Function read_image

src/doc/image_io.cpp:95–187

}

Image* read_image(std::istream& is, bool setId)
{
  ObjectId id = read32(is);
  int pixelFormat = read8(is);          // Pixel format
  int width = read16(is);               // Width
  int height = read16(is);              // Height
  uint32_t maskColor = read32(is);      // Mask color

  if ((pixelFormat != IMAGE_RGB &&
       pixelFormat != IMAGE_GRAYSCALE &&
       pixelFormat != IMAGE_INDEXED &&
       pixelFormat != IMAGE_BITMAP) ||
      (width < 1 || height < 1) ||
      (width > 0xfffff || height > 0xfffff))
    return nullptr;

  std::unique_ptr<Image> image(Image::create(static_cast<PixelFormat>(pixelFormat), width, height));
  int rowSize = image->getRowStrideSize();

#if 0
  {
    for (int c=0; c<image->height(); c++)
      is.read((char*)image->getPixelAddress(0, c), rowSize);
  }
#else
  {
    int avail_bytes = read32(is);

    z_stream zstream;
    zstream.zalloc = (alloc_func)0;
    zstream.zfree  = (free_func)0;
    zstream.opaque = (voidpf)0;

    int err = inflateInit(&zstream);
    if (err != Z_OK)
      throw base::Exception("ZLib error %d in inflateInit().", err);

    int uncompressed_size = image->height() * rowSize;
    int uncompressed_offset = 0;
    int remain = avail_bytes;

    std::vector<uint8_t> compressed(4096);
    uint8_t* address = image->getPixelAddress(0, 0);
    uint8_t* address_end = image->getPixelAddress(0, 0) + uncompressed_size;

    while (remain > 0) {
      int len = MIN(remain, (int)compressed.size());
      if (is.read((char*)&compressed[0], len).fail()) {
        ASSERT(false);
        throw base::Exception("Error reading stream to restore image");
      }

      int bytes_read = (int)is.gcount();
      if (bytes_read == 0) {
        ASSERT(remain == 0);
        break;
      }