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在iOS中要拍照和录制视频最简单的方式就是调用UIImagePickerController，UIImagePickerController继承与UINavigationController，需要使用代理方法时需要同时遵守这两个协议，以前可能比较多的是使用UIImagePickerController来选择相册图片或者拍摄图片，其实它的功能还能用来拍摄视频。

使用UIImagePickerController拍照或者拍视频主要以下几个步骤：

创建一个全局的UIImagePickerController对象。

指定UIImagePickerController的来源sourceType，是来自UIImagePickerControllerSourceTypeCamera相机，还是来自UIImagePickerControllerSourceTypePhotoLibrary相册。

然后是设置mediaTypes媒体类型，这是录制视频必须设置的选项，默认情况下是kUTTypeImage（注意：mediaTypes的设置是在MobileCoreServices框架下），同还可以设置一些其他视频相关的属性，例如：videoQuality视频的质量、videoMaximumDuration视频的最大录制时长（默认为10s），cameraDevice摄像头的方向（默认为后置相机）。

指定相机的捕获模式cameraCaptureMode，设置mediaTypes后在设置捕获模式，注意的是捕获模式需要在相机来源sourceType为相机时设置，否则会出现crash。

适时的展示UIImagePickerController，然后在相应的代理方法保存和获取图片或视频。

下面还是上代码吧，更加清晰明了...

首先需要导入以下用到的几个头文件，同时遵守两个代理方法

#import"ViewController.h"#import#import#import@interfaceViewController(){UIImagePickerController*_imagePickerController;}

创建UIImagePickerController对象

- (void)viewDidLoad {    [superviewDidLoad];// Do any additional setup after loading the view, typically from a nib_imagePickerController = [[UIImagePickerControlleralloc] init];    _imagePickerController.delegate =self;    _imagePickerController.modalTransitionStyle =UIModalTransitionStyleFlipHorizontal;    _imagePickerController.allowsEditing =YES;

从摄像头获取图片或视频

#pragma mark 从摄像头获取图片或视频- (void)selectImageFromCamera{    _imagePickerController.sourceType =UIImagePickerControllerSourceTypeCamera;//录制视频时长，默认10s_imagePickerController.videoMaximumDuration =15;//相机类型（拍照、录像...）字符串需要做相应的类型转换_imagePickerController.mediaTypes = @[(NSString*)kUTTypeMovie,(NSString*)kUTTypeImage];//视频上传质量//UIImagePickerControllerQualityTypeHigh高清//UIImagePickerControllerQualityTypeMedium中等质量//UIImagePickerControllerQualityTypeLow低质量//UIImagePickerControllerQualityType640x480_imagePickerController.videoQuality =UIImagePickerControllerQualityTypeHigh;//设置摄像头模式（拍照，录制视频）为录像模式_imagePickerController.cameraCaptureMode =UIImagePickerControllerCameraCaptureModeVideo;    [selfpresentViewController:_imagePickerController animated:YEScompletion:nil];}

从相册获取图片或视频

#pragma mark 从相册获取图片或视频- (void)selectImageFromAlbum{//NSLog(@"相册");_imagePickerController.sourceType =UIImagePickerControllerSourceTypePhotoLibrary;        [selfpresentViewController:_imagePickerController animated:YEScompletion:nil];}

在imagePickerController:didFinishPickingMediaWithInfo:代理方法中处理得到的资源，保存本地并上传...

#pragma mark UIImagePickerControllerDelegate//该代理方法仅适用于只选取图片时- (void)imagePickerController:(UIImagePickerController*)picker didFinishPickingImage:(UIImage*)image editingInfo:(nullableNSDictionary *)editingInfo {NSLog(@"选择完毕----image:%@-----info:%@",image,editingInfo);}

//适用获取所有媒体资源，只需判断资源类型- (void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{NSString*mediaType=[info objectForKey:UIImagePickerControllerMediaType];//判断资源类型if([mediaType isEqualToString:(NSString*)kUTTypeImage]){//如果是图片self.imageView.image = info[UIImagePickerControllerEditedImage];//压缩图片NSData*fileData =UIImageJPEGRepresentation(self.imageView.image,1.0);//保存图片至相册UIImageWriteToSavedPhotosAlbum(self.imageView.image,self,@selector(image:didFinishSavingWithError:contextInfo:),NULL);//上传图片[selfuploadImageWithData:fileData];            }else{//如果是视频NSURL*url = info[UIImagePickerControllerMediaURL];//播放视频_moviePlayer.contentURL = url;        [_moviePlayer play];//保存视频至相册（异步线程）NSString*urlStr = [url path];dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0), ^{if(UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(urlStr)) {UISaveVideoAtPathToSavedPhotosAlbum(urlStr,self,@selector(video:didFinishSavingWithError:contextInfo:),nil);            }        });NSData*videoData = [NSDatadataWithContentsOfURL:url];//视频上传[selfuploadVideoWithData:videoData];    }    [selfdismissViewControllerAnimated:YEScompletion:nil];}

图片和视频保存完毕后的回调

#pragma mark 图片保存完毕的回调- (void) image: (UIImage*) image didFinishSavingWithError:(NSError*) error contextInfo: (void*)contextInf{    }#pragma mark 视频保存完毕的回调- (void)video:(NSString*)videoPath didFinishSavingWithError:(NSError*)error contextInfo:(void*)contextInf{if(error) {NSLog(@"保存视频过程中发生错误，错误信息:%@",error.localizedDescription);    }else{NSLog(@"视频保存成功.");    }}

以上仅是简单功能的实现，还有例如切换前后摄像头、闪光灯设置、对焦、曝光模式等更多功能...

作者：Shelin

链接：https://www.jianshu.com/p/e70a184d1f32

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