MobileRead Forums - View Single Post - PNG Images in ePUB Files not rendered on Kobo

DragonflyKing · 10-11-2013, 05:12 AM

I have created my book in Sigil which uses many black and white images (line art style - scans of simple etched or vinyl cut prints). The PNG images display fine in Sigil and Calibre but are blank (white space) when downloaded to my Kobo Touch.

The KT is supposed to support PNG files, so I was wondering why it cannot render the images. The book has a few JPGs and they show fine in the KT.

The PNG files were created in Corel Paint Shop Pro X2 using a greyscale pallet and saved as PNG Non-Interlaced with Optimised Pallet.

I would like to keep the images in PNG format as a typical 17KB PNG image becomes a nasty 132KB when saved as JPG. I could reduce the JPG quality but I have to use a 90% compression factor to get the same size file while the image looks muddy and awful. As most images are a large white expanse with crisp black lines, I want to preserve this as much as possible.

Has anyone experienced this or could anyone suggest a solution? I don't know if it is limited to the Kobo.

Many Thanks.

10-11-2013, 05:12 AM	#1
DragonflyKing Enthusiast Posts: 28 Karma: 9040 Join Date: Mar 2012 Device: Kobo Touch	PNG Images in ePUB Files not rendered on Kobo I have created my book in Sigil which uses many black and white images (line art style - scans of simple etched or vinyl cut prints). The PNG images display fine in Sigil and Calibre but are blank (white space) when downloaded to my Kobo Touch. The KT is supposed to support PNG files, so I was wondering why it cannot render the images. The book has a few JPGs and they show fine in the KT. The PNG files were created in Corel Paint Shop Pro X2 using a greyscale pallet and saved as PNG Non-Interlaced with Optimised Pallet. I would like to keep the images in PNG format as a typical 17KB PNG image becomes a nasty 132KB when saved as JPG. I could reduce the JPG quality but I have to use a 90% compression factor to get the same size file while the image looks muddy and awful. As most images are a large white expanse with crisp black lines, I want to preserve this as much as possible. Has anyone experienced this or could anyone suggest a solution? I don't know if it is limited to the Kobo. Many Thanks.