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- // Copyright 2013 Lovell Fuller and others.
- // SPDX-License-Identifier: Apache-2.0
- 'use strict';
- const color = require('color');
- const is = require('./is');
- /**
- * Rotate the output image by either an explicit angle
- * or auto-orient based on the EXIF `Orientation` tag.
- *
- * If an angle is provided, it is converted to a valid positive degree rotation.
- * For example, `-450` will produce a 270 degree rotation.
- *
- * When rotating by an angle other than a multiple of 90,
- * the background colour can be provided with the `background` option.
- *
- * If no angle is provided, it is determined from the EXIF data.
- * Mirroring is supported and may infer the use of a flip operation.
- *
- * The use of `rotate` without an angle will remove the EXIF `Orientation` tag, if any.
- *
- * Only one rotation can occur per pipeline.
- * Previous calls to `rotate` in the same pipeline will be ignored.
- *
- * Method order is important when rotating, resizing and/or extracting regions,
- * for example `.rotate(x).extract(y)` will produce a different result to `.extract(y).rotate(x)`.
- *
- * @example
- * const pipeline = sharp()
- * .rotate()
- * .resize(null, 200)
- * .toBuffer(function (err, outputBuffer, info) {
- * // outputBuffer contains 200px high JPEG image data,
- * // auto-rotated using EXIF Orientation tag
- * // info.width and info.height contain the dimensions of the resized image
- * });
- * readableStream.pipe(pipeline);
- *
- * @example
- * const rotateThenResize = await sharp(input)
- * .rotate(90)
- * .resize({ width: 16, height: 8, fit: 'fill' })
- * .toBuffer();
- * const resizeThenRotate = await sharp(input)
- * .resize({ width: 16, height: 8, fit: 'fill' })
- * .rotate(90)
- * .toBuffer();
- *
- * @param {number} [angle=auto] angle of rotation.
- * @param {Object} [options] - if present, is an Object with optional attributes.
- * @param {string|Object} [options.background="#000000"] parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function rotate (angle, options) {
- if (this.options.useExifOrientation || this.options.angle || this.options.rotationAngle) {
- this.options.debuglog('ignoring previous rotate options');
- }
- if (!is.defined(angle)) {
- this.options.useExifOrientation = true;
- } else if (is.integer(angle) && !(angle % 90)) {
- this.options.angle = angle;
- } else if (is.number(angle)) {
- this.options.rotationAngle = angle;
- if (is.object(options) && options.background) {
- const backgroundColour = color(options.background);
- this.options.rotationBackground = [
- backgroundColour.red(),
- backgroundColour.green(),
- backgroundColour.blue(),
- Math.round(backgroundColour.alpha() * 255)
- ];
- }
- } else {
- throw is.invalidParameterError('angle', 'numeric', angle);
- }
- return this;
- }
- /**
- * Mirror the image vertically (up-down) about the x-axis.
- * This always occurs before rotation, if any.
- *
- * This operation does not work correctly with multi-page images.
- *
- * @example
- * const output = await sharp(input).flip().toBuffer();
- *
- * @param {Boolean} [flip=true]
- * @returns {Sharp}
- */
- function flip (flip) {
- this.options.flip = is.bool(flip) ? flip : true;
- return this;
- }
- /**
- * Mirror the image horizontally (left-right) about the y-axis.
- * This always occurs before rotation, if any.
- *
- * @example
- * const output = await sharp(input).flop().toBuffer();
- *
- * @param {Boolean} [flop=true]
- * @returns {Sharp}
- */
- function flop (flop) {
- this.options.flop = is.bool(flop) ? flop : true;
- return this;
- }
- /**
- * Perform an affine transform on an image. This operation will always occur after resizing, extraction and rotation, if any.
- *
- * You must provide an array of length 4 or a 2x2 affine transformation matrix.
- * By default, new pixels are filled with a black background. You can provide a background color with the `background` option.
