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/*----------------------------------------------------------------------------*/
/**
* This confidential and proprietary software may be used only as
* authorised by a licensing agreement from ARM Limited
* (C) COPYRIGHT 2011-2012 ARM Limited
* ALL RIGHTS RESERVED
*
* The entire notice above must be reproduced on all authorised
* copies and copies may only be made to the extent permitted
* by a licensing agreement from ARM Limited.
*
* @brief Functions to encode/decode data using Bounded Integer Sequence
* Encoding.
*/
/*----------------------------------------------------------------------------*/
#include "astc_codec_internals.h"
// unpacked quint triplets <low,middle,high> for each packed-quint value
static const uint8_t quints_of_integer[128][3] = {
{0, 0, 0}, {1, 0, 0}, {2, 0, 0}, {3, 0, 0},
{4, 0, 0}, {0, 4, 0}, {4, 4, 0}, {4, 4, 4},
{0, 1, 0}, {1, 1, 0}, {2, 1, 0}, {3, 1, 0},
{4, 1, 0}, {1, 4, 0}, {4, 4, 1}, {4, 4, 4},
{0, 2, 0}, {1, 2, 0}, {2, 2, 0}, {3, 2, 0},
{4, 2, 0}, {2, 4, 0}, {4, 4, 2}, {4, 4, 4},
{0, 3, 0}, {1, 3, 0}, {2, 3, 0}, {3, 3, 0},
{4, 3, 0}, {3, 4, 0}, {4, 4, 3}, {4, 4, 4},
{0, 0, 1}, {1, 0, 1}, {2, 0, 1}, {3, 0, 1},
{4, 0, 1}, {0, 4, 1}, {4, 0, 4}, {0, 4, 4},
{0, 1, 1}, {1, 1, 1}, {2, 1, 1}, {3, 1, 1},
{4, 1, 1}, {1, 4, 1}, {4, 1, 4}, {1, 4, 4},
{0, 2, 1}, {1, 2, 1}, {2, 2, 1}, {3, 2, 1},
{4, 2, 1}, {2, 4, 1}, {4, 2, 4}, {2, 4, 4},
{0, 3, 1}, {1, 3, 1}, {2, 3, 1}, {3, 3, 1},
{4, 3, 1}, {3, 4, 1}, {4, 3, 4}, {3, 4, 4},
{0, 0, 2}, {1, 0, 2}, {2, 0, 2}, {3, 0, 2},
{4, 0, 2}, {0, 4, 2}, {2, 0, 4}, {3, 0, 4},
{0, 1, 2}, {1, 1, 2}, {2, 1, 2}, {3, 1, 2},
{4, 1, 2}, {1, 4, 2}, {2, 1, 4}, {3, 1, 4},
{0, 2, 2}, {1, 2, 2}, {2, 2, 2}, {3, 2, 2},
{4, 2, 2}, {2, 4, 2}, {2, 2, 4}, {3, 2, 4},
{0, 3, 2}, {1, 3, 2}, {2, 3, 2}, {3, 3, 2},
{4, 3, 2}, {3, 4, 2}, {2, 3, 4}, {3, 3, 4},
{0, 0, 3}, {1, 0, 3}, {2, 0, 3}, {3, 0, 3},
{4, 0, 3}, {0, 4, 3}, {0, 0, 4}, {1, 0, 4},
{0, 1, 3}, {1, 1, 3}, {2, 1, 3}, {3, 1, 3},
{4, 1, 3}, {1, 4, 3}, {0, 1, 4}, {1, 1, 4},
{0, 2, 3}, {1, 2, 3}, {2, 2, 3}, {3, 2, 3},
{4, 2, 3}, {2, 4, 3}, {0, 2, 4}, {1, 2, 4},
{0, 3, 3}, {1, 3, 3}, {2, 3, 3}, {3, 3, 3},
{4, 3, 3}, {3, 4, 3}, {0, 3, 4}, {1, 3, 4},
