9. The computer-implemented method for generating a visual feature to semantic space transformation map according to claim 1 , wherein: the proximate relationship is associated with a maximum percentage of a character bounding box overlapping an image block, y d = max ( char_bb i , char_y i ) ∈ C l ⁢ δ i , d ⁢  Intersection ( block_bb , char_bb i )   char_bb i  , where y d represents d dimension of label y, |•| represents an area of an overlapping region, and δ i,d equals 1 if char_y i =Σ d and 0 otherwise.
9. The computer-implemented method for generating a visual feature to semantic space transformation map according to claim 1 , wherein: the proximate relationship is associated with a maximum percentage of a character bounding box overlapping an image block, y d = max ( char_bb i , char_y i ) ∈ C l ⁢ δ i , d ⁢  Intersection ( block_bb , char_bb i )   char_bb i  , where y d represents d dimension of label y, |•| represents an area of an overlapping region, and δ i,d equals 1 if char_y i =Σ d and 0 otherwise. 10. The computer-implemented method for generating a visual feature to semantic space transformation map according to claim 9 , wherein y ^ d , r = max ( char_bb i , char_y i ) ∈ C l ⁢ δ i , d ⁢  Intersection ( block_bb , char_bb i ⁢ ⁢ r )   char_bb i ⁢ ⁢ r  , where r=1 . . . R 2 and char_bb ir denotes the r-th region of character boundary box char_bb.