- * A particular interpolator may also be specified. Set the `interpolator` option to an attribute of the `sharp.interpolators` Object e.g. `sharp.interpolators.nohalo`.
- *
- * In the case of a 2x2 matrix, the transform is:
- * - X = `matrix[0, 0]` \* (x + `idx`) + `matrix[0, 1]` \* (y + `idy`) + `odx`
- * - Y = `matrix[1, 0]` \* (x + `idx`) + `matrix[1, 1]` \* (y + `idy`) + `ody`
- *
- * where:
- * - x and y are the coordinates in input image.
- * - X and Y are the coordinates in output image.
- * - (0,0) is the upper left corner.
- *
- * @since 0.27.0
- *
- * @example
- * const pipeline = sharp()
- * .affine([[1, 0.3], [0.1, 0.7]], {
- * background: 'white',
- * interpolator: sharp.interpolators.nohalo
- * })
- * .toBuffer((err, outputBuffer, info) => {
- * // outputBuffer contains the transformed image
- * // info.width and info.height contain the new dimensions
- * });
- *
- * inputStream
- * .pipe(pipeline);
- *
- * @param {Array<Array<number>>|Array<number>} matrix - affine transformation matrix
- * @param {Object} [options] - if present, is an Object with optional attributes.
- * @param {String|Object} [options.background="#000000"] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
- * @param {Number} [options.idx=0] - input horizontal offset
- * @param {Number} [options.idy=0] - input vertical offset
- * @param {Number} [options.odx=0] - output horizontal offset
- * @param {Number} [options.ody=0] - output vertical offset
- * @param {String} [options.interpolator=sharp.interpolators.bicubic] - interpolator
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function affine (matrix, options) {
- const flatMatrix = [].concat(...matrix);
- if (flatMatrix.length === 4 && flatMatrix.every(is.number)) {
- this.options.affineMatrix = flatMatrix;
- } else {
- throw is.invalidParameterError('matrix', '1x4 or 2x2 array', matrix);
- }
- if (is.defined(options)) {
- if (is.object(options)) {
- this._setBackgroundColourOption('affineBackground', options.background);
- if (is.defined(options.idx)) {
- if (is.number(options.idx)) {
- this.options.affineIdx = options.idx;
- } else {
- throw is.invalidParameterError('options.idx', 'number', options.idx);
- }
- }
- if (is.defined(options.idy)) {
- if (is.number(options.idy)) {
- this.options.affineIdy = options.idy;
- } else {
- throw is.invalidParameterError('options.idy', 'number', options.idy);
- }
- }
- if (is.defined(options.odx)) {
- if (is.number(options.odx)) {
- this.options.affineOdx = options.odx;
- } else {
- throw is.invalidParameterError('options.odx', 'number', options.odx);
- }
- }
- if (is.defined(options.ody)) {
- if (is.number(options.ody)) {
- this.options.affineOdy = options.ody;
- } else {
- throw is.invalidParameterError('options.ody', 'number', options.ody);
- }
- }
- if (is.defined(options.interpolator)) {
- if (is.inArray(options.interpolator, Object.values(this.constructor.interpolators))) {
- this.options.affineInterpolator = options.interpolator;
- } else {
- throw is.invalidParameterError('options.interpolator', 'valid interpolator name', options.interpolator);
- }
- }
- } else {
- throw is.invalidParameterError('options', 'object', options);
- }
- }
- return this;
- }
- /**
- * Sharpen the image.
- *
- * When used without parameters, performs a fast, mild sharpen of the output image.
- *
- * When a `sigma` is provided, performs a slower, more accurate sharpen of the L channel in the LAB colour space.
- * Fine-grained control over the level of sharpening in "flat" (m1) and "jagged" (m2) areas is available.
- *
- * See {@link https://www.libvips.org/API/current/libvips-convolution.html#vips-sharpen|libvips sharpen} operation.
