This is not bootanimation, this is the splash screen (the Mi' boot logo which is displayed when device is switched ON)
This is for Redmi 4A/4 Only..
For other devices, please send me your splash.img so that I can create a tool for you too.
1. Rooted Redmi 4A/4 (any ROM)
2. Terminal Emulator app
STEPS to create & flash splash.img:
Same procedure as in here:
[GUIDE] How to Create Custom Splash Screen (Boot Logo) for Redmi 2/3
Hit the Thanks button if it worked for you
You're welcome to post the splash images that you created..
Thanks to @karantamboli who provided stock splash.img of Redmi 4A..