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DynaPDF Manual - Page 56

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PDF/A and PDF/AX Compatibility
Page 56 of 750
PDF/A and PDF/X Compatibility
PDF files can be created for different purposes such as printing, publishing, or archiving which
have all their own requirements. Due to these different requirements two separate PDF
standards were defined by the ISO Committee, PDF/X and PDF/A.
PDF/X
The PDF/X-1a standard addresses blind exchanges where all files should be delivered in CMYK
(and/or spot colors), with no RGB or device independent (color-managed) data. This is a
common requirement in many areas around the world and in many print sectors - usually tied
to an environment where the file supplier wants to retain maximum control of the print job.
PDF/X 3 is like PDF/X 1a an ISO standard for graphic content exchange. The main difference is
that PDF/X 3 allows the use of color management and device-independent color in addition to
CMYK and spot colors.
The PDF/X standard requires all fonts to be embedded, the appropriate PDF bounding boxes to
be specified, and color to appear as CMYK, spot colors, or both. In addition, PDF/X compliant
PDF files must contain information describing the printing condition for which they are
prepared (see AddRenderingIntent()).
When creating PDF/X compliant files with DynaPDF you need to know that DynaPDF does not
check whether certain features are allowed to use in the selected PDF/X standard. DynaPDF
simply writes the required PDF/X key to the file which tells the viewer application that this file
is compliant to a specific PDF/X version. Whether this is true or not depends on whether you
used allowed features only and whether all required information were added to the file, e.g. the
rendering intent (see AddRenderingIntent()), the document title (see SetDocInfo()) and the trim
box for each page (see SetBBox()). It is usually best to check the resulting PDF file with a
preflight tool before using certain features in a production environment.
However, it is not very difficult to create PDF/X compliant PDF files. The main recommendation
is that all fonts are embedded, that at the least the trim box for all pages are set, and that colors
are defined in the color space DeviceCMYK (see SetColorSpace()). In addition, an ICC profile
must be embedded in the file (see AddRenderingIntent()) and images must not be compressed
with JPEG2000 compression.
The wished output PDF version must be set with SetPDFVersion().
 

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