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@19h

19h/resize.js

Last active Dec 4, 2017
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Streamed image resize using lwip (@wtr7)
// modules
var lwip = require('lwip'),
path = require('path'),
fs = require('fs'),
rstream = require('stream').Readable;
// config
var placesPath = '/Users/apx/Downloads/places';
// helper
var isHiddenPath = function (fn) {
return /(^|.\/)\.+[^\/\.]/g.test(fn);
};
var resizePhotos = function () {
var stream = new rstream,
files = [];
// actual resize procedure
var _resize = function () {
var i = 0, n = files.length;
var _next = function () {
++i === n && stream.emit('end');
}
files.forEach(function (fn) {
process.nextTick(function () {
var image_base = fn[0];
fs.readFile(image_base, function (err, buf) {
// bubble up error if one is existent
if (err) return stream.emit('error', 'Couldn\'t open image for resize: ' + image_base, err), _next();
// instanciate lwip per image
lwip.open(buf, fn[0].split('.').pop() === 'png' ? 'png' : 'jpg', function(err, image) {
// bubble up error if one is existent
if (err) return stream.emit('error', '[lwip] Unspecific error: ' + image_base, err), _next();
image
// make this call chainable,
// so that it looks nicely
.batch()
// resize 400x400 where local center is global center
.crop(400, 400)
// export as buffer
.toBuffer('jpg', function(err, buffer) {
// bubble up error if one is existent
if (err) return stream.emit('error', 'Couldn\'t export buffer: ' + image_base, err), _next();
// remove extension, add jpg
var out_path = fn[1].split(".").slice(0, -1) + '.jpg';
// queue write
fs.writeFile(out_path, buffer, function (err) {
// emit resize event
stream.emit('resize', fn[0], out_path);
_next();
})
})
});
});
})
})
};
// aggregate files
process.nextTick(function () {
fs.readdir(placesPath, function(err, folders) {
// remove all hidden paths
folders = folders.filter(function (fn) {
return !isHiddenPath(fn);
});
var i = 0, n = folders.length;
var _next = function () {
++i === n && _resize();
}
// iterate over folders
folders.forEach(function(folder) {
folder = path.join(placesPath, folder);
fs.readdir(folder, function(err, images) {
// bubble up error if one is existent
if (err) return stream.emit('error', 'Couldn\'t read folder: ' + folder), _next();
// remove all hidden files
images = images
.filter(function (fn) {
// ignore hidden files and thumb_* files
return !isHiddenPath(fn) && fn.indexOf('thumb_');
})
.map(function (fn) {
return [
folder + '/' + fn,
folder + '/thumb_' + fn
]
});
// append results to files array
files.push.apply(files, images);
_next();
});
});
});
});
return stream;
}
/*
exports.setThumbs = function(req, res) {
resizePhotos()
// errors
.on('error', function (msg) {
})
// resizes
.on('resize', function (fn) {
res.write('Resized "' + fn + "\n");
})
.on('end', function () {
res.end("Ok, resized all of them!");
});
}
*/
resizePhotos()
// errors
.on('error', function (msg, err) {
console.log(msg, err);
})
// resizes
.on('resize', function (fn, thumb) {
console.log('Resized "' + fn + '" -> "' + thumb + '"');
})
.on('end', function () {
console.log("Ok, resized all of them!");
});
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