1 files changed, 156 insertions, 0 deletions
diff --git a/bitmap.c b/bitmap.c
new file mode 100644
index 0000000..3ca2236
--- /dev/null
+++ b/bitmap.c
@@ -0,0 +1,156 @@
+#include "bitmap.h"
+
+uint32_t bitmap_flip_byte(unsigned char* _v, int _c)
+{
+  uint32_t ret = 0;
+  uint32_t counter = (_c-1) * 8;
+
+  for(int i = 0; i < _c; i++)
+  {
+    ret |= (uint32_t)(_v[i] << (counter));
+    counter -= 8;
+  }
+
+  return ret;
+}//flip
+
+struct bitmap_pixel_data bitmap_read(char *_file)
+{
+  struct bitmap_pixel_data ret;
+  struct bitmap_file_header header;
+
+  ret.R = ret.G = ret.B = NULL;
+
+  FILE *bitmap = fopen(_file,"r");
+
+  if(!bitmap)
+    return ret;
+
+  header = bitmap_read_file_header(bitmap);
+
+  if(header.error)
+    return ret;
+
+  if(header.biBitCount != 24)
+    return ret;
+
+  if(header.biCompression != 0)
+    return ret;
+
+  ret = bitmap_read_pixel_data(bitmap, header);
+
+  fclose(bitmap);
+
+  return ret;
+}
+
+struct bitmap_file_header bitmap_read_file_header(FILE *_file)
+{
+  struct bitmap_file_header ret;
+  unsigned char fileheader[_HEADER_SIZE];
+  uint32_t      read_counter = 0;
+
+  ret.error = 1;
+
+  size_t tt = fread((void*)&fileheader, sizeof(char), _HEADER_SIZE, _file);
+  read_counter += _HEADER_SIZE;
+
+  if(!tt)
+    return ret;
+
+  //Copy file header
+  ret.bfType =          (uint16_t) bitmap_flip_byte(&fileheader[BF_TYPE], sizeof(ret.bfType));
+
+  if(ret.bfType != (uint16_t)IDENTIFIER)
+    return ret;
+
+  ret.bfSize =          (uint32_t) bitmap_flip_byte(&fileheader[BF_SIZE], sizeof(ret.bfSize));
+  ret.bfOffBits =      *(uint32_t*) &fileheader[BF_OFF_BITS];
+  ret.biSize =         *(uint32_t*) &fileheader[BI_SIZE];
+  ret.biWidth =        *(int32_t*) &fileheader[BI_WIDTH];
+  ret.biHeight =       *(int32_t*) &fileheader[BI_HEIGHT];
+  ret.biBitCount =     *(uint16_t*) &fileheader[BI_BIT_COUNT];
+  ret.biCompression =   (uint32_t) bitmap_flip_byte(&fileheader[BI_COMPRESSION], sizeof(ret.biCompression));
+  ret.biSizeImage =    *(uint32_t*) &fileheader[BI_SIZE_IMAGE];
+  ret.biClrUsed =       (uint32_t) bitmap_flip_byte(&fileheader[BI_CLR_USED], sizeof(ret.biClrUsed));
+  ret.biClrImportant =  (uint32_t) bitmap_flip_byte(&fileheader[BI_CLR_IMPORTANT], sizeof(ret.biClrImportant));
+
+
+  //Read to start of Pixel block
+  //This block contains Colormasks and Colortables.
+  ret.tablesc = ret.bfOffBits - read_counter;
+  ret.tables = malloc(sizeof(char)* ret.tablesc);
+  fread(ret.tables, sizeof(char), ret.tablesc, _file);
+  //////////
+
+  ret.error = 0;
+  return ret;
+}
+
+struct bitmap_pixel_data bitmap_read_pixel_data(FILE *_file, struct bitmap_file_header _header)
+{
+  uint32_t      **bitmap_buff;
+
+  struct bitmap_pixel_data ret;
+
+  uint32_t row_size = _header.biWidth * 3;
+  while(row_size%4)
+    row_size++;
+
+  ret.x = _header.biWidth;
+  ret.y = _header.biHeight < 0 ? -_header.biHeight: _header.biHeight;
+
+  //If biHeight > 0 Data starts with last row!!
+
+  //Allocate 2D array
+  //!!
+  //bitmap_buff indeces are flipped!! [y][x]!!!!!
+  bitmap_buff = malloc(sizeof(*bitmap_buff) * _header.biHeight);
+  for(int i = 0; i < ret.y; i++)
+  {
+    bitmap_buff[i] = malloc(sizeof(*bitmap_buff[i]) * _header.biWidth);
+  }
+
+  //Copy Bitmap into bitmap_buff
+  for(int row = 0; row < _header.biHeight; row++)
+  {
+    //printf("Row %i\n", row);
+    //fread(bitmap_buff[row], sizeof(char), row_size, bitmap);
+    for(int col = 0; col < _header.biWidth; col++)
+      fread(&bitmap_buff[row][col], 1, 3, _file);
+
+    for(int i = 0; i < row_size - (_header.biWidth * 3); i++) //read excess NULL-Bytes
+        fgetc(_file);
+  }
+
+  ret.x = _header.biWidth;
+  ret.y = _header.biHeight < 0 ? -_header.biHeight: _header.biHeight;
+
+  ret.R = malloc(sizeof(*ret.R) * ret.x);
+  ret.G = malloc(sizeof(*ret.G) * ret.x);
+  ret.B = malloc(sizeof(*ret.B) * ret.x);
+  for(int i = 0; i < ret.y; i++)
+  {
+    ret.R[i] = malloc(sizeof(*ret.R[i]) * ret.y);
+    ret.G[i] = malloc(sizeof(*ret.G[i]) * ret.y);
+    ret.B[i] = malloc(sizeof(*ret.B[i]) * ret.y);
+  }
+
+  for(int y = 0; y < ret.y; y++)
+  {
+    for(int x = 0; x < ret.x; x++)
+    {
+      int row = _header.biHeight > 0 ? (ret.y - 1) - y : y;
+
+      ret.R[x][y] = (bitmap_buff[row][x] & 0xff0000)>>16;
+      ret.G[x][y] = (bitmap_buff[row][x] & 0x00ff00)>>8;
+      ret.B[x][y] = (bitmap_buff[row][x] & 0x0000ff);
+    }
+  }
+
+  for(int i = 0; i < ret.y; i++)
+    free(bitmap_buff[i]);
+  free(bitmap_buff);
+
+  return ret;
+}