is a 9 byte 1 × 1 pixel black image in portable bitmap format (https://en.wikipedia.org/wiki/Netpbm#File_formats). Consumers of such files likely will know how to scale them to 256 × 256 pixels. The trailing newline may not even be necessary. If so, it would become 8 bytes.
Gray 1 X 1 pixel images in binary portable graymap format have the same size. To get a non-gray RGB color, you’ll need two more bytes in binary portable pixmap format.
Gray 1 X 1 pixel images in binary portable graymap format have the same size. To get a non-gray RGB color, you’ll need two more bytes in binary portable pixmap format.