以mp4格式转换视频

Question

我是新手,并尝试创建一个记录视频或从库中选择视频的应用程序,而不是我将该视频上传到网络.但是这个文件不能在某些Android设备上播放.所以我想将其转换为mp4格式.

因此,我要问如何转换保存mov到mp4的objective-C？

仅供参考我已经研究了很多,但没有找到任何有用的信息.

这是我的代码:

- (void)openCamera {

    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    picker.delegate = self;
    picker.showsCameraControls = YES;
    picker.allowsEditing = YES;
    picker.mediaTypes = [[NSArray alloc] initWithObjects: (NSString *) kUTTypeMovie, nil];
    [self presentViewController:picker animated:YES completion:nil];
} 


- (void) imagePickerController: (UIImagePickerController *) picker didFinishPickingMediaWithInfo: (NSDictionary *) info {
    NSString *mediaType = [info objectForKey: UIImagePickerControllerMediaType];

    if (CFStringCompare ((__bridge_retained CFStringRef) mediaType, kUTTypeMovie, 0) == kCFCompareEqualTo)
    {
        NSString *moviePath = [[info objectForKey:UIImagePickerControllerMediaURL] path];
        videoURL = info[UIImagePickerControllerMediaURL];

        if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(moviePath))
        {
            UISaveVideoAtPathToSavedPhotosAlbum(moviePath, self, nil, nil);
        }
    }
    [self dismissViewControllerAnimated:YES completion:nil];
}

Answer 1

你可以查看我的帖子.它可能会帮助你

你正在做正确的事情..现在你需要将这个mov文件转换为mp4,如下所示.

NSString *mediaType = [info objectForKey: UIImagePickerControllerMediaType];
if (CFStringCompare ((__bridge_retained CFStringRef) mediaType, kUTTypeMovie, 0) == kCFCompareEqualTo)
 {
   if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(moviePath))
   {
         NSString *docDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
         NSString *moviePath = [[info objectForKey:UIImagePickerControllerMediaURL] path];
         NSString *videoPath1 =[NSString stringWithFormat:@"%@/xyz.mov",docDir];
         NSURL *videoURL = [info objectForKey:UIImagePickerControllerMediaURL];
         NSData *videoData = [NSData dataWithContentsOfURL:videoURL];
         [videoData writeToFile:videoPath1 atomically:NO];
       //  UISaveVideoAtPathToSavedPhotosAlbum(moviePath, self, nil, nil);
   }
 }

    AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:videoPath1] options:nil];
    NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset];

    if ([compatiblePresets containsObject:AVAssetExportPresetLowQuality])
    {
        AVAssetExportSession *exportSession = [[AVAssetExportSession alloc]initWithAsset:avAsset presetName:AVAssetExportPresetPassthrough];
        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        videoPath = [NSString stringWithFormat:@"%@/xyz.mp4", [paths objectAtIndex:0]];
        exportSession.outputURL = [NSURL fileURLWithPath:videoPath];
        NSLog(@"videopath of your mp4 file = %@",videoPath);  // PATH OF YOUR .mp4 FILE
        exportSession.outputFileType = AVFileTypeMPEG4;

      //  CMTime start = CMTimeMakeWithSeconds(1.0, 600);
      //  CMTime duration = CMTimeMakeWithSeconds(3.0, 600);           
      //  CMTimeRange range = CMTimeRangeMake(start, duration);            
      //   exportSession.timeRange = range;        
      //  UNCOMMENT ABOVE LINES FOR CROP VIDEO   
        [exportSession exportAsynchronouslyWithCompletionHandler:^{

            switch ([exportSession status]) {

                case AVAssetExportSessionStatusFailed:
                    NSLog(@"Export failed: %@", [[exportSession error] localizedDescription]);

                    break;

                case AVAssetExportSessionStatusCancelled:

                    NSLog(@"Export canceled");

                    break;

                default:

                    break;

            }
             UISaveVideoAtPathToSavedPhotosAlbum(videoPath, self, nil, nil);
            [exportSession release];

        }];

    }
[self dismissViewControllerAnimated:YES completion:nil];