- *
- * @example
- * const data = await sharp(input).sharpen().toBuffer();
- *
- * @example
- * const data = await sharp(input).sharpen({ sigma: 2 }).toBuffer();
- *
- * @example
- * const data = await sharp(input)
- * .sharpen({
- * sigma: 2,
- * m1: 0,
- * m2: 3,
- * x1: 3,
- * y2: 15,
- * y3: 15,
- * })
- * .toBuffer();
- *
- * @param {Object|number} [options] - if present, is an Object with attributes
- * @param {number} [options.sigma] - the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`, between 0.000001 and 10
- * @param {number} [options.m1=1.0] - the level of sharpening to apply to "flat" areas, between 0 and 1000000
- * @param {number} [options.m2=2.0] - the level of sharpening to apply to "jagged" areas, between 0 and 1000000
- * @param {number} [options.x1=2.0] - threshold between "flat" and "jagged", between 0 and 1000000
- * @param {number} [options.y2=10.0] - maximum amount of brightening, between 0 and 1000000
- * @param {number} [options.y3=20.0] - maximum amount of darkening, between 0 and 1000000
- * @param {number} [flat] - (deprecated) see `options.m1`.
- * @param {number} [jagged] - (deprecated) see `options.m2`.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function sharpen (options, flat, jagged) {
- if (!is.defined(options)) {
- // No arguments: default to mild sharpen
- this.options.sharpenSigma = -1;
- } else if (is.bool(options)) {
- // Deprecated boolean argument: apply mild sharpen?
- this.options.sharpenSigma = options ? -1 : 0;
- } else if (is.number(options) && is.inRange(options, 0.01, 10000)) {
- // Deprecated numeric argument: specific sigma
- this.options.sharpenSigma = options;
- // Deprecated control over flat areas
- if (is.defined(flat)) {
- if (is.number(flat) && is.inRange(flat, 0, 10000)) {
- this.options.sharpenM1 = flat;
- } else {
- throw is.invalidParameterError('flat', 'number between 0 and 10000', flat);
- }
- }
- // Deprecated control over jagged areas
- if (is.defined(jagged)) {
- if (is.number(jagged) && is.inRange(jagged, 0, 10000)) {
- this.options.sharpenM2 = jagged;
- } else {
- throw is.invalidParameterError('jagged', 'number between 0 and 10000', jagged);
- }
- }
- } else if (is.plainObject(options)) {
- if (is.number(options.sigma) && is.inRange(options.sigma, 0.000001, 10)) {
- this.options.sharpenSigma = options.sigma;
- } else {
- throw is.invalidParameterError('options.sigma', 'number between 0.000001 and 10', options.sigma);
- }
- if (is.defined(options.m1)) {
- if (is.number(options.m1) && is.inRange(options.m1, 0, 1000000)) {
- this.options.sharpenM1 = options.m1;
- } else {
- throw is.invalidParameterError('options.m1', 'number between 0 and 1000000', options.m1);
- }
- }
- if (is.defined(options.m2)) {
- if (is.number(options.m2) && is.inRange(options.m2, 0, 1000000)) {
- this.options.sharpenM2 = options.m2;
- } else {
- throw is.invalidParameterError('options.m2', 'number between 0 and 1000000', options.m2);
- }
- }
- if (is.defined(options.x1)) {
- if (is.number(options.x1) && is.inRange(options.x1, 0, 1000000)) {
- this.options.sharpenX1 = options.x1;
- } else {
- throw is.invalidParameterError('options.x1', 'number between 0 and 1000000', options.x1);
- }
- }
- if (is.defined(options.y2)) {
- if (is.number(options.y2) && is.inRange(options.y2, 0, 1000000)) {
- this.options.sharpenY2 = options.y2;
- } else {
- throw is.invalidParameterError('options.y2', 'number between 0 and 1000000', options.y2);
- }
- }
- if (is.defined(options.y3)) {
- if (is.number(options.y3) && is.inRange(options.y3, 0, 1000000)) {
- this.options.sharpenY3 = options.y3;
- } else {
- throw is.invalidParameterError('options.y3', 'number between 0 and 1000000', options.y3);
- }
- }
- } else {
- throw is.invalidParameterError('sigma', 'number between 0.01 and 10000', options);
- }
- return this;
- }
- /**
- * Apply median filter.
