resizing image with appropriate aspect ratio - iphone

Question

I am working on new app, in which , i have different sizes of images. I have tried many times with different solution but could not find out the proper aspect ratio for images. I want to display images with a high quality too. There is some images have resolution 20*20 to 3456 * 4608 or it may be so high.
All images will be display without cropping ,but our app screen size is 300 * 370 pxls.
I was follow the following references :
1: Resize UIImage with aspect ratio?
2: UIViewContentModeScaleAspectFit
3: scale Image in an UIButton to AspectFit?
4:Resize UIImage with aspect ratio?

Answer 1

The code that I use for resizing images to an edge 1000px at most is this :
const int maxPhotoWidthOrHeight = 1000;
- (UIImage*)resizeImageWithImage:(UIImage*)image
{
CGFloat oldWidth = image.size.width;
CGFloat oldHeight = image.size.height;
NSLog(#"Old width %f , Old Height : %f ",oldWidth,oldHeight);
if (oldHeight > maxPhotoWidthOrHeight || oldWidth > maxPhotoWidthOrHeight) {//resize if necessary
CGFloat newHeight;
CGFloat newWidth;
if (oldHeight > oldWidth ) {
newHeight = maxPhotoWidthOrHeight;
newWidth = oldWidth * (newHeight/oldHeight);
}
else{
newWidth = maxPhotoWidthOrHeight;
newHeight = oldHeight * (newWidth/oldWidth);
}
CGSize newSize = CGSizeMake(newWidth, newHeight);
UIGraphicsBeginImageContext( newSize );
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSLog(#"New width %f , New Height : %f ",newImage.size.width,newImage.size.height);
return newImage;
}
else{//do not resize because both edges are less than 1000px
return image;
}
}

Answer 2

-- Please add you code example, otherwise its difficult to give any solution to your problem.
A solution found here is also How to scale a UIImageView proportionally?
imageView.contentMode = UIViewContentModeScaleAspectFit;