C. Read and Write the BMP file code.

 

It is easy to read and write BMP file code in pure C code.

/*************************************** * ******************** <Br/> ** copyright (c) 2007, Shanghai <br/> ** file name: read_write_bmp _with_c.c <br/> ** Compilation: visual c ++/ansi c/iso c ++ <br/> ** Date: 2007.10.24 <br/> *********************************** * *************************/<br/> # include "stdio. H "<br/> # include" stdlib. H "<br/> # define pixpline 320 <br/> typedef struct tagrgbquad {// define the data type of each pixel <B R/> unsigned char rgbblue; <br/> unsigned char rgbgreen; <br/> unsigned char rgbred; <br/>} rgbquad; <br/> int BMP _read (unsigned char * image, int xsize, int ysize, char * filename) {<br/> char fname_bmp [128]; <br/> sprintf (fname_bmp, "%s.bmp", filename); </P> <p> file * FP; <br/> If (! (FP = fopen (fname_bmp, "rb") <br/> return-1; </P> <p> unsigned char header [54]; <br/> fread (header, sizeof (unsigned char), 54, FP); <br/> fread (image, sizeof (unsigned char), (size_t) (long) xsize * ysize * 3, FP); </P> <p> fclose (FP); <br/> return 0; <br/>}< br/> int BMP _write (unsigned char * image, int xsize, int ysize, char * filename) {<br/> unsigned char header [54] = {<br/> 0x42, 0x4d, 0, 0, 0, 0, 0, 0, 0, 0, 0, <br/> 54, 0, 0, 0, 40, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 24, 0, <br/> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, <br/> 0, 0, 0, 0 <br/> }; </P> <p> long file_size = (long) xsize * (long) ysize * 3 + 54; <br/> header [2] = (unsigned char) (file_size & 0x000000ff); <br/> header [3] = (file_size> 8) & 0x000000ff; <br/> header [4] = (file_size> 16) & 0x000000ff; <br/> head Er [5] = (file_size> 24) & 0x000000ff; </P> <p> long width = xsize; <br/> header [18] = width & 0x000000ff; <br/> header [19] = (width> 8) & 0x000000ff; <br/> header [20] = (width> 16) & 0x000000ff; <br/> header [21] = (width> 24) & 0x000000ff; </P> <p> long Height = ysize; <br/> header [22] = height & 0x000000ff; <br/> header [23] = (height> 8) & 0x000000ff; <br/> header [24] = (height> 16) & 0x000000f F; <br/> header [25] = (height> 24) & 0x000000ff; <br/> char fname_bmp [128]; <br/> sprintf (fname_bmp, "maid", filename); </P> <p> file * FP; <br/> If (! (FP = fopen (fname_bmp, "WB") <br/> return-1; </P> <p> fwrite (header, sizeof (unsigned char), 54, FP); <br/> fwrite (image, sizeof (unsigned char), (size_t) (long) xsize * ysize * 3, FP ); </P> <p> fclose (FP); <br/> return 0; <br/>}< br/> void clonebmp (unsigned char * image, int xsize, int ysize) <br/>{< br/> BMP _read (image, xsize, ysize, "orgbmp "); // orgbmp is the BMP file name in the current directory <br/> BMP _write (image, xsize, ysize, "C Lone_bmp "); // clone_bmp is the cloned BMP file name <br/>}< br/> /********************** **************************************** * ************* <br/> * Name: youwritetobmp () <br/> * function: Write a BMP file <br/> * entry parameter: rgbquad * pixarr ---- pointer to the pixel array to be written, int xsize ---- image width, int ysize ---- Image Height, char * filename -- image name <br/> * exit parameter: None <br/> * return value:-1: error; 0: correct <br/> *********************************** **************************************** */<br /> Int youwritetobmp (rgbquad * pixarr, int xsize, int ysize, char * filename) {<br/> unsigned char header [54] = {<br/> 0x42, 0x4d, 0, 0, 0, 0, 0, 0, 0, 0, <br/> 54, 0, 0, 0, 40, 0, 0, 0, 0, 0, <br/> 0, 0, 0, 0, 0, 0, 1, 0, 24, 0, <br/> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, <br/> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, <br/> 0, 0, 0, 0 <br/>}; <br/> int I; <br/> Int J; <br/> long file_size = (long) xsize * (long) ysiz E * 3 + 54; <br/> header [2] = (unsigned char) (file_size & 0x000000ff); <br/> header [3] = (file_size> 8) & 0x000000ff; <br/> header [4] = (file_size> 16) & 0x000000ff; <br/> header [5] = (file_size> 24) & 0x000000ff; </P> <p> long width; <br/> If (! (Xsize % 4) width = xsize; <br/> else width = xsize + (4-xsize % 4); // if it is not a multiple of 4, convert to a multiple of 4 <br/> header [18] = width & 0x000000ff; <br/> header [19] = (width> 8) & 0x000000ff; <br/> header [20] = (width> 16) & 0x000000ff; <br/> header [21] = (width> 24) & 0x000000ff; </P> <p> long Height = ysize; <br/> header [22] = height & 0x000000ff; <br/> header [23] = (height> 8) & 0x000000ff; <br/> header [24] = (height> 16) & 0x000000ff; <br/> header [25] = (height> 24) & 0x000000ff; <br/> char fname_bmp [128]; <br/> sprintf (fname_bmp, "maid", filename); </P> <p> file * FP; <br/> If (! (FP = fopen (fname_bmp, "WB") <br/> return-1; </P> <p> fwrite (header, sizeof (unsigned char), 54, FP); <br/> rgbquad zero = {0, 0}; // insufficient bytes, filled with zero </P> <p> for (j = 0; j <ysize; j ++) {<br/> If (! (Xsize % 4) {<br/> for (I = 0; I <xsize; I ++) {<br/> fwrite (pixarr + I, sizeof (rgbquad), 1, FP); <br/>}< br/> else <br/>{< br/> for (I = 0; I <xsize; I ++) {<br/> fwrite (pixarr + I, sizeof (rgbquad), 1, FP ); <br/>}< br/> for (I = xsize; I <xsize + (4-xsize % 4); I ++) {<br/> fwrite (& zero, sizeof (rgbquad), 1, FP); <br/>}</P> <p> fclose (FP ); <br/> return 0; <br/>}< br/> int main () {<br/> unsigned char * image; <br/> int xsize = 320; <br/> int ysize = 163; <br/> rgbquad pixarray [pixpline]; // array of a row of pixel values <br/> image = (unsigned char *) malloc (size_t) xsize * ysize * 3); <br/> If (image = NULL) <br/> return-1; <br/> clonebmp (image, xsize, ysize); // function 1: copy an image <br/> youwritetobmp (pixarray, xsize, ysize, "yourimage"); // function 2: accurately draws pixels. pixel values are in the pixarray </P> <p> free (image); <br/> return-1; <br/>}