Large dimensioned images lead into an OufOfMemoryException

I am using OpenMap and have to load very large dimensioned images.

I tried to load these images as big raster which fails wi开发者_如何转开发th an OufOfMemoryException. In debug mode the layer constructor tells me that the image dimensions are too large.

In an OpenMap mailing list I found the MyJAIPlugin, which allows me to load and display GeoTiff files.

How can I show a 300mb GeoTiff in OpenMap?

I had a nearly same situation by loading hd maps with at least 690mb filesize.

I also used the JAIPlugIn from the mailing list and internaly they use the OMScalingRaster witch works with a BufferedImage. These limits your image size and causes the debug message.

I've solved it by modifieing the OMScalingRaster. I've changed the BufferedImage to a TiledImage to handle large images and fixed the upcoming errors. Here it's important you change the scaleTo(Projection thisProj)-method, to scale with JAI.

Now i can load the file and it's rendered on the map. But if you are zooming out too much, it will throw a OutOfMemoryException because in my modification i make a subimage of the part of the image that will be visible and give it as BufferedImage to the OMRaster.

Here is the mod. at the end of the scaleTo-method:

            // Now we can grab the bit we want out of the source
            // and
            // scale it to fit the intersection.

            // Calc width adjustment
            float widthAdj = (float) ((double) iRect.width
                    / (double) clipRect.width);
            // Calc height adjustment
            float heightAdj = (float) ((double) iRect.height
                    / (double) clipRect.height);

            // Create the transform
            // JAI-Version
            ParameterBlock pb = new ParameterBlock();
            pb.addSource(sourceImage.getSubImage(clipRect.x,
                    clipRect.y,
                    clipRect.width,
                    clipRect.height).getAsBufferedImage());
            pb.add(widthAdj);          // The xScale
            pb.add(heightAdj);          // The yScale
            pb.add(0.0F);           // The x translation
            pb.add(0.0F);           // The y translation
            RenderedOp newImage = JAI.create("scale",pb, null);

            bitmap = newImage.getAsBufferedImage();


            point1.setLocation(iRect.x, iRect.y);
            // setVisible(currentVisibility);
        }
    } else {
        bitmap = null;
    }
}

For the other errors by replacing BufferedImage with TiledImage use the equivalent TiledImage-methods. But to save memory you should use the TiledImage-constructor with the sharedDataBuffer flag = true.

For Exsample this mod. can handle maps (compressed 690mb) with a scaling of 1:50000 and i can zoom out to 1:600000 before the layer says it run out of memory.