multimedia_20150427_hk2

#include <stdio.h>
#include <stdlib.h>

typedef struct _lbheader{
    unsigned short identifier;      // 0x0000
    unsigned int filesize;          // 0x0002
    unsigned int reserved;          // 0x0006
    unsigned int bitmap_dataoffset; // 0x000A
    unsigned int bitmap_headersize; // 0x000E
    unsigned int width;             // 0x0012
    unsigned int height;            // 0x0016
    unsigned short planes;          // 0x001A
    unsigned short bits_perpixel;   // 0x001C
    unsigned int compression;       // 0x001E
    unsigned int bitmap_datasize;   // 0x0022
    unsigned int hresolution;       // 0x0026
    unsigned int vresolution;       // 0x002A
    unsigned int usedcolors;        // 0x002E
    unsigned int importantcolors;   // 0x0032
    unsigned int palette;           // 0x0036
} __attribute__((packed,aligned(1))) lbheader;


int readbmp(char* filename, lbheader& hbmp, int mode, unsigned char* buffer)
{
    FILE* ifp;
    char c[128];
    unsigned char* ptr;

    sprintf(c, "%s", filename);
    ifp = fopen(c, "rb");
    if(ifp==NULL){
        printf("readbmp: file open error\n");
        return -1;
    }

    ptr = (unsigned char *)&hbmp;
    fread(ptr, sizeof(unsigned char), sizeof(lbheader), ifp);

    if(mode==1){
        fread(buffer, sizeof(unsigned char), (hbmp.width*hbmp.height*3), ifp);
    }
    else{
        fclose(ifp);
        return (hbmp.width*hbmp.height*3);
    }

    fclose(ifp);
    return 1;
}
int writebmp(char* filename, lbheader hbmp, unsigned char* buffer)
{
    FILE* ofp;
    char c[128];
    unsigned char* ptr;

    sprintf(c, "%s", filename);
    ofp = fopen(c, "wb");
    if(ofp==NULL){
        printf("writebmp: file open error\n");
        return -1;
    }

    //write header
    ptr = (unsigned char *)&hbmp;
    fwrite(ptr, sizeof(unsigned char), sizeof(lbheader), ofp);

    //write reverse pixel
    int i,j;
    for(i=0;i<hbmp.height;i++)
        for(j=0;j<hbmp.width;j++)
               fwrite(buffer+i*hbmp.width*3+(hbmp.width-j-1)*3, sizeof(unsigned char), 3, ofp);

    fclose(ofp);
    return 1;
}

int main(int argc, char *argv[])
{
  unsigned char* bimage;
  lbheader bmpinfo;
  if(argc == 2)
  {
          bimage = (unsigned char *)malloc(sizeof(unsigned char)*readbmp(argv[1], bmpinfo, 0, bimage));
          readbmp(argv[1], bmpinfo, 1, bimage);
  }
  else
  {
        bimage = (unsigned char *)malloc(sizeof(unsigned char)*readbmp("./default.bmp", bmpinfo, 0, bimage));
        readbmp("./default.bmp", bmpinfo, 1, bimage);
  }
  writebmp("./output.bmp",bmpinfo,bimage);

  //system("PAUSE");
  return 0;
}