gdi.c: the GDI codec can now open and save BMP files.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@2840 92316355-f0b4-4df1-b90c-862c8a59935f

pipi/Makefile.am

@@ -103,6 +103,7 @@ codec_sources += codec/opencv.c
 endif
 
 if USE_GDI
+codec_libs += -lgdi32
 codec_sources += codec/gdi.c
 endif
 

pipi/codec.c

@@ -48,6 +48,10 @@ pipi_image_t *pipi_load(char const *name)
     if(!ret)
         ret = pipi_load_sdl(name);
 #endif
+#if USE_GDI
+    if(!ret)
+        ret = pipi_load_gdi(name);
+#endif
 
     return ret;
 }
@@ -82,6 +86,10 @@ int pipi_save(pipi_image_t *img, const char *name)
     if(ret < 0)
         ret = pipi_save_sdl(img, name);
 #endif
+#if USE_GDI
+    if(ret < 0)
+        ret = pipi_save_gdi(img, name);
+#endif
 
     return ret;
 }

pipi/codec/gdi.c

@@ -0,0 +1,153 @@
+/*
+ *  libpipi       Proper image processing implementation library
+ *  Copyright (c) 2004-2008 Sam Hocevar <sam@zoy.org>
+ *                All Rights Reserved
+ *
+ *  $Id$
+ *
+ *  This library is free software. It comes without any warranty, to
+ *  the extent permitted by applicable law. You can redistribute it
+ *  and/or modify it under the terms of the Do What The Fuck You Want
+ *  To Public License, Version 2, as published by Sam Hocevar. See
+ *  http://sam.zoy.org/wtfpl/COPYING for more details.
+ */
+
+/*
+ * gdi.c: Windows GDI I/O functions (BMP only)
+ */
+
+#include "config.h"
+#include "common.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <windows.h>
+
+#include "pipi.h"
+#include "pipi_internals.h"
+
+pipi_image_t *pipi_load_gdi(const char *name)
+{
+    BITMAPINFO binfo;
+    pipi_image_t *img;
+    pipi_pixels_t *p;
+    uint8_t *data;
+    HBITMAP hbmap;
+    HDC hdc;
+    int x, y;
+
+    hbmap = (HBITMAP)LoadImage(NULL, name, IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
+    if(!hbmap)
+        return NULL;
+
+    hdc = CreateCompatibleDC(NULL);
+    SelectObject(hdc, hbmap);
+
+    memset(&binfo, 0, sizeof(binfo));
+    binfo.bmiHeader.biSize = sizeof(binfo.bmiHeader);
+    if(!GetDIBits(hdc, hbmap, 0, 0, 0, &binfo, DIB_RGB_COLORS))
+    {
+        ReleaseDC(0, hdc);
+        DeleteObject(hbmap);
+        return NULL;
+    }
+
+    img = pipi_new(binfo.bmiHeader.biWidth, binfo.bmiHeader.biHeight);
+    p = pipi_getpixels(img, PIPI_PIXELS_RGBA_C);
+    data = p->pixels;
+
+    binfo.bmiHeader.biBitCount = 32;
+    binfo.bmiHeader.biCompression = BI_RGB;
+    binfo.bmiHeader.biHeight = - abs(binfo.bmiHeader.biHeight);
+    if(!GetDIBits(hdc, hbmap, 0, binfo.bmiHeader.biHeight, data,
+                  &binfo, DIB_RGB_COLORS))
+    {
+        ReleaseDC(0, hdc);
+        DeleteObject(hbmap);
+        return NULL;
+    }
+
+    /* FIXME: get rid of this loop, maybe by using BITMAPV4HEADER above
+     * so that GDI reorders the pixels for us. */
+    for(y = 0; y < img->h; y++)
+        for(x = 0; x < img->w; x++)
+        {
+            /* Swap B and R, don't touch G and A. */
+            uint8_t tmp = data[0]; data[0] = data[2]; data[2] = tmp;
+            data += 4;
+        }
+
+    img->codec_priv = NULL;
+
+    img->wrap = 0;
+    img->u8 = 1;
+
+    ReleaseDC(0, hdc);
+    DeleteObject(hbmap);
+
+    return img;
+}
+
+int pipi_save_gdi(pipi_image_t *img, const char *name)
+{
+    BITMAPINFOHEADER binfo;
+    BITMAPFILEHEADER bfheader;
+    uint8_t dummy[4] = { 0 };
+    HANDLE hfile;
+    pipi_pixels_t *p;
+    DWORD ret = 0;
+    uint8_t *data;
+    int x, y, padding;
+
+    p = pipi_getpixels(img, PIPI_PIXELS_RGBA_C);
+    data = p->pixels;
+
+    padding = ((img->w * 3) + 3) / 4 * 4 - img->w * 3;
+
+    memset(&binfo, 0, sizeof(binfo));
+    binfo.biSize = sizeof(binfo);
+    binfo.biWidth = img->w;
+    binfo.biHeight = img->h;
+    binfo.biPlanes = 1;
+    binfo.biBitCount = 24;
+    binfo.biCompression = BI_RGB;
+    binfo.biSizeImage = (img->w * 3 + padding) * img->h;
+
+    memset(&bfheader, 0, sizeof(bfheader));
+    bfheader.bfType = 0x4D42;
+    bfheader.bfOffBits = sizeof(bfheader) + sizeof(binfo);
+    bfheader.bfSize = bfheader.bfOffBits + binfo.biSizeImage;
+
+    /* We don’t even create the bitmap object, since we know exactly
+     * what kind of file we are saving. But later, when we support
+     * different depths and BMP options, we'll need to care about it. */
+    hfile = CreateFile(name, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,
+                       FILE_ATTRIBUTE_ARCHIVE, NULL);
+    if(!hfile)
+        return -1;
+    WriteFile(hfile, &bfheader, sizeof(bfheader), &ret, NULL);
+    WriteFile(hfile, &binfo, sizeof(binfo), &ret, NULL);
+    for(y = 0; y < img->h; y++)
+    {
+        for(x = 0; x < img->w; x++)
+        {
+            uint8_t tmp[3];
+            tmp[0] = data[4 * (img->w * (img->h - 1 - y) + x) + 2];
+            tmp[1] = data[4 * (img->w * (img->h - 1 - y) + x) + 1];
+            tmp[2] = data[4 * (img->w * (img->h - 1 - y) + x) + 0];
+            WriteFile(hfile, tmp, 3, &ret, NULL);
+        }
+        if(padding)
+            WriteFile(hfile, dummy, padding, &ret, NULL);
+    }
+    CloseHandle(hfile);
+
+    return 0;
+}
+
+/*
+ * XXX: The following functions are local.
+ */
+

pipi/pipi_internals.h

@@ -80,5 +80,10 @@ pipi_image_t *pipi_load_sdl(const char *name);
 int pipi_save_sdl(pipi_image_t *img, const char *name);
 #endif
 
+#ifdef USE_GDI
+pipi_image_t *pipi_load_gdi(const char *name);
+int pipi_save_gdi(pipi_image_t *img, const char *name);
+#endif
+
 #endif /* __PIPI_INTERNALS_H__ */