322 lines
9.4 KiB
JavaScript
322 lines
9.4 KiB
JavaScript
|
/**
|
||
|
|
* Module dependencies.
|
||
|
|
*/
|
||
|
|
|
||
|
|
var gm = require('gm')
|
||
|
|
, fs = require('fs')
|
||
|
|
, path = require('path')
|
||
|
|
, mkdirp = require('mkdirp')
|
||
|
|
, utils = require('./utils')
|
||
|
|
, imagesize = require('./size')
|
||
|
|
, imgr = require('./constants');
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A stub for skipping optimisation. Replace this function
|
||
|
|
* with your own to enable image optimisation.
|
||
|
|
*
|
||
|
|
* @param {String} path
|
||
|
|
* @param {Function} callback
|
||
|
|
*/
|
||
|
|
|
||
|
|
function noOptimisation(path, callback) {
|
||
|
|
callback();
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Default options.
|
||
|
|
*/
|
||
|
|
|
||
|
|
var default_options = {
|
||
|
|
orientation: imgr.CENTRE
|
||
|
|
, image_magick: false
|
||
|
|
, optimisation: noOptimisation
|
||
|
|
, gm_quality: 100
|
||
|
|
, crop_offset: 0
|
||
|
|
, filter: null
|
||
|
|
, interlace: null
|
||
|
|
, coalesce: true
|
||
|
|
, trace: function () {}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Create a new image converter.
|
||
|
|
*
|
||
|
|
* @param {String} image - the image to load
|
||
|
|
* @param {Object} options (optional)
|
||
|
|
*/
|
||
|
|
|
||
|
|
var Converter = exports.Converter = function (image, options) {
|
||
|
|
this.image = image;
|
||
|
|
this.options = utils.mergeDefaults(options, default_options);
|
||
|
|
this.gm = gm.subClass({ imageMagick: this.options.image_magick });
|
||
|
|
this.operation = {};
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Resize an image to the specified width.
|
||
|
|
*
|
||
|
|
* @param {Number} width
|
||
|
|
* @return this
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.resizeToWidth = function (width) {
|
||
|
|
this.operation.width = width;
|
||
|
|
return this;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Resize an image to the specified height.
|
||
|
|
*
|
||
|
|
* @param {Number} height
|
||
|
|
* @return this
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.resizeToHeight = function (height) {
|
||
|
|
this.operation.height = height;
|
||
|
|
return this;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Resize an image by the specified factor, e.g. 0.5 would resize the image
|
||
|
|
* to be half the width and height that it was.
|
||
|
|
*
|
||
|
|
* @param {Number} factor
|
||
|
|
* @return this
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.resizeByFactor = function (factor) {
|
||
|
|
this.operation.factor = factor;
|
||
|
|
return this;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Resize an image to an exact width and height using adaptive resizing.
|
||
|
|
* Crop the largest portion of the image with the same aspect ratio and
|
||
|
|
* then resize to the desired dimensions.
|
||
|
|
*
|
||
|
|
* @param {Number} width
|
||
|
|
* @param {Number} height
|
||
|
|
* @param {Number} orientation (optional)
|
||
|
|
* @return this
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.adaptiveResize = function (width, height, orientation) {
|
||
|
|
this.operation.width = width;
|
||
|
|
this.operation.height = height;
|
||
|
|
this.operation.orientation = orientation || this.options.orientation;
|
||
|
|
return this;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Crop an image to the specified width and height, starting from the
|
||
|
|
* specified x and y point.
|
||
|
|
*
|
||
|
|
* @param {Number} width
|
||
|
|
* @param {Number} height
|
||
|
|
* @param {Number} x (optional)
|
||
|
|
* @param {Number} y (optional)
|
||
|
|
* @return this
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.crop = function (width, height, x, y) {
|
||
|
|
this.operation.crop_width = width;
|
||
|
|
this.operation.crop_height = height;
|
||
|
|
this.operation.x = x || 0;
|
||
|
|
this.operation.y = y || 0;
|
||
|
|
return this;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get an image size.
