public virtual void TestGetUInt8()
{
sbyte[] buffer = new sbyte[] { unchecked ((int)(0x00)), unchecked ((int)(0x01)), unchecked ((sbyte)unchecked ((int)(0x7F))), unchecked ((sbyte)unchecked ((int)(0xFF))) };
SequentialReader reader = CreateReader(buffer);
Sharpen.Tests.AreEqual(0, reader.GetUInt8());
Sharpen.Tests.AreEqual(1, reader.GetUInt8());
Sharpen.Tests.AreEqual(127, reader.GetUInt8());
Sharpen.Tests.AreEqual(255, reader.GetUInt8());
}
public virtual void TestGetUInt8_OutOfBounds()
{
try
{
SequentialReader reader = CreateReader(new sbyte[1]);
reader.GetUInt8();
reader.GetUInt8();
NUnit.Framework.Assert.Fail("Exception expected");
}
catch (IOException ex)
{
Sharpen.Tests.AreEqual("End of data reached.", ex.Message);
}
}
public virtual void Extract(SequentialReader reader, Com.Drew.Metadata.Metadata metadata)
{
GifHeaderDirectory directory = metadata.GetOrCreateDirectory<GifHeaderDirectory>();
// FILE HEADER
//
// 3 - signature: "GIF"
// 3 - version: either "87a" or "89a"
//
// LOGICAL SCREEN DESCRIPTOR
//
// 2 - pixel width
// 2 - pixel height
// 1 - screen and color map information flags (0 is LSB)
// 0-2 Size of the global color table
// 3 Color table sort flag (89a only)
// 4-6 Color resolution
// 7 Global color table flag
// 1 - background color index
// 1 - pixel aspect ratio
reader.SetMotorolaByteOrder(false);
try
{
string signature = reader.GetString(3);
if (!signature.Equals("GIF"))
{
directory.AddError("Invalid GIF file signature");
return;
}
string version = reader.GetString(3);
if (!version.Equals(Gif87aVersionIdentifier) && !version.Equals(Gif89aVersionIdentifier))
{
directory.AddError("Unexpected GIF version");
return;
}
directory.SetString(GifHeaderDirectory.TagGifFormatVersion, version);
directory.SetInt(GifHeaderDirectory.TagImageWidth, reader.GetUInt16());
directory.SetInt(GifHeaderDirectory.TagImageHeight, reader.GetUInt16());
short flags = reader.GetUInt8();
// First three bits = (BPP - 1)
int colorTableSize = 1 << ((flags & 7) + 1);
directory.SetInt(GifHeaderDirectory.TagColorTableSize, colorTableSize);
if (version.Equals(Gif89aVersionIdentifier))
{
bool isColorTableSorted = (flags & 8) != 0;
directory.SetBoolean(GifHeaderDirectory.TagIsColorTableSorted, isColorTableSorted);
}
int bitsPerPixel = ((flags & unchecked((int)(0x70))) >> 4) + 1;
directory.SetInt(GifHeaderDirectory.TagBitsPerPixel, bitsPerPixel);
bool hasGlobalColorTable = (flags & unchecked((int)(0xf))) != 0;
directory.SetBoolean(GifHeaderDirectory.TagHasGlobalColorTable, hasGlobalColorTable);
directory.SetInt(GifHeaderDirectory.TagTransparentColorIndex, reader.GetUInt8());
int aspectRatioByte = reader.GetUInt8();
if (aspectRatioByte != 0)
{
float pixelAspectRatio = (float)((aspectRatioByte + 15d) / 64d);
directory.SetFloat(GifHeaderDirectory.TagPixelAspectRatio, pixelAspectRatio);
}
}
catch (IOException)
{
directory.AddError("Unable to read BMP header");
}
}
/// <summary>
/// Performs the IPTC data extraction, adding found values to the specified instance of
/// <see cref="Com.Drew.Metadata.Metadata"/>
/// .
