/** @module geotiffimage */
import { getFloat16 } from '@petamoriken/float16';
import getAttribute from 'xml-utils/get-attribute.js';
import findTagsByName from 'xml-utils/find-tags-by-name.js';
import { photometricInterpretations, ExtraSamplesValues } from './globals.js';
import { fromWhiteIsZero, fromBlackIsZero, fromPalette, fromCMYK, fromYCbCr, fromCIELab } from './rgb.js';
import { getDecoder } from './compression/index.js';
import { resample, resampleInterleaved } from './resample.js';
/**
* @typedef {Object} ReadRasterOptions
* @property {Array<number>} [window=whole window] the subset to read data from in pixels.
* @property {Array<number>} [bbox=whole image] the subset to read data from in
* geographical coordinates.
* @property {Array<number>} [samples=all samples] the selection of samples to read from. Default is all samples.
* @property {boolean} [interleave=false] whether the data shall be read
* in one single array or separate
* arrays.
* @property {Pool} [pool=null] The optional decoder pool to use.
* @property {number} [width] The desired width of the output. When the width is not the
* same as the images, resampling will be performed.
* @property {number} [height] The desired height of the output. When the width is not the
* same as the images, resampling will be performed.
* @property {string} [resampleMethod='nearest'] The desired resampling method.
* @property {AbortSignal} [signal] An AbortSignal that may be signalled if the request is
* to be aborted
* @property {number|number[]} [fillValue] The value to use for parts of the image
* outside of the images extent. When multiple
* samples are requested, an array of fill values
* can be passed.
*/
/** @typedef {import("./geotiff.js").TypedArray} TypedArray */
/** @typedef {import("./geotiff.js").ReadRasterResult} ReadRasterResult */
function sum(array, start, end) {
let s = 0;
for (let i = start; i < end; ++i) {
s += array[i];
}
return s;
}
function arrayForType(format, bitsPerSample, size) {
switch (format) {
case 1: // unsigned integer data
if (bitsPerSample <= 8) {
return new Uint8Array(size);
} else if (bitsPerSample <= 16) {
return new Uint16Array(size);
} else if (bitsPerSample <= 32) {
return new Uint32Array(size);
}
break;
case 2: // twos complement signed integer data
if (bitsPerSample === 8) {
return new Int8Array(size);
} else if (bitsPerSample === 16) {
return new Int16Array(size);
} else if (bitsPerSample === 32) {
return new Int32Array(size);
}
break;
case 3: // floating point data
switch (bitsPerSample) {
case 16:
case 32:
return new Float32Array(size);
case 64:
return new Float64Array(size);
default:
break;
}
break;
default:
break;
}
throw Error('Unsupported data format/bitsPerSample');
}
function needsNormalization(format, bitsPerSample) {
if ((format === 1 || format === 2) && bitsPerSample <= 32 && bitsPerSample % 8 === 0) {
return false;
} else if (format === 3 && (bitsPerSample === 16 || bitsPerSample === 32 || bitsPerSample === 64)) {
return false;
}
return true;
}
function normalizeArray(inBuffer, format, planarConfiguration, samplesPerPixel, bitsPerSample, tileWidth, tileHeight) {
// const inByteArray = new Uint8Array(inBuffer);
const view = new DataView(inBuffer);
const outSize = planarConfiguration === 2
? tileHeight * tileWidth
: tileHeight * tileWidth * samplesPerPixel;
const samplesToTransfer = planarConfiguration === 2
? 1 : samplesPerPixel;
const outArray = arrayForType(format, bitsPerSample, outSize);
// let pixel = 0;
const bitMask = parseInt('1'.repeat(bitsPerSample), 2);
if (format === 1) { // unsigned integer
// translation of https://github.com/OSGeo/gdal/blob/master/gdal/frmts/gtiff/geotiff.cpp#L7337
let pixelBitSkip;
// let sampleBitOffset = 0;
if (planarConfiguration === 1) {
pixelBitSkip = samplesPerPixel * bitsPerSample;
// sampleBitOffset = (samplesPerPixel - 1) * bitsPerSample;
} else {
pixelBitSkip = bitsPerSample;
}
// Bits per line rounds up to next byte boundary.
