How to paint this Captcha?

[player]

Hello, i wonder how Capmonster recognizes a Captcha. Is Capmonster searching for light or dark spots on an image?

I have this Captcha:



You can see there are a lot of contrasts. Should i paint only the dark red spots or everything that is not white? Or what is the best way?

 

[player]

Ah, i see the original looks different. There is mainly red and white. The original is a .gif and this is a .jpg.

How can i convert it to .jpg without data loss? Or will Capmonster be able to work with gif's in the future?

 

[Hungry Bulldozer]

You should paint all the red spots making it looks like a character, don't paint separated points.
CapMonster will support other formats in the future versions.