User:Lhamilton/drafts/Draft PP Image Size

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Preparing illustrations for the HTML version

.... (light yellow and strikethrough indicate changes)

Image sizes

There are two ways to include images in your book -- either directly as "inline" images that will display directly on the HTML page or as a "linked-to" images that are included in your images directory but are accessible to the reader only by clicking on a link present within your HTML.

For information about the size of Cover Images, please read the #Cover Image section of this document. Linked-to images are not accessible in the epub or mobi versions of the book so should not be used instead of inline images.

Inline Images

Inline images should be no larger than 256Kb and may have dimensions up to 5000 x 5000 pixels. (eBookmaker, the Project Gutenberg epub/mobi generator, will downsize any image that is larger than the above limits in ways that are beyond our control, resulting in an unpredictable image quality.)

Inline should be sized sensibly. They should be no larger in terms filesize than necessary for the clear display of the image. In addition, their dimensions should fit reasonably with the text, with large images relatively large and small images relatively small. Please check your images for quality and size in the HTML and e-reader formats.

If an image of a map or detailed illustration needs to be larger than what can be displayed inline, you can either split it into smaller segments or include it as a "linked-to" image. As mentioned above, such images will not be included in the epub or mobi versions, only in the HTML version. Those linked-to images should be as large as necessary to be readable, but no larger. However, should these linked-to images be larger than 200 KB and/or more than 800 - 1200 pixels in width or height, please advise the PPVer or PG Whitewasher (if you have direct upload capability) of the reason for the large files.

In the past, some post-processors linked to large images from very small (100 or 200 pixel wide/high) 'thumbnail' images. That is no longer a good idea since links from such tiny smaller inline images to larger images do not work in the e-reader epub and mobi formats. Consequently, if you're linking from a smaller image to a larger linked-in image, please ensure that your inline image is large enough to look OK in the epub or mobi formats.

It is also important to check that you haven't inadvertently distorted your images by inappropriate use of HTML sizing code for the image. Such sizing, if specified in your HTML code, should be in em or percentage units rather than in pixels.

For more information, please review the Guide to Image Processing.

Linked-To Images

This type of image may be used for displaying images such as large complex maps that must be larger in size than an inline image.

When using this type of image, you should link the larger image from a normally-sized inline image. Images that are targets of an href should be no larger than 1Mb in size and may have dimensions of up to 5000x5000 pixels. For accessibility, the anchor tag for linked-to images should have a description of the image in the title attribute, and an id attribute to facilitate user navigation.

Cover image

You must include a cover image called cover.jpg (or, much more rarely, cover.png, if the image is appropriate as a "png") with your project.

Covers should be at least 650 x 1000 pixels (width x height) and may have dimensions up to 5000x5000 pixels. Larger dimensions are recommended. Cover file size should be no larger than 256Kb. If you specify image dimensions in your HTML code, please use em or percentage units rather than pixels.

As with regular illustrations, you should remove all major blemishes and rotation/distortion problems from the cover image. You should also remove any library code tags. Also, if your project has no cover, please do not include a cover from a different version of the book or created from stock images.

For more information about cover images and DP policy, please read the PP Guide to Cover Pages. If you would like to have another volunteer create a cover for you, simply post on the We've Got You Covered team area of the forums. You'll be asked to provide images from the book if they're available or possibly a copy of the title page.