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Fill TIFF Readme tables with current status.

pull/1570/head
Andrew Wilkinson 9 years ago
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1 changed files with 35 additions and 24 deletions
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  1. 59
      src/ImageSharp/Formats/Tiff/README.md

59
src/ImageSharp/Formats/Tiff/README.md
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@ -23,30 +23,41 @@
## Implementation Status
### Deviations from the TIFF spec (to be fixed)
- Decoder
- A Baseline TIFF reader must skip over extra components (e.g. RGB with 4 samples per pixels)
- NB: Need to handle this for both planar and chunky data
- If the SampleFormat field is present and not 1 - fail gracefully if you cannot handle this
- Compression=None should treat 16/32-BitsPerSample for all samples as SHORT/LONG (for byte order and padding rows)
- RowsPerStrip should default to 2^32-1 (effectively infinity) to store the image as a single strip
- Check Planar format data - is this encoded as strips in order RGBRGBRGB or RRRGGGBBB?
- Make sure we ignore any strips that are not needed for the image (if too many are present)
### Compression Formats
| |Encoder|Decoder|Comments |
|---------------------------|:-----:|:-----:|--------------------------|
|None | | | |
|None | | Y | |
|Ccitt1D | | | |
|PackBits | | | |
|PackBits | | Y | |
|CcittGroup3Fax | | | |
|CcittGroup4Fax | | | |
|Lzw | | | |
|Lzw | | Y | Based on ImageSharp GIF LZW implementation - this code could be modified to be (i) shared, or (ii) optimised for each case |
|Old Jpeg | | | |
|Jpeg (Technote 2) | | | |
|Deflate (Technote 2) | | | |
|Old Deflate (Technote 2) | | | |
|Deflate (Technote 2) | | Y | |
|Old Deflate (Technote 2) | | Y | |
### Photometric Interpretation Formats
| |Encoder|Decoder|Comments |
|---------------------------|:-----:|:-----:|--------------------------|
|WhiteIsZero | | | |
|BlackIsZero | | | |
|Rgb (Chunky) | | | |
|Rgb (Planar) | | | |
|PaletteColor | | | |
|WhiteIsZero | | Y | General + 1/4/8-bit optimised implementations |
|BlackIsZero | | Y | General + 1/4/8-bit optimised implementations |
|Rgb (Chunky) | | Y | General + Rgb888 optimised implementation |
|Rgb (Planar) | | Y | General implementation only |
|PaletteColor | | Y | General implementation only |
|TransparencyMask | | | |
|Separated (TIFF Extension) | | | |
|YCbCr (TIFF Extension) | | | |
@ -59,11 +70,11 @@
|---------------------------|:-----:|:-----:|--------------------------|
|NewSubfileType | | | |
|SubfileType | | | |
|ImageWidth | | | |
|ImageLength | | | |
|BitsPerSample | | | |
|Compression | | | |
|PhotometricInterpretation | | | |
|ImageWidth | | Y | |
|ImageLength | | Y | |
|BitsPerSample | | Y | |
|Compression | | Y | |
|PhotometricInterpretation | | Y | |
|Threshholding | | | |
|CellWidth | | | |
|CellLength | | | |
@ -71,26 +82,26 @@
|ImageDescription | | | |
|Make | | | |
|Model | | | |
|StripOffsets | | | |
|StripOffsets | | Y | |
|Orientation | | | |
|SamplesPerPixel | | | |
|RowsPerStrip | | | |
|StripByteCounts | | | |
|SamplesPerPixel | | | Currently ignored, as can be inferred from count of BitsPerSample |
|RowsPerStrip | | Y | |
|StripByteCounts | | Y | |
|MinSampleValue | | | |
|MaxSampleValue | | | |
|XResolution | | | |
|YResolution | | | |
|PlanarConfiguration | | | |
|XResolution | | Y | |
|YResolution | | Y | |
|PlanarConfiguration | | Y | |
|FreeOffsets | | | |
|FreeByteCounts | | | |
|GrayResponseUnit | | | |
|GrayResponseCurve | | | |
|ResolutionUnit | | | |
|ResolutionUnit | | Y | |
|Software | | | |
|DateTime | | | |
|Artist | | | |
|HostComputer | | | |
|ColorMap | | | |
|ColorMap | | Y | |
|ExtraSamples | | | |
|Copyright | | | |

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