let bitsPerLine = tileWidth * pixelBitSkip;
if ((bitsPerLine & 7) !== 0) {
bitsPerLine = (bitsPerLine + 7) & (~7);
}
for (let y = 0; y < tileHeight; ++y) {
const lineBitOffset = y * bitsPerLine;
for (let x = 0; x < tileWidth; ++x) {
const pixelBitOffset = lineBitOffset + (x * samplesToTransfer * bitsPerSample);
for (let i = 0; i < samplesToTransfer; ++i) {
const bitOffset = pixelBitOffset + (i * bitsPerSample);
const outIndex = (((y * tileWidth) + x) * samplesToTransfer) + i;
const byteOffset = Math.floor(bitOffset / 8);
const innerBitOffset = bitOffset % 8;
if (innerBitOffset + bitsPerSample <= 8) {
outArray[outIndex] = (view.getUint8(byteOffset) >> (8 - bitsPerSample) - innerBitOffset) & bitMask;
} else if (innerBitOffset + bitsPerSample <= 16) {
outArray[outIndex] = (view.getUint16(byteOffset) >> (16 - bitsPerSample) - innerBitOffset) & bitMask;
} else if (innerBitOffset + bitsPerSample <= 24) {
const raw = (view.getUint16(byteOffset) << 8) | (view.getUint8(byteOffset + 2));
outArray[outIndex] = (raw >> (24 - bitsPerSample) - innerBitOffset) & bitMask;
} else {
outArray[outIndex] = (view.getUint32(byteOffset) >> (32 - bitsPerSample) - innerBitOffset) & bitMask;
}
// let outWord = 0;
// for (let bit = 0; bit < bitsPerSample; ++bit) {
// if (inByteArray[bitOffset >> 3]
// & (0x80 >> (bitOffset & 7))) {
// outWord |= (1 << (bitsPerSample - 1 - bit));
// }
// ++bitOffset;
// }
// outArray[outIndex] = outWord;
// outArray[pixel] = outWord;
// pixel += 1;
}
// bitOffset = bitOffset + pixelBitSkip - bitsPerSample;
}
}
} else if (format === 3) { // floating point
// Float16 is handled elsewhere
// normalize 16/24 bit floats to 32 bit floats in the array
// console.time();
// if (bitsPerSample === 16) {
// for (let byte = 0, outIndex = 0; byte < inBuffer.byteLength; byte += 2, ++outIndex) {
// outArray[outIndex] = getFloat16(view, byte);
// }
// }
// console.timeEnd()
}
return outArray.buffer;
}
/**
* GeoTIFF sub-file image.
*/
class GeoTIFFImage {
/**
* @constructor
* @param {Object} fileDirectory The parsed file directory
* @param {Object} geoKeys The parsed geo-keys
* @param {DataView} dataView The DataView for the underlying file.
* @param {Boolean} littleEndian Whether the file is encoded in little or big endian
* @param {Boolean} cache Whether or not decoded tiles shall be cached
* @param {import('./source/basesource').BaseSource} source The datasource to read from
*/
constructor(fileDirectory, geoKeys, dataView, littleEndian, cache, source) {
this.fileDirectory = fileDirectory;
this.geoKeys = geoKeys;
this.dataView = dataView;
this.littleEndian = littleEndian;
this.tiles = cache ? {} : null;
this.isTiled = !fileDirectory.StripOffsets;
const planarConfiguration = fileDirectory.PlanarConfiguration;
this.planarConfiguration = (typeof planarConfiguration === 'undefined') ? 1 : planarConfiguration;
if (this.planarConfiguration !== 1 && this.planarConfiguration !== 2) {
throw new Error('Invalid planar configuration.');
}
this.source = source;
}
/**
* Returns the associated parsed file directory.
