MobileRead Forums - View Single Post - Possible suggestion on getting Nook Color to recognize covers

shaez · 01-22-2011, 10:11 AM

Hi everyone,

I just took my text editor, the good old zip/unzip commands and epubcheck program, comparing the EPUB files of two DRM-free books, one which displayed its cover thumbnail perfectly on my NC, and the other which did not.
After one hour of fumbling around, I could display reliably cover thumbnails on the Nook Color. Here is the method I used, in case you want to modify your EPUB by hand (it took me ~2 minutes per book, once I figured it out). This might also come handy for people writing EPUB gen SW for the nook color.
My nook color is not rooted and uses the 1.0.1 firmware.

In the OPF file metadata section, add one line saying

<meta name="cover" content="cover"/>

In the OPF file metadata section (assuming your cover image is in the images/cover.png file).

<item id="cover" href="images/cover.png" media-type="image/png"/>

The cover page does not have to be in the same folder as your OPF (but it can, I tried it).
I tried with png images and jpg images. For jpeg, both the .jpg and .jpeg extensions work.

Actually, the NC would stubbornly refuse to display the thumbnail of one file ("The wind in the willows" I got from feedbooks) unless I override the images/cover.png file by my own after doing the mods listed above. JPG would just not work for some unknown reason.

One thing to take care of when you do this: in some cases, there might already be an item with the id "cover" in the OPF file - usually it points to the xhtml of the cover page. When this occurred, I just renamed the id of the original cover item from "cover" to "cover-page", and updated the <spine toc="ncx"> section of the opf file to match the change.

I also tried a few variations on the metadata, changing the "name" and "content" attributes to various other names like cover-image, cover-illustration, etc., but only "cover" seems to do the trick. Too bad - I hoped I'd be able to use the unofficial recommendations found at http://blog.threepress.org/2009/11/2...-cover-images/ since it seems there is still nothing in the EPUB standard for covers - but actually the files I checked that seem to follow these recommendations do not have their cover thumbnail displayed.

01-22-2011, 10:11 AM	#41
shaez Junior Member Posts: 1 Karma: 10 Join Date: Jan 2011 Device: Nook Color	... manually modifying the EPUB files to have them display the cover thumbnail Hi everyone, I just took my text editor, the good old zip/unzip commands and epubcheck program, comparing the EPUB files of two DRM-free books, one which displayed its cover thumbnail perfectly on my NC, and the other which did not. After one hour of fumbling around, I could display reliably cover thumbnails on the Nook Color. Here is the method I used, in case you want to modify your EPUB by hand (it took me ~2 minutes per book, once I figured it out). This might also come handy for people writing EPUB gen SW for the nook color. My nook color is not rooted and uses the 1.0.1 firmware. In the OPF file metadata section, add one line saying <meta name="cover" content="cover"/> In the OPF file metadata section (assuming your cover image is in the images/cover.png file). <item id="cover" href="images/cover.png" media-type="image/png"/> The cover page does not have to be in the same folder as your OPF (but it can, I tried it). I tried with png images and jpg images. For jpeg, both the .jpg and .jpeg extensions work. Actually, the NC would stubbornly refuse to display the thumbnail of one file ("The wind in the willows" I got from feedbooks) unless I override the images/cover.png file by my own after doing the mods listed above. JPG would just not work for some unknown reason. One thing to take care of when you do this: in some cases, there might already be an item with the id "cover" in the OPF file - usually it points to the xhtml of the cover page. When this occurred, I just renamed the id of the original cover item from "cover" to "cover-page", and updated the <spine toc="ncx"> section of the opf file to match the change. I also tried a few variations on the metadata, changing the "name" and "content" attributes to various other names like cover-image, cover-illustration, etc., but only "cover" seems to do the trick. Too bad - I hoped I'd be able to use the unofficial recommendations found at http://blog.threepress.org/2009/11/2...-cover-images/ since it seems there is still nothing in the EPUB standard for covers - but actually the files I checked that seem to follow these recommendations do not have their cover thumbnail displayed. Last edited by shaez; 01-22-2011 at 03:47 PM.