The Image Validator Procedure¶
Input data¶
One or two graphic images is the input of the program.
The program recognizes various graphic formats:
- tiff
- jpeg
- png
- jpeg2000
- djvu
- FITS
Identification¶
The program identifies a format of an image by an extension used in a file name:
- tiff: *.tiff, *.tif
- djvu: *.djvu
- jpeg 2000: *.jp2000, *.jpf, *.jp2, *.jpp
- jpeg: *.jpeg, *.jpg
- pdf: *.pdf
- png: *.png
- fits: *.fits
Note
Users can add more extensions into the file differ-cmdline/src/main/resources/appCtx-differ-cmdline.xml and into the corresponding xml file exiftoolMetadataExtractor.xml or exiv2MetadataExtractor.xml or fitsMetadataExtractor.xml or imagemagickMetadataExtractor.xml or jhoveMetadataExtractor.xml or jpylyzerMetadataExtractor.xml or kakaduMetadataExtractor.xml
The xml tag supportedFileExtensions holds information about which file name extensions the given metadata extractor recognizes.
Important
Users must call mvn package in the directory differ-cmdline everytime he or she changes xml files.
Validation and Characterization¶
The program collects the information calling various image metadata extractors.
A type of the information can be:
identification:
the information tells basic information about image file or tells basic structural information about image format.
characterization:
the information describes image in detail.
validation:
the information tells that image format is valid and well formed.
The program calls various external programs to extract image metadata depending on image format:
- TIFF
- Exiftool
- Exiv2
- Fits
- Imagemagick
- Jhove
- JPEG
- Exiftool
- Exiv2
- Fits
- Imagemagick
- Jhove
- Daitss
- DjVu
- Exiftool
- Exiv2
- Fits
- Imagemagick
- Jhove
- Daitss
- JPEG 2000
- Exiftool
- Exiv2
- Fits
- Imagemagick
- Jhove
- Daitss
- JPylyzer
- KDU_expand
TODO: png, pdf, djvu, fits doplnit plus nastroje
Note
Detailed information about each external program can be seen in `Recognized Extractor Outputs`_.