Table 1. Structure of colorization model

Type	Kernel	Stride	Outputs
Conv.	3 x 3	2 x 2	4
Conv.	3 x 3	1 x 1	8
Conv.	3 x 3	2 x 2	8
Conv.	3 x 3	1 x 1	16
Conv.	3 x 3	2 x 2	16
Conv.	3 x 3	1 x 1	32
Conv.	3 x 3	2 x 2	32
Conv.	3 x 3	1 x 1	32
Conv.	3 x 3	2 x 2	64
Conv.	3 x 3	1 x 1	128
DeConv.	3 x 3	1/2 x 1/2	128
Conv.	3 x 3	1 x 1	64
DeConv.	3 x 3	1/2 x 1/2	64
Conv.	3 x 3	1 x 1	32
DeConv.	3 x 3	1/2 x 1/2	32
Conv.	3 x 3	1 x 1	16
DeConv.	3 x 3	1/2 x 1/2	16
Conv.	3 x 3	1 x 1	8
DeConv.	3 x 3	1/2 x 1/2	8
Conv.	3 x 3	1 x 1	2