How do 'Optimize profile' (optimization) settings affect my files?

Default Optimize Profiles

NXPowerLite v10 ships with three Default optimize profiles. 

Balanced

This is suitable for most purposes and offers a good trade-off between file size reduction and the quality of the content of the file.

Strong

This is useful if you have tried Balanced and you are less concerned by quality and want to try and make the file smaller. 

Basic 

This is when the output quality needs to be good. For example, when the file needs to be suitable for high-quality printing or for viewing on high-definition screens.

The settings that are different in each profile are listed below:

Custom Optimize Profiles

It is possible to create a custom optimize profile for a specific purpose. For example, if you want to have a profile that resizes JPEGs optimized for display at 1080p.

In the main dialog,  select either New optimize profile... from the Optimize profile drop-down or Manage profiles... from the Edit menu option. Any new Optimize profile will default to the settings in the Balanced profile.

Once you have configured your settings make sure you give your custom profile a descriptive name, so that you can easily select it from the drop-down on the main dialog.

Optimize Profile settings

JPEG Quality

This sets the level of quality used by NXPowerLite when recompressing JPEG files. The scale runs from 1-9:

• "JPEG Quality 1" will result in greater file size reduction but will reduce the visual quality of images. 

• "JPEG Quality 9" will fully preserve image quality but will result in less reduction.

We recommended using our default settings because these offer an excellent balance between file reduction and quality.

Please note: The JPEG Quality setting for both PDF and Microsoft Office files refers to the JPEG images stored within the file. NXPowerLite does not resize stand-alone JPEG files in any of the standard profiles. It can be configured to do so in a custom profile by enabling the resize setting.

Resize images for display at:

Documents often contain very large images, taken with digital cameras for example, which contain far more visual information than will ever be seen by a user in normal use. NXPowerLite can scale these images down to target a particular display resolution. If you need to target a specific DPI setting for Word, Excel or PDF files - please refer to this article that explains how to translate display resolution settings to DPI.

Delete Private Application Data (PDF)

Applications that create PDFs files, such as Adobe Photoshop or Acrobat, are able to store information within a PDF file that they can use when opening or editing the file. This information can only be used by the application which created the file and is not needed to display a PDF file. For most cases, we recommend deleting this data as it will have no effect on the use of the PDF file.

Subset Embedded Fonts (PDF)

Enabling this feature means only those characters that are actually used in the layout are stored in the PDF. If the “$” character doesn’t appear anywhere in the text, that character is not included in the font. This means that PDF files with subsetted fonts are smaller than PDF files with embedded fonts.

Delete cropped areas of pictures (Microsoft Office)

Enabling this feature will trim cropped images within documents so that only the visible portion is stored in the file. This will reduce the size of the files, but users will no longer be able to edit cropped images to reveal the areas that have been removed.

Flatten embedded objects (Microsoft Office)

Enabling this feature will cause embedded objects within Office files to be "flattened", converting them into pictures. This will reduce the size of the files but users will no longer be able to double-click embedded objects to edit them.

For example, a PowerPoint presentation may contain an embedded Bitmap graphic. Doubl-clicking on that graphic would open the image inside Paint for editing. After NXPowerLite has flattened embedded objects this will become an image and cannot be double-clicked to edit.

To optimize files without "flattening" embedded objects create a custom profile with that settings disabled.

Reduce color depth of PNG images

When this feature is enabled NXPowerLite will reduce the number of colors used in PNG images within Office files, where it is appropriate. This method is called quantization and while it is a lossy process, compressed images look the same as the originals. NXPowerLite uses the same approach for standalone PNG images.

Optimize images on slide masters (Microsoft PowerPoint only)

It is possible to select whether or not images that appear on slide masters will be optimized. If this setting is enabled then all images in the PowerPoint will be optimized. If it is disabled NXPowerLite will not process images that appear on slide masters.

Remove embedded Excel data from charts (PowerPoint and Word only)

When charts are inserted or copied into Powerpoint or Word from Excel the whole Excel file will be embedded in the file. NXPowerLite can remove those usually bulky embedded Excel files but ensure that the data required for the chart is still editable. 

This setting is off by default but can be enabled if you create a custom profile.

Maintain compatibility with Word 2007 (Word only)

Microsoft built backward compatibility into any files created in Office 2010 onwards so that they could open in Office 2007. The effect on the file is to treble the size of any image-related content in the file. This setting is enabled by default in all our default profiles as there are not many users still using Office 2007.

If you have users still using Office 2007 then create a custom profile with this setting disabled.

Clean excess cell formatting (Excel only) [Not available on macOS]

Excessive cell formatting occurs within Excel files when ALL of the blank cells in a sheet have individual formatting applied. This can be hard to see when just looking at a sheet as the formatting could be setting the colour of the font to use for example, but there is no text.

This can create some incredibly large Excel files that to the casual observer appear to have very little content. NXpowerLite can clean this excess formatting without affecting the data in the file. In some cases, this results in a significant reduction in file size. One customer example file we saw reduced from 91MB to 31Kb!

Remove EXIF data (JPEG)

JPEG images normally include extra information (metadata) inside the file such as: Device on which the image was taken or the location the image was taken plus many more. By default NXPowerLite will retain this data however, this option enables this data to be removed from each JPEG file. In v10 onwards, the Orientation EXIF property is always retained and not deleted.

Note: Currently there aren't any optimization settings for PNG or TIFF files.