DLLEXPORT int tjDecompress2()

in turbojpeg.c [1969:2015]

• 39 lines of code
• 17 McCabe index (conditional complexity)

DLLEXPORT int tjDecompress2(tjhandle handle, const unsigned char *jpegBuf,
                            unsigned long jpegSize, unsigned char *dstBuf,
                            int width, int pitch, int height, int pixelFormat,
                            int flags)
{
  static const char FUNCTION_NAME[] = "tjDecompress2";
  int i, retval = 0, jpegwidth, jpegheight, scaledw, scaledh;

  GET_DINSTANCE(handle);
  if ((this->init & DECOMPRESS) == 0)
    THROW("Instance has not been initialized for decompression");

  if (jpegBuf == NULL || jpegSize <= 0 || width < 0 || height < 0)
    THROW("Invalid argument");

  if (setjmp(this->jerr.setjmp_buffer)) {
    /* If we get here, the JPEG code has signaled an error. */
    retval = -1;  goto bailout;
  }

  jpeg_mem_src_tj(dinfo, jpegBuf, jpegSize);
  jpeg_read_header(dinfo, TRUE);
  jpegwidth = dinfo->image_width;  jpegheight = dinfo->image_height;
  if (width == 0) width = jpegwidth;
  if (height == 0) height = jpegheight;
  for (i = 0; i < NUMSF; i++) {
    scaledw = TJSCALED(jpegwidth, sf[i]);
    scaledh = TJSCALED(jpegheight, sf[i]);
    if (scaledw <= width && scaledh <= height)
      break;
  }
  if (i >= NUMSF)
    THROW("Could not scale down to desired image dimensions");

  processFlags(handle, flags, DECOMPRESS);

  if (tj3SetScalingFactor(handle, sf[i]) == -1)
    return -1;
  if (tj3SetCroppingRegion(handle, TJUNCROPPED) == -1)
    return -1;
  return tj3Decompress8(handle, jpegBuf, jpegSize, dstBuf, pitch, pixelFormat);

bailout:
  if (dinfo->global_state > DSTATE_START) jpeg_abort_decompress(dinfo);
  if (this->jerr.warning) retval = -1;
  return retval;
}