- * When used without parameters the default window is 3x3.
- *
- * @example
- * const output = await sharp(input).median().toBuffer();
- *
- * @example
- * const output = await sharp(input).median(5).toBuffer();
- *
- * @param {number} [size=3] square mask size: size x size
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function median (size) {
- if (!is.defined(size)) {
- // No arguments: default to 3x3
- this.options.medianSize = 3;
- } else if (is.integer(size) && is.inRange(size, 1, 1000)) {
- // Numeric argument: specific sigma
- this.options.medianSize = size;
- } else {
- throw is.invalidParameterError('size', 'integer between 1 and 1000', size);
- }
- return this;
- }
- /**
- * Blur the image.
- *
- * When used without parameters, performs a fast 3x3 box blur (equivalent to a box linear filter).
- *
- * When a `sigma` is provided, performs a slower, more accurate Gaussian blur.
- *
- * @example
- * const boxBlurred = await sharp(input)
- * .blur()
- * .toBuffer();
- *
- * @example
- * const gaussianBlurred = await sharp(input)
- * .blur(5)
- * .toBuffer();
- *
- * @param {number} [sigma] a value between 0.3 and 1000 representing the sigma of the Gaussian mask, where `sigma = 1 + radius / 2`.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function blur (sigma) {
- if (!is.defined(sigma)) {
- // No arguments: default to mild blur
- this.options.blurSigma = -1;
- } else if (is.bool(sigma)) {
- // Boolean argument: apply mild blur?
- this.options.blurSigma = sigma ? -1 : 0;
- } else if (is.number(sigma) && is.inRange(sigma, 0.3, 1000)) {
- // Numeric argument: specific sigma
- this.options.blurSigma = sigma;
- } else {
- throw is.invalidParameterError('sigma', 'number between 0.3 and 1000', sigma);
- }
- return this;
- }
- /**
- * Merge alpha transparency channel, if any, with a background, then remove the alpha channel.
- *
- * See also {@link /api-channel#removealpha|removeAlpha}.
- *
- * @example
- * await sharp(rgbaInput)
- * .flatten({ background: '#F0A703' })
- * .toBuffer();
- *
- * @param {Object} [options]
- * @param {string|Object} [options.background={r: 0, g: 0, b: 0}] - background colour, parsed by the [color](https://www.npmjs.org/package/color) module, defaults to black.
- * @returns {Sharp}
- */
- function flatten (options) {
- this.options.flatten = is.bool(options) ? options : true;
- if (is.object(options)) {
- this._setBackgroundColourOption('flattenBackground', options.background);
- }
- return this;
- }
- /**
- * Ensure the image has an alpha channel
- * with all white pixel values made fully transparent.
- *
- * Existing alpha channel values for non-white pixels remain unchanged.
- *
- * This feature is experimental and the API may change.
- *
- * @since 0.32.1
- *
- * @example
- * await sharp(rgbInput)
- * .unflatten()
- * .toBuffer();
- *
- * @example
- * await sharp(rgbInput)
- * .threshold(128, { grayscale: false }) // converter bright pixels to white
- * .unflatten()
- * .toBuffer();
- */
- function unflatten () {
- this.options.unflatten = true;
- return this;
- }
- /**
- * Apply a gamma correction by reducing the encoding (darken) pre-resize at a factor of `1/gamma`
- * then increasing the encoding (brighten) post-resize at a factor of `gamma`.
- * This can improve the perceived brightness of a resized image in non-linear colour spaces.