};
// packed quint-value for every unpacked quint-triplet
// indexed by [high][middle][low]
static const uint8_t integer_of_quints[5][5][5] = {
{
{0, 1, 2, 3, 4,},
{8, 9, 10, 11, 12,},
{16, 17, 18, 19, 20,},
{24, 25, 26, 27, 28,},
{5, 13, 21, 29, 6,},
},
{
{32, 33, 34, 35, 36,},
{40, 41, 42, 43, 44,},
{48, 49, 50, 51, 52,},
{56, 57, 58, 59, 60,},
{37, 45, 53, 61, 14,},
},
{
{64, 65, 66, 67, 68,},
{72, 73, 74, 75, 76,},
{80, 81, 82, 83, 84,},
{88, 89, 90, 91, 92,},
{69, 77, 85, 93, 22,},
},
{
{96, 97, 98, 99, 100,},
{104, 105, 106, 107, 108,},
{112, 113, 114, 115, 116,},
{120, 121, 122, 123, 124,},
{101, 109, 117, 125, 30,},
},
{
{102, 103, 70, 71, 38,},
{110, 111, 78, 79, 46,},
{118, 119, 86, 87, 54,},
{126, 127, 94, 95, 62,},
{39, 47, 55, 63, 31,},
},
};
// unpacked trit quintuplets <low,_,_,_,high> for each packed-quint value
static const uint8_t trits_of_integer[256][5] = {
{0, 0, 0, 0, 0}, {1, 0, 0, 0, 0}, {2, 0, 0, 0, 0}, {0, 0, 2, 0, 0},
{0, 1, 0, 0, 0}, {1, 1, 0, 0, 0}, {2, 1, 0, 0, 0}, {1, 0, 2, 0, 0},
{0, 2, 0, 0, 0}, {1, 2, 0, 0, 0}, {2, 2, 0, 0, 0}, {2, 0, 2, 0, 0},
{0, 2, 2, 0, 0}, {1, 2, 2, 0, 0}, {2, 2, 2, 0, 0}, {2, 0, 2, 0, 0},
{0, 0, 1, 0, 0}, {1, 0, 1, 0, 0}, {2, 0, 1, 0, 0}, {0, 1, 2, 0, 0},
{0, 1, 1, 0, 0}, {1, 1, 1, 0, 0}, {2, 1, 1, 0, 0}, {1, 1, 2, 0, 0},
{0, 2, 1, 0, 0}, {1, 2, 1, 0, 0}, {2, 2, 1, 0, 0}, {2, 1, 2, 0, 0},
{0, 0, 0, 2, 2}, {1, 0, 0, 2, 2}, {2, 0, 0, 2, 2}, {0, 0, 2, 2, 2},
{0, 0, 0, 1, 0}, {1, 0, 0, 1, 0}, {2, 0, 0, 1, 0}, {0, 0, 2, 1, 0},
{0, 1, 0, 1, 0}, {1, 1, 0, 1, 0}, {2, 1, 0, 1, 0}, {1, 0, 2, 1, 0},
{0, 2, 0, 1, 0}, {1, 2, 0, 1, 0}, {2, 2, 0, 1, 0}, {2, 0, 2, 1, 0},
{0, 2, 2, 1, 0}, {1, 2, 2, 1, 0}, {2, 2, 2, 1, 0}, {2, 0, 2, 1, 0},
{0, 0, 1, 1, 0}, {1, 0, 1, 1, 0}, {2, 0, 1, 1, 0}, {0, 1, 2, 1, 0},
{0, 1, 1, 1, 0}, {1, 1, 1, 1, 0}, {2, 1, 1, 1, 0}, {1, 1, 2, 1, 0},
{0, 2, 1, 1, 0}, {1, 2, 1, 1, 0}, {2, 2, 1, 1, 0}, {2, 1, 2, 1, 0},
{0, 1, 0, 2, 2}, {1, 1, 0, 2, 2}, {2, 1, 0, 2, 2}, {1, 0, 2, 2, 2},
{0, 0, 0, 2, 0}, {1, 0, 0, 2, 0}, {2, 0, 0, 2, 0}, {0, 0, 2, 2, 0},
{0, 1, 0, 2, 0}, {1, 1, 0, 2, 0}, {2, 1, 0, 2, 0}, {1, 0, 2, 2, 0},
{0, 2, 0, 2, 0}, {1, 2, 0, 2, 0}, {2, 2, 0, 2, 0}, {2, 0, 2, 2, 0},
{0, 2, 2, 2, 0}, {1, 2, 2, 2, 0}, {2, 2, 2, 2, 0}, {2, 0, 2, 2, 0},