* @returns {Object} the parsed file directory
*/
getFileDirectory() {
return this.fileDirectory;
}
/**
* Returns the associated parsed geo keys.
* @returns {Object} the parsed geo keys
*/
getGeoKeys() {
return this.geoKeys;
}
/**
* Returns the width of the image.
* @returns {Number} the width of the image
*/
getWidth() {
return this.fileDirectory.ImageWidth;
}
/**
* Returns the height of the image.
* @returns {Number} the height of the image
*/
getHeight() {
return this.fileDirectory.ImageLength;
}
/**
* Returns the number of samples per pixel.
* @returns {Number} the number of samples per pixel
*/
getSamplesPerPixel() {
return typeof this.fileDirectory.SamplesPerPixel !== 'undefined'
? this.fileDirectory.SamplesPerPixel : 1;
}
/**
* Returns the width of each tile.
* @returns {Number} the width of each tile
*/
getTileWidth() {
return this.isTiled ? this.fileDirectory.TileWidth : this.getWidth();
}
/**
* Returns the height of each tile.
* @returns {Number} the height of each tile
*/
getTileHeight() {
if (this.isTiled) {
return this.fileDirectory.TileLength;
}
if (typeof this.fileDirectory.RowsPerStrip !== 'undefined') {
return Math.min(this.fileDirectory.RowsPerStrip, this.getHeight());
}
return this.getHeight();
}
getBlockWidth() {
return this.getTileWidth();
}
getBlockHeight(y) {
if (this.isTiled || (y + 1) * this.getTileHeight() <= this.getHeight()) {
return this.getTileHeight();
} else {
return this.getHeight() - (y * this.getTileHeight());
}
}
/**
* Calculates the number of bytes for each pixel across all samples. Only full
* bytes are supported, an exception is thrown when this is not the case.
* @returns {Number} the bytes per pixel
*/
getBytesPerPixel() {
let bytes = 0;
for (let i = 0; i < this.fileDirectory.BitsPerSample.length; ++i) {
bytes += this.getSampleByteSize(i);
}
return bytes;
}
getSampleByteSize(i) {
if (i >= this.fileDirectory.BitsPerSample.length) {
throw new RangeError(`Sample index ${i} is out of range.`);
}
return Math.ceil(this.fileDirectory.BitsPerSample[i] / 8);
}
getReaderForSample(sampleIndex) {
const format = this.fileDirectory.SampleFormat
? this.fileDirectory.SampleFormat[sampleIndex] : 1;
const bitsPerSample = this.fileDirectory.BitsPerSample[sampleIndex];
switch (format) {
case 1: // unsigned integer data
if (bitsPerSample <= 8) {
return DataView.prototype.getUint8;
} else if (bitsPerSample <= 16) {
return DataView.prototype.getUint16;
} else if (bitsPerSample <= 32) {
return DataView.prototype.getUint32;
}
break;
case 2: // twos complement signed integer data
if (bitsPerSample <= 8) {
return DataView.prototype.getInt8;
} else if (bitsPerSample <= 16) {
return DataView.prototype.getInt16;
} else if (bitsPerSample <= 32) {
return DataView.prototype.getInt32;
}
break;
case 3:
switch (bitsPerSample) {
case 16:
return function (offset, littleEndian) {
return getFloat16(this, offset, littleEndian);
};
case 32:
return DataView.prototype.getFloat32;
case 64:
return DataView.prototype.getFloat64;
default:
break;
}
break;
default:
break;
}
throw Error('Unsupported data format/bitsPerSample');
}
getSampleFormat(sampleIndex = 0) {
return this.fileDirectory.SampleFormat
? this.fileDirectory.SampleFormat[sampleIndex] : 1;
}
getBitsPerSample(sampleIndex = 0) {
return this.fileDirectory.BitsPerSample[sampleIndex];
}
getArrayForSample(sampleIndex, size) {
const format = this.getSampleFormat(sampleIndex);
const bitsPerSample = this.getBitsPerSample(sampleIndex);
return arrayForType(format, bitsPerSample, size);
}
/**
* Returns the decoded strip or tile.
