RasterCommentMetadata Class

RasterCommentMetadataExamples.prototype.RasterCommentMetadataExample = function () {
    Tools.SetLicense();
    with (Leadtools) {
        with (Leadtools.Codecs) {
            with (Leadtools.ImageProcessing) {
                var codecs = new RasterCodecs();

                codecs.throwExceptionsOnInvalidImages = true;

                var srcFileName = "Assets\\Image1.cmp";
                var destFileName = "Image1_comments.tif";
                var image;
                var comment;
                var saveFile;
                var artistNameWrite = "Artist name";
                var rationalsWrite = new Array(3);
                // Load the image
                return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) {
                    return codecs.loadAsync(LeadStreamFactory.create(loadFile))
                })
                    .then(function (img) {
                        image = img;

                        //Save as tif
                        return Tools.AppLocalFolder().createFileAsync(destFileName)
                    })
                    .then(function (sveFile) {
                        saveFile = sveFile;
                        return codecs.saveAsync(image, LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 24)
                    })
                    .then(function () {

                        image.close();

                        // Write some comments to the existing tif file
                        comment = new RasterCommentMetadata();
                        comment.type = RasterCommentMetadataType.artist;
                        
                        comment.fromAscii(artistNameWrite);
                        console.info("Writing Artist");
                        return codecs.writeCommentAsync(LeadStreamFactory.create(saveFile), 1, comment)
                    })
                    .then(function () {

                        comment = new RasterCommentMetadata();
                        comment.type = RasterCommentMetadataType.gpsLatitude;
                        
                        for (var i = 0; i < rationalsWrite.length; i++)
                            rationalsWrite[i] = RasterMetadataRationalHelper.create(i + 3, i + 2);

                        comment.fromRational(rationalsWrite);
                        console.info("Writing GpsLatitude");
                        return codecs.writeCommentAsync(LeadStreamFactory.create(saveFile), 1, comment)
                    })
                    .then(function () {

                        // Now read the comments from the tif file

                        // read ASCII
                        return codecs.readCommentAsync(LeadStreamFactory.create(saveFile), 1, RasterCommentMetadataType.artist)
                    })
                    .then(function (cmnt) {
                        comment = cmnt;

                        var artistNameRead = comment.toAscii();
                        console.info("Artist: ", artistNameRead);
                        console.assert(artistNameRead == artistNameWrite, "artistNameRead == artistNameWrite");

                        // read rationals
                        return codecs.readCommentAsync(LeadStreamFactory.create(saveFile), 1, RasterCommentMetadataType.gpsLatitude)})
                    .then(function (cmnt1) {
                        comment = cmnt1;
                        var rationalsRead = comment.toRational();

                        var size = rationalsRead.length;
                        console.info("GpsLatitude: size = ", size);
                        for (var i = 0; i < size; i++)
                            console.info(rationalsRead[i].numerator + "/" + rationalsRead[i].denominator);

                        console.assert(rationalsRead.length == rationalsWrite.length);

                        for (var i = 0; i < rationalsRead.length; i++) {
                            console.assert(rationalsRead[i].numerator === rationalsWrite[i].numerator,"rationalsRead[i].numerator === rationalsWrite[i].numerator");
                            console.assert(rationalsRead[i].denominator == rationalsWrite[i].denominator, "rationalsRead[i].denominator == rationalsWrite[i].denominator");
                        }
                    });
            }
        }
    }
}