- * JPEG and WebP input images will not take advantage of the shrink-on-load performance optimisation
- * when applying a gamma correction.
- *
- * Supply a second argument to use a different output gamma value, otherwise the first value is used in both cases.
- *
- * @param {number} [gamma=2.2] value between 1.0 and 3.0.
- * @param {number} [gammaOut] value between 1.0 and 3.0. (optional, defaults to same as `gamma`)
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function gamma (gamma, gammaOut) {
- if (!is.defined(gamma)) {
- // Default gamma correction of 2.2 (sRGB)
- this.options.gamma = 2.2;
- } else if (is.number(gamma) && is.inRange(gamma, 1, 3)) {
- this.options.gamma = gamma;
- } else {
- throw is.invalidParameterError('gamma', 'number between 1.0 and 3.0', gamma);
- }
- if (!is.defined(gammaOut)) {
- // Default gamma correction for output is same as input
- this.options.gammaOut = this.options.gamma;
- } else if (is.number(gammaOut) && is.inRange(gammaOut, 1, 3)) {
- this.options.gammaOut = gammaOut;
- } else {
- throw is.invalidParameterError('gammaOut', 'number between 1.0 and 3.0', gammaOut);
- }
- return this;
- }
- /**
- * Produce the "negative" of the image.
- *
- * @example
- * const output = await sharp(input)
- * .negate()
- * .toBuffer();
- *
- * @example
- * const output = await sharp(input)
- * .negate({ alpha: false })
- * .toBuffer();
- *
- * @param {Object} [options]
- * @param {Boolean} [options.alpha=true] Whether or not to negate any alpha channel
- * @returns {Sharp}
- */
- function negate (options) {
- this.options.negate = is.bool(options) ? options : true;
- if (is.plainObject(options) && 'alpha' in options) {
- if (!is.bool(options.alpha)) {
- throw is.invalidParameterError('alpha', 'should be boolean value', options.alpha);
- } else {
- this.options.negateAlpha = options.alpha;
- }
- }
- return this;
- }
- /**
- * Enhance output image contrast by stretching its luminance to cover a full dynamic range.
- *
- * Uses a histogram-based approach, taking a default range of 1% to 99% to reduce sensitivity to noise at the extremes.
- *
- * Luminance values below the `lower` percentile will be underexposed by clipping to zero.
- * Luminance values above the `upper` percentile will be overexposed by clipping to the max pixel value.
- *
- * @example
- * const output = await sharp(input)
- * .normalise()
- * .toBuffer();
- *
- * @example
- * const output = await sharp(input)
- * .normalise({ lower: 0, upper: 100 })
- * .toBuffer();
- *
- * @param {Object} [options]
- * @param {number} [options.lower=1] - Percentile below which luminance values will be underexposed.
- * @param {number} [options.upper=99] - Percentile above which luminance values will be overexposed.
- * @returns {Sharp}
- */
- function normalise (options) {
- if (is.plainObject(options)) {
- if (is.defined(options.lower)) {
- if (is.number(options.lower) && is.inRange(options.lower, 0, 99)) {
- this.options.normaliseLower = options.lower;
- } else {
- throw is.invalidParameterError('lower', 'number between 0 and 99', options.lower);
- }
- }
- if (is.defined(options.upper)) {
- if (is.number(options.upper) && is.inRange(options.upper, 1, 100)) {
- this.options.normaliseUpper = options.upper;
- } else {
- throw is.invalidParameterError('upper', 'number between 1 and 100', options.upper);
- }
- }
- }
- if (this.options.normaliseLower >= this.options.normaliseUpper) {
- throw is.invalidParameterError('range', 'lower to be less than upper',
- `${this.options.normaliseLower} >= ${this.options.normaliseUpper}`);
- }
- this.options.normalise = true;
- return this;
- }
- /**
- * Alternative spelling of normalise.
