How to choose sl picture format

Hello, I copied the image to the project, how should I make SL generate the image format I want, for example, generate LV_IMG_CF_TRUE_COLOR_ALPHA, it seems that the default is LV_IMG_CF_TRUE_COLOR. Thank you for the reply!

SLS checks all the pixels of an image and is there is at least one pixel with not 0xFF alpha it will use LV_IMG_CF_TRUE_COLOR_ALPHA else LV_IMG_CF_TRUE_COLOR.