For most of the people, it is very difficult to remove the background perfectly from a complex image. The hair may be the main problem. Here is a solution in Adobe Photoshop CS5 to remove the complex image background without removing the hair.
Select Quick Selection Tool
Click And Select Photo
Click Refine Edge
Refine Edge Box
Change The view Mode Black & White
Black & White Mode
Take the Refine Radius Tool and click smart radius, change radius.
Just Drag hair edge Only
Select ‘New Layer with Layer Mask , click Ok
Layer Mask Image
Add Background Image.
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