diff --git a/coders/bmp.c b/coders/bmp.c
index 6b31d60..cf61a30 100644
--- a/coders/bmp.c
+++ b/coders/bmp.c
@@ -840,9 +840,9 @@
image->columns=(size_t) MagickAbsoluteValue(bmp_info.width);
image->rows=(size_t) MagickAbsoluteValue(bmp_info.height);
image->depth=bmp_info.bits_per_pixel <= 8 ? bmp_info.bits_per_pixel : 8;
- if ((bmp_info.bits_per_pixel == 16) || (bmp_info.bits_per_pixel == 32))
- image->alpha_trait=bmp_info.alpha_mask != 0 ? BlendPixelTrait :
- UndefinedPixelTrait;
+ image->alpha_trait=(bmp_info.alpha_mask != 0) ||
+ ((bmp_info.compression == BI_RGB) && (bmp_info.bits_per_pixel == 32)) ?
+ BlendPixelTrait : UndefinedPixelTrait;
if ((bmp_info.number_colors != 0) || (bmp_info.bits_per_pixel < 16))
{
size_t
@@ -947,7 +947,8 @@
*/
if (bmp_info.compression == BI_RGB)
{
- bmp_info.alpha_mask=0;
+ bmp_info.alpha_mask=image->alpha_trait == BlendPixelTrait ?
+ 0xff000000L : 0L;
bmp_info.red_mask=0x00ff0000U;
bmp_info.green_mask=0x0000ff00U;
bmp_info.blue_mask=0x000000ffU;