When Acrobat Professional (Version 8 or higher) is used to convert PDF files to PDF/A, the ‘engine’ that carries out the ac-
tual conversion is the integrated Preflight plug-in. Even if the conversion is triggered using the Acrobat 8 export function or by Starting the Preflight tool: The command for opening the tool is lo- cated on the ‘Advanced’ menu.
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clicking ‘Save As’, the Preflight module is responsible for converting the file.
The Preflight module is opened from the Acrobat ‘Advanced’ menu or by pressing Shift+Ctrl+X.
The lower section of the main Preflight window immediately provides information on the status of the opened PDF file with regard to the PDF standard: Is the docu- ment PDF/A and/or PDF/X-compliant? (PDF/X is a prepress standard.) If the PDF
file was not created as a PDF/A, the user re- ceives a message telling him or her that the file is ‘not a PDF/A file’. If the user now wants to trigger PDF/A conversion, he or she can simply click the PDF icon.
The Preflight tool uses a dialog box to ask the user whether the existing PDF files should be converted to PDF/A-1a or to a re- stricted PDF/A-1b version.
Conversion to PDF/A-1b
In the first scenario, the user selects the ‘PDF/A-1b’ standard and sets the output condition to ‘sRGB’ in the dialog box. This indicates that the PDF in question is des- tined to be displayed on a monitor. Since the PDF file quite possibly already contains an output intent, the tool provides a check- box that specifies that the present intent is to be used. In addition, another checkbox prevents the embedding of the ICC color
profile if it is not required. This reduces the resulting file size.
When the user clicks the ‘OK’ button, the Preflight tool searches the existing PDF document to see whether it meets the pre- requisites for successful conversion to PDF/A. If the prerequisites are met, the conversion takes place. The green tick in this example shows that no problems oc- curred during the conversion. Details on the conversion process are shown in the Results window in the form of a list. The list contains information such as the fact that the tool added the file name suffix ‘_A1b’ to the source document.
Conversion to PDF/A-1a
The second scenario describes the conver- sion of a PDF file to PDF/A-1a. The proce-
dure is the same as for scenario 1 except that the compliance level ‘1a’ is chosen along with an output condition that is suit- able for four color printing (for example, ISO Coated).
Again, the Preflight tool checks that the relevant document meets the prerequisites for the conversion. ➔
Following the conversion: The Results win- dows shows the steps that were carried out and informs the user that the conver- sion was successful.
Preflight: The PDF/A icon is also a pushbutton that triggers conver- sion to PDF/A.
Preflight: The PDF/A conversion options relating to the level of the PDF/A standard (1b in this example) and the output intent.
PDF/A-1a: Conversion settings with an output intent for profession- al offset printing.
From PDF to PDF/A
In this second example, a red X clearly indicates that the conversion can- not be carried out suc- cessfully. Preflight uses the Results window to in- form the user of the prob- lems that occurred. An additional area below the list explains why the prob- lems that occurred pre- vent the document from being successfully con- verted to PDF/A-1a.
The file does not have the required MarkInfo entry. This error message is relatively common if the person generating the PDF has not structured the content of the docu- ment using tags before- hand. This structural in- formation is one of the
things required in order to define the text flow order for document layouts that have
multiple columns, images, and captions. In this example, the source PDF document must be re-exported from the source pro- gram either using different preparation methods/settings or repaired.
Direct selection of a profile
Experienced users can take advantage of a more direct way of selecting the required PDF/A test or conversion profile.
For example, they can choose to select one of the PDF/A profiles from the list in order to check a document for PDF/A suit- ability or, if possible, to immediately con- vert it to PDF/A-1a or PDF/A-1b using a specified output condition. The conversion profiles are all assigned one of the four most common output intents.
If the output intent required for a special workflow is not contained in the list, a new, modified PDF/A profile can be set up on the ‘Edit Profile’ screen.
The user selects the required profile for the verification or conversion from the list and clicks ‘Execute’. Processing can also be started by double-clicking the correspond-
ing profile name. ■
Profile list in Preflight: Both verification and conversion can be car- ried out using the delivered PDF/A profiles.
Conversion not possible: If the PDF file in question does not meet the prerequisites for conversion PDF/A, Preflight terminates the conversion process and provides the user with detailed information on the rea- sons for the failure of the process. For an extensive overview of these error messag- es, see the appendix.
For more information on inte- grating this structural informa- tion via tags either before or after conversion, see the ‘Acces- sibility’ chapter on page 50.