput:newInput]) {
- [self.session addInput:newInput];
- self.input = newInput;
- } else {
- [self.session addInput:self.input];
- }
- [self.session commitConfiguration];
- } else if (error) {
- NSLog(@"toggle carema failed, error = %@", error);
- }
- }
- }
5、相機(jī)的其它參數(shù)設(shè)置
- //AVCaptureFlashMode 閃光燈
- //AVCaptureFocusMode 對(duì)焦
- //AVCaptureExposureMode 曝光
- //AVCaptureWhiteBalanceMode 白平衡
- //閃光燈和白平衡可以在生成相機(jī)時(shí)候設(shè)置
- //曝光要根據(jù)對(duì)焦點(diǎn)的光線狀況而決定,所以和對(duì)焦一塊寫
- //point為點(diǎn)擊的位置
- - (void)focusAtPoint:(CGPoint)point{
- CGSize size = self.view.bounds.size;
- CGPoint focusPoint = CGPointMake( point.y /size.height ,1-point.x/size.width );
- NSError *error;
- if ([self.device lockForConfiguration:&error]) {
- //對(duì)焦模式和對(duì)焦點(diǎn)
- if ([self.device isFocusModeSupported:AVCaptureFocusModeAutoFocus]) {
- [self.device setFocusPointOfInterest:focusPoint];
- [self.device setFocusMode:AVCaptureFocusModeAutoFocus];
- }
- //曝光模式和曝光點(diǎn)
- if ([self.device isExposureModeSupported:AVCaptureExposureModeAutoExpose ]) {
- [self.device setExposurePointOfInterest:focusPoint];
- [self.device setExposureMode:AVCaptureExposureModeAutoExpose];
- }
- [self.device unlockForConfiguration];
- //設(shè)置對(duì)焦動(dòng)畫
- _focusView.center = point;
- _focusView.hidden = NO;
- [UIView animateWithDuration:0.3 animations:^{
- _focusView.transform = CGAffineTransformMakeScale(1.25, 1.25);
- }completion:^(BOOL finished) {
- [UIView animateWithDuration:0.5 animations:^{
- _focusView.transform = CGAffineTransformIdentity;
- } completion:^(BOOL finished) {
- _focusView.hidden = YES;
- }];
- }];
- }
- }
6、遇到的一些坑和解決辦法
1) 前后置攝像頭的切換
前后值不能切換,各種嘗試找了半天沒找到有原因。后來發(fā)現(xiàn)我在設(shè)置圖片尺寸的時(shí)候設(shè)置為1080P [self.session canSetSessionPreset: AVCaptureSessionPreset1920x1080] ,前置攝像頭并不支持這么大的尺寸,所以就不能切換前置攝像頭。我驗(yàn)證了下 前置攝像頭最高支持720P,720P以內(nèi)可自由切換。
當(dāng)然也可以在前后置攝像頭切換的時(shí)候,根據(jù)前后攝像頭來設(shè)置不同的尺寸,這里不在贅述。
2)焦點(diǎn)位置
CGPoint focusPoint = CGPointMake( point.y /size.height ,1-point.x/size.width );
setExposurePointOfInterest:focusPoint 函數(shù)后面Point取值范圍是取景框左上角(0,0)到取景框右下角(1,1)之間。官方是這么寫的:
The value of this property is a CGPoint that determines the receiver's focus point of interest, if it has one. A value of (0,0) indicates that the camera should focus on the top left corner of the image, while a value of (1,1) indicates that it should focus on the bottom right. The default value is (0.5,0.5).
我也試了按這個(gè)來但位置就是不對(duì),只能按上面的寫法才可以。前面是點(diǎn)擊位置的y/PreviewLayer的高度,后面是1-點(diǎn)擊位置的x/PreviewLayer的寬度
3)對(duì)焦和曝光
我在設(shè)置對(duì)焦是 先設(shè)置了模式setFocusMode,后設(shè)置對(duì)焦位置,就會(huì)導(dǎo)致很奇怪的現(xiàn)象,對(duì)焦位置是你上次點(diǎn)擊的位置。所以一定要先設(shè)置位置,再設(shè)置對(duì)焦模式。
曝光同上
7、寫在最后
附上demo:https://github.com/nanshanyi/photographDemo
常用到的基本就這么多,寫的并不完善,有什么不對(duì)的,歡迎大家批評(píng)指正,共同學(xué)習(xí)。