From dc13a6ae95fda976e6719fe55be7f4baa877cd2b Mon Sep 17 00:00:00 2001
From: John Kvalevog <[EMAIL REDACTED]>
Date: Sat, 1 Feb 2025 11:13:47 -0600
Subject: [PATCH] SDL_SaveBMP_IO: Write bitmap header v5 values
bV4CSType was changed to LCS_sRGB to work with Preview on macOS.
Fixes: #11903
---
src/video/SDL_bmp.c | 40 ++++++++++++++++++++++++++++++++++++----
1 file changed, 36 insertions(+), 4 deletions(-)
diff --git a/src/video/SDL_bmp.c b/src/video/SDL_bmp.c
index d8b1c9dbba63c..bcde0c5786e02 100644
--- a/src/video/SDL_bmp.c
+++ b/src/video/SDL_bmp.c
@@ -46,11 +46,23 @@
#endif
// Logical color space values for BMP files
+// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-wmf/eb4bbd50-b3ce-4917-895c-be31f214797f
#ifndef LCS_WINDOWS_COLOR_SPACE
// 0x57696E20 == "Win "
#define LCS_WINDOWS_COLOR_SPACE 0x57696E20
#endif
+#ifndef LCS_sRGB
+// 0x73524742 == "sRGB"
+#define LCS_sRGB 0x73524742
+#endif
+
+// Logical/physical color relationship
+// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-wmf/9fec0834-607d-427d-abd5-ab240fb0db38
+#ifndef LCS_GM_GRAPHICS
+#define LCS_GM_GRAPHICS 0x00000002
+#endif
+
static bool readRlePixels(SDL_Surface *surface, SDL_IOStream *src, int isRle8)
{
/*
@@ -637,6 +649,12 @@ bool SDL_SaveBMP_IO(SDL_Surface *surface, SDL_IOStream *dst, bool closeio)
Uint32 bV4GammaGreen = 0;
Uint32 bV4GammaBlue = 0;
+ // The additional header members from the Win32 BITMAPV5HEADER struct (124 bytes in total)
+ Uint32 bV5Intent = 0;
+ Uint32 bV5ProfileData = 0;
+ Uint32 bV5ProfileSize = 0;
+ Uint32 bV5Reserved = 0;
+
// Make sure we have somewhere to save
if (!SDL_SurfaceValid(surface)) {
SDL_InvalidParamError("surface");
@@ -728,19 +746,25 @@ bool SDL_SaveBMP_IO(SDL_Surface *surface, SDL_IOStream *dst, bool closeio)
}
biClrImportant = 0;
- // Set the BMP info values for the version 4 header
+ // Set the BMP info values
if (save32bit && !saveLegacyBMP) {
- biSize = 108;
+ biSize = 124;
+ // Version 4 values
biCompression = BI_BITFIELDS;
// The BMP format is always little endian, these masks stay the same
bV4RedMask = 0x00ff0000;
bV4GreenMask = 0x0000ff00;
bV4BlueMask = 0x000000ff;
bV4AlphaMask = 0xff000000;
- bV4CSType = LCS_WINDOWS_COLOR_SPACE;
+ bV4CSType = LCS_sRGB;
bV4GammaRed = 0;
bV4GammaGreen = 0;
bV4GammaBlue = 0;
+ // Version 5 values
+ bV5Intent = LCS_GM_GRAPHICS;
+ bV5ProfileData = 0;
+ bV5ProfileSize = 0;
+ bV5Reserved = 0;
}
// Write the BMP info values
@@ -758,8 +782,9 @@ bool SDL_SaveBMP_IO(SDL_Surface *surface, SDL_IOStream *dst, bool closeio)
goto done;
}
- // Write the BMP info values for the version 4 header
+ // Write the BMP info values
if (save32bit && !saveLegacyBMP) {
+ // Version 4 values
if (!SDL_WriteU32LE(dst, bV4RedMask) ||
!SDL_WriteU32LE(dst, bV4GreenMask) ||
!SDL_WriteU32LE(dst, bV4BlueMask) ||
@@ -777,6 +802,13 @@ bool SDL_SaveBMP_IO(SDL_Surface *surface, SDL_IOStream *dst, bool closeio)
!SDL_WriteU32LE(dst, bV4GammaBlue)) {
goto done;
}
+ // Version 5 values
+ if (!SDL_WriteU32LE(dst, bV5Intent) ||
+ !SDL_WriteU32LE(dst, bV5ProfileData) ||
+ !SDL_WriteU32LE(dst, bV5ProfileSize) ||
+ !SDL_WriteU32LE(dst, bV5Reserved)) {
+ goto done;
+ }
}
// Write the palette (in BGR color order)