//  本地图库按钮监听

-(void)pictureClicked{

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

    pickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

    pickerController.mediaTypes =@[(NSString*)kUTTypeMovie];

    pickerController.allowsEditing=YES;

    pickerController.delegate=self;

    [self.navigationController presentViewController:pickerController animated:YES completion:nil];

}

-(void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionaryid> *)info{

    [pickerdismissViewControllerAnimated:YES completion:nil];

//这个是获取本地图库视频的路径

    NSURL *URL = info[UIImagePickerControllerMediaURL];

    NSString*URLStr = [NSStringstringWithFormat:@"%@",URL];

    //获取本地视频的第一帧当作封面

    AVURLAsset*asset = [[AVURLAssetalloc]initWithURL:URLoptions:nil];

    AVAssetImageGenerator *assetGen = [[AVAssetImageGenerator alloc] initWithAsset:asset];

    assetGen.appliesPreferredTrackTransform = YES;

    CMTime time = CMTimeMakeWithSeconds(0.0, 600);

    NSError*error =nil;

    CMTimeactualTime;

    CGImageRefimage = [assetGencopyCGImageAtTime:timeactualTime:&actualTimeerror:&error];

//这个就是第一帧的图片了

    UIImage*videoImage = [[UIImagealloc]initWithCGImage:image];

    //  获取本地视频的时长

    NSDictionary *opts = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO]

                                                     forKey:AVURLAssetPreferPreciseDurationAndTimingKey];

    AVURLAsset*urlAsset = [AVURLAssetURLAssetWithURL:URLoptions:opts];

    floatsecond = urlAsset.duration.value/ urlAsset.duration.timescale;

    if(second >60){

        SHOW_ALERT(@"视频长度不能大于一分钟");

    }else{

SHOW_ALERT(@"这里写业务逻辑");

    }

}