f76hmto4.cpp

#include <cstdio>
#include <vector>

static const unsigned char ddsHeader[128] =
{
  0x44, 0x44, 0x53, 0x20, 0x7C, 0x00, 0x00, 0x00,
  0x0F, 0x10, 0x02, 0x00, 0x21, 0x19, 0x00, 0x00,
  0x21, 0x19, 0x00, 0x00, 0x84, 0x64, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x4E, 0x56, 0x54, 0x33,
  0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00, 0x00,
  0x04, 0x00, 0x00, 0x00, 0x72, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

int main(int argc, char **argv)
{
  if (argc != 3)
    return 1;
  std::vector< unsigned short > inBuf(6432 * 6432 + 64, 0);
  std::vector< unsigned int > outBuf(6433 * 6433 + 32, 0);
  std::FILE *f = std::fopen(argv[1], "rb");
  if (!f)
    return 1;
  std::fread(inBuf.data(), sizeof(unsigned short), inBuf.size(), f);
  std::fclose(f);
  for (unsigned int i = 0; i < 128; i++)
    outBuf[i >> 2] |= (unsigned int) ddsHeader[i] << ((i & 3) << 3);
  for (int y = 0; y < 6433; y++)
  {
    for (int x = 0; x < 6433; x++)
    {
      int     xc = x + 16;
      int     yc = y - 16;
      xc = (xc > 0 ? (xc < 6431 ? xc : 6431) : 0);
      yc = (yc > 0 ? (yc < 6431 ? yc : 6431) : 0);
      int     c = inBuf[yc * 6432 + xc + 64];
      union
      {
        unsigned int  n;
        float   f;
      }
      tmp;
      tmp.f = float(c) / 65535.0f;
      outBuf[y * 6433 + x + 32] = tmp.n;
    }
  }
  f = std::fopen(argv[2], "wb");
  if (!f)
    return 1;
  std::fwrite(outBuf.data(), sizeof(unsigned int), outBuf.size(), f);
  std::fclose(f);
  return 0;
}