UIImagepickercontroller:转换为低质量视频错误

Question

我正在[info objectForKey:UIImagePickerControllerMediaURL]从UIImagepickercontroller的didFinishPickingMediaWithInfo方法获得输入.

NSURL *inputURL = [NSURL URLWithString:inputurlstring];

我从这段代码中给出了outputurl

        NSString  *documentsDirectory = [paths objectAtIndex:0];
        NSString *videoPath = [NSString stringWithFormat:@"%@/%@", documentsDirectory,@"capturedvideo.MOV"];
        NSURL *outputURL = [NSURL fileURLWithPath:videoPath];

我使用以下代码来获得低质量的视频

 - (void)convertVideoToLowQuailtyWithInputURL:(NSURL*)inputURL 
    outputURL:(NSURL*)outputURL 
    handler:(void (^)(AVAssetExportSession*))handler 
    { 

    [[NSFileManager defaultManager] removeItemAtURL:outputURL error:nil]; 
    AVURLAsset *asset = [AVURLAsset URLAssetWithURL:inputURL options:nil]; 
    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:asset presetName:AVAssetExportPresetLowQuality]; 
    exportSession.outputURL = outputURL; 
    exportSession.outputFileType = AVFileTypeQuickTimeMovie; 

    [exportSession exportAsynchronouslyWithCompletionHandler:^(void) 
    { 
    if (exportSession.status == AVAssetExportSessionStatusCompleted) 
    { 
    printf("completed\n"); 

    } 
    else 
    { 
    printf("error\n"); 
    NSLog(@"error is %@",exportSession.error); 

    } 

    }]; 
}           

我只使用大文件时出现以下错误.因为当我使用小尺寸视频文件时,我没有收到任何错误.

Error Domain=NSURLErrorDomain Code=-1 "unknown error" UserInfo=0x616d890         
 {NSErrorFailingURLStringKey=/private/var/mobile/Applications/EE1E6701-EED0-4830-BD1D-7366680713C0/tmp//trim.7mL7VS.MOV, NSErrorFailingURLKey=/private/var/mobile/Applications/EE1E6701-EED0-4830-BD1D-7366680713C0/tmp//trim.7mL7VS.MOV, NSLocalizedDescription=unknown error, NSUnderlyingError=0x2d1460 "The operation couldn’t be completed. (OSStatus error -12935.)", NSURL=/private/var/mobile/Applications/EE1E6701-EED0-4830-BD1D-7366680713C0/tmp//trim.7mL7VS.MOV}

Answer 1

上面的代码完美运行。唯一的变化是 inputURL。

将 inputURL 更改为 fileURLWithPath 后：

 NSURL *inputURL = [NSURL fileURLWithPath:inputurlstring];

现在它完美地工作了。