Embedding Metadata | Photoshop CS Savvy

ImageReady can also embed metadata in your image files. What, exactly, is metadata? Metadata is data that describes other data. In the case of, say, a GIF image, metadata would be additional information, other than the actual pixel data, that describes the file, such as a description and copyright notice. ImageReady can embed this metadata within the GIF file itself.

Saving the Data

Let s take a look at how metadata is saved by ImageReady:

In ImageReady, open the file tomatoes.jpg from the ch26 folder on the CD.

New	To add metadata to the file, choose File ’ File Info to open the File Info dialog box. Click Description in the left column and add some text for Document Title, Author, Description, and Copyright Notice, as seen in Figure 26.29. When you are finished, click OK.

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Figure 26.29: Add some metadata to the file.

If the Optimize palette is not open, open it by choosing Window ’ Optimize. By default, ImageReady does not save metadata with your optimized images. To turn saving of metadata on, reveal the Options section at the bottom of the Optimize palette. Check the Add Metadata box, as shown in Figure 26.30.

Figure 26.30: Enable the saving of metadata from the Optimize palette.
Click the Settings button next to the Add Metadata box to open the Output Settings dialog box. Make sure that Add Custom ImageReady Metadata is checked, and all other options are not checked, as shown in Figure 26.31. Click OK to close the Output Settings dialog box.

Figure 26.31: Metadata output settings
Choose GIF 128 Dithered from the Preset list at the top of the Optimize palette.
Choose File ’ Save Optimized As to save your image. Name the new file my_tomatoes , and choose Images Only from the Save As Type list. Save the image. Leave toma toes.jpg open.
Choose File ’ Open Recent and select my_tomatoes.gif from the file list to reopen the file you just saved.
Choose File ’ File Info to review the embedded metadata. Notice that some of the metadata you typed in was not saved with the file. Only the Description and Copyright Notice appear, as shown in Figure 26.32. By default, these are the only pieces of metadata ImageReady saves with your optimized files.

Figure 26.32: By default, ImageReady saves only the description and copyright notice.
Close my_tomatoes.gif and return to the original file, tomatoes.jpg . On the Optimize palette, click the Settings button at the bottom of the Options section. This time, check the Add XMP Metadata option so it is selected. Click OK.
Choose File ’ Save Optimized As to save your image. Again, name the file my_tomatoes , and choose Images Only from the Save As Type list. Save the image.
Choose File ’ Open Recent and select my_tomatoes.gif from the file list. Choose File ’ File Info to review the embedded metadata. Notice that, this time, all the data has been saved with the file.

Note	In ImageReady, metadata is saved with optimized JPEG, GIF, and PNG files. It is not supported in WBMP.

Embedding metadata into a file naturally makes the file larger. Generally, you want the smallest possible optimized files. Metadata ( especially XMP metadata) can get quite large. If you just spent half the day optimizing an animated GIF to get it under the 64 KB limit your client requires, you don t want to add 16 KB of metadata.

To combat this problem, ImageReady gives you the option of saving your metadata as a separate XMP file that gets referenced in the HTML code it creates. So, instead of making each image larger, ImageReady abstracts the metadata and saves it in a format that s easy for a search engine to find.

Here s an example of HTML code that references an XMP data file called tomatoes.xmp :

 <html>  <head>     <title>Tomatoes</title>     <!-- copyright 2003 sybex -->     <meta http-equiv="Content-Type"           content="text/html; charset=iso-8859-1">  </head>  <body bgcolor="#FFFFFF" leftmargin="0" topmargin="0" marginwidth="0"        marginheight="0">     <!-- ImageReady Slices (tomatoes.gif) -->  <img src="tomatoes.gif" width="250" height="250" alt=""   xmpmetadata="tomatoes.xmp">  <!-- End ImageReady Slices -->  </body>  </html>

Understanding the Metadata Output Settings

When you check the Add Metadata option on the Optimize palette, ImageReady saves metadata with your image. You can control just what metadata is saved with your image by clicking the Settings button next to the Save Metadata checkbox, which gives you the following options:

Add Custom ImageReady Metadata Includes simple copyright and description information from the File Info dialog box.

Add EXIF Metadata Includes information stored with digital photographs, including camera type, date and time of photo, and file size . EXIF is supported only for JPEG files.

Add XMP Metadata By default, ImageReady saves only the description and copyright notice. Checking the Add XMP Metadata option enables you to include a wider range of data with your image.

Write Minimal Set of XMP Includes only a small subset of the complete XMP metadata set, including file modification and output times, file dimensions, and format.
Include Reference to Source File Adds to the XMP a block of information that points to the original document.
Write XMP to Separate Files XMP data for the file is written to a separate file, instead of being embedded in the image file.