Creates a new pixbuf which represents a sub-region of @src_pixbuf.
The new pixbuf shares its pixels with the original pixbuf, so
writing to one affects both. The new pixbuf holds a reference to
@src_pixbuf, so @src_pixbuf will not be finalized until the new
pixbuf is finalized.
Note that if @src_pixbuf is read-only, this function will force it
to be mutable.
Creates a new pixbuf which represents a sub-region of @src_pixbuf. The new pixbuf shares its pixels with the original pixbuf, so writing to one affects both. The new pixbuf holds a reference to @src_pixbuf, so @src_pixbuf will not be finalized until the new pixbuf is finalized.
Note that if @src_pixbuf is read-only, this function will force it to be mutable.