The PaperCept Conference
Management System
Pdf Test Help The Pdf Test checks the compliance of your pdf file
with the conference and publisher's requirements
Contents Running the test
Viewing and understanding the test results
File size
Page count
Pdf version compatibility
Page margins
Font embedding
Font subsetting
Type 3 fonts
Oriental fonts
Other issues
FAQ: Failed overlays
Running the test

To test your pdf file, follow these steps:
  1. Choose the conference for which you are preparing the file and click on "Next."
  2. Click on "Back" if you wish to return to modify your choice. Otherwise,
    1. Choose the type of submission that you are preparing from the dropdown list
    2. Select whether you are preparing the file for first submission or if this is a final submission of a paper that has been accepted for presentation at the conference
    3. Click on "Next"
  3. Click on "Back" if you wish to return to modify your selections. Otherwise,
    1. Use the "Browse" button to locate the pdf file that you wish to have tested on your computer
    2. Choose if you wish to run the basic pdf compliance test, or the full test. The full test includes the margin and searchability tests, and takes longer than the basic test.
    3. Click on "Upload." Wait until the test is completed. This may take a little time, especially if you run the full test
  4. Click on the "Back" button if you want to modify your choice or to upload a different file. Otherwise, inspect the test results.
Viewing and understanding the test results

At the top of the test results page you will see this information
  • The local file path on your computer of the file that you uploaded
  • The conference and sort of submission for which the file was tested
  • A statement whether or not the file is ready to be submitted
  • A reference to critical issues that prevent the file from being ready to be submitted, if any. These critical issues are marked in the rightmost column of the overview that occupies most of the page. Critical issues must be resolved before the file may be submitted.
  • A reference to other issues that require attention, if any. These issues are marked in the overview. It is highly recommended to resolve this issues as well. If these other issues are not resolved then your file may be returned to you with the request to attend to them. This especially applies to final submissions where the files need to meet high standards to be included in the proceedings of the conference.

The various pdf issues are described below

File size Please limit the size of your manuscript pdf file to less than 500 kB. Files larger than 2 MB are not accepted for upload.
Page count The page count of your submission may be subject to a page limit, depending on the conference. Again depending on the conference, papers that are too long may be subject to an excess page charge. Consult the conference website for information.
Pdf version compatibility If your pdf file uses very recent pdf features then users with older pdf viewers may not be able to view and print your file properly. Make sure that you configure the application that you use to produce your pdf file so that your pdf is compatible with the conference requirement.
Lowest acceptable pdf version Some publishers do not accept early pdf versions. The conference submission system uses third party software to imprint the pdf files that are submitted with a time stamp and other information. This software does not support pdf versions below 1.3. Please use the most recent compatible pdf version.
Paper size Most conferences require the paper size of your submission to be either A4 or US Letter. Each page is individually tested for paper size.
Page margins

Most conferences impose requirements on the page margins. This is for uniform appearance, but also to leave sufficient space for supplementary information that is included in the proceedings, such as copyright information, paper identification and page numbering. Do not include your own page numbering.

The pdf test checks the margins by determining if the prescribed margins are blank, with a certain tolerance. If there are margin impositions you will see a report such as

Margin impositions:
Page 2 has margin impositions
Page 3 has margin impositions
Page 4 has margin impositions
Consult the Pdf Test Help
Download your file overlaid with border templates for inspection

Click on Download to download a copy of your file where on each page a gray rectangle has been overlaid that marks the required text area. Bookmarks indicate the pages where margin impositions were detected. Pages whose paper size was not recognized are not overlaid.
Searchability Most pdf documents are fully searchable. This is a valuable asset because it greatly improves the accessibility of a document, especially if it belongs to a large collection of documents. It is in your interest as author that your document is searchable.

Some pdf documents cannot be searched. An obvious example is a pdf document that has been scanned from a paper document. Some other pdf documents are not searchable because of nonstandard encoding of the document text.

The pdf test of the conference system checks for searchability by extracting the document text from the file and testing it for the occurrence of the common English words 'the', 'of', 'and', 'to', 'in', 'that' and 'is'. If there are a sufficient number of occurrences then the document is assumed to be searchable. If there are few or no occurrences then the document is marked as possibly being nonsearchable. It nevertheless may be searchable by Adobe Acrobat, Acrobat Reader and other pdf reader applications even though encoding is nonstandard.

If your file is reported as "This document may not be searchable" then please open it in Acrobat, Acrobat Reader or another pdf reader that supports searching, and check manually if the file is searchable. If it is, accept our apologies for the false alarm and upload the file.

If you find your file to be nonsearchable then if you upload the file and searchability is a conference requirement it is likely that the file will be returned to you for reformatting. In this case we recommend using a recent version of up-to-date software to convert your source document to pdf as described in the support section.

Font embedding

Every pdf document with text uses fonts. The pdf format allows to embed fonts within the pdf document. If a font is embedded then the viewer can display and print any text based on this font correctly. If a font is not embedded then the viewer looks for a substitute font on the computer where it is installed that is similar to the original font and uses this. The similarity may not be complete. For this reason publishers of pdf documents that are to be published and distributed electronically often require that all fonts are embedded.

