根据视频地址获取某一帧的图像

http://blog.fuckbugs.me/category/ios/

 

//CatchImage.h

 

#import <Foundation/Foundation.h>

 

@interface CatchImage : NSObject

 

/*

 *videoURL:视频地址(本地/网络)

 *time      :第N帧

 */

+ (UIImage*) thumbnailImageForVideo:(NSURL *)videoURL atTime:(NSTimeInterval)time;

@end

 

//CatchImage.m

 

#import "CatchImage.h"

#import <AVFoundation/AVFoundation.h>

#import <AVFoundation/AVAssetImageGenerator.h>

#import <AVFoundation/AVAsset.h>

 

@implementation CatchImage

 

+ (UIImage*) thumbnailImageForVideo:(NSURL *)videoURL atTime:(NSTimeInterval)time {

    

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

    NSParameterAssert(asset);

    AVAssetImageGenerator *assetImageGenerator =[[[AVAssetImageGenerator alloc] initWithAsset:asset]autorelease];

    assetImageGenerator.appliesPreferredTrackTransform = YES;

    assetImageGenerator.apertureMode =AVAssetImageGeneratorApertureModeEncodedPixels;

    

    CGImageRef thumbnailImageRef = NULL;

    CFTimeInterval thumbnailImageTime = time;

    NSError *thumbnailImageGenerationError = nil;

    thumbnailImageRef = [assetImageGenerator copyCGImageAtTime:CMTimeMake(thumbnailImageTime, 60)actualTime:NULL error:&thumbnailImageGenerationError];

    

    if(!thumbnailImageRef)

        NSLog(@"thumbnailImageGenerationError %@",thumbnailImageGenerationError);

    

    UIImage*thumbnailImage = thumbnailImageRef ? [[[UIImage alloc]initWithCGImage:thumbnailImageRef] autorelease] : nil;

    

    return thumbnailImage;

}

@end