diff --git a/test-zrle.c b/test-zrle.c
new file mode 100644
index 0000000..3c0214d
--- /dev/null
+++ b/test-zrle.c
@@ -0,0 +1,168 @@
+#include "zrle.h"
+#include "rfb-proto.h"
+
+#include <endian.h>
+#include <stdio.h>
+
+int test_pixel32_to_cpixel_3(void)
+{
+	static uint32_t src[64] = { 0 };
+	static uint8_t dst[64 * 3] = { 0 };
+
+	struct rfb_pixel_format srcfmt = { 0 }, dstfmt = { 0 };
+
+	srcfmt.depth = 24;
+	srcfmt.bits_per_pixel = 32;
+	srcfmt.true_colour_flag = 1;
+	srcfmt.red_max = 255;
+	srcfmt.green_max = 255;
+	srcfmt.blue_max = 255;
+	srcfmt.red_shift = 24;
+	srcfmt.green_shift = 16;
+	srcfmt.blue_shift = 8;
+
+	dstfmt.depth = 24;
+	dstfmt.bits_per_pixel = 32;
+	dstfmt.true_colour_flag = 1;
+	dstfmt.red_max = 255;
+	dstfmt.green_max = 255;
+	dstfmt.blue_max = 255;
+	dstfmt.red_shift = 8;
+	dstfmt.green_shift = 16;
+	dstfmt.blue_shift = 24;
+
+	for (int i = 0; i < 64; ++i)
+		src[i] = 0x12345678;
+
+	pixel32_to_cpixel(dst, &dstfmt, src, &srcfmt, 3, 64);
+
+	for (int i = 0; i < 64; ++i) {
+		uint8_t r, g, b;
+
+		r = dst[i * 3 + 0];
+		g = dst[i * 3 + 1];
+		b = dst[i * 3 + 2];
+
+		if (r != 0x12 || g != 0x34 || b != 0x56) {
+			printf("pixel32_to_cpixel_3 failed\n");
+			return 1;
+		}
+	}
+
+	printf("pixel32_to_cpixel_3 ran OK\n");
+	return 0;
+}
+
+int test_pixel32_to_cpixel_2(void)
+{
+	static uint32_t src[64] = { 0 };
+	static uint16_t dst[64] = { 0 };
+
+	struct rfb_pixel_format srcfmt = { 0 }, dstfmt = { 0 };
+
+	srcfmt.depth = 24;
+	srcfmt.bits_per_pixel = 32;
+	srcfmt.true_colour_flag = 1;
+	srcfmt.red_max = 255;
+	srcfmt.green_max = 255;
+	srcfmt.blue_max = 255;
+	srcfmt.red_shift = 24;
+	srcfmt.green_shift = 16;
+	srcfmt.blue_shift = 8;
+
+	dstfmt.depth = 16;
+	dstfmt.bits_per_pixel = 16;
+	dstfmt.true_colour_flag = 1;
+	dstfmt.red_max = 31;
+	dstfmt.green_max = 63;
+	dstfmt.blue_max = 31;
+	dstfmt.red_shift = 11;
+	dstfmt.green_shift = 5;
+	dstfmt.blue_shift = 0;
+
+#if __BYTE_ORDER__ == __BIG_ENDIAN__
+	dstfmt.big_endian_flag = 1;
+#endif
+
+	for (int i = 0; i < 64; ++i)
+		src[i] = 0x12345678;
+
+	pixel32_to_cpixel((uint8_t*)dst, &dstfmt, src, &srcfmt, 2, 64);
+
+	for (int i = 0; i < 64; ++i) {
+		uint8_t r, g, b;
+
+		r = (dst[i] >> 11) & 31;
+		g = (dst[i] >> 5) & 63;
+		b = (dst[i] >> 0) & 31;
+
+		if (r != (0x12 >> 3) || g != (0x34 >> 2) || b != (0x56 >> 3)) {
+			printf("pixel32_to_cpixel_2 failed: %x %x %x\n", r, g, b);
+			return 1;
+		}
+	}
+
+	printf("pixel32_to_cpixel_2 ran OK\n");
+	return 0;
+}
+
+int test_pixel32_to_cpixel_1(void)
+{
+	static uint32_t src[64] = { 0 };
+	static uint8_t dst[64] = { 0 };
+
+	struct rfb_pixel_format srcfmt = { 0 }, dstfmt = { 0 };
+
+	srcfmt.depth = 24;
