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In contrast to the internal PDF comparison of Adobe Acrobat Pro and similar tools, Eagle Eye utilizes a pixel-based approach. This way, not only changes in the text but also minimal spatial differences such as tiny shifts, image retouchings or deviations in spacing are recognized.

When revising print data or converting print projects from one InDesign version to another or changing platforms from Mac to PC, it is crucial to ensure that PDF files stay unchanged. Here, simply comparing the texts will not do the job. Close attention must also be paid to hyphenation, positioning of objects, correct font usage and possibly missing/changed glyphs.

Eagle Eye compares your data pixel by pixel and raises alarm as soon as an image dot is out of line.

No, Eagle Eye matches PDF files only. In many cases, however, it is possible to convert the files you want to compare into PDF documents beforehand and then there is no stopping you.

Both files must have the same number of pages and the same page format; in addition, the content must be on the same page in each file to be compared (i.e. the content on page 5 of PDF 1 must also be on page 5 of PDF 2).

If the two files have different amounts of pages or formats you can work with the settings for each individual PDF where you can limit the number of pages to be analyzed and define the page format manually.

Yes, in some cases you may want to increase the tool’s tolerance for differences between pixels so you get a more meaningful result. There are different options to do so which can be defined in the general settings and can also be combined with each another:

  • ~ Resolution: The lower the resolution, the more coarsely the comparison objects are processed and analyzed.
  • ~ 1 pixel tolerance: This option helps to ignore minimal differences, e.g. in kerning or ligatures.
  • ~ Gray scale tolerance: The higher the tolerance, the more generously deviations in gray scale and black sections are ignored.

Eagle Eye essentially superimposes the individual PDF pages to show the pixel deviations between the compared pages. Therefore, PDF documents whose breaks differ significantly across pages are not suitable for a comparison, as in this case an assessment of the analysis result is not helpful.

This phenomenon can have various causes:

  • ~ The PDF files were created with different export settings.
  • ~ The colors were converted when one file was exported; this was omitted when the other file was exported.
  • ~ Different compression methods were used for the images.
  • ~ The maximum resolution has been changed from one version to the next.

It may happen that the tool comes to a standstill due to the complexity of the files that need to be analyzed. This may be caused by the fact that the documents contain a large number of pages or graphics that are composed of many individual elements.

Here, it is advisable to split the documents into several files.

As infallible as the eye of our tool may be, as deplorable is its memory. We do not archive PDF files or images. When you upload your PDF documents to our server for analysis, we store the files for 24 hours. After this, they will be irrevocably deleted.

Server location in Germany
Our server is locaded in our company building in Kempten. We do not use any external cloud providers to store or process your data. Your data will not be backed up either as the production data for the comparisons is (temporarily — see above) saved in a directory separate from the software.

Transfer and dissemination
The transmission of your documents is encrypted end-to-end using the HTTPS protocol and is therefore protected against interception. In addition, we do not pass on your data in any way. Your orders never leave our company.

File name
In the course of the upload, the file names of your PDF documents are replaced by randomly generated keys so no conclusions about the content can be drawn from the file names. Only these keys are saved in the log files and databases of Eagle Eye to identify an order.

In-house server access
Data protection is taken very seriously within our company. Access to the Eagle Eye server for maintenance and service purposes is granted to our IT staff in the specialist department only. There is no disclosure of data to third parties, e.g. in response to a telephone request.