|
||
|
|
*
|
||
|
|
* @param {String} image
|
||
|
|
* @param {Function} callback
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.size = function (image, callback) {
|
||
|
|
imagesize(image, callback);
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Execute the pending conversion and save the resulting image to `output`.
|
||
|
|
*
|
||
|
|
* @param {String} output
|
||
|
|
* @param {Function} callback
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.save = function (output, callback) {
|
||
|
|
var dir = path.dirname(output)
|
||
|
|
, image = this.gm(this.image)
|
||
|
|
, operation = this.operation
|
||
|
|
, self = this;
|
||
|
|
|
||
|
|
this.callback = callback;
|
||
|
|
|
||
|
|
//Create the output dir if it doesn't already exist
|
||
|
|
mkdirp(dir, function () {
|
||
|
|
|
||
|
|
//Skip resize/crop?
|
||
|
|
if (!operation.width && !operation.height && !operation.factor && !operation.crop_width) {
|
||
|
|
return self.copy(self.image, output, function (err) {
|
||
|
|
return self.finalise(err);
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
//Get the current image dimensions
|
||
|
|
self.size(self.image, function (err, size) {
|
||
|
|
if (err || !size) {
|
||
|
|
return self.finalise(err || 'Failed to obtain image dimensions');
|
||
|
|
}
|
||
|
|
|
||
|
|
//Adaptive resizing
|
||
|
|
if (operation.width && operation.height && typeof operation.crop_width === 'undefined') {
|
||
|
|
var original_ar = size.width / size.height
|
||
|
|
, new_ar = operation.width / operation.height
|
||
|
|
, crop_offset = 0;
|
||
|
|
if (new_ar < original_ar) {
|
||
|
|
operation.crop_width = Math.round(operation.width * size.height / operation.height);
|
||
|
|
if (self.options.crop_offset) {
|
||
|
|
crop_offset = size.width * self.options.crop_offset / 100;
|
||
|
|
}
|
||
|
|
if (operation.orientation === imgr.LEFT) {
|
||
|
|
operation.x = crop_offset;
|
||
|
|
if (operation.x + operation.crop_width > size.width) {
|
||
|
|
operation.x = size.width - operation.crop_width;
|
||
|
|
}
|
||
|
|
} else if (operation.orientation === imgr.CENTRE) {
|
||
|
|
operation.x = Math.round((size.width - operation.crop_width) / 2);
|
||
|
|
} else if (operation.orientation === imgr.RIGHT) {
|
||
|
|
operation.x = Math.max(size.width - operation.crop_width - crop_offset, 0);
|
||
|
|
}
|
||
|
|
} else if (new_ar > original_ar) {
|
||
|
|
operation.crop_height = Math.round(operation.height * size.width / operation.width);
|
||
|
|
if (self.options.crop_offset) {
|
||
|
|
crop_offset = size.height * self.options.crop_offset / 100;
|
||
|
|
}
|
||
|
|
if (operation.orientation === imgr.TOP) {
|
||
|
|
operation.y = crop_offset;
|
||
|
|
if (operation.y + operation.crop_height > size.height) {
|
||
|
|
operation.y = size.height - operation.crop_height;
|
||
|
|
}
|
||
|
|
} else if (operation.orientation === imgr.CENTRE) {
|
||
|
|
operation.y = Math.round((size.height - operation.crop_height) / 2);
|
||
|
|
} else if (operation.orientation === imgr.BOTTOM) {
|
||
|
|
operation.y = Math.max(size.height - operation.crop_height - crop_offset, 0);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//Coalesce images (when resizing animated gifs)
|
||
|
|
if (self.options.coalesce) {
|
||
|
|
image.coalesce();
|
||
|
|
}
|
||
|
|
|
||
|
|
//Apply the crop operation
|
||
|
|
if (operation.crop_width || operation.crop_height) {
|
||
|
|
operation.x = operation.x || 0;
|
||
|
|
operation.y = operation.y || 0;
