Exemplo n.º 1
0
        /// <summary>
        /// Extracts various fields specific to this chunk from the APNG's
        /// data field
        /// </summary>
        /// <param name="chunkData">An array of bytes representing the APNG's data field</param>
        protected override void ParseData(byte[] chunkData)
        {
            int offset = 0;

            frameWidth  = APNGUtility.ParseUint(chunkData, 4, ref offset);
            frameHeight = APNGUtility.ParseUint(chunkData, 4, ref offset);
            //ticksPerSecond = APNGUtility.ParseUint(chunkData, 4, ref offset);
            //nominalLayerCount = APNGUtility.ParseUint(chunkData, 4, ref offset);
            //nominalFrameCount = APNGUtility.ParseUint(chunkData, 4, ref offset);
            //nominalPlayTime = APNGUtility.ParseUint(chunkData, 4, ref offset);
            //simplicityProfile = APNGUtility.ParseUint(chunkData, 4, ref offset);
        }
Exemplo n.º 2
0
        /// <summary>
        /// Extracts various fields specific to this chunk from the APNG's
        /// data field
        /// </summary>
        /// <param name="chunkData">An array of bytes representing the APNG's data field</param>
        protected override void ParseData(byte[] chunkData)
        {
            int offset = 0;

            width             = APNGUtility.ParseUint(chunkData, 4, ref offset);
            height            = APNGUtility.ParseUint(chunkData, 4, ref offset);
            bitDepth          = APNGUtility.ParseUint(chunkData, 1, ref offset);
            colorType         = APNGUtility.ParseUint(chunkData, 1, ref offset);
            compressionMethod = APNGUtility.ParseUint(chunkData, 1, ref offset);
            filterMethod      = APNGUtility.ParseUint(chunkData, 1, ref offset);
            interlaceMethod   = APNGUtility.ParseUint(chunkData, 1, ref offset);
        }
Exemplo n.º 3
0
        /// <summary>
        /// Extracts various fields specific to this chunk from the APNG's
        /// data field
        /// </summary>
        /// <param name="chunkData">An array of bytes representing the APNG's data field</param>
        protected override void ParseData(byte[] chunkData)
        {
            int offset = 0;

            terminationAction = APNGUtility.ParseUint(chunkData, 1, ref offset);
            // If the data length is > 1 then read 9 more bytes
            if (chunkData.Length > 1)
            {
                actionAfterTermination = APNGUtility.ParseUint(chunkData, 1, ref offset);
                delay        = APNGUtility.ParseUint(chunkData, 4, ref offset);
                iterationMax = APNGUtility.ParseUint(chunkData, 4, ref offset);
            }
        }
Exemplo n.º 4
0
        /// <summary>
        /// Attempts to parse an APNGChunk for the specified stream
        /// </summary>
        /// <param name="stream">The stream containing the APNG Chunk</param>
        public void Read(Stream stream)
        {
            if (!stream.CanRead)
            {
                throw new ArgumentException("Stream is not readable");
            }

            calculatedCRC = CRC.INITIAL_CRC;

            long chunkStart = stream.Position;

            // Read the data Length
            chunkLength = APNGUtility.ReadStream(stream, 4);

            // Read the chunk type
            chunkType     = APNGUtility.ReadStream(stream, 4);
            calculatedCRC = CRC.UpdateCRC(calculatedCRC, chunkType);

            // Read the data
            chunkData     = APNGUtility.ReadStream(stream, ChunkLength);
            calculatedCRC = CRC.UpdateCRC(calculatedCRC, chunkData);

            // Read the CRC
            chunkCRC = APNGUtility.ReadStream(stream, 4);

            // CRC is inverted
            calculatedCRC = ~calculatedCRC;

            // Verify the CRC
            if (ChunkCRC != calculatedCRC)
            {
                StringBuilder sb = new StringBuilder();
                sb.AppendLine(String.Format("APNG Chunk CRC Mismatch.  Chunk CRC = {0}, Calculated CRC = {1}.",
                                            ChunkCRC, calculatedCRC));
                sb.AppendLine(String.Format("This occurred while parsing the chunk at position {0} (0x{1:X8}) in the stream.",
                                            chunkStart, chunkStart));
                throw new ApplicationException(sb.ToString());
            }
        }
Exemplo n.º 5
0
        /// <summary>
        /// Attempts to read an APNG Header chunk from the supplied stream.
        /// </summary>
        /// <param name="stream">The stream containing the APNG Header</param>
        public void Read(Stream stream)
        {
            // Stream must be readable
            if (!stream.CanRead)
            {
                throw new ArgumentException("Stream is not readable");
            }

            // Read the signature
            try
            {
                signature = APNGUtility.ReadStream(stream, 8);
            }
            catch (Exception)
            {
                // Re-throw any exceptions
                throw;
            }

            // Test signature for validity
            if (signature.Length == expectedSignature.Length)
            {
                for (int i = 0; i < expectedSignature.Length; i++)
                {
                    // Invalid signature
                    if (expectedSignature[i] != signature[i])
                    {
                        throw new ApplicationException("APNG signature not found.");
                    }
                }
            }
            else
            {
                // Invalid signature
                throw new ApplicationException("APNG signature not found.");
            }
        }
Exemplo n.º 6
0
        /// <summary>
        /// Extracts various fields specific to this chunk from the APNG's
        /// data field
        /// </summary>
        /// <param name="chunkData">An array of bytes representing the APNG's data field</param>
        protected override void ParseData(byte[] chunkData)
        {
            int offset = 0;

            redBackground   = APNGUtility.ParseUint(chunkData, 2, ref offset);
            greenBackground = APNGUtility.ParseUint(chunkData, 2, ref offset);
            blueBackground  = APNGUtility.ParseUint(chunkData, 2, ref offset);

            // If the data length is > 6 then read 1 more byte
            if (chunkData.Length > 6)
            {
                mandatoryBackground = APNGUtility.ParseUint(chunkData, 1, ref offset);
            }
            // If the data length is > 7 then read 2 more bytes
            if (chunkData.Length > 7)
            {
                backgroundImageId = APNGUtility.ParseUint(chunkData, 2, ref offset);
            }
            // If the data length is > 9 then read 1 more byte
            if (chunkData.Length > 9)
            {
                backgroundTiling = APNGUtility.ParseUint(chunkData, 1, ref offset);
            }
        }