edu.harvard.hul.ois.jhove.module.tiff.TiffProfileExif Maven / Gradle / Ivy

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/**********************************************************************
 * Jhove - JSTOR/Harvard Object Validation Environment
 * Copyright 2003 by JSTOR and the President and Fellows of Harvard College
 **********************************************************************/

package edu.harvard.hul.ois.jhove.module.tiff;

import edu.harvard.hul.ois.jhove.*;


/**
 *  Profile checker for Exif.  This applies to the main IFD
 *  of the file.  To satisfy the Exif profile, the thumbnail
 *  IFD must also satisfy TiffProfileExifThumb.
 * 
 *  @see TiffProfileExifThumb
 *  @see TiffProfileExifIFD
 */
public final class TiffProfileExif extends TiffProfile
{
    /* The profile text depends on the version. */
    private String[] profileText = { "Exif 2.0",
            "Exif 2.1 (JEIDA-49-1998)",
            "Exif 2.2 (JEITA CP-3451)"
            };
    private TiffProfileExifIFD _exifIFDProfile;
    
    public TiffProfileExif ()
    {
	super ();
	//_profileText = "Exif 2.2 (JEITA CP-3451)";
        _exifIFDProfile = new TiffProfileExifIFD ();
    }

    /**
     *  Returns true if the IFD satisfies the requirements of an
     *  Exif profile.  See the Exif specification for details.
     */
    public boolean satisfiesThisProfile (IFD ifd) 
    {
	if (!(ifd instanceof TiffIFD)) {
	    return false;
	}
	TiffIFD tifd = (TiffIFD) ifd;

	/* Check required tags. */
	NisoImageMetadata niso = tifd.getNisoImageMetadata ();
        if (niso.getXSamplingFrequency () == null ||
                niso.getYSamplingFrequency () == null) {
            return false;
        }

        if (satisfiesCompression (tifd, 1)) {
            if (niso.getImageWidth () == NisoImageMetadata.NULL ||
                    niso.getImageLength () == NisoImageMetadata.NULL ||
                    niso.getStripOffsets () == null ||
                    niso.getRowsPerStrip () == NisoImageMetadata.NULL ||
                    niso.getStripByteCounts () == null)  {
    	        return false;
            }
            if (niso.getSamplesPerPixel () != 3) {
                return false;
            }
            /* BitsPerSample must be [8, 8, 8] */
            int[] bps = niso.getBitsPerSample ();
            if (bps == null || bps.length < 3 || bps[0] != 8 || bps[1] != 8 ||
                bps[2] != 8) {
                return false;
            }
            int pInterpretation = niso.getColorSpace ();
            if (!(pInterpretation == 2 || pInterpretation == 6)) {
                return false;
            }
            if (pInterpretation == 6) {
                if (niso.getYCbCrSubSampling () == null ||
                niso.getYCbCrPositioning () == NisoImageMetadata.NULL) {
                    return false;
                }
            }
    	}
        else {
            // If the compression isn't 1, then the JPEGInterchangeFormat
            // tag must be present, but other requirements are lifted.
            if (tifd.getJpegInterchangeFormat() == NisoImageMetadata.NULL) {
                return false;
            }
        }




	if (!satisfiesResolutionUnit (tifd, new int [] {2, 3} )) {
	    return false;
	}

        /* for the first IFD only, there must be an Exif subifd */
	if (tifd.isFirst ()) {
            ExifIFD eifd = tifd.getTheExifIFD ();
            if (eifd == null) {
                return false;
            }
            // The Exif IFD must satisfy the profile requirements
            if (!_exifIFDProfile.satisfiesThisProfile(eifd)) {
                return false;
            }
            String version = eifd.getExifVersion ();
            int idx = 0;
            // If we passed the profile, the version will be one of
            // the following.
            if (version.equals ("0220")) {
                idx = 2;
            }
            else if (version.equals ("0210")) {
                idx = 1;
            }
            else if (version.equals ("0200")) {
                idx = 0;
            }
            _profileText = profileText[idx];
        }
        

	return true;
    }
}