The first one is GRAPE software by POP3DART developed based on the book Lenticular Imaging written by Yitzhak Weissman. GRAPE is a free interlacer application / software for producing interlaced images for printing lenticular images.
The latest version is completely free without any limitations and was released on January 2021 under GNU general public license ver. 3 (GPL 3). As far as I have researched, this is the latest and best freeware lenticular software available under GPL license.