Moto g boot animation

Hey guys.....I have a moto g xt1033 and lollipop 5.1 stock Motorola rom .....rooted! Whenever I copy a bootanimation.zip to system/media which has the bootanimation in the form of a mp4 and reboot....only a bootloader warning is displayed instead of the video and the phone boots up....however in the case of animation consisting of image files,it works fine....any help about that..or if u could help me set 2-3 videos as the bootanimation...

Sent from my XT1033 using XDA Free mobile app