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Chris,
> On Aug 5, 2015, at 1:25 PM, Rizzo, Christopher <Christopher.Rizzo at xerox.com> wrote:
>> Dear PWG,
>> Before I get into the issue in the subject line - I'm wondering if, using my PWG account, it is preferable to go to the PWG web site and create a new issue tied to this document, or just email the issue to this group (so it can be vetted before an issue is created?) as I've done here?
Both work; new issues posted on the web site also get sent to the corresponding workgroup's mailing list, so either way we'll be able to look at it.
> I do not believe it is clear how the media-xxx-margin member attributes of the media-col collection are to be interpreted by a printer (Section 7.6 of PWG 5100.13). media-col is a Job-Template attribute, and the printer's physical margins are already reported by the printer in the media-xxx-margin-supported attributes of the Get-Printer-Attributes response. Since the printer already knows and reports its physical margin capabilities - why are these sent back to the printer as Job-Template attributes?
Because printers support both borderless and bordered printing, and that can affect print performance, scaling, etc. Also, some printers have different margins for 2-sided printing.
The expectation is that the client will supply supported media-xxx-margin values closest to what is required for the document being printed. For example, when printing a JPEG photo the client will likely specify media-xxx-margin values of 0 if the printer supports it, since that will result in borderless printing of the photo. However, when printing a cover letter the client will likely specify non-zero media-xxx-margin values to tell the printer that borderless printing is not intended, potentially resulting in faster printing without scaling.
> If the printer supports full bleed, then the printer already reports 0 for media-xxx-margin-supported.
>> Are these attributes instead intended to provide a modified boundary for marking the job on the page?
Not directly, however for scaling the margins define the output area.
> If so, how is the printer to respond if these margins are less than media-xxx-margin-supported values?
Clamp to the lowest supported values.
> How is the printer to respond if the client sends values are so large they overlap and theoretically result in a blank page?
client-error-attributes-or-values-not-supported or successful-ok-ignored-or-substituted-attributes.
> If scaling is also specified, how would that be related to margin values - should fit scaling be done to the specified margins?
Yes, assuming the margins are valid. The printer only has to support values it, um, supports. :)
> Does cropping need to occur?
For print-scaling='none' or print-scaling='fill', yes, but only to the printer's physical margins (optional to crop to the media-xxx-margin values).
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Michael Sweet, Senior Printing System Engineer, PWG Chair