I am very new to ImgScalr API.I need to resize my images to different views, one of them being a mobile view and second a thumbnail view. I have made use of the resize method, but have a doubt. Which is the best of the resize method to resizing the image out of the multiple options available that keeps the proper aspect ratio(as in the image doesnt become blurred)
One thing I noticed was that every resize method takes in a targetSize argument. How does specifiying this field make sure that the aspect ratio of the image does not get affected.
What should the ideal arguments to the resize method be, given that I need to generate a 2 KB thumbnail view of my input image that may be of size of around 2 MB.
I am a bit confused because of the lack of enough documentation and examples.
imgscalr author here - definitely understand the confusion, the code base itself (if you happen to glance at GitHub) is almost 50% comments if you are curious how the library works, but from a usage perspective you are right - I didn't put a lot of time into examples.
Hopefully I can hit some highlights quickly for you...
Aspect Ratios
A core design tenant of imgscalr is to always honor the aspect ratio - so if you pass in 200x1 (some ridiculous dimension as an example) it will attempt to calculate the minimum dimension that will meet those 'target' dimensions.
This is handy if you always want your thumbnails in a certain box, like 200x200 -- just pass that in and imgscalr will determine a final width/height that won't be bigger than that (possibly something like 200x127 or 78x200)
Quality
By default the library does what is called a 'balanced' approach to quality by considering the delta in dimension change as well as scaling up/scaling down and chooses the most approach approach (speed VS quality).
You can force it to always scale as quickly as possible (good idea for scaling up operations) or can force it to always use high or ultra quality (good idea if you want really crisp thumbnails or other operations that drastically reduce the image resolution and you want them to still look decent)
On top of that you can also ask the library to apply some additional filtering to the image (called Image Ops) -- I ship some handy defaults out of the box like the anti-aliasing one if you are getting jagged edges on a lot of source material you are scaling (common when scaling screenshots of desktops and other things with diag straight lines)
Overall
The library is meant to be as simple as possible to use, something no harder than:
BufferedImage thumbnail = Scalr.resize(src, 128);
will get you started... all the other operations around quality, fitting, modes, ops, etc. are just additional things you can chose to do if you decide the result isn't quite what you wanted.
Hope that helps!