|
||
|
|
operation.crop_width = operation.crop_width || (size.width - operation.x);
|
||
|
|
operation.crop_height = operation.crop_height || (size.height - operation.y);
|
||
|
|
image.crop(operation.crop_width, operation.crop_height, operation.x, operation.y);
|
||
|
|
image.repage(0, 0, 0, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
//Resize by a constant factor
|
||
|
|
if (operation.factor) {
|
||
|
|
operation.width = Math.round(size.width * operation.factor);
|
||
|
|
operation.height = Math.round(size.height * operation.factor);
|
||
|
|
}
|
||
|
|
|
||
|
|
image.quality(self.options.gm_quality);
|
||
|
|
|
||
|
|
//Use a custom resizing filter
|
||
|
|
if (self.options.filter) {
|
||
|
|
image.filter(self.options.filter);
|
||
|
|
}
|
||
|
|
|
||
|
|
//Specify the type of interlacing scheme
|
||
|
|
if (self.options.interlace) {
|
||
|
|
image.interlace(self.options.interlace);
|
||
|
|
}
|
||
|
|
|
||
|
|
//Fill in the missing dimension
|
||
|
|
if (!operation.width && operation.height) {
|
||
|
|
operation.width = Math.ceil(operation.height / size.height * size.width);
|
||
|
|
}
|
||
|
|
if (!operation.height && operation.width) {
|
||
|
|
operation.height = Math.ceil(operation.width / size.width * size.height);
|
||
|
|
}
|
||
|
|
|
||
|
|
//Apply the resize operation
|
||
|
|
if (operation.width || operation.height) {
|
||
|
|
image.resize(operation.width, operation.height);
|
||
|
|
}
|
||
|
|
|
||
|
|
//Save the image
|
||
|
|
image.write(output, function (err) {
|
||
|
|
self.options.trace('gm_convert');
|
||
|
|
self.image = output;
|
||
|
|
self.finalise(err, operation);
|
||
|
|
});
|
||
|
|
});
|
||
|
|
});
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Copy a file.
|
||
|
|
*
|
||
|
|
* @param {String} src
|
||
|
|
* @param {String} dest
|
||
|
|
* @param {Function} callback
|
||
|
|
* @api private
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.copy = function (src, dest, callback) {
|
||
|
|
var stream = fs.createReadStream(src);
|
||
|
|
this.options.trace('image_copy');
|
||
|
|
stream.pipe(fs.createWriteStream(dest));
|
||
|
|
stream.on('end', callback);
|
||
|
|
stream.on('error', callback);
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Finalise the save() process.
|
||
|
|
*
|
||
|
|
* @param {Function} callback
|
||
|
|
* @api private
|
||
|
|
*/
|
||
|
|
|
||
|
|
Converter.prototype.finalise = function (err, operation) {
|
||
|
|
var callback = this.callback
|
||
|
|
, image = this.image
|
||
|
|
, optimise = this.options.optimisation;
|
||
|
|
|
||
|
|
//Reset the operation
|
||
|
|
this.operation = {};
|
||
|
|
delete this.image;
|
||
|
|
delete this.callback;
|
||
|
|
|
||
|
|
if (err || !optimise) {
|
||
|
|
if (typeof err === 'object' && err.message.indexOf('installed graphicsmagick') >= 0) {
|
||
|
|
err = 'Graphicsmagick is not installed';
|
||
|
|
}
|
||
|
|
return callback(err);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (optimise.length === 2) {
|
||
|
|
optimise(image, callback);
|
||
|
|
} else if (optimise.length === 3) {
|
||
|
|
optimise(image, operation, callback);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Manage concurrency.
|
||
|
|
*/
|
||
|
|
|
||
|
|
utils.concurrent(Converter.prototype, 'size', 5);
|
||
|
|
utils.floodProtection(Converter.prototype, 'size');
|
||
|
|
utils.concurrent(Converter.prototype, 'save', 5);
|
||
|
|
utils.floodProtection(Converter.prototype, 'save');
|
||
|
|
|