Multiples Colors as Transparent Color

How-to
1

Description

The problem is that i have some images in bitmap format with a custom transparency color. After image conversion with TRUE_COLAR_CHROMA_KEY for a .bin file some images still show this color in the display. The problem is not in lvgl image converter, probrably it is the image itself (i get the images from my client), because i already have this same problem with other lib and with other image converter tool. I solved this in this other lib using more than one color as transparency. I could not found a way to this with LVGL. Can i do the same in LVGL?

What MCU/Processor/Board and compiler are you using?

MCU: TM4C1294 Cortex M4
Compiler: TI ARM CGT 19

What LVGL version are you using?

7.11

What do you want to achieve?

Use multiples colors as a LV_COLOR_TRANSP.

Finally, Thanks for this great work. LVGL is one of the best graphics lib i used for embedded development (Awesome docs, code and community. Also free!). You have all my love!

2

LVGL only supports one chroma-key color, but here’s a possible workaround if it’s just a few images: open the image in GIMP and use the select color tool to replace the colors which should be chromakeyed with LV_COLOR_CHROMA_KEY. Converting the resulting image should work the way you want.

3

GIMP solved my issue. Many thanks! Just for remark. I think the problem is in the conversion of bitmap images. I don´t know the reason, but sometimes conversion do not work correctly with bitmap. Using the same image as PNG, also solved the problem.

4

hello, I need support to display with tm4c1294 with lvgl library please send me any reference code with that controller tm4c1294.