source: thirdparty/SZ/sz/src/szd_double_ts.c @ 2c47b73

/**
 *  @file szd_double_ts.c
 *  @author Sheng Di and Dingwen Tao
 *  @date Aug, 2016
 *  @brief 
 *  (C) 2016 by Mathematics and Computer Science (MCS), Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

#include <stdlib.h> 
#include <stdio.h>
#include <string.h>
#include "szd_double.h"
#include "TightDataPointStorageD.h"
#include "sz.h"
#include "Huffman.h"
#include "szd_double_ts.h"

void decompressDataSeries_double_1D_ts(double** data, size_t dataSeriesLength, sz_multisteps* multisteps, TightDataPointStorageD* tdps) 
{
        double* lastSnapshotData = (double*)multisteps->hist_data;
        updateQuantizationInfo(tdps->intervals);
        size_t i, j, k = 0, p = 0, l = 0; // k is to track the location of residual_bit
                                                                // in resiMidBits, p is to track the
                                                                // byte_index of resiMidBits, l is for
                                                                // leadNum
        unsigned char* leadNum;
        double interval = tdps->realPrecision*2;
        
        convertByteArray2IntArray_fast_2b(tdps->exactDataNum, tdps->leadNumArray, tdps->leadNumArray_size, &leadNum);
        *data = (double*)malloc(sizeof(double)*dataSeriesLength);

        int* type = (int*)malloc(dataSeriesLength*sizeof(int));
        
        HuffmanTree* huffmanTree = createHuffmanTree(tdps->stateNum);
        decode_withTree(huffmanTree, tdps->typeArray, dataSeriesLength, type);
        SZ_ReleaseHuffman(huffmanTree); 

        unsigned char preBytes[8];
        unsigned char curBytes[8];
        
        memset(preBytes, 0, 8);

        size_t curByteIndex = 0;
        int reqBytesLength, resiBitsLength, resiBits; 
        unsigned char leadingNum;       
        double medianValue, exactData, predValue = 0;
        
        reqBytesLength = tdps->reqLength/8;
        resiBitsLength = tdps->reqLength%8;
        medianValue = tdps->medianValue;
        
        int type_;
        for (i = 0; i < dataSeriesLength; i++) {
                type_ = type[i];
                switch (type_) {
                case 0:
                        // compute resiBits
                        resiBits = 0;
                        if (resiBitsLength != 0) {
                                int kMod8 = k % 8;
                                int rightMovSteps = getRightMovingSteps(kMod8, resiBitsLength);
                                if (rightMovSteps > 0) {
                                        int code = getRightMovingCode(kMod8, resiBitsLength);
                                        resiBits = (tdps->residualMidBits[p] & code) >> rightMovSteps;
                                } else if (rightMovSteps < 0) {
                                        int code1 = getLeftMovingCode(kMod8);
                                        int code2 = getRightMovingCode(kMod8, resiBitsLength);
                                        int leftMovSteps = -rightMovSteps;
                                        rightMovSteps = 8 - leftMovSteps;
                                        resiBits = (tdps->residualMidBits[p] & code1) << leftMovSteps;
                                        p++;
                                        resiBits = resiBits
                                                        | ((tdps->residualMidBits[p] & code2) >> rightMovSteps);
                                } else // rightMovSteps == 0
                                {
                                        int code = getRightMovingCode(kMod8, resiBitsLength);
                                        resiBits = (tdps->residualMidBits[p] & code);
                                        p++;
                                }
                                k += resiBitsLength;
                        }

                        // recover the exact data
                        memset(curBytes, 0, 8);
                        leadingNum = leadNum[l++];
                        memcpy(curBytes, preBytes, leadingNum);
                        for (j = leadingNum; j < reqBytesLength; j++)
                                curBytes[j] = tdps->exactMidBytes[curByteIndex++];
                        if (resiBitsLength != 0) {
                                unsigned char resiByte = (unsigned char) (resiBits << (8 - resiBitsLength));
                                curBytes[reqBytesLength] = resiByte;
                        }
                        
                        exactData = bytesToDouble(curBytes);
                        (*data)[i] = exactData + medianValue;
                        memcpy(preBytes,curBytes,8);
                        break;
                default:
                        //predValue = (*data)[i-1];
                        if(confparams_dec->szMode == SZ_TEMPORAL_COMPRESSION)
                                predValue = lastSnapshotData[i];
                        (*data)[i] = predValue + (type_-exe_params->intvRadius)*interval;
                        break;
                }
                //printf("%.30G\n",(*data)[i]);
        }
        
        memcpy(multisteps->hist_data, (*data), dataSeriesLength*sizeof(double));
        
        free(leadNum);
        free(type);
        return;
}