MobileRead Forums - View Single Post - How to turn all images in Kobo Forma to grayscale (to save space & speed xp)

droopy · 10-17-2019, 02:40 AM

I made a backup of this big book.

The original book, as measured inside Calibre's library view, is 443.7MB.
After I opened the book editor and chose Tools>Compress_Images_Losslessly (I kept "Enable lossy compression of JPEG images" unticked/unchecked), the book became 417.9 MB.
That's a difference of 25.8 MB, or a savings of 5.8%.

10-17-2019, 02:40 AM	#17
droopy Guru Posts: 834 Karma: 2912460 Join Date: Apr 2009 Device: Kobo Forma	I made a backup of this big book. The original book, as measured inside Calibre's library view, is 443.7MB. After I opened the book editor and chose Tools>Compress_Images_Losslessly (I kept "Enable lossy compression of JPEG images" unticked/unchecked), the book became 417.9 MB. That's a difference of 25.8 MB, or a savings of 5.8%.