Below is a list of  each of the PDF optimizer settings and a description of their functions.

Image Processing

Image Compression Choose to either retain or convert any image to either a JPEG, JPEG2000, FLATE, or JBIG2.

  • JPEG – lossy compression that will reduce image quality and size
  • JPEG2000 – less lossy compression that will reduce size and some quality
  • FLATE – Lossless compression does not reduce quality but may not always reduce file size
  • JBIG2 – Lossless compression that can only support black and white color space. Color images will be converted to black and white. Best for scanned documents with no images

*Note – Anytime a change is made to “Color Space” or “DPI” the image will have to be re-compressed. When the “No Change” option is selected, PDF Studio will attempt to keep the current image compression format. If it is not supported, PDF Studio will re-compress to the closest matching supported compression.

Image Quality Allows the image quality to be adjusted between 10-100%.

  • This will only affect JPEG or JPEG2000 images as these are the only formats that support image quality settings.
Image Color Space Choose to either retain or convert the image colors to Grayscale or B&W.

  • Grayscale – Only supported with JPEG, JPEG2000, or FLATE. Best for full color images
  • B&W – Only supported by FLATE or JBIG2. Best for scanned documents with no images

*Note – When the “No Change” option is selected, PDF Studio will attempt to keep the current image color space. If it is not supported, PDF Studio will change to the closest matching supported color space. JPEG images with CMYK color space will be converted to RGB due to a regression bug in JDK 1.7.

DPI (Dots per Inch) Resolution Adjust the image resolution of all images that are larger than the option selected

  • Preset options include retain, 50, 100, 150, 200, 300, & 600 DPI
  • Custom option allows user to set any value between 50-1200 DPI

 

Object Removal

Alternate Images Removes alternate embedded image dictionaries that are used for high resolution printing to reduce file size. Only visible images displayed on the PDF while viewing will be kept in the document.
Bookmarks Removes all bookmarks from the PDF document
Document Info Removes any document information located in the document properties (Document->Document Properties) that would include the following:

  • Title
  • Author
  • Subject
  • Keywords
  • Producer
JavaScript Actions This will remove all JavaScript actions from the PDF document but retain any objects that may have had JavaScript actions such as form fields, push buttons, etc…
Embedded Thumbnails Removes page thumbnails that are stored in the PDF document. Once removed the page thumbnails will just be rendered each time the document is loaded.
Comments Removes all annotations and comments from the PDF document
Links Removes all links from the PDF document
Attachments Removes any attachments that are stored within the document
Form Fields Removes all form fields that are on the PDF document
Metadata Removes all additional or extra Metadata from the PDF Document
Unused Resources Removes resources that are located within the document but are never referenced by any objects in the PDF document.

Other Options

Flatten Comments Flattens all annotations including text boxes, shapes, highlights, and stamps directly onto the document so that they can no longer be edited.

  • Annotations such as the sticky note will have comments removed but the image will still be placed on the document
Flatten Fields Flattens all fields including text boxes, check boxes, radio buttons, combo boxes, list boxes, buttons, & signature fields directly onto the document so that they can no longer be edited. All values within the fields will be flattened as well
Merge Duplicate Images Merges any duplicate images within the PDF so that all objects are referencing the same image resource rather then multiple of the same resource
Merge Duplicate Fonts Merges any duplicate fonts within the PDF so that all objects are referencing the same font resource rather then multiple of the same resource
Compress Uncompressed Streams Compresses any additional PDF elements within the document such as page descriptions that have not been optimized by any other process to further reduce file size
Clear Signatures Removes all signatures that are on the PDF Document but will leave the signature field