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JPEG2000 settings allow you to specify types and levels of compression as well as advanced settings for your JPEG2000 images, leaving your archival source images unchanged.

When importing tab–delimited text with full resolution files, JPEG2000 settings must be established before beginning the import process. Otherwise, JPEG2000 settings can be established before or during the Batch Add process.

To establish JPEG2000 settings during Batch Add:

1. Click Batch Add.

2. Specify the directory and files to import.

3. From the Full Resolution Settings dialog, click Advanced. The Image Optimization dialog opens.

4. Click Options. The Image Options Dialog opens.

5. Click the File Format tab.

6. Establish your settings and click Save in the Image Optimization dialog to retain your settings.

To establish JPEG2000 settings before importing images:

1. From your Acquisition Station project, click the Tools menu.

2. Select Image Optimization. The Image Optimization dialog opens.

3. Click Options. The Image Options dialog opens.

4. Click the File Format tab.

5. Establish your settings and click Save in the Image Optimization dialog to retain your settings.

To configure JPEG2000 mage settings:

1. On the File Format tab, select JPEG2000 from the File Type pull down list.



2. Choose a compression option. Compression options for JPEG2000 are lossless and lossy:

• Lossless compression: With lossless compression, all of the data originally in the file remains once the file is uncompressed for viewing. Using lossless compression produces larger file sizes.
• Lossy compression: Lossy compression results in some data within the file being permanently eliminated (although this is often undetected by users). Using lossy compression will produce smaller file sizes.

For lossless compression, remove the check next to Lossy compression.

For lossy compression, check Lossy compression and choose from one of two measures of compression:

• By compression ratio: 10:1 applies the least compression, hence produces a higher quality display image and larger file size. 100:1 applies the greatest compression, resulting in a lower quality display image and smaller file size.
• By quality: Minimum will produce the lowest quality image and smaller file size. Maximum will produce the highest quality image and larger file size.

To preview your compression settings, click OK to close the Image Options dialog. Click Preview in the Image Optimization dialog.

To change the settings, click Options.

If you are satisfied with your settings, click Save.

3. Click Advanced for additional JPEG2000 settings. Advanced settings provide a range of options for users who are familiar with the JPEG2000 standard and who have very specific configuration requirements. In most instances, the default settings will be adequate.



• Tile dimensions: CONTENTdm JPEG2000 images are divided into tiles for more efficient delivery of images. Each tile can be independently decoded, lowering the memory requirements for image decoding. Specifying small tile dimensions for use with very large images will result in less efficiency. The default tile dimension is 1024x1024 pixels.
• Resolution levels: JPEG2000 allows lower resolution images to be extracted from source images. Each resolution level is one-fourth the size of its predecessor. For example, a 1024x768 pixel image with four resolution levels supports the extraction of images (zoom in and zoom out) at 1024x768, 512x384, 256x192, and 128x96. The default setting, Auto, allows CONTENTdm to determine the appropriate number of resolution levels based on the pixel dimensions of each source image. The larger the image, the more resolution levels CONTENTdm will generate.
• Quality layers: The quality layers setting is encoded in JPEG2000 images for potential use in other applications and currently has no bearing on display images within CONTENTdm. Quality layers in JPEG2000 images contain data that contributes to the overall image. This layering of data allows lower quality representations of images to be displayed before the entire image has been decoded. As successive layers are decoded and made available they contribute data to form higher quality images. The default setting is 20 layers.

4. When you have finished establishing your settings, click OK to close Advanced JPEG2000 Settings. Click OK to close the Image Options dialog.

5. Click Save in the Image Optimization dialog to retain your settings.

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