02-24-2011, 01:22 AM | #1 |
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Images in EPUB books
Hello all,
I have been wondering about this thing and can't seem to find an answer: If I include a JPEG image into my EPUB book, how is it processed by ebook readers? DO they scale the image to fit the page or what? I always tend to resize the images so that the fit 600x800px matrix, but I would love to understand how readers process the images in EPUB files. Thanks in advance! |
02-24-2011, 03:43 AM | #2 |
frumious Bandersnatch
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They obey the CSS styles. If there is no width/height specified, I guess most default to the "natural" size: 1 image-pixel = 1 screen-pixel. Some readers may allow zooming an image, but most don't, and just crop the image if it doesn't fit the screen.
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02-24-2011, 05:37 AM | #3 |
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Is it safe to presume all e-ink readers are about 600x800 in resolution? If I crop the image so that the width or height don't go beyoung the 600x800 resolution...
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02-24-2011, 06:00 AM | #4 | |
frumious Bandersnatch
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Quote:
1) There are non-e-ink readers with smaller resolutions (smartphones, PDAs...) 2) Most readers have default margins and headers or status bars that occupy part of the screen (and sometimes cannot be disabled). |
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02-24-2011, 06:11 AM | #5 |
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I notice the Kobo just makes the image fit the screen - so if too big it compresses it into small size, Maps suffer with this as they are too small to read. I always check that images are neither too big or at too high resolution as they can slow down devices and create over large documents. This is OK on a computer but might not be appreciated by someone downloading it to their phone. Unless you really need an image at incredible clarity a hi res huge image is a waste of space.
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02-24-2011, 11:54 AM | #6 |
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The Hanlin eBook readers all reduce too large images. Small images are shown at 100% at level one zoom and will enlarge as zoom increases although they will not increase too much. If a graphic is being used as a letter for example, it will zoom when the letters zoom. This is ADE implementation. Most ADE implementations behave similarly except Sony as remained with an older version for many (most) of its models.
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02-24-2011, 04:45 PM | #7 | |
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Quote:
(And a separate Kindle cover 600x800 to allow for the kindle conversion.) Then in the CSS the images are sitting on a .img {max-width: 100%} problem solved. Although Lately I've been making the height to be 100% instead of the Width... |
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02-24-2011, 09:00 PM | #8 |
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when I asked the IT guy here to check the book on his android phone all images over 450 wide defaulted to a question mark icon. I think I'll take up Adjust's suggestion and fix it in the CSS.
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03-02-2011, 06:14 PM | #9 |
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Mark,
Which 'droid based phone was that? |
03-02-2011, 06:26 PM | #10 |
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03-02-2011, 10:12 PM | #11 |
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Thanks.
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03-03-2011, 04:54 AM | #12 |
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That's a bug in that particular reading application; it really should not do that.
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03-03-2011, 07:12 PM | #13 |
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03-04-2011, 02:36 AM | #14 |
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03-04-2011, 04:26 AM | #15 |
frumious Bandersnatch
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