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QGIS/external/lazperf/decoder.hpp

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Embed a copy of laz-perf, and use if system laz-perf is not found Laz-perf is a relatively "underground" library, and is not packaged for many major distributions. Its also tiny and trivial to include with the other external libraries. This avoids requiring users who want point cloud support to have to compile their own laz-perf
2020-11-07 08:55:36 +10:00
/*
===============================================================================
FILE: decoder.hpp
CONTENTS:
Decoder stuff
PROGRAMMERS:
martin.isenburg@rapidlasso.com - http://rapidlasso.com
uday.karan@gmail.com - Hobu, Inc.
COPYRIGHT:
(c) 2007-2014, martin isenburg, rapidlasso - tools to catch reality
(c) 2014, Uday Verma, Hobu, Inc.
This is free software; you can redistribute and/or modify it under the
Update lazperf to post 3.0.0 to avoid already fixed warnings
2022-03-11 23:02:26 +01:00
terms of the Apache Public License 2.0 published by the Apache Software
Embed a copy of laz-perf, and use if system laz-perf is not found Laz-perf is a relatively "underground" library, and is not packaged for many major distributions. Its also tiny and trivial to include with the other external libraries. This avoids requiring users who want point cloud support to have to compile their own laz-perf
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Foundation. See the COPYING file for more information.
This software is distributed WITHOUT ANY WARRANTY and without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
CHANGE HISTORY:
Update lazperf to post 3.0.0 to avoid already fixed warnings
2022-03-11 23:02:26 +01:00
see header file
Embed a copy of laz-perf, and use if system laz-perf is not found Laz-perf is a relatively "underground" library, and is not packaged for many major distributions. Its also tiny and trivial to include with the other external libraries. This avoids requiring users who want point cloud support to have to compile their own laz-perf
2020-11-07 08:55:36 +10:00
===============================================================================
*/
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// -
// **************************** -
// ARITHMETIC CODING EXAMPLES -
// **************************** -
// -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// -
// Fast arithmetic coding implementation -
// -> 32-bit variables, 32-bit product, periodic updates, table decoding -
// -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// -
// Version 1.00 - April 25, 2004 -
// -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// -
// WARNING -
// ========= -
// -
// The only purpose of this program is to demonstrate the basic principles -
// of arithmetic coding. The original version of this code can be found in -
// Digital Signal Compression: Principles and Practice -
// (Cambridge University Press, 2011, ISBN: 9780511984655) -
// -
// Copyright (c) 2019 by Amir Said (said@ieee.org) & -
// William A. Pearlman (pearlw@ecse.rpi.edu) -
// -
// Redistribution and use in source and binary forms, with or without -
// modification, are permitted provided that the following conditions are -
// met: -
// -
// 1. Redistributions of source code must retain the above copyright notice, -
// this list of conditions and the following disclaimer. -
// -
// 2. Redistributions in binary form must reproduce the above copyright -
// notice, this list of conditions and the following disclaimer in the -
// documentation and/or other materials provided with the distribution. -
// -
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED -
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A -
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER -
// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, -
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, -
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR -
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF -
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING -
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS -
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -
// -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// -
// A description of the arithmetic coding method used here is available in -
// -
// Lossless Compression Handbook, ed. K. Sayood -
// Chapter 5: Arithmetic Coding (A. Said), pp. 101-152, Academic Press, 2003 -
// -
// A. Said, Introduction to Arithetic Coding Theory and Practice -
// HP Labs report HPL-2004-76 - http://www.hpl.hp.com/techreports/ -
// -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#ifndef __decoder_hpp__
#define __decoder_hpp__
#include <cassert>
Switch to laz-perf 3.0.0 It is not a header-only library anymore, so we also look for LazPerf_LIBRARY now and if using embedded laz-perf, there are few cpp files to compile.
