Due to the different RGB/YUV colorspaces and bt601/bt709 conversions at the input and output, we may get some color difference.This is usually a yellow or red tint.

To correct the yellow tint:
ffmpeg -framerate 60 -i %010d.png -c:v libx264 -crf 16 -colorspace smpte170m -color_primaries smpte170m -color_trc smpte170m -pix_fmt yuv420p -y output.mp4

To correct the red hue:
ffmpeg -framerate 60 -i %010d.png -c:v libx264 -crf 16 -colorspace bt709 -color_primaries bt709 -color_trc bt709 -pix_fmt yuv420p -y output.mp4

Rife-app uses ffmpeg to encode the video, then it can be embedded directly into the application.