iOS从相册选择视频和保存视频到相册

最近，在做有关视频操作的功能。需要从相册选择视频，处理之后再保存到相册。

选择视频：

方式一：用系统的UIImagePickerController

贴代码：

- (void)selectAction{        NSLog(@"从相册选择");    UIImagePickerController *picker=[[UIImagePickerController alloc] init];    picker.delegate=self;    picker.allowsEditing=NO;    picker.videoMaximumDuration = 1.0;//视频最长长度    picker.videoQuality = UIImagePickerControllerQualityTypeMedium;//视频质量    //媒体类型：@"public.movie" 为视频  @"public.image" 为图片    //这里只选择展示视频    picker.mediaTypes = [NSArray arrayWithObjects:@"public.movie", nil];        picker.sourceType= UIImagePickerControllerSourceTypeSavedPhotosAlbum;        [kCurNavController presentViewController:picker animated:YES completion:^{        }];}#pragma mark UIImagePickerControllerDelegate- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{        NSString *mediaType=[info objectForKey:UIImagePickerControllerMediaType];        if ([mediaType isEqualToString:@"public.movie"]){        //如果是视频        NSURL *url = info[UIImagePickerControllerMediaURL];//获得视频的URL        NSLog(@"url %@",url);        self.videoUrl = url;    }        [self dismissViewControllerAnimated:YES completion:nil];}

选择视频:

方式二：利用三方库TZImagePickerController 

贴代码：

-  (void)selectThreeKuAction{        TZImagePickerController *imagePickerVc = [[TZImagePickerController alloc] initWithMaxImagesCount:1 columnNumber:4 delegate:nil pushPhotoPickerVc:YES];        //展示相册中的视频    imagePickerVc.allowPickingVideo = YES;    //不展示图片    imagePickerVc.allowPickingImage = NO;    //不显示原图选项    imagePickerVc.allowPickingOriginalPhoto = NO;    //按时间排序    imagePickerVc.sortAscendingByModificationDate = YES;        //选择完视频之后的回调    [imagePickerVc setDidFinishPickingVideoHandle:^(UIImage *coverImage,id asset){                //iOS8以后返回PHAsset        PHAsset *phAsset = asset;                if (phAsset.mediaType == PHAssetMediaTypeVideo) {            //从PHAsset获取相册中视频的url            PHVideoRequestOptions *options = [[PHVideoRequestOptions alloc] init];            options.version = PHImageRequestOptionsVersionCurrent;            options.deliveryMode = PHVideoRequestOptionsDeliveryModeAutomatic;            PHImageManager *manager = [PHImageManager defaultManager];            [manager requestAVAssetForVideo:phAsset options:options resultHandler:^(AVAsset * _Nullable asset, AVAudioMix * _Nullable audioMix, NSDictionary * _Nullable info) {                AVURLAsset *urlAsset = (AVURLAsset *)asset;                                NSURL *url = urlAsset.URL;                self.videoUrl = url;                NSLog(@"%@",url);            }];        }    }];    [kCurNavController presentViewController:imagePickerVc animated:YES completion:nil];}

以上都得到了视频的URL，之后再操作就方便了。

裁剪视频：

//视频裁剪- (void)cropWithVideoUrlStr:(NSURL *)videoUrl start:(CGFloat)startTime end:(CGFloat)endTime completion:(void (^)(NSURL *outputURL, Float64 videoDuration, BOOL isSuccess))completionHandle{    AVURLAsset *asset =[[AVURLAsset alloc] initWithURL:videoUrl options:nil];        //获取视频总时长    Float64 duration = CMTimeGetSeconds(asset.duration);        NSString *outputPath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"dafei.mp4"];    NSURL *outputURL = [NSURL fileURLWithPath:outputPath];    //如果文件已经存在，先移除，否则会报无法存储的错误    NSFileManager *manager = [NSFileManager defaultManager];    [manager removeItemAtPath:outputPath error:nil];        NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:asset];    if ([compatiblePresets containsObject:AVAssetExportPresetMediumQuality])    {                AVAssetExportSession *exportSession = [[AVAssetExportSession alloc]                                               initWithAsset:asset presetName:AVAssetExportPresetPassthrough];            exportSession.outputURL =  outputURL;        //视频文件的类型        exportSession.outputFileType = AVFileTypeQuickTimeMovie;        //输出文件是否网络优化        exportSession.shouldOptimizeForNetworkUse = YES;                //要截取的开始时间        CMTime start = CMTimeMakeWithSeconds(startTime, asset.duration.timescale);        //要截取的总时长        CMTime duration = CMTimeMakeWithSeconds(endTime - startTime,asset.duration.timescale);        CMTimeRange range = CMTimeRangeMake(start, duration);        exportSession.timeRange = range;                [exportSession exportAsynchronouslyWithCompletionHandler:^{            switch ([exportSession status]) {                case AVAssetExportSessionStatusFailed:                {                    NSLog(@"合成失败：%@", [[exportSession error] description]);                    completionHandle(outputURL, endTime, NO);                }                    break;                case AVAssetExportSessionStatusCancelled:                {                    completionHandle(outputURL, endTime, NO);                }                    break;                case AVAssetExportSessionStatusCompleted:                {                    //成功                    completionHandle(outputURL, endTime, YES);                                    }                    break;                default:                {                    completionHandle(outputURL, endTime, NO);                } break;            }        }];    }}

处理完视频之后，把视频保存到相册：

方式一：

//保存视频到相册- (void)writeVideoToPhotoLibrary:(NSURL *)url{    ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];        [library writeVideoAtPathToSavedPhotosAlbum:url completionBlock:^(NSURL *assetURL, NSError *error){        if (error == nil) {                        UIAlertController * alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"视频保存成功" preferredStyle:UIAlertControllerStyleAlert];                        [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {                            }]];            [self presentViewController:alert animated:true completion:nil];                    }else{            UIAlertController * alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"视频保存失败" preferredStyle:UIAlertControllerStyleAlert];                        [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {                            }]];            [self presentViewController:alert animated:true completion:nil];        }    }];}

保存视频到相册，方式二：用下面这个方法

UISaveVideoAtPathToSavedPhotosAlbum(path, self, @selector(video:didFinishSavingWithError:contextInfo:), nil);

// 视频保存回调- (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo: (void *)contextInfo {        if (error == nil) {                UIAlertController * alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"视频保存成功" preferredStyle:UIAlertControllerStyleAlert];                [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {                    }]];        [self presentViewController:alert animated:true completion:nil];            }else{        UIAlertController * alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"视频保存失败" preferredStyle:UIAlertControllerStyleAlert];                [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {                    }]];       [self presentViewController:alert animated:true completion:nil];    }}