首先添加AVFoundation和CoreMedia.framework

• 方法一

-(UIImage *)getImage:(NSString *)videoURL{

    AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:[NSURL fileURLWithPath:videoURL] options:nil];

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

    gen.appliesPreferredTrackTransform = YES;

    CMTime time = CMTimeMakeWithSeconds(0.0, 600);

    NSError *error = nil;

    CMTime actualTime;

    CGImageRef image = [gen copyCGImageAtTime:time actualTime:&actualTime error:&error];

    UIImage *thumb = [[UIImage alloc] initWithCGImage:image];

    CGImageRelease(image);

    return thumb;
}

• 方法二

MPMoviePlayerController *moviePlayer = [[MPMoviePlayerController alloc]initWithContentURL:videoURL]; 
moviePlayer.shouldAutoplay = NO; 
UIImage *thumbnail = [moviePlayer thumbnailImageAtTime:time timeOption:MPMovieTimeOptionNearestKeyFrame];

-(UIImage *)fFirstVideoFrame:(NSString *)path { 
    MPMoviePlayerController *mp = [[MPMoviePlayerController alloc] 
                               initWithContentURL:[NSURL fileURLWithPath:path]]; 
    UIImage *img = [mp thumbnailImageAtTime:0.0 
                             timeOption:MPMovieTimeOptionNearestKeyFrame]; 
    [mp stop]; 
    [mp release]; 
    return img; 
}

• 方法三

- (UIImage *)firstFrameWithVideoURL:(NSURL *)url size:(CGSize)size  
{  
    // 获取视频第一帧  
    NSDictionary *opts = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO] forKey:AVURLAssetPreferPreciseDurationAndTimingKey];  
    AVURLAsset *urlAsset = [AVURLAsset URLAssetWithURL:url options:opts];  
    AVAssetImageGenerator *generator = [AVAssetImageGenerator assetImageGeneratorWithAsset:urlAsset];  
    generator.appliesPreferredTrackTransform = YES;  
    generator.maximumSize = CGSizeMake(size.width, size.height);  
    NSError *error = nil;  
    CGImageRef img = [generator copyCGImageAtTime:CMTimeMake(0, 10) actualTime:NULL error:&error];  
    {  
        return [UIImage imageWithCGImage:img];  
    }  
    return nil;  
}