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Diffstat (limited to 'Emby.Drawing/Common/ImageHeader.cs')
| -rw-r--r-- | Emby.Drawing/Common/ImageHeader.cs | 223 |
1 files changed, 0 insertions, 223 deletions
diff --git a/Emby.Drawing/Common/ImageHeader.cs b/Emby.Drawing/Common/ImageHeader.cs deleted file mode 100644 index 1c70b3bb6..000000000 --- a/Emby.Drawing/Common/ImageHeader.cs +++ /dev/null @@ -1,223 +0,0 @@ -using MediaBrowser.Common.IO; -using MediaBrowser.Model.Drawing; -using MediaBrowser.Model.Logging; -using System; -using System.Collections.Generic; -using System.IO; -using System.Linq; - -namespace Emby.Drawing.Common -{ - /// <summary> - /// Taken from http://stackoverflow.com/questions/111345/getting-image-dimensions-without-reading-the-entire-file/111349 - /// http://www.codeproject.com/Articles/35978/Reading-Image-Headers-to-Get-Width-and-Height - /// Minor improvements including supporting unsigned 16-bit integers when decoding Jfif and added logic - /// to load the image using new Bitmap if reading the headers fails - /// </summary> - public static class ImageHeader - { - /// <summary> - /// The error message - /// </summary> - const string ErrorMessage = "Could not recognize image format."; - - /// <summary> - /// The image format decoders - /// </summary> - private static readonly KeyValuePair<byte[], Func<BinaryReader, ImageSize>>[] ImageFormatDecoders = new Dictionary<byte[], Func<BinaryReader, ImageSize>> - { - { new byte[] { 0x42, 0x4D }, DecodeBitmap }, - { new byte[] { 0x47, 0x49, 0x46, 0x38, 0x37, 0x61 }, DecodeGif }, - { new byte[] { 0x47, 0x49, 0x46, 0x38, 0x39, 0x61 }, DecodeGif }, - { new byte[] { 0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A }, DecodePng }, - { new byte[] { 0xff, 0xd8 }, DecodeJfif } - - }.ToArray(); - - private static readonly int MaxMagicBytesLength = ImageFormatDecoders.Select(i => i.Key.Length).OrderByDescending(i => i).First(); - - /// <summary> - /// Gets the dimensions of an image. - /// </summary> - /// <param name="path">The path of the image to get the dimensions of.</param> - /// <param name="logger">The logger.</param> - /// <param name="fileSystem">The file system.</param> - /// <returns>The dimensions of the specified image.</returns> - /// <exception cref="ArgumentException">The image was of an unrecognised format.</exception> - public static ImageSize GetDimensions(string path, ILogger logger, IFileSystem fileSystem) - { - using (var fs = fileSystem.OpenRead(path)) - { - using (var binaryReader = new BinaryReader(fs)) - { - return GetDimensions(binaryReader); - } - } - } - - /// <summary> - /// Gets the dimensions of an image. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>Size.</returns> - /// <exception cref="System.ArgumentException">binaryReader</exception> - /// <exception cref="ArgumentException">The image was of an unrecognized format.</exception> - private static ImageSize GetDimensions(BinaryReader binaryReader) - { - var magicBytes = new byte[MaxMagicBytesLength]; - - for (var i = 0; i < MaxMagicBytesLength; i += 1) - { - magicBytes[i] = binaryReader.ReadByte(); - - foreach (var kvPair in ImageFormatDecoders) - { - if (StartsWith(magicBytes, kvPair.Key)) - { - return kvPair.Value(binaryReader); - } - } - } - - throw new ArgumentException(ErrorMessage, "binaryReader"); - } - - /// <summary> - /// Startses the with. - /// </summary> - /// <param name="thisBytes">The this bytes.</param> - /// <param name="thatBytes">The that bytes.</param> - /// <returns><c>true</c> if XXXX, <c>false</c> otherwise</returns> - private static bool StartsWith(byte[] thisBytes, byte[] thatBytes) - { - for (int i = 0; i < thatBytes.Length; i += 1) - { - if (thisBytes[i] != thatBytes[i]) - { - return false; - } - } - - return true; - } - - /// <summary> - /// Reads the little endian int16. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>System.Int16.</returns> - private static short ReadLittleEndianInt16(BinaryReader binaryReader) - { - var bytes = new byte[sizeof(short)]; - - for (int i = 0; i < sizeof(short); i += 1) - { - bytes[sizeof(short) - 1 - i] = binaryReader.ReadByte(); - } - return BitConverter.ToInt16(bytes, 0); - } - - /// <summary> - /// Reads the little endian int32. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>System.Int32.</returns> - private static int ReadLittleEndianInt32(BinaryReader binaryReader) - { - var bytes = new byte[sizeof(int)]; - for (int i = 0; i < sizeof(int); i += 1) - { - bytes[sizeof(int) - 1 - i] = binaryReader.ReadByte(); - } - return BitConverter.ToInt32(bytes, 0); - } - - /// <summary> - /// Decodes the bitmap. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>Size.</returns> - private static ImageSize DecodeBitmap(BinaryReader binaryReader) - { - binaryReader.ReadBytes(16); - int width = binaryReader.ReadInt32(); - int height = binaryReader.ReadInt32(); - return new ImageSize - { - Width = width, - Height = height - }; - } - - /// <summary> - /// Decodes the GIF. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>Size.</returns> - private static ImageSize DecodeGif(BinaryReader binaryReader) - { - int width = binaryReader.ReadInt16(); - int height = binaryReader.ReadInt16(); - return new ImageSize - { - Width = width, - Height = height - }; - } - - /// <summary> - /// Decodes the PNG. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>Size.</returns> - private static ImageSize DecodePng(BinaryReader binaryReader) - { - binaryReader.ReadBytes(8); - int width = ReadLittleEndianInt32(binaryReader); - int height = ReadLittleEndianInt32(binaryReader); - return new ImageSize - { - Width = width, - Height = height - }; - } - - /// <summary> - /// Decodes the jfif. - /// </summary> - /// <param name="binaryReader">The binary reader.</param> - /// <returns>Size.</returns> - /// <exception cref="System.ArgumentException"></exception> - private static ImageSize DecodeJfif(BinaryReader binaryReader) - { - while (binaryReader.ReadByte() == 0xff) - { - byte marker = binaryReader.ReadByte(); - short chunkLength = ReadLittleEndianInt16(binaryReader); - if (marker == 0xc0) - { - binaryReader.ReadByte(); - int height = ReadLittleEndianInt16(binaryReader); - int width = ReadLittleEndianInt16(binaryReader); - return new ImageSize - { - Width = width, - Height = height - }; - } - - if (chunkLength < 0) - { - var uchunkLength = (ushort)chunkLength; - binaryReader.ReadBytes(uchunkLength - 2); - } - else - { - binaryReader.ReadBytes(chunkLength - 2); - } - } - - throw new ArgumentException(ErrorMessage); - } - } -} |