diff --git a/bin/main.c b/bin/main.c
index 3f51a20..da1191b 100644
--- a/bin/main.c
+++ b/bin/main.c
@@ -37,8 +37,8 @@ static void usage(int argc, char **argv, const char *message, ...) {
     fprintf(stderr, "usage: %1$s import       file.sav 1..30 input.png\n"
                     "       %1$s export       file.sav 1..30 output.png\n"
                     "       %1$s dither       input.png output.png\n"
-                    "       %1$s split        file.sav rn gn bn input.png\n"
-                    "       %1$s merge        file.sav rn gn bn output.png\n"
+                    "       %1$s split-rgb    file.sav rn gn bn input.png\n"
+                    "       %1$s merge-rgb    file.sav rn gn bn output.png\n"
                     "       %1$s import-tile  file.sav 1..30 printer.tile\n"
                     "       %1$s export-tile  file.sav 1..30 output.tile\n"
                     "       %1$s convert-tile printer.tile output.png\n",
@@ -328,7 +328,7 @@ static void validate_photo_number(int argc, char **argv, int num) {
     }
 }
 
-static int split(int argc, char **argv) {
+static int split_rgb(int argc, char **argv) {
     cammy_sram *sram;
     png_t *png;
 
@@ -429,7 +429,7 @@ error_sram_open:
     return 1;
 }
 
-static int merge(int argc, char **argv) {
+static int merge_rgb(int argc, char **argv) {
     cammy_sram *sram;
     png_t *png;
 
@@ -742,8 +742,8 @@ static struct {
     { "import",       import       },
     { "export",       export       },
     { "dither",       dither       },
-    { "split",        split        },
-    { "merge",        merge        },
+    { "split-rgb",    split_rgb    },
+    { "merge-rgb",    merge_rgb    },
     { "import-tile",  import_tile  },
     { "export-tile",  export_tile  },
     { "convert-tile", convert_tile },
diff --git a/src/image.c b/src/image.c
index 16f625b..fd181a4 100644
--- a/src/image.c
+++ b/src/image.c
@@ -73,7 +73,7 @@ static uint32_t bayer_matrix[256] = {
 };
 
 static uint8_t level_2bpp_to_8bpp[4] = {
-    0, 85, 171, 255
+    0, 87, 171, 255
 };
 
 static uint8_t rgb_to_grayscale(uint8_t r, uint8_t g, uint8_t b) {