Android webview pinch zoom Problem

Hi guyz im able to pinch zoom the image in webview its working properly. Zoom in is working fine but problem is zoom out. Image goes small and small. Ho开发者_高级运维w can i limit zoom out to the size of the image?

    mWebView.getSettings().setSupportZoom(true);  
    mWebView.getSettings().setBuiltInZoomControls(true);