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#include <memory>
#include "coderbase.hpp"
namespace lazperf
{
namespace decoders
{
template<typename TInputStream>
struct arithmetic
{
public:
arithmetic(TInputStream& in) : instream(in)
{
init();
}
arithmetic() : pIn(new TInputStream()), instream(*pIn)
{
init();
}
arithmetic(const arithmetic<TInputStream>& src) :
pIn(new TInputStream(*src.pIn)), instream(*pIn)
{
value = src.value;
length = src.length;
}
~arithmetic() {
}
template <typename TSrcStream>
void initStream(TSrcStream& src, uint32_t cnt)
{
if (cnt)
{
instream.copy(src, cnt);
readInitBytes();
hasData = true;
}
}
void readInitBytes()
{
value =
(instream.getByte() << 24) |
(instream.getByte() << 16) |
(instream.getByte() << 8) |
instream.getByte();
}
template<typename TEntropyModel>
uint32_t decodeBit(TEntropyModel& m)
{
uint32_t x = m.bit_0_prob * (length >> BM__LengthShift); // product l x p0
uint32_t sym = (value >= x); // decision
// update & shift interval
if (sym == 0)
{
length = x;
++m.bit_0_count;
}
else
{
value -= x; // shifted interval base = 0
length -= x;
}
if (length < AC__MinLength)
renorm_dec_interval(); // renormalization
if (--m.bits_until_update == 0)
m.update(); // periodic model update
return sym; // return data bit value
}
template<typename TEntropyModel>
uint32_t decodeSymbol(TEntropyModel& m)
{
uint32_t n, sym, x, y = length;
if (m.decoder_table) // use table look-up for faster decoding
{
unsigned dv = value / (length >>= DM__LengthShift);
unsigned t = dv >> m.table_shift;
sym = m.decoder_table[t]; // initial decision based on table look-up
n = m.decoder_table[t+1] + 1;
while (n > sym + 1) // finish with bisection search
{
uint32_t k = (sym + n) >> 1;
if (m.distribution[k] > dv)
n = k;
else
sym = k;
}
// compute products
x = m.distribution[sym] * length;
if (sym != m.last_symbol)
y = m.distribution[sym+1] * length;
}
else // decode using only multiplications
{
x = sym = 0;
length >>= DM__LengthShift;
uint32_t k = (n = m.symbols) >> 1;
// decode via bisection search
do {
uint32_t z = length * m.distribution[k];
if (z > value)
{
n = k;
y = z; // value is smaller
}
else
{
sym = k;
x = z; // value is larger or equal
}
} while ((k = (sym + n) >> 1) != sym);
}
value -= x; // update interval
length = y - x;
// renormalization
if (length < AC__MinLength)
renorm_dec_interval();
++m.symbol_count[sym];
// periodic model update
if (--m.symbols_until_update == 0)
m.update();
return sym;
}
uint32_t readBit()
{
uint32_t sym = value / (length >>= 1); // decode symbol, change length
value -= length * sym; // update interval
if (length < AC__MinLength)
renorm_dec_interval(); // renormalization
return sym;
}
uint32_t readBits(uint32_t bits)
{
assert(bits && (bits <= 32));
if (bits > 19)
{
uint32_t tmp = readShort();
bits = bits - 16;
uint32_t tmp1 = readBits(bits) << 16;
return (tmp1 | tmp);
}
uint32_t sym = value / (length >>= bits);// decode symbol, change length
value -= length * sym; // update interval
if (length < AC__MinLength)
renorm_dec_interval(); // renormalization
return sym;
}
uint8_t readByte()
{
uint32_t sym = value / (length >>= 8); // decode symbol, change length
value -= length * sym; // update interval
if (length < AC__MinLength)
renorm_dec_interval(); // renormalization
assert(sym < (1 << 8));
return (uint8_t)sym;
}
uint16_t readShort()
{
uint32_t sym = value / (length >>= 16); // decode symbol, change length
value -= length * sym; // update interval
if (length < AC__MinLength)
renorm_dec_interval(); // renormalization
assert(sym < (1<<16));
return (uint16_t)sym;
}
uint32_t readInt()
{
uint32_t lowerInt = readShort();
uint32_t upperInt = readShort();
return (upperInt<<16)|lowerInt;
}
/* danger in float reinterpretation */
float readFloat()
{
U32I32F32 u32i32f32;
u32i32f32.u32 = readInt();
return u32i32f32.f32;
}
uint64_t readInt64()
{
uint64_t lowerInt = readInt();
uint64_t upperInt = readInt();
return (upperInt<<32)|lowerInt;
}
/* danger in float reinterpretation */
double readDouble()
{
U64I64F64 u64i64f64;
u64i64f64.u64 = readInt64();
return u64i64f64.f64;
}
TInputStream& getInStream()
{
return instream;
}
bool valid() const
{
return hasData;
}
arithmetic<TInputStream>& operator = (const arithmetic<TInputStream>&) = delete;
private:
void init()
{
value = 0;
length = AC__MaxLength;
hasData = false;
}
void renorm_dec_interval()
{
do { // read least-significant byte
value = (value << 8) | instream.getByte();
} while ((length <<= 8) < AC__MinLength); // length multiplied by 256
}
uint32_t value;
uint32_t length;
bool hasData;
std::unique_ptr<TInputStream> pIn;
TInputStream& instream;
};
} // namespace decoders
} // namespace lazperf
Embed a copy of laz-perf, and use if system laz-perf is not found Laz-perf is a relatively "underground" library, and is not packaged for many major distributions. Its also tiny and trivial to include with the other external libraries. This avoids requiring users who want point cloud support to have to compile their own laz-perf
2020-11-07 08:55:36 +10:00
#endif // __decoder_hpp__
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