tsai
/
ImageSharp
mirror of https://github.com/SixLabors/ImageSharp
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

try improve reading ext 

values
pull/1760/head
Ildar Khayrutdinov 4 years ago
parent
789dc78864
commit
ebb277a794
3 changed files with 41 additions and 51 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 25
      src/ImageSharp/Formats/Tiff/Ifd/DirectoryReader.cs
  2. 10
      src/ImageSharp/Formats/Tiff/Ifd/EntryReader.cs
  3. 57
      src/ImageSharp/Metadata/Profiles/Exif/ExifReader.cs

25
src/ImageSharp/Formats/Tiff/Ifd/DirectoryReader.cs
View File

@ -18,10 +18,6 @@ namespace SixLabors.ImageSharp.Formats.Tiff
private ulong nextIfdOffset;
// used for sequential read big values (actual for multiframe big files)
// todo: different tags can link to the same data (stream offset) - investigate
private readonly SortedList<ulong, Action> lazyLoaders = new SortedList<ulong, Action>(new DuplicateKeyComparer<ulong>());
public DirectoryReader(Stream stream) => this.stream = stream;
/// <summary>
@ -68,23 +64,28 @@ namespace SixLabors.ImageSharp.Formats.Tiff
var readers = new List<EntryReader>();
while (this.nextIfdOffset != 0 && this.nextIfdOffset < (ulong)this.stream.Length)
{
var reader = new EntryReader(this.stream, this.ByteOrder, this.lazyLoaders);
var reader = new EntryReader(this.stream, this.ByteOrder);
reader.ReadTags(isBigTiff, this.nextIfdOffset);
this.nextIfdOffset = reader.NextIfdOffset;
if (reader.ExtTags.Count > 0)
{
reader.ExtTags.Sort((t1, t2) => t1.offset.CompareTo(t2.offset));
readers.Add(reader);
}
if (reader.ExtTags[0].offset < reader.NextIfdOffset)
{
// this means that most likely all elements are placed before next IFD
reader.ReadExtValues();
}
}
// Sequential reading big values.
foreach (Action loader in this.lazyLoaders.Values)
{
loader();
this.nextIfdOffset = reader.NextIfdOffset;
readers.Add(reader);
}
var list = new List<ExifProfile>(readers.Count);
foreach (EntryReader reader in readers)
{
reader.ReadExtValues();
var profile = new ExifProfile(reader.Values, reader.InvalidTags);
list.Add(profile);
}

10
src/ImageSharp/Formats/Tiff/Ifd/EntryReader.cs
View File

@ -12,13 +12,10 @@ namespace SixLabors.ImageSharp.Formats.Tiff
{
internal class EntryReader : BaseExifReader
{
private readonly SortedList<ulong, Action> lazyLoaders;
public EntryReader(Stream stream, ByteOrder byteOrder, SortedList<ulong, Action> lazyLoaders)
public EntryReader(Stream stream, ByteOrder byteOrder)
: base(stream)
{
this.IsBigEndian = byteOrder == ByteOrder.BigEndian;
this.lazyLoaders = lazyLoaders;
}
public List<IExifValue> Values { get; } = new List<IExifValue>();
@ -43,8 +40,7 @@ namespace SixLabors.ImageSharp.Formats.Tiff
}
}
protected override void RegisterExtLoader(ulong offset, Action reader) =>
this.lazyLoaders.Add(offset, reader);
public void ReadExtValues() => this.ReadExtValues(this.Values);
}
internal class HeaderReader : BaseExifReader
@ -81,7 +77,5 @@ namespace SixLabors.ImageSharp.Formats.Tiff
TiffThrowHelper.ThrowInvalidHeader();
}
protected override void RegisterExtLoader(ulong offset, Action reader) => throw new NotSupportedException();
}
}

57
src/ImageSharp/Metadata/Profiles/Exif/ExifReader.cs
View File

@ -14,8 +14,6 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
{
internal class ExifReader : BaseExifReader
{
private readonly List<Action> loaders = new List<Action>();
public ExifReader(byte[] exifData)
: base(new MemoryStream(exifData ?? throw new ArgumentNullException(nameof(exifData))))
{
@ -41,22 +39,16 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
uint ifdOffset = this.ReadUInt32();
this.ReadValues(values, ifdOffset);
this.ReadExtValues(values);
uint thumbnailOffset = this.ReadUInt32();
this.GetThumbnail(thumbnailOffset);
this.ReadSubIfd(values);
foreach (Action loader in this.loaders)
{
loader();
}
return values;
}
protected override void RegisterExtLoader(ulong offset, Action loader) => this.loaders.Add(loader);
private void GetThumbnail(uint offset)
{
if (offset == 0)
@ -121,7 +113,17 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
public bool IsBigEndian { get; protected set; }
protected abstract void RegisterExtLoader(ulong offset, Action loader);
public List<(ulong offset, ExifDataType dataType, ulong numberOfComponents, ExifValue exif)> ExtTags { get; } = new ();
protected void ReadExtValues(List<IExifValue> values)
{
foreach ((ulong offset, ExifDataType dataType, ulong numberOfComponents, ExifValue exif) tag in this.ExtTags)
{
this.ReadExtValue(values, tag);
}
this.ExtTags.Clear();
}
/// <summary>
/// Reads the values to the values collection.
@ -173,6 +175,18 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
}
}
protected void ReadExtValue(IList<IExifValue> values, (ulong offset, ExifDataType dataType, ulong numberOfComponents, ExifValue exif) tag)
{
ulong size = tag.numberOfComponents * ExifDataTypes.GetSize(tag.dataType);
byte[] dataBuffer = new byte[size];
this.Seek(tag.offset);
if (this.TryReadSpan(dataBuffer))
{
object value = this.ConvertValue(tag.dataType, dataBuffer, tag.numberOfComponents);
this.Add(values, tag.exif, value);
}
}
protected void ReadSubIfd64(List<IExifValue> values)
{
if (this.exifOffset != 0)
@ -375,21 +389,11 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
return;
}
this.RegisterExtLoader(newOffset, () =>
{
byte[] dataBuffer = new byte[size];
this.Seek(newOffset);
if (this.TryReadSpan(dataBuffer))
{
object value = this.ConvertValue(dataType, dataBuffer, numberOfComponents);
this.Add(values, exifValue, value);
}
});
this.ExtTags.Add((newOffset, dataType, numberOfComponents, exifValue));
}
else
{
object value = this.ConvertValue(dataType, this.offsetBuffer, numberOfComponents);
this.Add(values, exifValue, value);
}
}
@ -465,16 +469,7 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
return;
}
this.RegisterExtLoader(newOffset, () =>
{
byte[] dataBuffer = new byte[size];
this.Seek(newOffset);
if (this.TryReadSpan(dataBuffer))
{
object value = this.ConvertValue(dataType, dataBuffer, numberOfComponents);
this.Add(values, exifValue, value);
}
});
this.ExtTags.Add((newOffset, dataType, numberOfComponents, exifValue));
}
else
{

Write Preview
Loading…
Cancel
Save