Esempio n. 1
0
        public static IEnumerable <Image> ParseImagesFromSwfFile(Stream stream)
        {
            using (stream)
            {
                using var reader = new BittableBinaryReader(stream);

                var header = Encoding.ASCII.GetString(reader.ReadBytes(3));
                if (header == "ZWS")
                {
                    throw new InvalidOperationException($"Unspported file type '{header}'.");
                }
                else if (header != "CWS" && header != "FWS")
                {
                    throw new InvalidDataException("Not a valid SWF file.");
                }

                var versionNumber = reader.ReadByte();
                var fileLength    = reader.ReadInt32(); //This is the uncompressed length, so won't match file size for CWF

                if (header == "CWS")
                {
                    //CWS Files are compressed with Zlib
                    reader.ReadBytes(2); //Skip the zlib header, since DeflateStream won't process it correctly
                    using var compressedReader = new BittableBinaryReader(new DeflateStream(reader.BaseStream, CompressionMode.Decompress));
                    return(ReadHeaderAndImages(compressedReader));
                }
                return(ReadHeaderAndImages(reader));
            }
        }
Esempio n. 2
0
        private static List <SwfTag> ReadTags(BittableBinaryReader reader)
        {
            var tags = new List <SwfTag>();

            do
            {
                tags.Add(ReadTag(reader));
            } while (tags[tags.Count - 1].Code != SwfTagCode.End);
            return(tags);
        }
Esempio n. 3
0
        private static void ReadRect(BittableBinaryReader reader)
        {
            //This is the "twip" sized boundaries of the SWF
            int length = reader.ReadBits(5); //Bit length of bounds

            _ = reader.ReadBits(length);     //xMin
            _ = reader.ReadBits(length);     //xMax
            _ = reader.ReadBits(length);     //yMin
            _ = reader.ReadBits(length);     //yMax
        }
Esempio n. 4
0
        private static IEnumerable <Image> ReadHeaderAndImages(BittableBinaryReader reader)
        {
            ReadRect(reader);
            var framerate  = reader.ReadInt16();
            var frameCount = reader.ReadInt16();

            var tags = ReadTags(reader);

            return(tags.Where(t => IMAGE_CODES.Contains(t.Code)).Select(t => HandleImageTag(t)));
        }
Esempio n. 5
0
        private static SwfTag ReadTag(BittableBinaryReader reader)
        {
            uint tagCodeAndLength = reader.ReadUInt16();
            uint code             = (tagCodeAndLength & 0b1111_1111_1100_0000) >> 6; //upper 10 bits are code
            uint length           = tagCodeAndLength & 0b0011_1111;                  //lower 6 bits are length

            if (length == 0b0011_1111)
            {
                //If all length bits are set, this is a large block and uses a UInt to signal size
                length = reader.ReadUInt32();
            }
            var data = reader.ReadBytes((int)length); //This cast isn't safe, probably should check this

            return(new SwfTag()
            {
                Code = (SwfTagCode)code, Data = data
            });
        }