/**
* decompress the data with stack-ZDPD algorithm
*
* @param layers compressed mzArray
* @return decompressed mzArray
*/
public static List <int[]> stackDecode(Layers layers)
{
int[] stackArr = CompressUtil.fastPforDecoder(CompressUtil.byteToInt(CompressUtil.zlibDecoder(layers.mzArray)));
int[] stackIndex = new int[stackArr.Length];
byte[] tagShift = CompressUtil.zlibDecoder(layers.tagArray);
int digit = layers.digit;
//拆分byte为8个bit，并分别存储
byte[] value = new byte[8 * tagShift.Length];
for (int i = 0; i < tagShift.Length; i++)
{
for (int j = 0; j < 8; j++)
{
value[8 * i + j] = (byte)(((tagShift[i] & 0xff) >> j) & 1);
}
}
//还原为int类型的index
for (int i = 0; i < stackIndex.Length; i++)
{
for (int j = 0; j < digit; j++)
{
stackIndex[i] += value[digit * i + j] << j;
}
}
//统计index数组中各个元素出现的次数
Hashtable table = new Hashtable();
foreach (int index in stackIndex)
{
if (table.ContainsKey(index))
{
table[index] = (int)table[index] + 1;
}
else
{
table[index] = 1;
}
}
//根据index拆分stackArr,还原数组
List <int[]> arrGroup = new List <int[]>();
int arrNum = table.Keys.Count;
for (int i = 0; i < arrNum; i++)
{
arrGroup.Add(new int[(int)table[i]]);
}
int[] p = new int[arrNum];
for (int i = 0; i < stackIndex.Length; i++)
{
arrGroup[stackIndex[i]][p[stackIndex[i]]++] = stackArr[i];
}
return(arrGroup);
}
/**
* compress the data with stack-ZDPD algorithm
*
* @param arrGroup mzArray to be compressed
* @param pair sorting method of mzArray
* @return compressed mzArray
*/
public static Layers stackEncode(List <int[]> arrGroup, Boolean pair)
{
int stackLen = 0; //记录堆叠数总长度
foreach (int[] arr in arrGroup)
{
stackLen += arr.Length;
}
//合并排序数组 pair：默认采取pair成对排序，True也采取pair排序；false时采用QueueSort
int[,] stackSort;
stackSort = getPairSortArray(arrGroup);
//if (pair)
//{
// stackSort = getPairSortArray(arrGroup);
//}
//else
//{
// stackSort = getQueueSortArray(arrGroup);
//}
//取出stack数组和index数组
int[] stackArr = new int[stackLen];
int[] stackIndex = new int[stackLen];
for (int i = 0; i < stackLen; i++)
{
stackArr[i] = stackSort[i, 0];
stackIndex[i] = stackSort[i, 1];
}
//index移位存储
int digit = (int)Math.Ceiling(Math.Log(arrGroup.Count) / Math.Log(2));
int indexLen = (stackLen * digit - 1) / 8 + 1;
byte[] value = new byte[8 * indexLen];
for (int i = 0; i < stackLen; i++)
{
int fromIndex = digit * i;
for (int j = 0; j < digit; j++)
{
value[fromIndex + j] = (byte)((stackIndex[i] >> j) & 1);
}
}
//把8个byte并为1个byte，用byte数组存是因为zlib压缩的是byte
byte[] indexShift = new byte[indexLen];
for (int i = 0; i < indexLen; i++)
{
int temp = 0;
for (int j = 0; j < 8; j++)
{
temp += value[8 * i + j] << j;
indexShift[i] = (byte)temp;
}
}
//数组用fastPFor压缩，index用zlib压缩，并记录层数
Layers layers = new Layers();
layers.mzArray = CompressUtil.zlibEncoder(CompressUtil.intToByte(CompressUtil.fastPforEncoder(stackArr)));
layers.tagArray = CompressUtil.zlibEncoder(indexShift);
layers.digit = digit;
return(layers);
}
