我想从视频中获取每一帧的缩略图,然后将这些图像保存在可变图像数组中。
我想用这个图像作为动画播放。
NSURL* assetURL = [self.asset valueForProperty:ALAssetPropertyAssetURL];
NSDictionary* assetOptions = nil;
AVAsset* myAsset = [[AVURLAsset alloc] initWithURL:assetURL options:assetOptions];
self.imageGenerator = [AVAssetImageGenerator assetImageGeneratorWithAsset:myAsset];
int duration = CMTimeGetSeconds([myAsset duration]);
for(int i = 0; i<duration; i++)
{
CGImageRef imgRef = [self.imageGenerator copyCGImageAtTime:CMTimeMake(i, duration) actualTime:NULL error:nil];
UIImage* thumbnail = [[UIImage alloc] initWithCGImage:imgRef scale:UIViewContentModeScaleAspectFit orientation:UIImageOrientationUp];
[thumbnailImages addObject:thumbnail];
}
我正在使用上面的代码来获取缩略图,但问题是如果有一个 2 秒的视频,我只得到 2 个缩略图,但我想要 20 个缩略图(每秒 10 个缩略图)。
那么,如何使用CMTimeMake每0.1秒获取缩略图
最佳答案
代码形式引用站点:Thumbnail image from Video
目标 - C
-(UIImage *)generateThumbImage : (NSString *)filepath
{
NSURL *url = [NSURL fileURLWithPath:filepath];
AVAsset *asset = [AVAsset assetWithURL:url];
AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc]initWithAsset:asset];
self.imageGenerator.appliesPreferredTrackTransform = YES;
CMTime time = [asset duration];
time.value = 0;
Float duration = CMTimeGetSeconds([myAsset duration]);
for(Float i = 0.0; i<duration; i=i+0.1)
{
CGImageRef imgRef = [self.imageGenerator copyCGImageAtTime:CMTimeMake(i, duration) actualTime:NULL error:nil];
UIImage* thumbnail = [[UIImage alloc] initWithCGImage:imgRef scale:UIViewContentModeScaleAspectFit orientation:UIImageOrientationUp];
[thumbnailImages addObject:thumbnail];
}
}
swift
func generateThumbImage(url : NSURL) -> UIImage{
var asset : AVAsset = AVAsset.assetWithURL(url) as! AVAsset
var assetImgGenerate : AVAssetImageGenerator = AVAssetImageGenerator(asset: asset)
assetImgGenerate.appliesPreferredTrackTransform = true
var error : NSError? = nil
var time : CMTime = CMTimeMake(1, 30)
var img : CGImageRef = assetImgGenerate.copyCGImageAtTime(time, actualTime: nil, error: &error)
var frameImg : UIImage = UIImage(CGImage: img)!
return frameImg
}
关于ios - 如何从 iOS 中的 ALAsset 获取视频的缩略图?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/31262606/