{0, 0, 1, 2, 0}, {1, 0, 1, 2, 0}, {2, 0, 1, 2, 0}, {0, 1, 2, 2, 0},
{0, 1, 1, 2, 0}, {1, 1, 1, 2, 0}, {2, 1, 1, 2, 0}, {1, 1, 2, 2, 0},
{0, 2, 1, 2, 0}, {1, 2, 1, 2, 0}, {2, 2, 1, 2, 0}, {2, 1, 2, 2, 0},
{0, 2, 0, 2, 2}, {1, 2, 0, 2, 2}, {2, 2, 0, 2, 2}, {2, 0, 2, 2, 2},
{0, 0, 0, 0, 2}, {1, 0, 0, 0, 2}, {2, 0, 0, 0, 2}, {0, 0, 2, 0, 2},
{0, 1, 0, 0, 2}, {1, 1, 0, 0, 2}, {2, 1, 0, 0, 2}, {1, 0, 2, 0, 2},
{0, 2, 0, 0, 2}, {1, 2, 0, 0, 2}, {2, 2, 0, 0, 2}, {2, 0, 2, 0, 2},
{0, 2, 2, 0, 2}, {1, 2, 2, 0, 2}, {2, 2, 2, 0, 2}, {2, 0, 2, 0, 2},
{0, 0, 1, 0, 2}, {1, 0, 1, 0, 2}, {2, 0, 1, 0, 2}, {0, 1, 2, 0, 2},
{0, 1, 1, 0, 2}, {1, 1, 1, 0, 2}, {2, 1, 1, 0, 2}, {1, 1, 2, 0, 2},
{0, 2, 1, 0, 2}, {1, 2, 1, 0, 2}, {2, 2, 1, 0, 2}, {2, 1, 2, 0, 2},
{0, 2, 2, 2, 2}, {1, 2, 2, 2, 2}, {2, 2, 2, 2, 2}, {2, 0, 2, 2, 2},
{0, 0, 0, 0, 1}, {1, 0, 0, 0, 1}, {2, 0, 0, 0, 1}, {0, 0, 2, 0, 1},
{0, 1, 0, 0, 1}, {1, 1, 0, 0, 1}, {2, 1, 0, 0, 1}, {1, 0, 2, 0, 1},
{0, 2, 0, 0, 1}, {1, 2, 0, 0, 1}, {2, 2, 0, 0, 1}, {2, 0, 2, 0, 1},
{0, 2, 2, 0, 1}, {1, 2, 2, 0, 1}, {2, 2, 2, 0, 1}, {2, 0, 2, 0, 1},
{0, 0, 1, 0, 1}, {1, 0, 1, 0, 1}, {2, 0, 1, 0, 1}, {0, 1, 2, 0, 1},
{0, 1, 1, 0, 1}, {1, 1, 1, 0, 1}, {2, 1, 1, 0, 1}, {1, 1, 2, 0, 1},
{0, 2, 1, 0, 1}, {1, 2, 1, 0, 1}, {2, 2, 1, 0, 1}, {2, 1, 2, 0, 1},
{0, 0, 1, 2, 2}, {1, 0, 1, 2, 2}, {2, 0, 1, 2, 2}, {0, 1, 2, 2, 2},
{0, 0, 0, 1, 1}, {1, 0, 0, 1, 1}, {2, 0, 0, 1, 1}, {0, 0, 2, 1, 1},
{0, 1, 0, 1, 1}, {1, 1, 0, 1, 1}, {2, 1, 0, 1, 1}, {1, 0, 2, 1, 1},
{0, 2, 0, 1, 1}, {1, 2, 0, 1, 1}, {2, 2, 0, 1, 1}, {2, 0, 2, 1, 1},
{0, 2, 2, 1, 1}, {1, 2, 2, 1, 1}, {2, 2, 2, 1, 1}, {2, 0, 2, 1, 1},
{0, 0, 1, 1, 1}, {1, 0, 1, 1, 1}, {2, 0, 1, 1, 1}, {0, 1, 2, 1, 1},
{0, 1, 1, 1, 1}, {1, 1, 1, 1, 1}, {2, 1, 1, 1, 1}, {1, 1, 2, 1, 1},
{0, 2, 1, 1, 1}, {1, 2, 1, 1, 1}, {2, 2, 1, 1, 1}, {2, 1, 2, 1, 1},
{0, 1, 1, 2, 2}, {1, 1, 1, 2, 2}, {2, 1, 1, 2, 2}, {1, 1, 2, 2, 2},
{0, 0, 0, 2, 1}, {1, 0, 0, 2, 1}, {2, 0, 0, 2, 1}, {0, 0, 2, 2, 1},
{0, 1, 0, 2, 1}, {1, 1, 0, 2, 1}, {2, 1, 0, 2, 1}, {1, 0, 2, 2, 1},
{0, 2, 0, 2, 1}, {1, 2, 0, 2, 1}, {2, 2, 0, 2, 1}, {2, 0, 2, 2, 1},
{0, 2, 2, 2, 1}, {1, 2, 2, 2, 1}, {2, 2, 2, 2, 1}, {2, 0, 2, 2, 1},
