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#46 |
Well trained by Cats
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#47 |
Resident Curmudgeon
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Seems nobody cares that you can lower the size of the ePub by reducing some of the crud in the graphics without changing the quality of the graphics at all.
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#48 |
eBook Enthusiast
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If you reduce the size of a JPEG file you are discarding information. The result may look very similar, but it's incorrect to say that you're not "changing the quality of the graphics at all". Having said that, you can discard a LOT of information from a JPEG file without noticeably changing its visual appearance.
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#49 |
frumious Bandersnatch
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Some changes can be lossless, if done correctly with the correct tool: Discarding metadata, optimizing compression, removing color information in greyscale images (not exactly lossless, but lossless in practice), cropping extra margins...
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#50 |
Resident Curmudgeon
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The method I mentioned edits the jpeg information without changing the pixels. The result is possibly a smaller file with no loss of quality. For example, Photoshop is known to put stuff in the jpeg file that can be stripped out without any loss to the image. An iPhone can put in location information that can also be stripped out. There's a lot of junk in there that's not needed and just makes the file size larger.
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#51 |
Grand Sorcerer
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jpegtran can also losslessly flip and rotate.
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#52 |
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#53 |
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I mean, I am sure there's a lot of bloat to cut here, but in practice going through all my books and dicking with the image files is frankly never going to happen :-)
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#54 |
Resident Curmudgeon
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Then obviously, the file size of your ePub doesn't matter to you. So why start this thread if that's the case?
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#55 | ||
Wizard
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Quote:
Quote:
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#56 |
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Thank you, Shalym :-)
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