/// </summary>
public virtual void Extract(SequentialReader reader, Com.Drew.Metadata.Metadata metadata, long length)
{
IptcDirectory directory = metadata.GetOrCreateDirectory<IptcDirectory>();
int offset = 0;
// for each tag
while (offset < length)
{
// identifies start of a tag
short startByte;
try
{
startByte = reader.GetUInt8();
offset++;
}
catch (IOException)
{
directory.AddError("Unable to read starting byte of IPTC tag");
return;
}
if (startByte != unchecked((int)(0x1c)))
{
directory.AddError("Invalid start to IPTC tag");
return;
}
// we need at least five bytes left to read a tag
if (offset + 5 >= length)
{
directory.AddError("Too few bytes remain for a valid IPTC tag");
return;
}
int directoryType;
int tagType;
int tagByteCount;
try
{
directoryType = reader.GetUInt8();
tagType = reader.GetUInt8();
tagByteCount = reader.GetUInt16();
offset += 4;
}
catch (IOException)
{
directory.AddError("IPTC data segment ended mid-way through tag descriptor");
return;
}
if (offset + tagByteCount > length)
{
directory.AddError("Data for tag extends beyond end of IPTC segment");
return;
}
try
{
ProcessTag(reader, directory, directoryType, tagType, tagByteCount);
}
catch (IOException)
{
directory.AddError("Error processing IPTC tag");
return;
}
offset += tagByteCount;
}
}
/// <exception cref="System.IO.IOException"/>
private void ProcessTag(SequentialReader reader, Com.Drew.Metadata.Directory directory, int directoryType, int tagType, int tagByteCount)
{
int tagIdentifier = tagType | (directoryType << 8);
string @string = null;
switch (tagIdentifier)
{
case IptcDirectory.TagApplicationRecordVersion:
{
// short
int shortValue = reader.GetUInt16();
reader.Skip(tagByteCount - 2);
directory.SetInt(tagIdentifier, shortValue);
return;
}
case IptcDirectory.TagUrgency:
{
// byte
directory.SetInt(tagIdentifier, reader.GetUInt8());
reader.Skip(tagByteCount - 1);
return;
}
case IptcDirectory.TagReleaseDate:
case IptcDirectory.TagDateCreated:
{
// Date object
if (tagByteCount >= 8)
{
@string = reader.GetString(tagByteCount);
try
{
int year = System.Convert.ToInt32(Sharpen.Runtime.Substring(@string, 0, 4));
int month = System.Convert.ToInt32(Sharpen.Runtime.Substring(@string, 4, 6)) - 1;
int day = System.Convert.ToInt32(Sharpen.Runtime.Substring(@string, 6, 8));
DateTime date = new Sharpen.GregorianCalendar(year, month, day).GetTime();
directory.SetDate(tagIdentifier, date);
return;
}
catch (FormatException)
{
}
}
else
{
// fall through and we'll process the 'string' value below
reader.Skip(tagByteCount);
}
goto case IptcDirectory.TagReleaseTime;
}
case IptcDirectory.TagReleaseTime:
case IptcDirectory.TagTimeCreated:
default:
{
break;
}
}
// time...
// fall through
// If we haven't returned yet, treat it as a string
// NOTE that there's a chance we've already loaded the value as a string above, but failed to parse the value
if (@string == null)
{
@string = reader.GetString(tagByteCount, Runtime.GetProperty("file.encoding"));
}
// "ISO-8859-1"
if (directory.ContainsTag(tagIdentifier))
{
// this fancy string[] business avoids using an ArrayList for performance reasons
string[] oldStrings = directory.GetStringArray(tagIdentifier);
string[] newStrings;
if (oldStrings == null)
{
newStrings = new string[1];
}
else
{
newStrings = new string[oldStrings.Length + 1];
System.Array.Copy(oldStrings, 0, newStrings, 0, oldStrings.Length);
}
newStrings[newStrings.Length - 1] = @string;
directory.SetStringArray(tagIdentifier, newStrings);
}
else
{
directory.SetString(tagIdentifier, @string);
}
}
public static JpegSegmentData ReadSegments(SequentialReader reader, Iterable<JpegSegmentType> segmentTypes)
{
// Must be big-endian
System.Diagnostics.Debug.Assert((reader.IsMotorolaByteOrder()));
// first two bytes should be JPEG magic number
int magicNumber = reader.GetUInt16();
if (magicNumber != unchecked((int)(0xFFD8)))
{
throw new JpegProcessingException("JPEG data is expected to begin with 0xFFD8 (ГїГ�) not 0x" + Sharpen.Extensions.ToHexString(magicNumber));
}
ICollection<sbyte> segmentTypeBytes = null;
if (segmentTypes != null)
{
segmentTypeBytes = new HashSet<sbyte>();
foreach (JpegSegmentType segmentType in segmentTypes)
{
segmentTypeBytes.Add(segmentType.byteValue);
}
}
JpegSegmentData segmentData = new JpegSegmentData();
do
{
// next byte is the segment identifier: 0xFF
short segmentIdentifier = reader.GetUInt8();
if (segmentIdentifier != unchecked((int)(0xFF)))
{
throw new JpegProcessingException("Expected JPEG segment start identifier 0xFF, not 0x" + Sharpen.Extensions.ToHexString(segmentIdentifier));
}
// next byte is the segment type
sbyte segmentType = reader.GetInt8();
if (segmentType == SegmentSos)
{
// The 'Start-Of-Scan' segment's length doesn't include the image data, instead would
// have to search for the two bytes: 0xFF 0xD9 (EOI).
// It comes last so simply return at this point
return segmentData;
}
if (segmentType == MarkerEoi)
{
// the 'End-Of-Image' segment -- this should never be found in this fashion
return segmentData;
}
// next 2-bytes are <segment-size>: [high-byte] [low-byte]
int segmentLength = reader.GetUInt16();
// segment length includes size bytes, so subtract two
segmentLength -= 2;
if (segmentLength < 0)
{
throw new JpegProcessingException("JPEG segment size would be less than zero");
}
// Check whether we are interested in this segment
if (segmentTypeBytes == null || segmentTypeBytes.Contains(segmentType))
{
sbyte[] segmentBytes = reader.GetBytes(segmentLength);
System.Diagnostics.Debug.Assert((segmentLength == segmentBytes.Length));
segmentData.AddSegment(segmentType, segmentBytes);
}
else
{
// Some if the JPEG is truncated, just return what data we've already gathered
if (!reader.TrySkip(segmentLength))
{
return segmentData;
}
}
}
while (true);
}