ITkPixEncoding Namespace Reference

Functions
constexpr std::size_t	LookUpTableSize (1<< 16)
template<std::size_t Length, typename Generator>
constexpr auto	lut (Generator &&f)
constexpr uint32_t	one_bit (uint32_t v)
constexpr void	prepByte (uint32_t word, uint32_t b[8])
std::array< uint32_t, 8 >	prepByte (uint32_t word)
uint32_t constexpr	encode (uint32_t decoded, uint32_t &encoded)
auto	create_lut_encode (bool length=false)

Variables
template<std::size_t Length>
constexpr auto	LutLen
template<std::size_t Length>
constexpr auto	LutBTree
constexpr std::array< uint32_t, LookUpTableSize >	ITkPixV2QCoreEncodingLUT_Tree = LutBTree<LookUpTableSize>
constexpr std::array< uint32_t, LookUpTableSize >	ITkPixV2QCoreEncodingLUT_Length = LutLen<LookUpTableSize>

Function Documentation

create_lut_encode()

auto ITkPixEncoding::create_lut_encode ( bool length = false )

inline

Definition at line 88 of file ITkPixQCoreEncodingLUT.h.

                                                       {
        std::array<uint32_t, LookUpTableSize> lut;
        lut[0] = 0;
        for (uint32_t i = 1; i < 1 << 16; i++) {
            uint32_t encoded;
            uint64_t len = encode(i, encoded);
            lut[i] = length ? len : encoded;
        }
        return lut;
    }

encode()

uint32_t constexpr ITkPixEncoding::encode ( uint32_t decoded, uint32_t & encoded )

constexpr

Definition at line 54 of file ITkPixQCoreEncodingLUT.h.

                                                          {
        uint32_t b[8];
        prepByte(decoded, b);
        //
        uint32_t S1 = (one_bit(b[0] | b[1] | b[2] | b[3]) << 1) | one_bit(b[4] | b[5] | b[6] | b[7]);
        uint32_t S2t = (one_bit(b[0] | b[1]) << 1) | one_bit(b[2] | b[3]);
        uint32_t S2b = (one_bit(b[4] | b[5]) << 1) | one_bit(b[6] | b[7]);
        uint32_t S3tl = (one_bit(b[0]) << 1) | one_bit(b[1]);
        uint32_t S3tr = (one_bit(b[2]) << 1) | one_bit(b[3]);
        uint32_t S3bl = (one_bit(b[4]) << 1) | one_bit(b[5]);
        uint32_t S3br = (one_bit(b[6]) << 1) | one_bit(b[7]);
 
        uint32_t pos = 0;
        encoded = 0;
 
        auto writeTwo = [&](uint32_t src) {
            if (src == 0b01) {
                encoded |= (0b0) << (28 - pos);
                pos++;
            } else {
                encoded |= (src & 0x3) << (28 - pos);
                pos += 2;
            }
        };
        for(auto & val:{
            S1, S2t, S3tl, S3tr, b[0], b[1],b[2], b[3],
            S2b, S3bl, S3br,b[4], b[5], b[6], b[7]
        }) if(val) writeTwo(val);
        return pos;
    }

LookUpTableSize()

std::size_t ITkPixEncoding::LookUpTableSize ( 1<< 16 )

constexpr

lut()

template<std::size_t Length, typename Generator>

auto ITkPixEncoding::lut ( Generator && f )

constexpr

Definition at line 19 of file ITkPixQCoreEncodingLUT.h.

                                     {
      using content_type = decltype(f(std::size_t{0}));
      std::array<content_type, Length> arr;
      using namespace std::ranges;
      auto rangy = views::iota(std::size_t{0}, Length) // Generate a sequence
                 | views::transform(std::forward<Generator>(f)); // Transform using our generator
      copy(rangy, arr.begin());
      return arr;
  }

one_bit()

uint32_t ITkPixEncoding::one_bit ( uint32_t v )

constexpr

Definition at line 30 of file ITkPixQCoreEncodingLUT.h.

                       {
      return v!=0;
    }

prepByte() [1/2]

std::array< uint32_t, 8 > ITkPixEncoding::prepByte

(

uint32_t

word

)

Definition at line 44 of file ITkPixQCoreEncodingLUT.h.

    {
      std::array<uint32_t, 8> b;
      prepByte(word, b.data());
      return b;
    }

prepByte() [2/2]

void ITkPixEncoding::prepByte ( uint32_t word, uint32_t b[8] )

constexpr

Definition at line 38 of file ITkPixQCoreEncodingLUT.h.

                                                         {
      for(int i = 0 ;i<8;i++) {
        b[i] =  ((word >> (2*i)) & 0x1) << 1 | ((word >> (2*i+1)) & 0x1);
      }
    }

Variable Documentation

ITkPixV2QCoreEncodingLUT_Length

std::array<uint32_t, LookUpTableSize > ITkPixEncoding::ITkPixV2QCoreEncodingLUT_Length = LutLen<LookUpTableSize>

constexpr

Definition at line 116 of file ITkPixQCoreEncodingLUT.h.

ITkPixV2QCoreEncodingLUT_Tree

std::array<uint32_t, LookUpTableSize > ITkPixEncoding::ITkPixV2QCoreEncodingLUT_Tree = LutBTree<LookUpTableSize>

constexpr

Definition at line 115 of file ITkPixQCoreEncodingLUT.h.

LutBTree

template<std::size_t Length>

auto ITkPixEncoding::LutBTree

constexpr

Initial value:

= lut<Length>([](uint32_t i){
        uint32_t encoded;
        uint64_t len = encode(i, encoded);
        return encoded >> (30 - len);
    })

Definition at line 108 of file ITkPixQCoreEncodingLUT.h.

LutLen

template<std::size_t Length>

auto ITkPixEncoding::LutLen

constexpr

Initial value:

= lut<Length>([](uint32_t i){
        uint32_t encoded;
        return encode(i, encoded);
    })

Definition at line 102 of file ITkPixQCoreEncodingLUT.h.