{0, 0, 1, 2, 1}, {1, 0, 1, 2, 1}, {2, 0, 1, 2, 1}, {0, 1, 2, 2, 1},
{0, 1, 1, 2, 1}, {1, 1, 1, 2, 1}, {2, 1, 1, 2, 1}, {1, 1, 2, 2, 1},
{0, 2, 1, 2, 1}, {1, 2, 1, 2, 1}, {2, 2, 1, 2, 1}, {2, 1, 2, 2, 1},
{0, 2, 1, 2, 2}, {1, 2, 1, 2, 2}, {2, 2, 1, 2, 2}, {2, 1, 2, 2, 2},
{0, 0, 0, 1, 2}, {1, 0, 0, 1, 2}, {2, 0, 0, 1, 2}, {0, 0, 2, 1, 2},
{0, 1, 0, 1, 2}, {1, 1, 0, 1, 2}, {2, 1, 0, 1, 2}, {1, 0, 2, 1, 2},
{0, 2, 0, 1, 2}, {1, 2, 0, 1, 2}, {2, 2, 0, 1, 2}, {2, 0, 2, 1, 2},
{0, 2, 2, 1, 2}, {1, 2, 2, 1, 2}, {2, 2, 2, 1, 2}, {2, 0, 2, 1, 2},
{0, 0, 1, 1, 2}, {1, 0, 1, 1, 2}, {2, 0, 1, 1, 2}, {0, 1, 2, 1, 2},
{0, 1, 1, 1, 2}, {1, 1, 1, 1, 2}, {2, 1, 1, 1, 2}, {1, 1, 2, 1, 2},
{0, 2, 1, 1, 2}, {1, 2, 1, 1, 2}, {2, 2, 1, 1, 2}, {2, 1, 2, 1, 2},
{0, 2, 2, 2, 2}, {1, 2, 2, 2, 2}, {2, 2, 2, 2, 2}, {2, 1, 2, 2, 2},
};
// packed trit-value for every unpacked trit-quintuplet
// indexed by [high][][][][low]
static const uint8_t integer_of_trits[3][3][3][3][3] = {
{
{
{
{0, 1, 2,},
{4, 5, 6,},
{8, 9, 10,},
},
{
{16, 17, 18,},
{20, 21, 22,},
{24, 25, 26,},
},
{
{3, 7, 15,},
{19, 23, 27,},
{12, 13, 14,},
},
},
{
{
{32, 33, 34,},
{36, 37, 38,},
{40, 41, 42,},
},
{
{48, 49, 50,},
{52, 53, 54,},
{56, 57, 58,},
},
{
{35, 39, 47,},
{51, 55, 59,},
{44, 45, 46,},
},
},
{
{
{64, 65, 66,},
{68, 69, 70,},
{72, 73, 74,},
},
{
{80, 81, 82,},
{84, 85, 86,},
{88, 89, 90,},
},
{
{67, 71, 79,},
{83, 87, 91,},
{76, 77, 78,},
},
},
},
{
{
{
{128, 129, 130,},
{132, 133, 134,},
{136, 137, 138,},
},
{
{144, 145, 146,},
{148, 149, 150,},
{152, 153, 154,},
},
{
{131, 135, 143,},
{147, 151, 155,},
{140, 141, 142,},
},
},
{
{
{160, 161, 162,},
{164, 165, 166,},
{168, 169, 170,},
},
{
{176, 177, 178,},
{180, 181, 182,},
{184, 185, 186,},
},
{
{163, 167, 175,},
{179, 183, 187,},
{172, 173, 174,},
},
},
{
{
{192, 193, 194,},
{196, 197, 198,},
{200, 201, 202,},
},
{
{208, 209, 210,},
{212, 213, 214,},
{216, 217, 218,},
},
{
{195, 199, 207,},
{211, 215, 219,},
{204, 205, 206,},
},
},
},
{
{
{
{96, 97, 98,},
{100, 101, 102,},
{104, 105, 106,},
},
{
{112, 113, 114,},
{116, 117, 118,},
{120, 121, 122,},
},
{
{99, 103, 111,},
{115, 119, 123,},
{108, 109, 110,},
},
},
{
{
{224, 225, 226,},
{228, 229, 230,},
{232, 233, 234,},
},
{
{240, 241, 242,},
