Grabbing First Frame of a Video - Thumbnail Resolution - iPhone

问题

I want to display the (static) first frame of a video in my app as a preview.

I have read through this thread and understand that I could use a thumbnail :

Getting a thumbnail from a video url or data in iPhone SDK

I have two questions :

1) What is the resolution of the thumbnail ? I am looking to make the preview a 4:3 format and wonder if the image will end up looking blurry if enlarged.

2) Does the resolution of the thumbnail differ for iPhone / iPad ?

3) Is there a better way to grab and display the first frame of a video ?

Thank you.

回答1:

Following code may helping to you

NSString *str = [[self.vedioArray objectAtIndex:i] valueForKey:@"vName"];
    NSURL *videoURL = [NSURL URLWithString:str] ;
    MPMoviePlayerController *player = [[[MPMoviePlayerController alloc] initWithContentURL:videoURL]autorelease];
  UIImage  *thumbnail = [player thumbnailImageAtTime:1.0 timeOption:MPMovieTimeOptionNearestKeyFrame];
    player = nil;

来源：https://stackoverflow.com/questions/10209012/grabbing-first-frame-of-a-video-thumbnail-resolution-iphone