From 5cc4256a931b98ea167291397421d0db60c5d40c Mon Sep 17 00:00:00 2001 From: pacien Date: Sun, 2 Dec 2018 00:22:56 +0100 Subject: implement lzss block --- tests/tlzss.nim | 9 ---- tests/tlzsshuffman.nim | 144 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 144 insertions(+), 9 deletions(-) create mode 100644 tests/tlzsshuffman.nim (limited to 'tests') diff --git a/tests/tlzss.nim b/tests/tlzss.nim index 7325d5b..b6b3c51 100644 --- a/tests/tlzss.nim +++ b/tests/tlzss.nim @@ -66,15 +66,6 @@ suite "lzsschain": test "decode": check chain().decode() == @[0'u8, 1, 2, 3, 4, 5, 0, 1, 2, 3, 0, 1, 4, 5, 0, 5, 5, 0, 5, 5] - test "stats": - let stats = chain().stats() - check stats.characters == newCountTable(concat( - repeat(0'u8, 2), repeat(1'u8, 2), repeat(2'u8, 1), repeat(3'u8, 1), repeat(4'u8, 1), repeat(5'u8, 3))) - check stats.lengths == newCountTable(concat( - repeat(3, 2), repeat(4, 1))) - check stats.positions == newCountTable(concat( - repeat(3, 1), repeat(6, 1), repeat(8, 1))) - suite "lzssencoder": test "commonPrefixLength": check commonPrefixLength([], [], 0, 10) == 0 diff --git a/tests/tlzsshuffman.nim b/tests/tlzsshuffman.nim new file mode 100644 index 0000000..f771f31 --- /dev/null +++ b/tests/tlzsshuffman.nim @@ -0,0 +1,144 @@ +# gzip-like LZSS compressor +# Copyright (C) 2018 Pacien TRAN-GIRARD +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as +# published by the Free Software Foundation, either version 3 of the +# License, or (at your option) any later version. +# +# This program 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 Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see . + +import unittest, tables, lists, sequtils, streams +import bitio/bitwriter, bitio/bitreader +import lzss/listpolyfill, lzss/lzssnode, lzss/lzsschain +import huffman/huffmantree, huffman/huffmantreebuilder, huffman/huffmanencoder, huffman/huffmandecoder +import lzsshuffman/lzsshuffmansymbol, lzsshuffman/lzsshuffmanstats, lzsshuffman/lzsshuffmanencoder, lzsshuffman/lzsshuffmandecoder + +suite "lzsshuffmansymbol": + test "isEndMarker": + check 'a'.Symbol.isEndMarker() == false + check endSymbol.isEndMarker() + + test "isCharacter": + check 'a'.Symbol.isCharacter() + check endSymbol.isCharacter() == false + check 300.Symbol.isCharacter() == false + + test "unpackLzssReference": + check unpackLzssReference(257.Symbol, 10) == lzssReference(3, 10) + check unpackLzssReference(300.Symbol, 10) == lzssReference(46, 10) + + test "shiftLzssLength": + check shiftLzssLength(3) == 257'u16 + check shiftLzssLength(10) == 264'u16 + +suite "lzsshuffmanstats": + test "aggretateStats": + let chain = lzssChain([ + lzssCharacter(0), lzssCharacter(1), lzssCharacter(2), + lzssCharacter(3), lzssCharacter(4), lzssCharacter(5), + lzssReference(4, 6), lzssCharacter(0), lzssCharacter(1), + lzssReference(3, 8), lzssCharacter(5), + lzssReference(3, 3), lzssCharacter(5)]) + let (symbolTable, positionTable) = chain.aggregateStats() + check symbolTable == newCountTable(concat( + repeat(0'u16, 2), repeat(1'u16, 2), repeat(2'u16, 1), repeat(3'u16, 1), repeat(4'u16, 1), repeat(5'u16, 3), + repeat(endSymbol.uint16, 1), + repeat(257'u16, 