This is a beta version of migrating these workshop materials to a new platform. If you run into issues please file an issue or click on the edit link above and submit a pull request. You can use the previous version of the workshop materials as a fallback.
If you’ve decided to deploy an image server, you’ll probably want to create an access derivative source image which is separate from your master preservation version of the image.
Picking a source image involves various trade-offs including the following:
One advantage of using an advanced image server is that various sizes of images do not need to be precomputed and as your web site design changes the image server can dynamically create the appropriate sizes.
Some institutions create a JPEG2000 image for their source image. JPEG2000 images can be highly compressed while still allowing for good quality and fast seeking into the image to extract regions for tiles. While there is an open source implementation of JPEG2000, currently the fastest tool for creating and decompressing JPEG2000 images is Kakadu which is proprietary, so not suitable for some institutions.
While TIF has open source implementations, the images will take up more storage space and depending on the may be slower to extract a version of the image.
As JPEG2000 is a more complicated format than many others. It uses advanced techniques for compression.
#todo:0 provide instructions for how to create a JPEG2000 image with Kakadu
#todo:0 Creating a JPEG2000 Image with OpenJPEG
See the page on static image servers for an example of how to create a static, Level 0 implementation.