lsm/PdfPig
1
0
Fork 0
mirror of https://github.com/UglyToad/PdfPig.git synced 2025-04-05 20:55:01 +08:00
Code Issues Actions 1 Packages Projects Releases Wiki Activity

Add indexed color space for stencils

Browse Source
This commit is contained in:
Kasper Frank 2021-05-07 11:51:41 +02:00
parent 8c6f705d2a
commit f8990a79b8
3 changed files with 22 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/UglyToad.PdfPig.Tests/Images/PngFromPdfImageFactoryTests.cs
View File

@ -150,7 +150,7 @@
var decodedBytes = ImageHelpers.LoadFileBytes("ccittfax-decoded.bin");
var image = new TestPdfImage
{
ColorSpaceDetails = IndexedColorSpaceDetails.CCITTFaxColorSpaceDetails,
ColorSpaceDetails = IndexedColorSpaceDetails.StencilBlackIs1,
DecodedBytes = decodedBytes,
WidthInSamples = 1800,
HeightInSamples = 3113,

20
src/UglyToad.PdfPig/Graphics/Colors/ColorSpaceDetails.cs
View File

@ -85,13 +85,25 @@
public class IndexedColorSpaceDetails : ColorSpaceDetails
{
/// <summary>
/// The lossless CCITT compression schemes are used for bitonal black and white images.
/// This is equivalent to an IndexedColorSpaceDetails with a black and white palette.
/// A color space useful for extracting stencil masks as black-and-white images.
/// Index 0 is black and index 1 is white.
/// </summary>
internal static readonly IndexedColorSpaceDetails StencilBlackIs0
= new IndexedColorSpaceDetails(DeviceGrayColorSpaceDetails.Instance, 1, new byte[] { 0, 255 });
/// <summary>
/// A color space useful for extracting stencil masks as black-and-white images.
/// Index 0 is white and index 1 is black.
/// </summary>
internal static readonly IndexedColorSpaceDetails CCITTFaxColorSpaceDetails
internal static readonly IndexedColorSpaceDetails StencilBlackIs1
= new IndexedColorSpaceDetails(DeviceGrayColorSpaceDetails.Instance, 1, new byte[] { 255, 0 });
internal static ColorSpaceDetails Stencil(decimal[] decode)
{
return decode.Length >= 2 && decode[0] == 1 && decode[1] == 0 ?
StencilBlackIs1 : StencilBlackIs0 /* default */;
}
/// <summary>
/// The base color space in which the values in the color table are to be interpreted.
/// It can be any device or CIE-based color space or(in PDF 1.3) a Separation or DeviceN space,
@ -119,7 +131,7 @@
HiVal = hiVal;
ColorTable = colorTable;
BaseType = baseColorSpaceDetails.BaseType;
}
}
}
/// <summary>

7
src/UglyToad.PdfPig/Util/ColorSpaceDetailsParser.cs
View File

@ -75,9 +75,12 @@
ILookupFilterProvider filterProvider,
bool cannotRecurse = false)
{
if (filterProvider.GetFilters(imageDictionary).OfType<CcittFaxDecodeFilter>().Any())
if (imageDictionary.GetDictionaryObject(NameToken.ImageMask, NameToken.Im) != null)
{
return IndexedColorSpaceDetails.CCITTFaxColorSpaceDetails;
var decodeRaw = imageDictionary.GetDictionaryObject(NameToken.Decode, NameToken.D) as ArrayToken
?? new ArrayToken(EmptyArray<IToken>.Instance);
var decode = decodeRaw.Data.OfType<NumericToken>().Select(x => x.Data).ToArray();
return IndexedColorSpaceDetails.Stencil(decode);
}
if (!colorSpace.HasValue)