Method initVC5LogTable

src/librawspeed/decompressors/VC5Decompressor.cpp:360–382

}

void VC5Decompressor::initVC5LogTable() {
  mVC5LogTable = decltype(mVC5LogTable)(
      [outputBits = outputBits](unsigned i, unsigned tableSize) {
        // The vanilla "inverse log" curve for decoding.
        auto normalizedCurve = [](auto normalizedI) {
          return (std::pow(113.0, normalizedI) - 1) / 112.0;
        };

        auto normalizeI = [tableSize](auto x) { return x / (tableSize - 1.0); };
        auto denormalizeY = [maxVal = std::numeric_limits<uint16_t>::max()](
                                auto y) { return maxVal * y; };
        // Adjust for output whitelevel bitdepth.
        auto rescaleY = [outputBits](auto y) {
          auto scale = 16 - outputBits;
          return y >> scale;
        };

        const auto naiveY = denormalizeY(normalizedCurve(normalizeI(i)));
        const auto intY = static_cast<unsigned int>(naiveY);
        const auto rescaledY = rescaleY(intY);
        return rescaledY;
      });
}

void VC5Decompressor::parseVC5() {
  mBs.setByteOrder(Endianness::big);