{244, 245, 246,},
{248, 249, 250,},
},
{
{227, 231, 239,},
{243, 247, 251,},
{236, 237, 238,},
},
},
{
{
{28, 29, 30,},
{60, 61, 62,},
{92, 93, 94,},
},
{
{156, 157, 158,},
{188, 189, 190,},
{220, 221, 222,},
},
{
{31, 63, 127,},
{159, 191, 255,},
{252, 253, 254,},
},
},
},
};
void find_number_of_bits_trits_quints(int quantization_level, int *bits, int *trits, int *quints)
{
*bits = 0;
*trits = 0;
*quints = 0;
switch (quantization_level)
{
case QUANT_2:
*bits = 1;
break;
case QUANT_3:
*bits = 0;
*trits = 1;
break;
case QUANT_4:
*bits = 2;
break;
case QUANT_5:
*bits = 0;
*quints = 1;
break;
case QUANT_6:
*bits = 1;
*trits = 1;
break;
case QUANT_8:
*bits = 3;
break;
case QUANT_10:
*bits = 1;
*quints = 1;
break;
case QUANT_12:
*bits = 2;
*trits = 1;
break;
case QUANT_16:
*bits = 4;
break;
case QUANT_20:
*bits = 2;
*quints = 1;
break;
case QUANT_24:
*bits = 3;
*trits = 1;
break;
case QUANT_32:
*bits = 5;
break;
case QUANT_40:
*bits = 3;
*quints = 1;
break;
case QUANT_48:
*bits = 4;
*trits = 1;
break;
case QUANT_64:
*bits = 6;
break;
case QUANT_80:
*bits = 4;
*quints = 1;
break;
case QUANT_96:
*bits = 5;
*trits = 1;
break;
case QUANT_128:
*bits = 7;
break;
case QUANT_160:
*bits = 5;
*quints = 1;
break;
case QUANT_192:
*bits = 6;
*trits = 1;
break;
case QUANT_256:
*bits = 8;
break;
}
}
// routine to write up to 8 bits
static inline void write_bits(int value, int bitcount, int bitoffset, uint8_t * ptr)
{
int mask = (1 << bitcount) - 1;
value &= mask;
ptr += bitoffset >> 3;
bitoffset &= 7;
value <<= bitoffset;
mask <<= bitoffset;
mask = ~mask;
ptr[0] &= mask;
ptr[0] |= value;
ptr[1] &= mask >> 8;
ptr[1] |= value >> 8;
}
// routine to read up to 8 bits
static inline int read_bits(int bitcount, int bitoffset, const uint8_t * ptr)
{
int mask = (1 << bitcount) - 1;
ptr += bitoffset >> 3;
bitoffset &= 7;
int value = ptr[0] | (ptr[1] << 8);
value >>= bitoffset;
value &= mask;
return value;
}
void encode_ise(int quantization_level, int elements, const uint8_t * input_data, uint8_t * output_data, int bit_offset)
{
int i;
uint8_t lowparts[64];
uint8_t highparts[69]; // 64 elements + 5 elements for padding
uint8_t tq_blocks[22]; // trit-blocks or quint-blocks
int bits, trits, quints;
