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• • September 22, 2011 at 2:37 pm #60590
    David Gray

    Participant

    Has anyone else noticed that the InDesign CS5.5 ePub export exports the low-res proxy image for 72-dpi JPEGs if Image > Preserve Appearance from Layout IS checked . . . unless you set View > Display Performance > High Quality Display *before* importing a JPEG?

    The proxy image is the low-res preview that ID displays onscreen for placed graphics. It's much rougher than a 72 dpi JPEG would normally be if generated during the ePub export.

    I did not see this behavior in CS3 and CS4.

    If Image > Preserve Appearance from Layout is NOT checked, image quality is fine (though of course you lose any cropping, etc. done in the ID layout).

    This seems like a bug.

    Image below shows different results from ePub export with identical export settings (including Image > Preserve Appearance from Layout CHECKED). Only difference:

    LEFT: View > Display Performance > Typical Display [default setting]

    RIGHT: View > Display Performance > High Quality Display (set right before import).

    Note: Images imported with View > Display Performance > High Quality Display will STILL export the poor-quality proxy image if the document is closed, then reopened. You have to re-import the graphic with View > Display Performance > High Quality Display again before exporting to get the good-quality, non-proxy JPEG.

    

  • September 24, 2011 at 5:36 am #60602
    Anne-Marie Concepcion

    Member

    I'm sorry, but if you're seeing very different results in your images, then there must be something else going on — the images you export in an EPUB are not affected by the preview/proxy quality you choose in InDesign. I(And honestly, I can't tell from your screenshot which one is supposed to be worse or better than the other, though it might just be my old eyeballs… heh.)

    I can't duplicate your results. I placed the same high quality image 3 times into 3 separate files, and exported each to EPUB with the same image settings and same scaling applied. Before I exported, I changed the Display Performance preview for each one, so EPUB1 used Typical, EPUB2 used High Quality, and EPUB3 used Fast (just a solid gray preview).

    All images looked the same in my epub reader, and after extracting them from the epubs, each one was the exact same size (15.1 MB).

    ?

    AM

  • September 24, 2011 at 12:54 pm #60604
    David Gray

    Participant

    Hi Anne-Marie. Did your test use these settings in the ePub export:

    – 72 dpi

    – Image > Preserve Appearance from Layout?

  • September 28, 2011 at 8:55 am #60629
    Anne-Marie Concepcion

    Member

    I used the default settings of 150 ppi and Image > Preserve Appearance from Layout.

  • September 29, 2011 at 3:21 am #60632
    Rhiannon Miller

    Member

    I can see the difference between the two images. It's subtle, but you can see it, particularly on the grey text at the bottom ('CLEVELAND'S FAVORITE PRIVATE EYE').

  • September 29, 2011 at 4:55 am #60633
    David Gray

    Participant

    This happens when the original image is a 72-dpi image.

  • October 10, 2011 at 8:24 am #60728
    David Gray

    Participant

    More info: I determined that this problem occurs when image is:

    – JPEG

    – an ODD number of pixels wide

    This seems related to ID's resizing bug/feature related to 72 ppi images with EVEN number of pixels, discussed here:

    https://forums.adobe.com/messag…..04#1291804

    It does indeed seem related to ID's use of the ID-generated 72 ppi proxy image instead of the original 72 ppi JPEG.

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