gdalinfo.js

var gdal = require('../lib/gdal.js');
var util = require('util');

var filename = process.argv[2];
if (!filename) {
	console.error('Filename must be provided');
	process.exit(1);
}

var ds = gdal.open(filename);

var driver = ds.driver;
var driver_metadata = driver.getMetadata();
if (driver_metadata['DCAP_RASTER'] !== 'YES') {
	console.error('Source file is not a raster');
	process.exit(1);
}

console.log('Driver: ' + driver.description);

// raster dimensions
var size = ds.rasterSize;
console.log('Size is ' + size.x + ', ' + size.y);

// spatial reference
console.log('Coordinate System is: ');
console.log(ds.srs.toPrettyWKT());

// geotransform
var geotransform = ds.geoTransform;
console.log('Origin = (' + geotransform[0] + ', ' + geotransform[3] + ')');
console.log('Pixel Size = (' + geotransform[1] + ', ' + geotransform[5] + ')');
console.log('GeoTransform =');
console.log(geotransform);

// corners
var corners = {
	'Upper Left  ' : {x: 0, y: 0},
	'Upper Right ' : {x: size.x, y: 0},
	'Bottom Right' : {x: size.x, y: size.y},
	'Bottom Left ' : {x: 0, y: size.y},
	'Center      ' : {x: size.x / 2, y: size.y / 2}
};

var wgs84 = gdal.SpatialReference.fromEPSG(4326);
var coord_transform = new gdal.CoordinateTransformation(ds.srs, wgs84);

console.log('Corner Coordinates:');
var corner_names = Object.keys(corners);
corner_names.forEach(function(corner_name) {
	// convert pixel x,y to the coordinate system of the raster
	// then transform it to WGS84
	var corner      = corners[corner_name];
	var pt_orig     = {
		x: geotransform[0] + corner.x * geotransform[1] + corner.y * geotransform[2],
		y: geotransform[3] + corner.x * geotransform[4] + corner.y * geotransform[5]
	};
	var pt_wgs84    = coord_transform.transformPoint(pt_orig);
	var description = util.format('%s (%d, %d) (%s, %s)',
		corner_name,
		Math.floor(pt_orig.x * 100) / 100,
		Math.floor(pt_orig.y * 100) / 100,
		gdal.decToDMS(pt_wgs84.x, 'Long'),
		gdal.decToDMS(pt_wgs84.y, 'Lat')
	);
	console.log(description);
});

// bands
ds.bands.forEach(function(band) {
	var description = util.format('Band %d Block=%dx%d Type=%s, ColorInterp=%s',
		band.id,
		band.blockSize.x,
		band.blockSize.y,
		band.dataType,
		band.colorInterpretation
	);
	console.log(description);

	if (band.description) {
		console.log('  Description = ' + band.description);
	}
	console.log('  Min=' + Math.floor(band.minimum * 1000) / 1000);
	console.log('  Max=' + Math.floor(band.maximum * 1000) / 1000);
	if (band.noDataValue !== null) {
		console.log('  NoData Value=' + band.noDataValue);
	}

	// band overviews
	var overview_info = [];
	band.overviews.forEach(function(overview) {
		var overview_description = overview.size.x + 'x' + overview.size.y;

		var metadata = overview.getMetadata();
		if (metadata['RESAMPLING'] === 'AVERAGE_BIT2') {
			overview_description += '*';
		}

		overview_info.push();
	});

	if (overview_info.length > 0) {
		console.log('  Overviews: ' + overview_info.join(', '));
	}
	if (band.hasArbitraryOverviews) {
		console.log('  Overviews: arbitrary');
	}
	if (band.unitType) {
		console.log('  Unit Type: ' + band.unitType);
	}

	// category names
	var category_names = band.categoryNames;
	if (category_names.length > 0) {
		console.log('  Category Names: ');
		for (var i = 0; i < category_names.length; i++) {
			console.log('    ' + i + ': ' + category_names[i]);
		}
	}

	if (band.scale !== 1 || band.offset !== 0) {
		console.log('  Offset: ' + band.offset + ',   Scale: ' + band.scale);
	}

	// band metadata
	var metadata = band.getMetadata();
	var keys = Object.keys(metadata);
	if (keys.length > 0) {
		console.log('  Metadata:');
		keys.forEach(function(key) {
			console.log('    ' + key + '=' + metadata[key]);
		});
	}

	metadata = band.getMetadata('IMAGE_STRUCTURE');
	keys = Object.keys(metadata);
	if (keys.length > 0) {
		console.log('  Image Structure Metadata:');
		keys.forEach(function(key) {
			console.log('    ' + key + '=' + metadata[key]);
		});
	}
});