RGB to grayscale using YUV

I have a bitmap file. I have to convert it in gray scale using YUV color model. Can any one help me?Please hurry assignment due within 3 hours

Try this

First convert YUV into RGB using these formulae

R = Y + V
G = Y - 0.166667U - 0.5V
B = Y + U

Then calculate Gray scale from this by using this formula

GrayLevel = R * 0.30 + G * 0.59 + B * 0.11

Hope it helps.