- *
- * @example
- * const output = await sharp(input)
- * .normalize()
- * .toBuffer();
- *
- * @param {Object} [options]
- * @param {number} [options.lower=1] - Percentile below which luminance values will be underexposed.
- * @param {number} [options.upper=99] - Percentile above which luminance values will be overexposed.
- * @returns {Sharp}
- */
- function normalize (options) {
- return this.normalise(options);
- }
- /**
- * Perform contrast limiting adaptive histogram equalization
- * {@link https://en.wikipedia.org/wiki/Adaptive_histogram_equalization#Contrast_Limited_AHE|CLAHE}.
- *
- * This will, in general, enhance the clarity of the image by bringing out darker details.
- *
- * @since 0.28.3
- *
- * @example
- * const output = await sharp(input)
- * .clahe({
- * width: 3,
- * height: 3,
- * })
- * .toBuffer();
- *
- * @param {Object} options
- * @param {number} options.width - Integral width of the search window, in pixels.
- * @param {number} options.height - Integral height of the search window, in pixels.
- * @param {number} [options.maxSlope=3] - Integral level of brightening, between 0 and 100, where 0 disables contrast limiting.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function clahe (options) {
- if (is.plainObject(options)) {
- if (is.integer(options.width) && options.width > 0) {
- this.options.claheWidth = options.width;
- } else {
- throw is.invalidParameterError('width', 'integer greater than zero', options.width);
- }
- if (is.integer(options.height) && options.height > 0) {
- this.options.claheHeight = options.height;
- } else {
- throw is.invalidParameterError('height', 'integer greater than zero', options.height);
- }
- if (is.defined(options.maxSlope)) {
- if (is.integer(options.maxSlope) && is.inRange(options.maxSlope, 0, 100)) {
- this.options.claheMaxSlope = options.maxSlope;
- } else {
- throw is.invalidParameterError('maxSlope', 'integer between 0 and 100', options.maxSlope);
- }
- }
- } else {
- throw is.invalidParameterError('options', 'plain object', options);
- }
- return this;
- }
- /**
- * Convolve the image with the specified kernel.
- *
- * @example
- * sharp(input)
- * .convolve({
- * width: 3,
- * height: 3,
- * kernel: [-1, 0, 1, -2, 0, 2, -1, 0, 1]
- * })
- * .raw()
- * .toBuffer(function(err, data, info) {
- * // data contains the raw pixel data representing the convolution
- * // of the input image with the horizontal Sobel operator
- * });
- *
- * @param {Object} kernel
- * @param {number} kernel.width - width of the kernel in pixels.
- * @param {number} kernel.height - height of the kernel in pixels.
- * @param {Array<number>} kernel.kernel - Array of length `width*height` containing the kernel values.
- * @param {number} [kernel.scale=sum] - the scale of the kernel in pixels.
- * @param {number} [kernel.offset=0] - the offset of the kernel in pixels.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function convolve (kernel) {
- if (!is.object(kernel) || !Array.isArray(kernel.kernel) ||
- !is.integer(kernel.width) || !is.integer(kernel.height) ||
- !is.inRange(kernel.width, 3, 1001) || !is.inRange(kernel.height, 3, 1001) ||
- kernel.height * kernel.width !== kernel.kernel.length
- ) {
- // must pass in a kernel
- throw new Error('Invalid convolution kernel');
- }
- // Default scale is sum of kernel values
- if (!is.integer(kernel.scale)) {
- kernel.scale = kernel.kernel.reduce(function (a, b) {
- return a + b;
- }, 0);
- }
- // Clip scale to a minimum value of 1
- if (kernel.scale < 1) {
- kernel.scale = 1;
- }
- if (!is.integer(kernel.offset)) {
- kernel.offset = 0;
- }
- this.options.convKernel = kernel;
- return this;
- }
- /**
- * Any pixel value greater than or equal to the threshold value will be set to 255, otherwise it will be set to 0.