+	srcfmt.bits_per_pixel = 32;
+	srcfmt.true_colour_flag = 1;
+	srcfmt.red_max = 255;
+	srcfmt.green_max = 255;
+	srcfmt.blue_max = 255;
+	srcfmt.red_shift = 24;
+	srcfmt.green_shift = 16;
+	srcfmt.blue_shift = 8;
+
+	dstfmt.depth = 8;
+	dstfmt.bits_per_pixel = 8;
+	dstfmt.true_colour_flag = 1;
+	dstfmt.red_max = 7;
+	dstfmt.green_max = 7;
+	dstfmt.blue_max = 3;
+	dstfmt.red_shift = 5;
+	dstfmt.green_shift = 2;
+	dstfmt.blue_shift = 0;
+
+#if __BYTE_ORDER__ == __BIG_ENDIAN__
+	dstfmt.big_endian_flag = 1;
+#endif
+
+	for (int i = 0; i < 64; ++i)
+		src[i] = 0x98765432;
+
+	pixel32_to_cpixel((uint8_t*)dst, &dstfmt, src, &srcfmt, 1, 64);
+
+	for (int i = 0; i < 64; ++i) {
+		uint8_t r, g, b;
+
+		r = (dst[i] >> 5) & 7;
+		g = (dst[i] >> 2) & 7;
+		b = (dst[i] >> 0) & 3;
+
+		if (r != (0x98 >> 5) || g != (0x76 >> 5) || b != (0x54 >> 6)) {
+			printf("pixel32_to_cpixel_1 failed: %x %x %x\n", r, g, b);
+			return 1;
+		}
+	}
+
+	printf("pixel32_to_cpixel_1 ran OK\n");
+	return 0;
+}
+int main()
+{
+	if (test_pixel32_to_cpixel_3()) return 1;
+	if (test_pixel32_to_cpixel_2()) return 1;
+	if (test_pixel32_to_cpixel_1()) return 1;
+
+	return 0;
+}
diff --git a/zrle.c b/zrle.c
index 6d66fe6..8904abc 100644
--- a/zrle.c
+++ b/zrle.c
@@ -34,6 +34,9 @@ void pixel32_to_cpixel(uint8_t *restrict dst,
 		       const struct rfb_pixel_format* src_fmt,
 		       size_t bytes_per_cpixel, size_t len)
 {
+	assert(src_fmt->true_colour_flag);
+	assert(src_fmt->bits_per_pixel == 32);
+	assert(src_fmt->depth <= 32);
 	assert(dst_fmt->true_colour_flag);
 	assert(dst_fmt->bits_per_pixel <= 32);
 	assert(dst_fmt->depth <= 24);
@@ -79,6 +82,18 @@ void pixel32_to_cpixel(uint8_t *restrict dst,
 
 	switch (bytes_per_cpixel) {
 	case 3:
+		if (dst_fmt->bits_per_pixel == 32 && dst_fmt->depth <= 24) {
+			uint32_t min_dst_shift = dst_red_shift;
+			if (min_dst_shift > dst_green_shift)
+				min_dst_shift = dst_green_shift;
+			if (min_dst_shift > dst_blue_shift)
+				min_dst_shift = dst_blue_shift;
+
+			dst_red_shift -= min_dst_shift;
+			dst_green_shift -= min_dst_shift;
+			dst_blue_shift -= min_dst_shift;
+		}
+
 		dst_endian_correction = dst_fmt->big_endian_flag ? 16 : 0;
 
 		while (len--) {
diff --git a/zrle.h b/zrle.h
new file mode 100644
index 0000000..826db33
--- /dev/null
+++ b/zrle.h
@@ -0,0 +1,15 @@
+#ifndef _ZRLE_H_
+#define _ZRLE_H_
+
+#include <stdint.h>
+#include <unistd.h>
+
+struct rfb_pixel_format;
+
+void pixel32_to_cpixel(uint8_t *restrict dst,
+		       const struct rfb_pixel_format* dst_fmt,
+		       const uint32_t *restrict src,
+		       const struct rfb_pixel_format* src_fmt,
+		       size_t bytes_per_cpixel, size_t len);
+
+#endif /* _ZRLE_H_ */