Bitmap File Format

To describe details of bitmap file structure, this site consists the following image for every time.

This image has following properties.

Bitmap File Structure

The first 54 bytes area highlighted with yellow background is a header of bitmap file. The left shown data is what the binary file looks like and the right shown data is a decoded version of binary file as ASCII characters set. Yellow background represents the separation of each field.

42 4d 36 00 30 00 00 00 00 00 36 00 00 00 28 00
00 00 00 04 00 00 00 04 00 00 01 00 18 00 00 00
00 00 00 00 30 00 74 12 00 00 74 12 00 00 00 00
00 00 00 00 00 00 39 42 44 38 42 44 3b 46 4a 3e

BM6.0.....6...(.
................
....0.t...t.....
......9BD8BD;FJ>

Here's a table explaining each field meaning. Bitmap file format adopts Little Endian format.

Bit Depth

Color Table / Palette

Binary Editor

C++ codes

namespace MyStandard
{
    typedef uint8_t BYTE;
	typedef uint16_t WORD;
	typedef uint32_t DWORD;
	typedef uint64_t QWORD;

	struct BITMAP_FILEHEADER
	{
		BYTE bfType[2]; 		// 0
		BYTE bfSize[4];		    // 2
		BYTE bfReserved1[2];	// 6
		BYTE bfReserved2[2];    // 8
		BYTE bfOffBits[4];  	// 10
	};

	struct BITMAP_INFOHEADER
	{
		BYTE biSize[4]; 		// 14
		BYTE biWidth[4];		// 18
		BYTE biHeight[4];		// 22
		BYTE biPlanes[2];       // 26
		BYTE biBitCount[2]; 	// 28
		BYTE biCompression[4];  // 30
		BYTE biSizeImage[4]; 	// 34
		BYTE biXPixPerMeter[4]; // 38
		BYTE biYPixPerMeter[4]; // 42
		BYTE biClrUsed[4];   	// 46
		BYTE biCirImportant[4]; // 50
	};

	struct BITMAP_HEADER {
		BITMAP_FILEHEADER file;
		BITMAP_INFOHEADER info;
	};

	// ...
}