diff --git a/src/blitter/32bpp_simple.cpp b/src/blitter/32bpp_simple.cpp
index fa6155d742..3a80fe9911 100644
--- a/src/blitter/32bpp_simple.cpp
+++ b/src/blitter/32bpp_simple.cpp
@@ -122,7 +122,7 @@ Sprite *Blitter_32bppSimple::Encode(SpriteLoader::Sprite *sprite, AllocatorProc
 			dst[i].v = rgb_max;
 
 			/* Pre-convert the mapping channel to a RGB value */
-			uint colour = this->AdjustBrightness(this->LookupColourInPalette(src[i].m), dst[i].v);
+			uint colour = this->AdjustBrightness(this->LookupColourInPalette(src->m), dst[i].v);
 			dst[i].r = GB(colour, 16, 8);
 			dst[i].g = GB(colour, 8,  8);
 			dst[i].b = GB(colour, 0,  8);