* @param {Number} x the strip or tile x-offset
* @param {Number} y the tile y-offset (0 for stripped images)
* @param {Number} sample the sample to get for separated samples
* @param {import("./geotiff").Pool|import("./geotiff").BaseDecoder} poolOrDecoder the decoder or decoder pool
* @param {AbortSignal} [signal] An AbortSignal that may be signalled if the request is
* to be aborted
* @returns {Promise.<ArrayBuffer>}
*/
async getTileOrStrip(x, y, sample, poolOrDecoder, signal) {
const numTilesPerRow = Math.ceil(this.getWidth() / this.getTileWidth());
const numTilesPerCol = Math.ceil(this.getHeight() / this.getTileHeight());
let index;
const { tiles } = this;
if (this.planarConfiguration === 1) {
index = (y * numTilesPerRow) + x;
} else if (this.planarConfiguration === 2) {
index = (sample * numTilesPerRow * numTilesPerCol) + (y * numTilesPerRow) + x;
}
let offset;
let byteCount;
if (this.isTiled) {
offset = this.fileDirectory.TileOffsets[index];
byteCount = this.fileDirectory.TileByteCounts[index];
} else {
offset = this.fileDirectory.StripOffsets[index];
byteCount = this.fileDirectory.StripByteCounts[index];
}
const slice = (await this.source.fetch([{ offset, length: byteCount }], signal))[0];
let request;
if (tiles === null || !tiles[index]) {
// resolve each request by potentially applying array normalization
request = (async () => {
let data = await poolOrDecoder.decode(this.fileDirectory, slice);
const sampleFormat = this.getSampleFormat();
const bitsPerSample = this.getBitsPerSample();
if (needsNormalization(sampleFormat, bitsPerSample)) {
data = normalizeArray(
data,
sampleFormat,
this.planarConfiguration,
this.getSamplesPerPixel(),
bitsPerSample,
this.getTileWidth(),
this.getBlockHeight(y),
);
}
return data;
})();
// set the cache
if (tiles !== null) {
tiles[index] = request;
}
} else {
// get from the cache
request = tiles[index];
}
// cache the tile request
return { x, y, sample, data: await request };
}
/**
* Internal read function.
* @private
* @param {Array} imageWindow The image window in pixel coordinates
* @param {Array} samples The selected samples (0-based indices)
* @param {TypedArray|TypedArray[]} valueArrays The array(s) to write into
* @param {Boolean} interleave Whether or not to write in an interleaved manner
* @param {import("./geotiff").Pool|AbstractDecoder} poolOrDecoder the decoder or decoder pool
* @param {number} width the width of window to be read into
* @param {number} height the height of window to be read into
* @param {number} resampleMethod the resampling method to be used when interpolating
* @param {AbortSignal} [signal] An AbortSignal that may be signalled if the request is
* to be aborted
* @returns {Promise<ReadRasterResult>}
*/
async _readRaster(imageWindow, samples, valueArrays, interleave, poolOrDecoder, width,
height, resampleMethod, signal) {
const tileWidth = this.getTileWidth();
const tileHeight = this.getTileHeight();
const imageWidth = this.getWidth();
const imageHeight = this.getHeight();
const minXTile = Math.max(Math.floor(imageWindow[0] / tileWidth), 0);
const maxXTile = Math.min(
Math.ceil(imageWindow[2] / tileWidth),
Math.ceil(imageWidth / tileWidth),
);
const minYTile = Math.max(Math.floor(imageWindow[1] / tileHeight), 0);
const maxYTile = Math.min(
Math.ceil(imageWindow[3] / tileHeight),
