remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap
remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap
remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap
remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap
code refine
add device_attribute (not implemented, same as identify/DECID), add comment
remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap
remove unused code, rename struct {sixel_canvas_t, cell_t} bitmap -> pixmap