IFX Mail Archive: RE: IFX> Additional IFX Comments

IFX Mail Archive: RE: IFX> Additional IFX Comments

RE: IFX> Additional IFX Comments

From: Rick Seeler (rseeler@adobe.com)
Date: Fri Dec 20 2002 - 12:01:45 EST

  • Next message: Rick Seeler: "IFX> New Version of PDF/is Spec is now available (0.5)."

    My comments, below... (again)

    -Rick

    > -----Original Message-----
    > From: owner-ifx@pwg.org [mailto:owner-ifx@pwg.org] On Behalf
    > Of thrasher@lexmark.com
    > Sent: Friday, December 20, 2002 7:57 AM
    > To: ifx@pwg.org
    > Subject: IFX> Additional IFX Comments
    >
    >
    > Comment: 1
    > There are many optional "parameters" defined in the [pdf]
    > reference for various profiles or filters (both required and
    > optional for PDF/is) that we have not either made their
    > support discoverable by the creator or specified thier
    > support requirements.
    >
    > Example: The Gamma, BlackPoint and Matrix(for CalRGB)
    > entries in the colorspace dictionary(s) are optional in
    > CalGray/CalRGB.

    CalGray and CalRGB are no longer part of the spec, as stated previously.

    >
    > Comment/Question 2.
    >
    > Section 3.3.1.1.4 of PDF/is describes "Memory"....
    > In MBytes ???
    > Can we assume this is at least no more than what the
    > renderer returns in the pdfis-cache-size-k-octets-supported ?
    > Rounded down??

    I'll detail this further if we opt not to go with the proposal I detail at
    the bottom of this e-mail.

    >
    > The section mentions this being in addition to the 2Mbyte
    > base memory but I don't see any other mention of base memory.
    > (Should we assume this is a renderer
    > requirement???) What's is
    > this assumed to be used for???

    The spec says (In Section 3.3.1.1.4 of Version 0.5) "...the minimum amount
    of cache memory the Consumer (Renderer) will need to cache all objects
    necessary to render any particular page...". Is that not clear?

    >
    > Comment/Question 3.
    >
    > Section 3.3.11.3 of PDF/is describes "Banding"
    >
    > The section mentions that a document being created for an
    > unknown renderer should not use banding.

    This language was removed in Version 0.5.

    >
    > Considering that for interoperability purposes, a creator
    > would probably create a "least common denominator" file that
    > avoided optional parts of PDF/is if possible and used the
    > lowest resolution etc..... Is recommending/requiring that the
    > creator assume a 2Mbyte cache in the renderer and banding if
    > necessary such a huge problem???

    This is one of the questions I raised when I sent out Version 0.5. To
    reiterate:
    "Should we "hard code" a minimum buffer size for the memory cache value
    (Section 3.3.1.1.4) instead of making this another parameter?"

    I guess you (The Thrasher!) support the idea of making a fixed 'cache' size.
    In that case, all Producers would 'Tile' (Band) the Document, as
    appropriate, to fit within that memory requirement. If there are no
    objections to this, I will implement this in Version 0.6. The actual value
    of the fixed cache memory buffer will probably be adjusted once we implement
    a prototype.

    Thanks.
    -Rick

    >
    >
    >
    >



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