/*
* libopenraw - olympusdecompressor.cpp
*
* Copyright (C) 2011-2016 Hubert Figuiere
* Olympus Decompression copied from RawSpeed
* Copyright (C) 2009 Klaus Post
*
* This library is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <string.h>
#include <algorithm>
#include "rawdata.hpp"
#include "olympusdecompressor.hpp"
#include "bititerator.hpp"
namespace OpenRaw {
namespace Internals {
static void decompressOlympus(const uint8_t* buffer, size_t size, uint8_t* data,
uint32_t w, uint32_t h);
// decompression ported from RawSpeed.
static void decompressOlympus(const uint8_t* buffer, size_t size, uint8_t* data,
uint32_t w, uint32_t h)
{
int nbits, sign, low, high, i, wo0, n, nw0, wo1, nw1;
int acarry0[3], acarry1[3], pred, diff;
int pitch = w * 2; //(((w * 2/*bpp*/) + 15) / 16) * 16; // TODO make that
//part of the outer datas
/* Build a table to quickly look up "high" value */
char bittable[4096];
for (i = 0; i < 4096; i++) {
int b = i;
for (high = 0; high < 12; high++) {
if ((b >> (11 - high)) & 1) {
break;
}
}
bittable[i] = high;
}
wo0 = nw0 = wo1 = nw1 = 0;
buffer += 7;
BitIterator bits(buffer, size - 7);
for (uint32_t y = 0; y < h; y++) {
memset(acarry0, 0, sizeof acarry0);
memset(acarry1, 0, sizeof acarry1);
uint16_t* dest = (uint16_t*)&data[y * pitch];
for (uint32_t x = 0; x < w; x++) {
// bits.checkPos();
// bits.fill();
i = 2 * (acarry0[2] < 3);
for (nbits = 2 + i; (uint16_t)acarry0[0] >> (nbits + i); nbits++) {
}
uint32_t b = bits.peek(15);
sign = (b >> 14) * -1;
low = (b >> 12) & 3;
high = bittable[b & 4095];
// Skip bits used above.
bits.skip(std::min(12 + 3, high + 1 + 3));
if (high == 12) {
high = bits.get(16 - nbits) >> 1;
}
acarry0[0] = (high << nbits) | bits.get(nbits);
diff = (acarry0[0] ^ sign) + acarry0[1];
acarry0[1] = (diff * 3 + acarry0[1]) >> 5;
acarry0[2] = acarry0[0] > 16 ? 0 : acarry0[2] + 1;
if (y < 2 || x < 2) {
if (y < 2 && x < 2) {
pred = 0;
} else if (y < 2) {
pred = wo0;
} else {
pred = dest[-pitch + ((int)x)];
nw0 = pred;
}
dest[x] = pred + ((diff << 2) | low);
// Set predictor
wo0 = dest[x];
} else {
n = dest[-pitch + ((int)x)];
if (((wo0 < nw0) & (nw0 < n)) | ((n < nw0) & (nw0 < wo0))) {
if (abs(wo0 - nw0) > 32 || abs(n - nw0) > 32) {
pred = wo0 + n - nw0;
} else {
pred = (wo0 + n) >> 1;
}
} else {
pred = abs(wo0 - nw0) > abs(n - nw0) ? wo0 : n;
}
dest[x] = pred + ((diff << 2) | low);
// Set predictors
wo0 = dest[x];
nw0 = n;
}
// _ASSERTE(0 == dest[x] >> 12) ;
// ODD PIXELS
x += 1;
// bits.checkPos();
// bits.fill();
i = 2 * (acarry1[2] < 3);
for (nbits = 2 + i; (uint16_t)acarry1[0] >> (nbits + i); nbits++) {
}
b = bits.peek(15);
sign = (b >> 14) * -1;
low = (b >> 12) & 3;
high = bittable[b & 4095];
// Skip bits used above.
bits.skip(std::min(12 + 3, high + 1 + 3));
if (high == 12) {
high = bits.get(16 - nbits) >> 1;
}
acarry1[0] = (high << nbits) | bits.get(nbits);
diff = (acarry1[0] ^ sign) + acarry1[1];
acarry1[1] = (diff * 3 + acarry1[1]) >> 5;
acarry1[2] = acarry1[0] > 16 ? 0 : acarry1[2] + 1;
if (y < 2 || x < 2) {
if (y < 2 && x < 2) {
pred = 0;
} else if (y < 2) {
pred = wo1;
} else {
pred = dest[-pitch + ((int)x)];
nw1 = pred;
}
dest[x] = pred + ((diff << 2) | low);
// Set predictor
wo1 = dest[x];
} else {
n = dest[-pitch + ((int)x)];
if (((wo1 < nw1) & (nw1 < n)) | ((n < nw1) & (nw1 < wo1))) {
if (abs(wo1 - nw1) > 32 || abs(n - nw1) > 32) {
pred = wo1 + n - nw1;
} else {
pred = (wo1 + n) >> 1;
}
} else {
pred = abs(wo1 - nw1) > abs(n - nw1) ? wo1 : n;
}
dest[x] = pred + ((diff << 2) | low);
// Set predictors
wo1 = dest[x];
nw1 = n;
}
// _ASSERTE(0 == dest[x] >> 12) ;
}
}
}
RawDataPtr OlympusDecompressor::decompress()
{
RawDataPtr output(new RawData);
output->allocData(m_w * m_h * 2);
decompressOlympus(m_buffer, m_size, (uint8_t*)output->data(), m_w, m_h);
// hardcoded 12bits values
output->setBpc(12);
output->setWhiteLevel((1 << 12) - 1);
return output;
}
}
}