find_number_of_bits_trits_quints(quantization_level, &bits, &trits, &quints);
for (i = 0; i < elements; i++)
{
lowparts[i] = input_data[i] & ((1 << bits) - 1);
highparts[i] = input_data[i] >> bits;
}
for (i = elements; i < elements + 5; i++)
highparts[i] = 0; // padding before we start constructing trit-blocks or quint-blocks
// construct trit-blocks or quint-blocks as necessary
if (trits)
{
int trit_blocks = (elements + 4) / 5;
for (i = 0; i < trit_blocks; i++)
tq_blocks[i] = integer_of_trits[highparts[5 * i + 4]][highparts[5 * i + 3]][highparts[5 * i + 2]][highparts[5 * i + 1]][highparts[5 * i]];
}
if (quints)
{
int quint_blocks = (elements + 2) / 3;
for (i = 0; i < quint_blocks; i++)
tq_blocks[i] = integer_of_quints[highparts[3 * i + 2]][highparts[3 * i + 1]][highparts[3 * i]];
}
// then, write out the actual bits.
int lcounter = 0;
int hcounter = 0;
for (i = 0; i < elements; i++)
{
write_bits(lowparts[i], bits, bit_offset, output_data);
bit_offset += bits;
if (trits)
{
static const int bits_to_write[5] = { 2, 2, 1, 2, 1 };
static const int block_shift[5] = { 0, 2, 4, 5, 7 };
static const int next_lcounter[5] = { 1, 2, 3, 4, 0 };
static const int hcounter_incr[5] = { 0, 0, 0, 0, 1 };
write_bits(tq_blocks[hcounter] >> block_shift[lcounter], bits_to_write[lcounter], bit_offset, output_data);
bit_offset += bits_to_write[lcounter];
hcounter += hcounter_incr[lcounter];
lcounter = next_lcounter[lcounter];
}
if (quints)
{
static const int bits_to_write[3] = { 3, 2, 2 };
static const int block_shift[3] = { 0, 3, 5 };
static const int next_lcounter[3] = { 1, 2, 0 };
static const int hcounter_incr[3] = { 0, 0, 1 };
write_bits(tq_blocks[hcounter] >> block_shift[lcounter], bits_to_write[lcounter], bit_offset, output_data);
bit_offset += bits_to_write[lcounter];
hcounter += hcounter_incr[lcounter];
lcounter = next_lcounter[lcounter];
}
}
}
void decode_ise(int quantization_level, int elements, const uint8_t * input_data, uint8_t * output_data, int bit_offset)
{
int i;
// note: due to how the the trit/quint-block unpacking is done in this function,
// we may write more temporary results than the number of outputs
// The maximum actual number of results is 64 bit, but we keep 4 additional elements
// of padding.
