you better read the picture from a File thus it will be easier to cache data. I mean there are many ways to load pics in Java, but the File mode still acquires less memory.
You got ImageIO.setUseCache
to get File caching
while using image streams. Plus you can use the new JAI imageio Streams Channels
to buffer data etc.
Hence you should check your code for different ways of loading pictures for your textures BEFORE you can transform them. And it is a good idea to check for a data buffer Manager like the MediaTracker
for your renderings in Jogl.