Math.ceil(imageHeight / tileHeight),
);
const windowWidth = imageWindow[2] - imageWindow[0];
let bytesPerPixel = this.getBytesPerPixel();
const srcSampleOffsets = [];
const sampleReaders = [];
for (let i = 0; i < samples.length; ++i) {
if (this.planarConfiguration === 1) {
srcSampleOffsets.push(sum(this.fileDirectory.BitsPerSample, 0, samples[i]) / 8);
} else {
srcSampleOffsets.push(0);
}
sampleReaders.push(this.getReaderForSample(samples[i]));
}
const promises = [];
const { littleEndian } = this;
for (let yTile = minYTile; yTile < maxYTile; ++yTile) {
for (let xTile = minXTile; xTile < maxXTile; ++xTile) {
let getPromise;
if (this.planarConfiguration === 1) {
getPromise = this.getTileOrStrip(xTile, yTile, 0, poolOrDecoder, signal);
}
for (let sampleIndex = 0; sampleIndex < samples.length; ++sampleIndex) {
const si = sampleIndex;
const sample = samples[sampleIndex];
if (this.planarConfiguration === 2) {
bytesPerPixel = this.getSampleByteSize(sample);
getPromise = this.getTileOrStrip(xTile, yTile, sample, poolOrDecoder, signal);
}
const promise = getPromise.then((tile) => {
const buffer = tile.data;
const dataView = new DataView(buffer);
const blockHeight = this.getBlockHeight(tile.y);
const firstLine = tile.y * tileHeight;
const firstCol = tile.x * tileWidth;
const lastLine = firstLine + blockHeight;
const lastCol = (tile.x + 1) * tileWidth;
const reader = sampleReaders[si];
const ymax = Math.min(blockHeight, blockHeight - (lastLine - imageWindow[3]), imageHeight - firstLine);
const xmax = Math.min(tileWidth, tileWidth - (lastCol - imageWindow[2]), imageWidth - firstCol);
for (let y = Math.max(0, imageWindow[1] - firstLine); y < ymax; ++y) {
for (let x = Math.max(0, imageWindow[0] - firstCol); x < xmax; ++x) {
const pixelOffset = ((y * tileWidth) + x) * bytesPerPixel;
const value = reader.call(
dataView, pixelOffset + srcSampleOffsets[si], littleEndian,
);
let windowCoordinate;
if (interleave) {
windowCoordinate = ((y + firstLine - imageWindow[1]) * windowWidth * samples.length)
+ ((x + firstCol - imageWindow[0]) * samples.length)
+ si;
valueArrays[windowCoordinate] = value;
} else {
windowCoordinate = (
(y + firstLine - imageWindow[1]) * windowWidth
) + x + firstCol - imageWindow[0];
valueArrays[si][windowCoordinate] = value;
}
}
}
});
promises.push(promise);
}
}
}
await Promise.all(promises);
if ((width && (imageWindow[2] - imageWindow[0]) !== width)
|| (height && (imageWindow[3] - imageWindow[1]) !== height)) {
let resampled;
if (interleave) {
resampled = resampleInterleaved(
valueArrays,
imageWindow[2] - imageWindow[0],
imageWindow[3] - imageWindow[1],
width, height,
samples.length,
resampleMethod,
);
} else {
resampled = resample(
valueArrays,
imageWindow[2] - imageWindow[0],
imageWindow[3] - imageWindow[1],
width, height,
resampleMethod,
);
}
resampled.width = width;
resampled.height = height;
return resampled;
}
valueArrays.width = width || imageWindow[2] - imageWindow[0];
valueArrays.height = height || imageWindow[3] - imageWindow[1];
return valueArrays;
}
/**
* Reads raster data from the image. This function reads all selected samples
* into separate arrays of the correct type for that sample or into a single
* combined array when `interleave` is set. When provided, only a subset
* of the raster is read for each sample.
