iOS 视频选择压缩

 

 

//原理,还是调用UIImagePickerController控制器,设置Type为视频

 

#import "ViewController.h"

#import <AVFoundation/AVFoundation.h>

 

@interface ViewController ()<UIImagePickerControllerDelegate,UINavigationControllerDelegate>

 

@end

 

@implementation ViewController

 

- (void)viewDidLoad {

    [super viewDidLoad];

}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

    //打开控制器

    UIImagePickerController *picker=[[UIImagePickerController alloc]init];

    //picker.sourceType=UIImagePickerControllerSourceTypeCamera;//设置摄像头类型 摄像头

    //picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;//打开相册,获取资源,视频和图片用户拍摄的照片可以删除,

    //picker.sourceType=UIImagePickerControllerSourceTypePhotoLibrary;//打开相册库,用户与电脑同步的,不能删除

    picker.delegate=self;

    //设置媒体类型

    picker.mediaTypes=[UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypePhotoLibrary];

    //显示控制器

    [self presentViewController:picker animated:YES completion:nil];

    

    

}

#pragma mark UIImagePickerControllerDelegate

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

{

    //如果是视频返回的是URL

    NSURL*url=info[UIImagePickerControllerMediaURL];

    //使用媒体工具 压缩

    [self compressVideo:url];

    //关闭控制器

    [self dismissViewControllerAnimated:YES completion:nil];

}

//压缩

-(void)compressVideo:(NSURL*)url

{

    //使用媒体工具(AVFoundation框架下的)

    //Asset 资源 可以是图片音频视频

    AVAsset *asset=[AVAsset assetWithURL:url];

    //设置压缩的格式

    AVAssetExportSession *session=[AVAssetExportSession exportSessionWithAsset:asset presetName:AVAssetExportPresetMediumQuality];//mediumquality:中等质量

    //设置导出路径

    NSString *path=[NSTemporaryDirectory() stringByAppendingPathComponent:@"needAV.mov"];

    //创建文件管理类 导出失败,删除已经导出的

    NSFileManager *manager=[[NSFileManager alloc]init];

    //删除已经存在的

    [manager removeItemAtPath:path error:NULL];

    //设置到处路径

    session.outputURL=[NSURL fileURLWithPath:path];

    //设置输出文件的类型

    session.outputFileType=AVFileTypeQuickTimeMovie;

    //开辟子线程处理耗时操作

    [session exportAsynchronouslyWithCompletionHandler:^{

        NSLog(@"导出完成!路径:%@",path);

    }];

    

    

}

 

 

 

 

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

}

 

@end

 

 

 

//参考资料 http://www.cnblogs.com/wanghuaijun/p/5575255.html。