Data commit

Task/Grayscale-image/C/grayscale-image-1.c

@@ -0,0 +1,12 @@
+typedef unsigned char luminance;
+typedef luminance pixel1[1];
+typedef struct {
+   unsigned int width;
+   unsigned int height;
+   luminance *buf;
+} grayimage_t;
+typedef grayimage_t *grayimage;
+
+grayimage alloc_grayimg(unsigned int, unsigned int);
+grayimage tograyscale(image);
+image tocolor(grayimage);

Task/Grayscale-image/C/grayscale-image-2.c

@@ -0,0 +1,9 @@
+grayimage alloc_grayimg(unsigned int width, unsigned int height)
+{
+     grayimage img;
+     img = malloc(sizeof(grayimage_t));
+     img->buf = malloc(width*height*sizeof(pixel1));
+     img->width = width;
+     img->height = height;
+     return img;
+}

Task/Grayscale-image/C/grayscale-image-3.c

@@ -0,0 +1,23 @@
+grayimage tograyscale(image img)
+{
+   unsigned int x, y;
+   grayimage timg;
+   double rc, gc, bc, l;
+   unsigned int ofs;
+
+   timg = alloc_grayimg(img->width, img->height);
+
+   for(x=0; x < img->width; x++)
+   {
+      for(y=0; y < img->height; y++)
+      {
+        ofs = (y * img->width) + x;
+        rc = (double) img->buf[ofs][0];
+        gc = (double) img->buf[ofs][1];
+        bc = (double) img->buf[ofs][2];
+        l = 0.2126*rc + 0.7152*gc + 0.0722*bc;
+        timg->buf[ofs][0] = (luminance) (l+0.5);
+      }
+   }
+   return timg;
+}

Task/Grayscale-image/C/grayscale-image-4.c

@@ -0,0 +1,22 @@
+image tocolor(grayimage img)
+{
+   unsigned int x, y;
+   image timg;
+   luminance l;
+   unsigned int ofs;
+
+   timg = alloc_img(img->width, img->height);
+
+   for(x=0; x < img->width; x++)
+   {
+      for(y=0; y < img->height; y++)
+      {
+        ofs = (y * img->width) + x;
+        l = img->buf[ofs][0];
+        timg->buf[ofs][0] = l;
+        timg->buf[ofs][1] = l;
+        timg->buf[ofs][2] = l;
+      }
+   }
+   return timg;
+}

Task/Grayscale-image/C/grayscale-image-5.c

@@ -0,0 +1 @@
+#define free_grayimg(IMG) free_img((image)(IMG))