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Writing TIFF Output File Using ImageIO File in Java

I have a large number of frames that should be placed together on a large image (for example, in a mosaic). Required image positions are required.

There are a very large number of images, so loading them into memory is impractical at best.

Based on some other answers here, I was able to override the methods in RenderedImage (specifically getData(rect) ) to load into the appropriate data and return.

This works fine, however the image author always calls getData and requests a row of data. It seems to me that I should be able to modify ImageWriterParam to call individual tiles instead, but when I tried, the write function still calls a single line from getData .

How can I get this to use tiles and call getTile instead.

 BufferedOutputStream bos=null; try { bos = new BufferedOutputStream(new FileOutputStream(new File("test2.tiff"))); ImageWriter writer =(ImageWriter) ImageIO.getImageWritersBySuffix("tif").next(); ImageOutputStream ios=null ios = ImageIO.createImageOutputStream(bos); writer.setOutput(ios); ImageWriteParam param = writer.getDefaultWriteParam(); param.setTilingMode(ImageWriteParam.MODE_DEFAULT); RenderedImage mosaic = new MosaicImage(imageFiles[]); writer.write(null,new IIOImage(mosaic,null,null),param); } catch (FileNotFoundException ex) { }

Note. I can use param.setTilingMode(ImageWriteParam.MODE_EXPLICIT); and setTiling(w,h,xoff,yoff);

However, when using writer.write , it still calls getData(rect) in my image and very annoyingly does not call the rectangle of the size specified by w,h . It calls a rectangle of size, which differs by a random amount (perhaps comes from something)

For example, if I use setTiling(100,100,0,0);

one would expect that even if it does not call getTile from the image, the Rectangle passed to getData should be (0,0,100,100), but instead it passes a Rectangle (0,0,96,96) which is not a multiple of the image width or anything else i can think of.

Thanks for any help

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java tiff tiles javax.imageio
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If you read the TIFF 6.0 specification in the TileWidth and TileLength fields, you will find the text

TileWidth must be a multiple of 16. This limitation improves performance in some graphics environments and improves compatibility with compression schemes such as JPEG.

And similarly for TileLength. 100x100 is not divisible by 16, but 96x96 is, in my opinion, a TIFF encoder that is struggling to fulfill your request.

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