*
* @param {ReadRasterOptions} [options={}] optional parameters
* @returns {Promise<ReadRasterResult>} the decoded arrays as a promise
*/
async readRasters({
window: wnd, samples = [], interleave, pool = null,
width, height, resampleMethod, fillValue, signal,
} = {}) {
const imageWindow = wnd || [0, 0, this.getWidth(), this.getHeight()];
// check parameters
if (imageWindow[0] > imageWindow[2] || imageWindow[1] > imageWindow[3]) {
throw new Error('Invalid subsets');
}
const imageWindowWidth = imageWindow[2] - imageWindow[0];
const imageWindowHeight = imageWindow[3] - imageWindow[1];
const numPixels = imageWindowWidth * imageWindowHeight;
const samplesPerPixel = this.getSamplesPerPixel();
if (!samples || !samples.length) {
for (let i = 0; i < samplesPerPixel; ++i) {
samples.push(i);
}
} else {
for (let i = 0; i < samples.length; ++i) {
if (samples[i] >= samplesPerPixel) {
return Promise.reject(new RangeError(`Invalid sample index '${samples[i]}'.`));
}
}
}
let valueArrays;
if (interleave) {
const format = this.fileDirectory.SampleFormat
? Math.max.apply(null, this.fileDirectory.SampleFormat) : 1;
const bitsPerSample = Math.max.apply(null, this.fileDirectory.BitsPerSample);
valueArrays = arrayForType(format, bitsPerSample, numPixels * samples.length);
if (fillValue) {
valueArrays.fill(fillValue);
}
} else {
valueArrays = [];
for (let i = 0; i < samples.length; ++i) {
const valueArray = this.getArrayForSample(samples[i], numPixels);
if (Array.isArray(fillValue) && i < fillValue.length) {
valueArray.fill(fillValue[i]);
} else if (fillValue && !Array.isArray(fillValue)) {
valueArray.fill(fillValue);
}
valueArrays.push(valueArray);
}
}
const poolOrDecoder = pool || await getDecoder(this.fileDirectory);
const result = await this._readRaster(
imageWindow, samples, valueArrays, interleave, poolOrDecoder, width, height, resampleMethod, signal,
);
return result;
}
/**
* Reads raster data from the image as RGB. The result is always an
* interleaved typed array.
* Colorspaces other than RGB will be transformed to RGB, color maps expanded.
* When no other method is applicable, the first sample is used to produce a
* grayscale image.
* When provided, only a subset of the raster is read for each sample.
*
* @param {Object} [options] optional parameters
* @param {Array<number>} [options.window] the subset to read data from in pixels.
* @param {boolean} [options.interleave=true] whether the data shall be read
* in one single array or separate
* arrays.
* @param {import("./geotiff").Pool} [options.pool=null] The optional decoder pool to use.
* @param {number} [options.width] The desired width of the output. When the width is no the
* same as the images, resampling will be performed.
* @param {number} [options.height] The desired height of the output. When the width is no the
* same as the images, resampling will be performed.
* @param {string} [options.resampleMethod='nearest'] The desired resampling method.
* @param {boolean} [options.enableAlpha=false] Enable reading alpha channel if present.
