1.先看一下它包含的属性以及方法
UIImagePickerController属性 说明
@property(nonatomic) UIImagePickerControllerSourceType sourceType 拾取源类型，sourceType是枚举类型：
UIImagePickerControllerSourceTypePhotoLibrary：照片库，默认值
UIImagePickerControllerSourceTypeCamera：摄像头
UIImagePickerControllerSourceTypeSavedPhotosAlbum：相薄
@property(nonatomic,copy) NSArray *mediaTypes 媒体类型
kUTTypeImage (拍照,默认）
kUTTypeVideo（视频，但不带声音）
kUTTypeMovie（视频并带有声音）
@property(nonatomic) NSTimeInterval videoMaximumDuration 视频最大录制时长，默认为10 s
@property(nonatomic) UIImagePickerControllerQualityType videoQuality 视频质量，枚举类型：
UIImagePickerControllerQualityTypeHigh：高清质量
UIImagePickerControllerQualityTypeMedium：中等质量，适合WiFi传输
UIImagePickerControllerQualityTypeLow：低质量，适合蜂窝网传输
UIImagePickerControllerQualityType640x480：640*480
UIImagePickerControllerQualityTypeIFrame1280x720：1280*720
UIImagePickerControllerQualityTypeIFrame960x540：960*540
@property(nonatomic) BOOL showsCameraControls 是否显示摄像头控制面板，默认为YES
@property(nonatomic,retain) UIView *cameraOverlayView 摄像头上覆盖的视图，可用通过这个视频来自定义拍照或录像界面
@property(nonatomic) CGAffineTransform cameraViewTransform 摄像头形变
@property(nonatomic) UIImagePickerControllerCameraCaptureMode cameraCaptureMode 摄像头捕获模式，捕获模式是枚举类型：
UIImagePickerControllerCameraCaptureModePhoto：拍照模式
UIImagePickerControllerCameraCaptureModeVideo：视频录制模式
@property(nonatomic) UIImagePickerControllerCameraDevice cameraDevice 摄像头设备，cameraDevice是枚举类型：
UIImagePickerControllerCameraDeviceRear：前置摄像头
UIImagePickerControllerCameraDeviceFront：后置摄像头
@property(nonatomic) UIImagePickerControllerCameraFlashMode cameraFlashMode 闪光灯模式，枚举类型：
UIImagePickerControllerCameraFlashModeOff：关闭闪光灯
UIImagePickerControllerCameraFlashModeAuto：闪光灯自动
UIImagePickerControllerCameraFlashModeOn：打开闪光灯
UIImagePickerController类方法 说明
+ (BOOL)isSourceTypeAvailable:(UIImagePickerControllerSourceType)sourceType 指定的使用源类型是否可用，sourceType是枚举类型：
UIImagePickerControllerSourceTypePhotoLibrary：照片库
UIImagePickerControllerSourceTypeCamera：摄像头
UIImagePickerControllerSourceTypeSavedPhotosAlbum：相簿
+ (NSArray *)availableMediaTypesForSourceType:(UIImagePickerControllerSourceType)sourceType 指定的源设备上可用的媒体类型，一般就是图片和视频
+ (BOOL)isCameraDeviceAvailable:(UIImagePickerControllerCameraDevice)cameraDevice 指定的摄像头是否可用，cameraDevice是枚举类型：
UIImagePickerControllerCameraDeviceRear：前置摄像头
UIImagePickerControllerCameraDeviceFront：后置摄像头
+ (BOOL)isFlashAvailableForCameraDevice:(UIImagePickerControllerCameraDevice)cameraDevice 指定摄像头的闪光灯是否可用
+ (NSArray *)availableCaptureModesForCameraDevice:(UIImagePickerControllerCameraDevice)cameraDevice 获得指定摄像头上的可用捕获模式，捕获模式是枚举类型：
UIImagePickerControllerCameraCaptureModePhoto：拍照模式
UIImagePickerControllerCameraCaptureModeVideo：视频录制模式
UIImagePickerController对象方法说明
- (void)takePicture 编程方式拍照
- (BOOL)startVideoCapture 编程方式录制视频
