iOS upload video to server using AFN sample code

//Convert video to MP4//Transcoding operation..._hud.mode = MBProgressHUDModeIndeterminate;
_hud.labelText = @"Transcoding...";
AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:_filePathURL options:nil];
NSDateFormatter* formater = [[NSDateFormatter alloc] init];
[formater setDateFormat:@"yyyyMMddHHmmss"];
_fileName = [NSString stringWithFormat:@"output-%@.mp4",[formater stringFromDate:[NSDate date]]];
_outfilePath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/%@", _fileName];
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset];

if ([compatiblePresets containsObject:AVAssetExportPresetMediumQuality]) {
  MyLog(@"outPath = %@",_outfilePath);
  AVAssetExportSession *exportSession = [[AVAssetExportSession alloc]initWithAsset:avAsset presetName:AVAssetExportPresetMediumQuality];
   = [NSURL fileURLWithPath:_outfilePath];
   = AVFileTypeMPEG4;
  [exportSession exportAsynchronouslyWithCompletionHandler:^{
    if ([exportSession status] == AVAssetExportSessionStatusCompleted) {
      MyLog(@"AVAssetExportSessionStatusCompleted---Conversion was successful");
      _filePath = _outfilePath;
      _filePathURL = [NSURL URLWithString:[NSString stringWithFormat:@"file://%@",_outfilePath]];
       MyLog(@"Conversion is complete_filePath = %@\\n_filePathURL = %@",_filePath,_filePathURL);
      //Get size and length      [self SetViewText];
      [self uploadNetWorkWithParam:@{@"contenttype":@"application/octet-stream",@"discription":description}];
    }else{
      MyLog(@"The conversion failed, the value is: %li, possible reason: %@",(long)[exportSession status],[[exportSession error] localizedDescription]);
      [_hud hide:YES];
      [MyHelper showAlertWith:nil txt:@"Conversion failed, please try again"];
    }
  }];
}

- (void)uploadNetWorkWithParam:(NSDictionary*)dict {
  MyLog(@"Start uploading_filePath = %@\\n_filePathURL = %@",_filePath,_filePathURL);
  AFHTTPRequestSerializer *ser=[[AFHTTPRequestSerializer alloc]init];
  NSMutableURLRequest *request =
  [ser multipartFormRequestWithMethod:@"POST"
               URLString:[NSString stringWithFormat:@"%@%@",kBaseUrl,kVideoUploadUrl]
               parameters:@{@"path":@"show",@"key":_key,@"discription":dict[@"discription"],@"isimage":@(_isImage)}
       constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
           [formData appendPartWithFileURL:_filePathURL name:@"file" fileName:_fileName mimeType:dict[@"contenttype"] error:nil];
         if (!_isImage) {
    [formData appendPartWithFileURL:_path2Url name:@"tmp" fileName:@"" mimeType:@"image/png" error:nil];
         }
       } error:nil];
  //@"image/png"  @"application/octet-stream" mimeType
  AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
  NSProgress *progress = nil;
  NSURLSessionUploadTask *uploadTask = [manager uploadTaskWithStreamedRequest:request progress:&progress completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
       MyLog(@"request = %@", request );
       MyLog(@"response = %@", response );
      MyLog(@"Error: %@", error );
      [_hud hide:YES];
      CXAlertView *alert=[[CXAlertView alloc]initWithTitle:NSLocalizedString(@"Warning", nil)
                             message:NSLocalizedString(@"Upload Failed",nil)
                        cancelButtonTitle:NSLocalizedString(@"Iknow", nil)];
       = NO;
      [alert show];
    } else {
      MyLog(@"%@ %@", response, responseObject);
      NSDictionary *backDict=(NSDictionary *)responseObject;
      if ([backDict[@"success"] boolValue] != NO) {
        _hud.labelText = NSLocalizedString(@"Updating", nil);
        [self UpdateResxDateWithDict:backDict discription:dict[@"discription"]];
        [_hud hide:YES];
      }else{
        [_hud hide:YES];
        [MyHelper showAlertWith:nil txt:backDict[@"msg"]];
      }
    }
    [progress removeObserver:self
           forKeyPath:@"fractionCompleted"
             context:NULL];
  }];
  [progress addObserver:self
        forKeyPath:@"fractionCompleted"
         options:NSKeyValueObservingOptionNew
         context:NULL];
  [progress setUserInfoObject:@"someThing" forKey:@"."];
  [uploadTask resume];
}

-(void)ClearMovieFromDoucments{
  NSFileManager *fileManager = [NSFileManager defaultManager];
  NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
  NSString *documentsDirectory = [paths objectAtIndex:0];
  NSArray *contents = [fileManager contentsOfDirectoryAtPath:documentsDirectory error:NULL];
  NSEnumerator *e = [contents objectEnumerator];
  NSString *filename;
  while ((filename = [e nextObject])) {
    MyLog(@"%@",filename);
    if ([filename isEqualToString:@""]) {
      MyLog(@"delete%@",filename);
      [fileManager removeItemAtPath:[documentsDirectory stringByAppendingPathComponent:filename] error:NULL];
      continue;
    }
    if ([[[filename pathExtension] lowercaseString] isEqualToString:@"mp4"]||
      [[[filename pathExtension] lowercaseString] isEqualToString:@"mov"]||
      [[[filename pathExtension] lowercaseString] isEqualToString:@"png"]) {
      MyLog(@"delete%@",filename);
      [fileManager removeItemAtPath:[documentsDirectory stringByAppendingPathComponent:filename] error:NULL];
    }
  }
}