An exception is sometimes made for the "Base 14" fonts of Adobe because they are considered to be widely available. These are the fonts Times-Roman, Times-Italic, Times-Bold, Times-BoldItalic, Helvetica, Helvetica-Oblique, Helvetica-Bold, Helvetica-BoldOblique, Courier, Courier-Oblique, Courier-Bold, Courier-BoldOblique, Symbol and ZapfDingbats. Even if these fonts are not available then they can often safely be substituted by similar other fonts.

The pdf test detects all fonts used by the document. Non-embedded fonts that need to be embedded are reported. The report includes the pages on which the fonts are used and also any graphics that use the font. Graphics are identified in the format Graphics4.2, that is, the second graphics on page 4. The ordering on the page is as the test finds the graphics. Note that not all graphics are identified as separate objects. Some graphics are embedded within the text.

Consult the support section on how to make sure that the required fonts are embedded.

Font subsetting

When a font is embedded within the pdf document pdf supports the option to embed only those characters from the font that are actually used in the document. This is called font subsetting. It reduces the size of the pdf file. Some publishers require all embedded fonts to be subset.

The pdf test detects all fonts that are non-subset embedded. Consult the Support section on how to make sure that embedded fonts are subset.

Type 3 fonts

Type 3 fonts are based on a sampled image representation and not on a vector representation like other fonts. They are not scalable and do not always view and print well. Their use is not recommended for high-quality documents and this is why Type 3 fonts are often not accepted.

The pdf test detects all fonts used by the document. If Type 3 fonts are not allowed and any are detected then they are reported. The report includes the pages on which the fonts are used and also any graphics that use the font. Graphics are identified in the format Graphics4.2, that is, the second graphics on page 4. The ordering on the page is as the test finds the graphics. Note that not all graphics are identified as separate objects. Some graphics are embedded within the text.

Consult the support section on how to avoid the use of Type 3 fonts.

Oriental fonts If a pdf document uses Chinese, Japanese or Korean fonts then oriental language support may be required to read or print the document. To make the document accessible to the widest possible audience the use of oriental fonts in an English language document should be avoided.

Consult the support section on how to avoid the use of oriental fonts in an English language document.

Encryption If some or all privileges for opening and editing a pdf document have been password protected then parts of the document are encrypted. The pdf test does not support encryption and encrypted documents are usually not accepted for conferences.
Annotations Pdf annotations are special document features such as links and form fields. Annotations cannot always be printed and therefore usually are not acceptable for conferences. Moreover some types of annotations may have attachments associated with them that potentially may carry viruses.

To avoid annotations turn off the conversion of Word features when converting MS Word files to pdf with PdfMaker. See the Support section on how to remove hyperlinks (which pdf considers annotations) when using the Save as PDF Add-in of Office 2007 and later.

Bookmarks Bookmarks affect the appearance of the document when it is opened and may not be allowed. Moreover, in electronic conference proceedings bookmarks are often added by the publisher for navigation and identification.
Other issues

In the section Other issues a link is available to optionally download a technical detailed report on the file that has been tested.

If the pdf test encounters a fatal error then this is reported in this section. Warning messages also appear here. The Fatal error messages and Warning messages that may be encountered are shown in the two tables below

Fatal errors
Error message Explanation
No file No file found
This document is encrypted This document is encrypted and was not processed
This is not a pdf file This is not a pdf file. The file was not processed
Cannot find the Root object

Cannot find startxref

No xref table found

Cannot find a cross reference stream

Cannot find cross reference table or stream

No trailer could be found

Page count error

Most likely the file is corrupted. It was not processed. If the file opens correctly in Acrobat or other viewers then please send us the file.

Cross reference stream: Unsupported decoding parameter

The file was not processed. Please contact support and send us your pdf file if you encounter this message
Parser error: Final search position x for page n does not agree with content stream length y The file was not processed. Please send us your pdf file if you encounter this message.
Warning Explanation
LZW decoding with early change is not supported "LZW encoding with early change" is a broken version of LZW encoding. It was used in Acrobat/Distiller version 3 and earlier and related products. Please use a more recent version of Acrobat/Distiller to compile your pdf file. You may also use Acrobat 6 Professional to convert LZW encoding to Flate encoding.
Page n has not been processed

XObject on page n has not been processed

One of these two messages follows the preceding warning
Warning: The right-hand margin may be reported inaccurately on page n because of a missing font widths table for the font Font Usually margin detection is not affected by this situation
Cannot find Info The file has no Info section
XObject of nonsupported type Type on page n

Font entry FontEntry in Graphics State dictionary on page n is not supported at this time

The Rotate parameter Rotate of page n is invalid

Please send us your pdf file if you encounter any of these messages
On page n the report of x sampled images is omitted because the smallest dimension of the image is less than 10 points This message may safely be ignored
Frequently asked questions

Failed overlays: After overlaying several pages of my file are incomplete and I receive error messages when I open the file in Acrobat

This problem is due to an incompatibility of the original pdf file. It looks as if especially pdf files prepared with dvipdfm suffer from this difficulty. Please consult the bookmarks of the file for information about the margin impositions. You may be able to repair the overlaid file by re-distilling it.