Create a negative art with a ballpoint pen drawing using Android's "Gallery" application.

I'm not good at English. So I am using machine translation.
If you find strange English, I would be happy if you point out in comments.

1. Original image and completed image

(1) Original image

(2) Completed image

2. Tutorial

(1) Launch "Gallery" of Android application.

(2) Simply negative / positive inversion will result in black and white inversion + hue of 180 degrees.

(3) Therefore, when only the hue is returned by 180 degrees, only the black and white inversion is performed with the hue remaining the original.

(4) Further, in that state, adjust the color to be tasteful.
Filter processing, lower highlight, Red only saturation etc.

It looks like I painted on the blackboard.

thank you for reading it until the very end.
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