- (void)stopVideoCapture 编程方式停止录制视频
UIImagePickerController代理方法说明
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info 媒体拾取完成
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker 取消拾取
UIImagePickerController扩展方法（主要用于保存照片、视频到相簿）说明
UIImageWriteToSavedPhotosAlbum(UIImage *image, id completionTarget, SEL completionSelector, void *contextInfo) 保存照片到相簿
UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(NSString *videoPath) 能否将视频保存到相簿
void UISaveVideoAtPathToSavedPhotosAlbum(NSString *videoPath, id completionTarget, SEL completionSelector, void *contextInfo) 保存视频到相簿
2.使用步骤
老规矩，首先添加框架AVFoundation、MobileCoreServices，引入头文件#import <AVFoundation/AVFoundation.h>，#import <MobileCoreServices/MobileCoreServices.h>记得这里需要遵循协议UIImagePickerControllerDelegate。
创建UIImagePickerController对象
UIImagePickerController *imagePicker=[[UIImagePickerController alloc]init];
imagePicker.delegate=self;//设置代理，检测操作
imagePicker.allowsEditing=YES／NO;//是否允许编辑
指定拾取源类型：拍照（相片库或者是相薄）；录视频（摄像头）
imagePicker.sourceType=UIImagePickerControllerSourceTypeCamera;//录视频
imagePicker.sourceType=UIImagePickerControllerSourceTypeSavedPhotosAlbum|UIImagePickerControllerSourceTypePhotoLibrary;//拍照
指定使用的摄像头（前置摄像头或是后置摄像头）
imagePicker.cameraDevice=UIImagePickerControllerCameraDeviceRear/UIImagePickerControllerCameraDeviceFront;
设置媒体类型：拍照：KUTTypeImage（默认）录制视频选择：kUTTypeVideo（视频，但不带声音）kUTTypeMovie（视频并带有声音）
imagePicker.mediaTypes=@[(NSString *)KUTTypeImage];//拍照
imagePicker.mediaTypes=@[(NSString *)kUTTypeVideo];//视频，但不带声音
imagePicker.mediaTypes=@[(NSString *)kUTTypeMovie];//视频并带有声音
设置捕获模式拍照／录制视频
imagePicker.cameraCaptureMode=UIImagePickerControllerCameraCaptureModeVideo;//设置摄像头模式（拍照，录制视频）
imagePicker.cameraCaptureMode=UIImagePickerControllerCameraCaptureModePhoto;//拍照
其它设置可根据上面的属性按需要设置，接下来需要实现几个回调函数
//拍照或录制视频结束后调用
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
NSString *mediaType=[info objectForKey:UIImagePickerControllerMediaType];//用于判断媒体类型
if ([mediaType isEqualToString:(NSString *)kUTTypeImage]) {//如果是拍照
UIImage *image;
//如果允许编辑则获得编辑后的照片，否则获取原始照片
if (imagePicker.allowsEditing) {
image=[info objectForKey:UIImagePickerControllerEditedImage];//获取编辑后的照片
}else{
image=[info objectForKey:UIImagePickerControllerOriginalImage];//获取原始照片
}
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);//保存图片到相簿
}else if([mediaType isEqualToString:(NSString *)kUTTypeMovie]){//如果是录制视频
NSURL *url=[info objectForKey:UIImagePickerControllerMediaURL];//视频路径
NSString *strUrl=[url path];
if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(strUrl)) {
UISaveVideoAtPathToSavedPhotosAlbum(urlStr, self, @selector(video:didFinishSavingWithError:contextInfo:), nil);//保存视频到相簿
}
}
}
//视频保存后的回调
- (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{
error判断成功与否，做自己想要的操作
}