2 files changed, 29 insertions, 4 deletions
diff --git a/tools/gbagfx/gfx.c b/tools/gbagfx/gfx.c
index c09c4238e..c0f7f492c 100644
--- a/tools/gbagfx/gfx.c
+++ b/tools/gbagfx/gfx.c
@@ -292,10 +292,10 @@ void ReadGbaPalette(char *path, struct Palette *palette)
 	int fileSize;
 	unsigned char *data = ReadWholeFile(path, &fileSize);
 
-	palette->numColors = fileSize / 2;
+	if (fileSize % 2 != 0)
+		FATAL_ERROR("The file size (%d) is not a multiple of 2.\n", fileSize);
 
-	if (palette->numColors != 16 && palette->numColors != 256)
-		FATAL_ERROR("\"%s\" contains %d colors, but the number of colors must be 16 or 256.\n", path, palette->numColors);
+	palette->numColors = fileSize / 2;
 
 	for (int i = 0; i < palette->numColors; i++) {
 		uint16_t paletteEntry = (data[i * 2 + 1] << 8) | data[i * 2];
diff --git a/tools/gbagfx/main.c b/tools/gbagfx/main.c
index 56a1c2c7b..cc1e8f807 100644
--- a/tools/gbagfx/main.c
+++ b/tools/gbagfx/main.c
@@ -129,11 +129,36 @@ void HandleGbaToJascPaletteCommand(char *inputPath, char *outputPath, int argc U
 	WriteJascPalette(outputPath, &palette);
 }
 
-void HandleJascToGbaPaletteCommand(char *inputPath, char *outputPath, int argc UNUSED, char **argv UNUSED)
+void HandleJascToGbaPaletteCommand(char *inputPath, char *outputPath, int argc, char **argv)
 {
+	int numColors = 0;
+
+	for (int i = 3; i < argc; i++) {
+		char *option = argv[i];
+
+		if (strcmp(option, "-num_colors") == 0) {
+			if (i + 1 >= argc)
+				FATAL_ERROR("No number of colors following \"-num_colors\".\n");
+
+			i++;
+
+			if (!ParseNumber(argv[i], NULL, 10, &numColors))
+				FATAL_ERROR("Failed to parse number of colors.\n");
+
+			if (numColors < 1)
+				FATAL_ERROR("Number of colors must be positive.\n");
+		} else {
+			FATAL_ERROR("Unrecognized option \"%s\".\n", option);
+		}
+	}
+
 	struct Palette palette;
 
 	ReadJascPalette(inputPath, &palette);
+
+	if (numColors != 0)
+		palette.numColors = numColors;
+
 	WriteGbaPalette(outputPath, &palette);
 }