MOBI > anything = formulas get magenta background

aodor · 11-16-2011, 11:52 AM

Hi,

I have a MOBI calculus book which I need to edit. I use Calibre and have converted it to all formats I could possibly edit (HTML, TXT, PDF, RTF, ePub).

The book contains a lot of formulas which after the conversion come out as a magenta square with text in black. At least in the HTML file they are converted to Jpg, and I guess the same happens in RTF conversion.

How can I convert and have white background with black text?

Alberto Odor, MD

Serpentine · 11-17-2011, 07:57 AM

Export to epub, edit in Sigil.

Just look around for tags that might be giving it the background colour in the CSS.

dwig · 11-17-2011, 08:06 AM

Quote:

Originally Posted by aodor

...
The book contains a lot of formulas which after the conversion come out as a magenta square with text in black. At least in the HTML file they are converted to Jpg, ...

View the JPGs created in the HTML conversion in some viewer independently of the HTML code. Open them directly in your OS's image viewer or, preferable, in Photoshop or similar editor. If they still have the magenta background when viewed this way the only fix is to edit the JPGs in an image editor (e.g. Photoshop, ...) to alter the color and resave.

If using Photoshop you should resave using the special "Save for Web and Devices..." option rather than the standard "Save as..." method. The former creates a more compact file by omitting extra data that is not needed for ebook use.

aodor · 11-17-2011, 12:20 PM

Yes, they are magenta in Photoshop or any other imaging app. Resolution is low, so modifying the images in photoshop makes them unreadable.

dwig · 11-17-2011, 12:39 PM

Quote:

Originally Posted by aodor

...Resolution is low, so modifying the images in photoshop makes them unreadable.

Sounds odd. I've never had difficulty altering even low resolution files in PS and loosing readability. In fact, I often can improve the image.

aodor · 11-17-2011, 01:05 PM

I would include one of them for you to see, but I don't think we can place attachments here.

itimpi · 11-17-2011, 01:20 PM

You can add attachements as long as they are not copyrighted.

aodor · 11-17-2011, 01:31 PM

Yes, here are some of them.

aodor · 11-17-2011, 01:31 PM

As you can see some of them converted with white background, but 95% of them are magenta

theducks · 11-17-2011, 01:46 PM

Are these from the Original? Or after Calibre conversion?

The magenta ones appear to be of poor quality (scans?) when viewed in Paintshop pro and the color replacer did not do well with all the artifacts.

Serpentine · 11-17-2011, 01:54 PM

Ah my bad, those are images. Looks like a problem with the image lib, might want to try using mobiunpack and see if they are output correctly.

dwig · 11-17-2011, 02:28 PM

Yup, something nasty happened during conversion. The images in the MOBI that acquire the magenta background probably have some attribute (e.g. extra alpha channel layer, ...) that calibre's image.lib fails to recognize and properly handle. Massaging these in PS can yield decent images (see attached before & after example), at least no worse than the exported images, but there are so many JPEG compression artifacts that they still aren't very good.

JSWolf · 11-17-2011, 02:30 PM

Quote:

Originally Posted by Serpentine

Ah my bad, those are images. Looks like a problem with the image lib, might want to try using mobiunpack and see if they are output correctly.

I agree to use Mobiunpack and get the images out untouched. Then you can use PS to fix the problem with them.

aodor · 11-17-2011, 03:44 PM

They are from a Clibre converted MOBI file.
I'll give Mobiunpak a try.

Thanks.

aodor · 11-17-2011, 05:58 PM

YES!
Mobiunpack did the trick. All formulas unpacked look good. So, the problem was the Calibre translation.

Thanks you all for your help.

Alberto

11-16-2011, 11:52 AM	#1
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	MOBI > anything = formulas get magenta background Hi, I have a MOBI calculus book which I need to edit. I use Calibre and have converted it to all formats I could possibly edit (HTML, TXT, PDF, RTF, ePub). The book contains a lot of formulas which after the conversion come out as a magenta square with text in black. At least in the HTML file they are converted to Jpg, and I guess the same happens in RTF conversion. How can I convert and have white background with black text? Alberto Odor, MD

11-17-2011, 01:31 PM	#8
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	Yes, here are some of them. Attached Thumbnails Attached Images

11-17-2011, 02:28 PM	#12
dwig Wizard Posts: 1,613 Karma: 6718541 Join Date: Dec 2004 Location: Paradise (Key West, FL) Device: Current:Surface Go & Kindle 3 - Retired: DellV8p, Clie UX50, ...	Yup, something nasty happened during conversion. The images in the MOBI that acquire the magenta background probably have some attribute (e.g. extra alpha channel layer, ...) that calibre's image.lib fails to recognize and properly handle. Massaging these in PS can yield decent images (see attached before & after example), at least no worse than the exported images, but there are so many JPEG compression artifacts that they still aren't very good. Attached Thumbnails

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11-17-2011, 07:57 AM	#2
Serpentine Evangelist Posts: 416 Karma: 1045911 Join Date: Sep 2011 Location: Cape Town, South Africa Device: Kindle 3	Export to epub, edit in Sigil. Just look around for tags that might be giving it the background colour in the CSS.

11-17-2011, 12:20 PM	#4
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	Yes, they are magenta in Photoshop or any other imaging app. Resolution is low, so modifying the images in photoshop makes them unreadable.

11-17-2011, 01:05 PM	#6
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	I would include one of them for you to see, but I don't think we can place attachments here.

11-17-2011, 01:20 PM	#7
itimpi Wizard Posts: 4,553 Karma: 950151 Join Date: Nov 2008 Device: Sony PRS-950, iphone/ipad (Marvin/iBooks/QuickReader)	You can add attachements as long as they are not copyrighted.

11-17-2011, 01:46 PM	#10
theducks Well trained by Cats Posts: 31,054 Karma: 60358908 Join Date: Aug 2009 Location: The Central Coast of California Device: Kobo Libra2,Kobo Aura2v1, K4NT(Fixed: New Bat.), Galaxy Tab A	Are these from the Original? Or after Calibre conversion? The magenta ones appear to be of poor quality (scans?) when viewed in Paintshop pro and the color replacer did not do well with all the artifacts.

11-17-2011, 01:54 PM	#11
Serpentine Evangelist Posts: 416 Karma: 1045911 Join Date: Sep 2011 Location: Cape Town, South Africa Device: Kindle 3	Ah my bad, those are images. Looks like a problem with the image lib, might want to try using mobiunpack and see if they are output correctly.

11-17-2011, 03:44 PM	#14
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	They are from a Clibre converted MOBI file. I'll give Mobiunpak a try. Thanks.

11-17-2011, 05:58 PM	#15
aodor Member Posts: 15 Karma: 10 Join Date: Apr 2011 Device: Kobo	YES! Mobiunpack did the trick. All formulas unpacked look good. So, the problem was the Calibre translation. Thanks you all for your help. Alberto

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