fix(#6): use libraw_set_saturation_mul instead of libraw_set_gamma for saturation

src/main.rs

@@ -335,10 +335,11 @@ fn apply_image_parameters(lr: *mut libraw_data_t, args: &Args) {
             libraw_set_use_auto_wb(lr, 0);
         }
 
-        // Apply saturation
+        // Apply saturation (use saturation multiplier, not gamma)
         if args.saturation != 0 && !lr.is_null() {
-            let value = 1.0 + args.saturation.min(100).max(-100) as f32 / 100.0;
-            libraw_set_gamma(lr, 0, value); // Apply gamma adjustment to simulate saturation
+            let mul = (256i32 + args.saturation.min(100).max(-100) as i32 * 2) as c_int;
+            let sat_mul = [mul, mul, mul, mul];
+            libraw_set_saturation_mul(lr, sat_mul.as_ptr());
         }
 
         // Set output color space (sRGB in this case)