01.03.2011 - as a initial commit

2011-03-01 06:07:16 +03:00
parent 3610ea9212
commit b21a0496cd
20 changed files with 1589 additions and 522 deletions
--- a/pibytearray.cpp
+++ b/pibytearray.cpp
@@ -0,0 +1,140 @@
+#include "pibytearray.h"
+
+
+int PIHuffman::nodeCompare(const void * f, const void * s) {
+	return (reinterpret_cast<node * >(const_cast<void * >(s))->freq -
+			reinterpret_cast<node * >(const_cast<void * >(f))->freq);
+}
+
+
+PIVector<uchar> PIHuffman::compress(const PIVector<uchar> & src) {
+	calcFrequencies(src);
+	return src;
+}
+
+
+void PIHuffman::calcFrequencies(const PIVector<uchar> & src) {
+	nodes.resize(256);
+	for (uint i = 0; i < 256; ++i) {
+		nodes[i].parent = nodes[i].right = nodes[i].left = 0;
+		nodes[i].freq = 0;
+		nodes[i].word.resize(1);
+		nodes[i].word[0] = static_cast<uchar>(i);
+	}
+	for (uint i = 0; i < src.size(); ++i)
+		nodes[src[i]].freq++;
+	std::qsort(nodes.data(), 256, sizeof(node), nodeCompare);
+	for (uint i = 255; i >= 0; --i)
+		if (nodes[i].freq > 0 && i < 255)
+			{nodes.remove(i + 1, 255 - i); break;}
+	for (uint i = 0; i < nodes.size(); ++i)
+		cout << string((char*)nodes[i].word.data(), 1) << ": " << nodes[i].freq << endl;
+}
+
+
+PIHuffman PIByteArray::huffman;
+
+PIByteArray & PIByteArray::convertToBase64() {
+	base64HelpStruct hs;
+	PIByteArray t;
+	if (size() == 0) return *this;
+	uint sz = (size() / 3) * 3;
+	for (uint i = 0; i < sz; ++i) {
+		hs.byte0 = hs.byte1 = hs.byte2 = 0;
+		hs.byte0 = at(i);
+		hs.byte1 = at(++i);
+		hs.byte2 = at(++i);
+		t.push_back(base64Table[hs.ascii0]);
+		t.push_back(base64Table[hs.ascii1]);
+		t.push_back(base64Table[hs.ascii2]);
+		t.push_back(base64Table[hs.ascii3]);
+	}
+	hs.byte0 = hs.byte1 = hs.byte2 = 0; sz = size() % 3;
+	switch (sz) {
+		case 1:
+			hs.byte0 = back();
+			t.push_back(base64Table[hs.ascii0]);
+			t.push_back(base64Table[hs.ascii1]);
+			t.push_back('=');
+			t.push_back('=');
+			break;
+		case 2:
+			hs.byte0 = at(size() - 2); hs.byte1 = back();
+			t.push_back(base64Table[hs.ascii0]);
+			t.push_back(base64Table[hs.ascii1]);
+			t.push_back(base64Table[hs.ascii2]);
+			t.push_back('=');
+			break;
+		default: break;
+	}
+	*this = t;
+	return *this;
+}
+
+
+PIByteArray & PIByteArray::convertFromBase64() {
+	base64HelpStruct hs;
+	PIByteArray t;
+	uint sz = size();
+	if (sz == 0) return *this;
+	for (uint i = 0; i < sz; ++i) {
+		hs.byte0 = hs.byte1 = hs.byte2 = 0;
+		hs.ascii0 = base64InvTable[at(i)];
+		hs.ascii1 = base64InvTable[at(++i)];
+		hs.ascii2 = base64InvTable[at(++i)];
+		hs.ascii3 = base64InvTable[at(++i)];
+		t.push_back(hs.byte0);
+		t.push_back(hs.byte1);
+		t.push_back(hs.byte2);
+	}
+	if (back() == '=') t.pop_back();
+		if (sz > 1) if (at(sz - 2) == '=') t.pop_back();
+	*this = t;
+	return *this;
+}
+
+
+PIByteArray & PIByteArray::compressRLE(uchar threshold) {
+	PIByteArray t;
+	uchar fb, clen, mlen = 255 - threshold;
+	for (uint i = 0; i < size();) {
+		fb = at(i);
+		clen = 1;
+		while (at(++i) == fb) {
+			++clen;
+			if (clen == mlen)
+				break;
+		}
+		if (clen > 1) {
+			t.push_back(threshold + clen);
+			t.push_back(fb);
+			continue;
+		}
+		if (fb >= threshold) {
+			t.push_back(threshold + 1);
+			t.push_back(fb);
+		} else
+			t.push_back(fb);
+	}
+	*this = t;
+	return *this;
+}
+
+
+PIByteArray & PIByteArray::decompressRLE(uchar threshold) {
+	PIByteArray t;
+	uchar fb, clen;
+	for (uint i = 0; i < size(); ++i) {
+		fb = at(i);
+		if (fb >= threshold) {
+			clen = fb - threshold;
+			fb = at(++i);
+			for (uint j = 0; j < clen; ++j)
+				t.push_back(fb);
+			continue;
+		} else
+			t.push_back(fb);
+	}
+	*this = t;
+	return *this;
+}