- * @param {number} [threshold=128] - a value in the range 0-255 representing the level at which the threshold will be applied.
- * @param {Object} [options]
- * @param {Boolean} [options.greyscale=true] - convert to single channel greyscale.
- * @param {Boolean} [options.grayscale=true] - alternative spelling for greyscale.
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function threshold (threshold, options) {
- if (!is.defined(threshold)) {
- this.options.threshold = 128;
- } else if (is.bool(threshold)) {
- this.options.threshold = threshold ? 128 : 0;
- } else if (is.integer(threshold) && is.inRange(threshold, 0, 255)) {
- this.options.threshold = threshold;
- } else {
- throw is.invalidParameterError('threshold', 'integer between 0 and 255', threshold);
- }
- if (!is.object(options) || options.greyscale === true || options.grayscale === true) {
- this.options.thresholdGrayscale = true;
- } else {
- this.options.thresholdGrayscale = false;
- }
- return this;
- }
- /**
- * Perform a bitwise boolean operation with operand image.
- *
- * This operation creates an output image where each pixel is the result of
- * the selected bitwise boolean `operation` between the corresponding pixels of the input images.
- *
- * @param {Buffer|string} operand - Buffer containing image data or string containing the path to an image file.
- * @param {string} operator - one of `and`, `or` or `eor` to perform that bitwise operation, like the C logic operators `&`, `|` and `^` respectively.
- * @param {Object} [options]
- * @param {Object} [options.raw] - describes operand when using raw pixel data.
- * @param {number} [options.raw.width]
- * @param {number} [options.raw.height]
- * @param {number} [options.raw.channels]
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function boolean (operand, operator, options) {
- this.options.boolean = this._createInputDescriptor(operand, options);
- if (is.string(operator) && is.inArray(operator, ['and', 'or', 'eor'])) {
- this.options.booleanOp = operator;
- } else {
- throw is.invalidParameterError('operator', 'one of: and, or, eor', operator);
- }
- return this;
- }
- /**
- * Apply the linear formula `a` * input + `b` to the image to adjust image levels.
- *
- * When a single number is provided, it will be used for all image channels.
- * When an array of numbers is provided, the array length must match the number of channels.
- *
- * @example
- * await sharp(input)
- * .linear(0.5, 2)
- * .toBuffer();
- *
- * @example
- * await sharp(rgbInput)
- * .linear(
- * [0.25, 0.5, 0.75],
- * [150, 100, 50]
- * )
- * .toBuffer();
- *
- * @param {(number|number[])} [a=[]] multiplier
- * @param {(number|number[])} [b=[]] offset
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function linear (a, b) {
- if (!is.defined(a) && is.number(b)) {
- a = 1.0;
- } else if (is.number(a) && !is.defined(b)) {
- b = 0.0;
- }
- if (!is.defined(a)) {
- this.options.linearA = [];
- } else if (is.number(a)) {
- this.options.linearA = [a];
- } else if (Array.isArray(a) && a.length && a.every(is.number)) {
- this.options.linearA = a;
- } else {
- throw is.invalidParameterError('a', 'number or array of numbers', a);
- }
- if (!is.defined(b)) {
- this.options.linearB = [];
- } else if (is.number(b)) {
- this.options.linearB = [b];
- } else if (Array.isArray(b) && b.length && b.every(is.number)) {
- this.options.linearB = b;
- } else {
- throw is.invalidParameterError('b', 'number or array of numbers', b);
- }
- if (this.options.linearA.length !== this.options.linearB.length) {
- throw new Error('Expected a and b to be arrays of the same length');
- }
- return this;
- }
- /**
- * Recombine the image with the specified matrix.