2), repeat(258'u16, 1))) + check positionTable == newCountTable(concat( + repeat(3'u16, 1), repeat(6'u16, 1), repeat(8'u16, 1))) + +suite "lzsshuffmanencoder": + test "writeChain (empty)": + let chain = lzssChain(newSeq[LzssNode]()) + let symbolTree = huffmanLeaf(endSymbol.uint16) + let positionTree = huffmanLeaf(0'u16) + let stream = newStringStream() + defer: stream.close() + let bitWriter = stream.bitWriter() + writeChain(chain, symbolTree.encoder(uint16), positionTree.encoder(uint16), bitWriter) + bitWriter.flush() + stream.setPosition(0) + check stream.atEnd() + + test "writeChain (minimal)": + let chain = lzssChain([ + lzssCharacter(0), lzssCharacter(1), lzssCharacter(2), + lzssReference(3, 3), lzssReference(3, 4)]) + let symbolTree = huffmanBranch( + huffmanBranch( + huffmanLeaf(0'u16), + huffmanLeaf(1'u16)), + huffmanBranch( + huffmanLeaf(257'u16), + huffmanBranch( + huffmanLeaf(2'u16), + huffmanLeaf(256'u16)))) + let positionTree = huffmanBranch( + huffmanLeaf(3'u16), + huffmanLeaf(4'u16)) + let stream = newStringStream() + defer: stream.close() + let bitWriter = stream.bitWriter() + writeChain(chain, symbolTree.encoder(uint16), positionTree.encoder(uint16), bitWriter) + bitWriter.flush() + stream.setPosition(0) + let bitReader = stream.bitReader() + check bitReader.readBits(2, uint8) == 0b00'u8 # char 0 + check bitReader.readBits(2, uint8) == 0b10'u8 # char 1 + check bitReader.readBits(3, uint8) == 0b011'u8 # char 2 + check bitReader.readBits(2, uint8) == 0b01'u8 # ref len 3 + check bitReader.readBits(1, uint8) == 0b0'u8 # ref pos 3 + check bitReader.readBits(2, uint8) == 0b01'u8 # ref len 3 + check bitReader.readBits(1, uint8) == 0b1'u8 # ref pos 4 + check bitReader.readBits(3, uint8) == 0b111'u8 # eof + +suite "lzsshuffmandecoder": + test "readChain (empty)": + let symbolTree = huffmanLeaf(endSymbol.uint16) + let positionTree = huffmanLeaf(0'u16) + let stream = newStringStream() + defer: stream.close() + stream.write(0'u8) # eof + stream.setPosition(0) + let bitReader = stream.bitReader() + let result = readChain(bitReader, symbolTree.decoder(), positionTree.decoder(), 32_000) + check toSeq(result.items).len == 0 + + test "readChain (minimal)": + let symbolTree = huffmanBranch( + huffmanBranch( + huffmanLeaf(0'u16), + huffmanLeaf(1'u16)), + huffmanBranch( + huffmanLeaf(257'u16), + huffmanBranch( + huffmanLeaf(2'u16), + huffmanLeaf(256'u16)))) + let positionTree = huffmanBranch( + huffmanLeaf(3'u16), + huffmanLeaf(4'u16)) + let stream = newStringStream() + defer: stream.close() + let bitWriter = stream.bitWriter() + bitWriter.writeBits(2, 0b00'u8) + bitWriter.writeBits(2, 0b10'u8) + bitWriter.writeBits(3, 0b011'u8) + bitWriter.writeBits(2, 0b01'u8) + bitWriter.writeBits(1, 0b0'u8) + bitWriter.writeBits(2, 0b01'u8) + bitWriter.writeBits(1, 0b1'u8) + bitWriter.writeBits(3, 0b111'u8) + bitWriter.flush() + stream.setPosition(0) + let bitReader = stream.bitReader() + let result = readChain(bitReader, symbolTree.decoder(), positionTree.decoder(), 32_000) + check toSeq(result.items) == [ + lzssCharacter(0), lzssCharacter(1), lzssCharacter(2), + lzssReference(3, 3), lzssReference(3, 4)] -- cgit v1.2.3