Thumbnail image of video - iphone

Question

I am selecting video clip from library. And i want to create thumbnail image of it. I have applied this code. But the image appeared rotated. I want its original view.
- (UIImage*)testGenerateThumbNailDataWithVideo {
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:appDelegate.videoURL options:nil];
AVAssetImageGenerator *generate = [[AVAssetImageGenerator alloc] initWithAsset:asset];
NSError *err = NULL;
CMTime time = CMTimeMake(1, 60);
CGImageRef imgRef = [generate copyCGImageAtTime:time actualTime:NULL error:&err];
[generate release];
NSLog(#"err==%#, imageRef==%#", err, imgRef);
UIImage *currentImg = [[[UIImage alloc] initWithCGImage:imgRef] autorelease];
static BOOL flag = YES;
if (flag) {
NSData *tmpData = UIImageJPEGRepresentation(currentImg, 0.8);
NSString *path = [NSString stringWithFormat:#"%#thumbNail.png", NSTemporaryDirectory()];
BOOL ret = [tmpData writeToFile:path atomically:YES];
NSLog(#"write to path=%#, flag=%d", path, ret);
flag = NO;
}
return currentImg;
}

Answer 1

Try using AVAssetImageGenerator instead. Apple discusses using AVAssetImageGenerator to create thumbnails here. Here is sample code, which grabs a single thumbnail image. You will need to include the AVFoundation framework. And also add CoreMedia framework
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:vidPath 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);
[gen release];
One more solution is
-(void)generateImage
{
AVURLAsset *asset=[[AVURLAsset alloc] initWithURL:self.url options:nil];
AVAssetImageGenerator *generator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
generator.appliesPreferredTrackTransform=TRUE;
[asset release];
CMTime thumbTime = CMTimeMakeWithSeconds(0,30);
AVAssetImageGeneratorCompletionHandler handler = ^(CMTime requestedTime, CGImageRef im, CMTime actualTime, AVAssetImageGeneratorResult result, NSError *error){
if (result != AVAssetImageGeneratorSucceeded) {
NSLog(#"couldn't generate thumbnail, error:%#", error);
}
[button setImage:[UIImage imageWithCGImage:im] forState:UIControlStateNormal];
thumbImg=[[UIImage imageWithCGImage:im] retain];
[generator release];
};
CGSize maxSize = CGSizeMake(320, 180);
generator.maximumSize = maxSize;
[generator generateCGImagesAsynchronouslyForTimes:[NSArray arrayWithObject:[NSValue valueWithCMTime:thumbTime]] completionHandler:handler];
}
Or
ALAsset
display image from URL retrieved from ALAsset in iPhone

Answer 2

Swift 5:
func previewImageForLocalVideo(at url: URL) -> UIImage? {
let asset = AVAsset(url: url)
let imageGenerator = AVAssetImageGenerator(asset: asset)
imageGenerator.appliesPreferredTrackTransform = true
var time = asset.duration
//If possible - take not the first frame (it could be completely black or white on camara's videos)
time.value = min(time.value, 2)
do {
let imageRef = try imageGenerator.copyCGImage(at: time, actualTime: nil)
return UIImage(cgImage: imageRef)
} catch let error as NSError {
print("Image generation failed with error \(error)")
return nil
}
}

Answer 3

This will solve the rotation issue
generate.appliesPreferredTrackTransform = YES