- *
- * @since 0.21.1
- *
- * @example
- * sharp(input)
- * .recomb([
- * [0.3588, 0.7044, 0.1368],
- * [0.2990, 0.5870, 0.1140],
- * [0.2392, 0.4696, 0.0912],
- * ])
- * .raw()
- * .toBuffer(function(err, data, info) {
- * // data contains the raw pixel data after applying the matrix
- * // With this example input, a sepia filter has been applied
- * });
- *
- * @param {Array<Array<number>>} inputMatrix - 3x3 Recombination matrix
- * @returns {Sharp}
- * @throws {Error} Invalid parameters
- */
- function recomb (inputMatrix) {
- if (!Array.isArray(inputMatrix) || inputMatrix.length !== 3 ||
- inputMatrix[0].length !== 3 ||
- inputMatrix[1].length !== 3 ||
- inputMatrix[2].length !== 3
- ) {
- // must pass in a kernel
- throw new Error('Invalid recombination matrix');
- }
- this.options.recombMatrix = [
- inputMatrix[0][0], inputMatrix[0][1], inputMatrix[0][2],
- inputMatrix[1][0], inputMatrix[1][1], inputMatrix[1][2],
- inputMatrix[2][0], inputMatrix[2][1], inputMatrix[2][2]
- ].map(Number);
- return this;
- }
- /**
- * Transforms the image using brightness, saturation, hue rotation, and lightness.
- * Brightness and lightness both operate on luminance, with the difference being that
- * brightness is multiplicative whereas lightness is additive.
- *
- * @since 0.22.1
- *
- * @example
- * // increase brightness by a factor of 2
- * const output = await sharp(input)
- * .modulate({
- * brightness: 2
- * })
- * .toBuffer();
- *
- * @example
- * // hue-rotate by 180 degrees
- * const output = await sharp(input)
- * .modulate({
- * hue: 180
- * })
- * .toBuffer();
- *
- * @example
- * // increase lightness by +50
- * const output = await sharp(input)
- * .modulate({
- * lightness: 50
- * })
- * .toBuffer();
- *
- * @example
- * // decrease brightness and saturation while also hue-rotating by 90 degrees
- * const output = await sharp(input)
- * .modulate({
- * brightness: 0.5,
- * saturation: 0.5,
- * hue: 90,
- * })
- * .toBuffer();
- *
- * @param {Object} [options]
- * @param {number} [options.brightness] Brightness multiplier
- * @param {number} [options.saturation] Saturation multiplier
- * @param {number} [options.hue] Degrees for hue rotation
- * @param {number} [options.lightness] Lightness addend
- * @returns {Sharp}
- */
- function modulate (options) {
- if (!is.plainObject(options)) {
- throw is.invalidParameterError('options', 'plain object', options);
- }
- if ('brightness' in options) {
- if (is.number(options.brightness) && options.brightness >= 0) {
- this.options.brightness = options.brightness;
- } else {
- throw is.invalidParameterError('brightness', 'number above zero', options.brightness);
- }
- }
- if ('saturation' in options) {
- if (is.number(options.saturation) && options.saturation >= 0) {
- this.options.saturation = options.saturation;
- } else {
- throw is.invalidParameterError('saturation', 'number above zero', options.saturation);
- }
- }
- if ('hue' in options) {
- if (is.integer(options.hue)) {
- this.options.hue = options.hue % 360;
- } else {
- throw is.invalidParameterError('hue', 'number', options.hue);
- }
- }
- if ('lightness' in options) {
- if (is.number(options.lightness)) {
- this.options.lightness = options.lightness;
- } else {
- throw is.invalidParameterError('lightness', 'number', options.lightness);
- }
- }
- return this;
- }
- /**
- * Decorate the Sharp prototype with operation-related functions.
- * @private
- */
- module.exports = function (Sharp) {
- Object.assign(Sharp.prototype, {
- rotate,
- flip,
- flop,
- affine,
- sharpen,
- median,
- blur,
- flatten,
- unflatten,
- gamma,
- negate,
- normalise,
- normalize,
- clahe,
- convolve,
- threshold,
- boolean,
- linear,
- recomb,
- modulate
- });
- };
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