写个分类:
// UIImage+WBFirstImage.h
+ (UIImage*) thumbnailImageForVideo:(NSURL *)videoURL atTime:(NSTimeInterval)time;
// UIImage+WBFirstImage.m
#import <AVFoundation/AVFoundation.h>
#import <CoreMedia/CoreMedia.h>
#import <Foundation/NSObject.h>
#import <Foundation/NSNotification.h>
+ (UIImage*) thumbnailImageForVideo:(NSURL *)videoURL atTime:(NSTimeInterval)time {
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];
NSParameterAssert(asset);
AVAssetImageGenerator *assetImageGenerator =[[AVAssetImageGenerator alloc] initWithAsset:asset];
assetImageGenerator.appliesPreferredTrackTransform = YES;
assetImageGenerator.apertureMode = AVAssetImageGeneratorApertureModeEncodedPixels;
CGImageRef thumbnailImageRef = NULL;
CFTimeInterval thumbnailImageTime = time;
NSError *thumbnailImageGenerationError = nil;
thumbnailImageRef = [assetImageGenerator copyCGImageAtTime:CMTimeMake(thumbnailImageTime, 10)actualTime:NULL error:&thumbnailImageGenerationError];
if(!thumbnailImageRef)
NSLog(@"thumbnailImageGenerationError %@",thumbnailImageGenerationError);
UIImage*thumbnailImage = thumbnailImageRef ? [[UIImage alloc]initWithCGImage: thumbnailImageRef] : nil;
return thumbnailImage;
}
调用
UIImage *firstImage = [UIImage thumbnailImageForVideo:[NSURL URLWithString:_statusModel.videoUrl] atTime:10];
如果我们想在这张图片上加个占位图却不想再创建一个imageView呢?
- (UIImage *)addImage:(UIImage *)image1 toImage:(UIImage *)image2 {
UIGraphicsBeginImageContext(image1.size);
UIGraphicsBeginImageContext(image2.size);
[image2 drawInRect:CGRectMake(0, 0, image2.size.width, image2.size.height)];
[image1 drawInRect:CGRectMake(image2.size.width/2-70, image2.size.height/2-70, 140, 140)];
UIImage *resultImage=UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resultImage;
}
调用
UIImage *addImage = [self addImage:[UIImage imageNamed:@"play"] toImage:firstImage];
