This is in continuation of my posts on Seam Carving. In the previous article, I was talking about making Seam Carving as a web service. I had noted that both HTML Canvas, and Flash were terribly slow while resizing images. The Java implementation of the algorithm seemed fast enough, and given network speeds of today, server based image resizing seems like a practical solution to bring seam carving to the browser. Due to lack of hosting space, I was not really able to host the servlet. However, it would be great if someone could host the Java Servlet that I wrote.
The corresponding client side operations would now become a lot simpler. The HTML Pages that contains images that require to be contextually resized could have a class, say something like <img src="http://www.blogger.com/../img.jpg" class="seam-resize" />. A non-obtrusive JavaScript on the page could have a hook to all the resize events of the image, and replace the source of the image with something that is like
http://../imageResizeServlet?url=originalUrl.jpg&width=newWidth&height=newHeightThe Servlet internally reads the original image in an InputStream and applies the seam carve function on it. The output of the servlet is the image with the appropriate headers. As an optimization, the JavaScript in the page can stretch the image immediately after the resize, and then redraw the seam carved image as soon as the server returns it. At the server side, instead of reading the original image on every request, it can be cached. The result images with a step of an optimal values can also be cached to enable faster replies by the server.
I am still trying to host it by writing a PHP version and hosting it. Will post the link as soon as that is complete.