コード例 #1
0
        public static byte[] Decompress(Stream stream)
        {
            using (var br = new BinaryReader(stream, Encoding.Default, true))
            {
                int sizeAndMethod = br.ReadInt32();
                int size          = sizeAndMethod / 8;
                var method        = (Method)(sizeAndMethod % 8);

                switch (method)
                {
                case Method.NoCompression:
                    return(br.ReadBytes(size));

                case Method.LZ10:
                    return(LZ10.Decompress(br.BaseStream, size));

                case Method.Huffman4Bit:
                case Method.Huffman8Bit:
                    int num_bits = method == Method.Huffman4Bit ? 4 : 8;
                    return(Huffman.Decompress(br.BaseStream, num_bits, size, ByteOrder.LittleEndian));

                case Method.RLE:
                    return(RLE.Decompress(br.BaseStream, size));

                default:
                    throw new NotSupportedException($"Unknown compression method {method}");
                }
            }
        }
コード例 #2
0
        public static byte[] Compress(Stream stream, Method method)
        {
            if (stream.Length > 0x1fffffff)
            {
                throw new Exception("File is too big to be compressed with Level5 compressions!");
            }

            uint methodSize = (uint)stream.Length << 3;

            switch (method)
            {
            case Method.NoCompression:
                using (var bw = new BinaryWriterX(new MemoryStream()))
                {
                    bw.Write(methodSize);
                    stream.Position = 0;
                    stream.CopyTo(bw.BaseStream);
                    bw.BaseStream.Position = 0;
                    return(new BinaryReaderX(bw.BaseStream).ReadBytes((int)bw.BaseStream.Length));
                }

            case Method.LZ10:
                methodSize |= 0x1;
                using (var bw = new BinaryWriterX(new MemoryStream()))
                {
                    bw.Write(methodSize);
                    stream.Position = 0;
                    var comp = LZ10.Compress(stream);
                    bw.Write(comp);
                    bw.BaseStream.Position = 0;
                    return(new BinaryReaderX(bw.BaseStream).ReadBytes((int)bw.BaseStream.Length));
                }

            case Method.Huffman4Bit:
                methodSize |= 0x2;
                using (var bw = new BinaryWriterX(new MemoryStream()))
                {
                    bw.Write(methodSize);
                    stream.Position = 0;
                    var comp = Huffman.Compress(stream, 4);
                    bw.Write(comp);
                    bw.BaseStream.Position = 0;
                    return(new BinaryReaderX(bw.BaseStream).ReadBytes((int)bw.BaseStream.Length));
                }

            case Method.Huffman8Bit:
                methodSize |= 0x3;
                using (var bw = new BinaryWriterX(new MemoryStream()))
                {
                    bw.Write(methodSize);
                    stream.Position = 0;
                    var comp = Huffman.Compress(stream, 8);
                    bw.Write(comp);
                    bw.BaseStream.Position = 0;
                    return(new BinaryReaderX(bw.BaseStream).ReadBytes((int)bw.BaseStream.Length));
                }

            case Method.RLE:
                methodSize |= 0x4;
                using (var bw = new BinaryWriterX(new MemoryStream()))
                {
                    bw.Write(methodSize);
                    stream.Position = 0;
                    var comp = RLE.Compress(stream);
                    bw.Write(comp);
                    bw.BaseStream.Position = 0;
                    return(new BinaryReaderX(bw.BaseStream).ReadBytes((int)bw.BaseStream.Length));
                }

            default:
                throw new Exception($"Unsupported compression method {method}!");
            }
        }