How to allow Zoom-Out until an image fills a Webview and doesn't exceeed its boundaries?

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http://stackoverflow.com – I'm using a common approach to display an image in Full-screen and support zooming by a WebView and enablling zoom controls in it, my problem is when the Image width is larger than the Screen width e.g. on Galaxy S2 screen (480px width) if I display a 600px by 600px image in a web view, the max Zoom-out still crops the image and displays a horizontal scroll, and there's no way to zoom-out (i.e. less than 100%). Is there a solution for this to enable the zoom to go to levels such as 50% or if there's a better approach than using the WebView and still support zoom ? (HowTos)