* @param {AbortSignal} [options.signal] An AbortSignal that may be signalled if the request is
* to be aborted
* @returns {Promise<ReadRasterResult>} the RGB array as a Promise
*/
async readRGB({ window, interleave = true, pool = null, width, height,
resampleMethod, enableAlpha = false, signal } = {}) {
const imageWindow = window || [0, 0, this.getWidth(), this.getHeight()];
// check parameters
if (imageWindow[0] > imageWindow[2] || imageWindow[1] > imageWindow[3]) {
throw new Error('Invalid subsets');
}
const pi = this.fileDirectory.PhotometricInterpretation;
if (pi === photometricInterpretations.RGB) {
let s = [0, 1, 2];
if ((!(this.fileDirectory.ExtraSamples === ExtraSamplesValues.Unspecified)) && enableAlpha) {
s = [];
for (let i = 0; i < this.fileDirectory.BitsPerSample.length; i += 1) {
s.push(i);
}
}
return this.readRasters({
window,
interleave,
samples: s,
pool,
width,
height,
resampleMethod,
signal,
});
}
let samples;
switch (pi) {
case photometricInterpretations.WhiteIsZero:
case photometricInterpretations.BlackIsZero:
case photometricInterpretations.Palette:
samples = [0];
break;
case photometricInterpretations.CMYK:
samples = [0, 1, 2, 3];
break;
case photometricInterpretations.YCbCr:
case photometricInterpretations.CIELab:
samples = [0, 1, 2];
break;
default:
throw new Error('Invalid or unsupported photometric interpretation.');
}
const subOptions = {
window: imageWindow,
interleave: true,
samples,
pool,
width,
height,
resampleMethod,
signal,
};
const { fileDirectory } = this;
const raster = await this.readRasters(subOptions);
const max = 2 ** this.fileDirectory.BitsPerSample[0];
let data;
switch (pi) {
case photometricInterpretations.WhiteIsZero:
data = fromWhiteIsZero(raster, max);
break;
case photometricInterpretations.BlackIsZero:
data = fromBlackIsZero(raster, max);
break;
case photometricInterpretations.Palette:
data = fromPalette(raster, fileDirectory.ColorMap);
break;
case photometricInterpretations.CMYK:
data = fromCMYK(raster);
break;
case photometricInterpretations.YCbCr:
data = fromYCbCr(raster);
break;
case photometricInterpretations.CIELab:
data = fromCIELab(raster);
break;
default:
throw new Error('Unsupported photometric interpretation.');
}
// if non-interleaved data is requested, we must split the channels
// into their respective arrays
if (!interleave) {
const red = new Uint8Array(data.length / 3);
const green = new Uint8Array(data.length / 3);
const blue = new Uint8Array(data.length / 3);
for (let i = 0, j = 0; i < data.length; i += 3, ++j) {
red[j] = data[i];
green[j] = data[i + 1];
blue[j] = data[i + 2];
}
data = [red, green, blue];
}
data.width = raster.width;
data.height = raster.height;
return data;
}
/**
* Returns an array of tiepoints.
* @returns {Object[]}
*/
getTiePoints() {
if (!this.fileDirectory.ModelTiepoint) {
return [];
}
const tiePoints = [];
for (let i = 0; i < this.fileDirectory.ModelTiepoint.length; i += 6) {
tiePoints.push({
i: this.fileDirectory.ModelTiepoint[i],
j: this.fileDirectory.ModelTiepoint[i + 1],
k: this.fileDirectory.ModelTiepoint[i + 2],
x: this.fileDirectory.ModelTiepoint[i + 3],
y: this.fileDirectory.ModelTiepoint[i + 4],
z: this.fileDirectory.ModelTiepoint[i + 5],
});
}
return tiePoints;
}
/**
* Returns the parsed GDAL metadata items.
*
* If sample is passed to null, dataset-level metadata will be returned.
* Otherwise only metadata specific to the provided sample will be returned.
*
* @param {number} [sample=null] The sample index.
* @returns {Object}
*/
getGDALMetadata(sample = null) {
const metadata = {};
if (!this.fileDirectory.GDAL_METADATA) {
return null;
}
const string = this.fileDirectory.GDAL_METADATA;
let items = findTagsByName(string, 'Item');
if (sample === null) {
items = items.filter((item) => getAttribute(item, 'sample') === undefined);
} else {
items = items.filter((item) => Number(getAttribute(item, 'sample')) === sample);
}
for (let i = 0; i < items.length; ++i) {
const item = items[i];
metadata[getAttribute(item, 'name')] = item.inner;
}
return metadata;
}
/**
* Returns the GDAL nodata value
* @returns {number|null}
*/
getGDALNoData() {
if (!this.fileDirectory.GDAL_NODATA) {
return null;
}
const string = this.fileDirectory.GDAL_NODATA;
return Number(string.substring(0, string.length - 1));
}
/**
* Returns the image origin as a XYZ-vector. When the image has no affine
* transformation, then an exception is thrown.