uint8_t results[68];
uint8_t tq_blocks[22]; // trit-blocks or quint-blocks
int bits, trits, quints;
find_number_of_bits_trits_quints(quantization_level, &bits, &trits, &quints);
int lcounter = 0;
int hcounter = 0;
// trit-blocks or quint-blocks must be zeroed out before we collect them in the loop below.
for (i = 0; i < 22; i++)
tq_blocks[i] = 0;
// collect bits for each element, as well as bits for any trit-blocks and quint-blocks.
for (i = 0; i < elements; i++)
{
results[i] = read_bits(bits, bit_offset, input_data);
bit_offset += bits;
if (trits)
{
static const int bits_to_read[5] = { 2, 2, 1, 2, 1 };
static const int block_shift[5] = { 0, 2, 4, 5, 7 };
static const int next_lcounter[5] = { 1, 2, 3, 4, 0 };
static const int hcounter_incr[5] = { 0, 0, 0, 0, 1 };
int tdata = read_bits(bits_to_read[lcounter], bit_offset, input_data);
bit_offset += bits_to_read[lcounter];
tq_blocks[hcounter] |= tdata << block_shift[lcounter];
hcounter += hcounter_incr[lcounter];
lcounter = next_lcounter[lcounter];
}
if (quints)
{
static const int bits_to_read[3] = { 3, 2, 2 };
static const int block_shift[3] = { 0, 3, 5 };
static const int next_lcounter[3] = { 1, 2, 0 };
static const int hcounter_incr[3] = { 0, 0, 1 };
int tdata = read_bits(bits_to_read[lcounter], bit_offset, input_data);
bit_offset += bits_to_read[lcounter];
tq_blocks[hcounter] |= tdata << block_shift[lcounter];
hcounter += hcounter_incr[lcounter];
lcounter = next_lcounter[lcounter];
}
}
// unpack trit-blocks or quint-blocks as needed
if (trits)
{
int trit_blocks = (elements + 4) / 5;
for (i = 0; i < trit_blocks; i++)
{
const uint8_t *tritptr = trits_of_integer[tq_blocks[i]];
results[5 * i] |= tritptr[0] << bits;
results[5 * i + 1] |= tritptr[1] << bits;
results[5 * i + 2] |= tritptr[2] << bits;
results[5 * i + 3] |= tritptr[3] << bits;
results[5 * i + 4] |= tritptr[4] << bits;
}
}
if (quints)
{
int quint_blocks = (elements + 2) / 3;
for (i = 0; i < quint_blocks; i++)
{
const uint8_t *quintptr = quints_of_integer[tq_blocks[i]];
results[3 * i] |= quintptr[0] << bits;
results[3 * i + 1] |= quintptr[1] << bits;
results[3 * i + 2] |= quintptr[2] << bits;
}
}
for (i = 0; i < elements; i++)
output_data[i] = results[i];
}
int compute_ise_bitcount(int items, quantization_method quant)
{
switch (quant)
{
case QUANT_2:
return items;
case QUANT_3:
return (8 * items + 4) / 5;
case QUANT_4:
return 2 * items;
case QUANT_5:
return (7 * items + 2) / 3;
case QUANT_6:
return (13 * items + 4) / 5;
case QUANT_8:
return 3 * items;
case QUANT_10:
return (10 * items + 2) / 3;
case QUANT_12:
return (18 * items + 4) / 5;
case QUANT_16:
return items * 4;
case QUANT_20:
return (13 * items + 2) / 3;
case QUANT_24:
return (23 * items + 4) / 5;
case QUANT_32:
return 5 * items;
case QUANT_40:
return (16 * items + 2) / 3;
case QUANT_48:
return (28 * items + 4) / 5;
case QUANT_64:
return 6 * items;
case QUANT_80:
return (19 * items + 2) / 3;
case QUANT_96:
return (33 * items + 4) / 5;
case QUANT_128:
return 7 * items;
case QUANT_160:
return (22 * items + 2) / 3;
case QUANT_192:
return (38 * items + 4) / 5;
case QUANT_256:
return 8 * items;
default:
return 100000;
}
}