* @returns {Array<number>} The origin as a vector
*/
getOrigin() {
const tiePoints = this.fileDirectory.ModelTiepoint;
const modelTransformation = this.fileDirectory.ModelTransformation;
if (tiePoints && tiePoints.length === 6) {
return [
tiePoints[3],
tiePoints[4],
tiePoints[5],
];
}
if (modelTransformation) {
return [
modelTransformation[3],
modelTransformation[7],
modelTransformation[11],
];
}
throw new Error('The image does not have an affine transformation.');
}
/**
* Returns the image resolution as a XYZ-vector. When the image has no affine
* transformation, then an exception is thrown.
* @param {GeoTIFFImage} [referenceImage=null] A reference image to calculate the resolution from
* in cases when the current image does not have the
* required tags on its own.
* @returns {Array<number>} The resolution as a vector
*/
getResolution(referenceImage = null) {
const modelPixelScale = this.fileDirectory.ModelPixelScale;
const modelTransformation = this.fileDirectory.ModelTransformation;
if (modelPixelScale) {
return [
modelPixelScale[0],
-modelPixelScale[1],
modelPixelScale[2],
];
}
if (modelTransformation) {
if (modelTransformation[1] === 0 && modelTransformation[4] === 0) {
return [
modelTransformation[0],
-modelTransformation[5],
modelTransformation[10],
];
}
return [
Math.sqrt((modelTransformation[0] * modelTransformation[0])
+ (modelTransformation[4] * modelTransformation[4])),
-Math.sqrt((modelTransformation[1] * modelTransformation[1])
+ (modelTransformation[5] * modelTransformation[5])),
modelTransformation[10]];
}
if (referenceImage) {
const [refResX, refResY, refResZ] = referenceImage.getResolution();
return [
refResX * referenceImage.getWidth() / this.getWidth(),
refResY * referenceImage.getHeight() / this.getHeight(),
refResZ * referenceImage.getWidth() / this.getWidth(),
];
}
throw new Error('The image does not have an affine transformation.');
}
/**
* Returns whether or not the pixels of the image depict an area (or point).
* @returns {Boolean} Whether the pixels are a point
*/
pixelIsArea() {
return this.geoKeys.GTRasterTypeGeoKey === 1;
}
/**
* Returns the image bounding box as an array of 4 values: min-x, min-y,
* max-x and max-y. When the image has no affine transformation, then an
* exception is thrown.
* @param {boolean} [tilegrid=false] If true return extent for a tilegrid
* without adjustment for ModelTransformation.
* @returns {Array<number>} The bounding box
*/
getBoundingBox(tilegrid = false) {
const height = this.getHeight();
const width = this.getWidth();
if (this.fileDirectory.ModelTransformation && !tilegrid) {
// eslint-disable-next-line no-unused-vars
const [a, b, c, d, e, f, g, h] = this.fileDirectory.ModelTransformation;
const corners = [
[0, 0],
[0, height],
[width, 0],
[width, height],
];
const projected = corners.map(([I, J]) => [
d + (a * I) + (b * J),
h + (e * I) + (f * J),
]);
const xs = projected.map((pt) => pt[0]);
const ys = projected.map((pt) => pt[1]);
return [
Math.min(...xs),
Math.min(...ys),
Math.max(...xs),
Math.max(...ys),
];
} else {
const origin = this.getOrigin();
const resolution = this.getResolution();
const x1 = origin[0];
const y1 = origin[1];
const x2 = x1 + (resolution[0] * width);
const y2 = y1 + (resolution[1] * height);
return [
Math.min(x1, x2),
Math.min(y1, y2),
Math.max(x1, x2),
Math.max(y1, y2),
];
}
}
}
export default GeoTIFFImage;