Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

using -format for identify to get more robust results #35

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
Open

using -format for identify to get more robust results #35

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
189c545
using identify -format to get more robust results
naltatis Mar 9, 2012
648dae3
fixed exec to make it work with node > 0.8
naltatis Sep 11, 2012
fda27fe
make it work with node > 1.0.0, on version 4.2.0 it eventually sent e…
proll Nov 7, 2015
1e39bb1
Merge pull request #1 from proll/master
naltatis Nov 16, 2015
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
175 changes: 43 additions & 132 deletions imagemagick.js
View file
Open in desktop
@@ -1,139 +1,48 @@
var childproc = require('child_process'),
EventEmitter = require('events').EventEmitter;


function exec2(file, args /*, options, callback */) {
var options = { encoding: 'utf8'
, timeout: 0
, maxBuffer: 500*1024
, killSignal: 'SIGKILL'
, output: null
};

var callback = arguments[arguments.length-1];
if ('function' != typeof callback) callback = null;

if (typeof arguments[2] == 'object') {
var keys = Object.keys(options);
for (var i = 0; i < keys.length; i++) {
var k = keys[i];
if (arguments[2][k] !== undefined) options[k] = arguments[2][k];
}
}

var child = childproc.spawn(file, args);
var killed = false;
var timedOut = false;

var Wrapper = function(proc) {
this.proc = proc;
this.stderr = new Accumulator();
proc.emitter = new EventEmitter();
proc.on = proc.emitter.on.bind(proc.emitter);
this.out = proc.emitter.emit.bind(proc.emitter, 'data');
this.err = this.stderr.out.bind(this.stderr);
this.errCurrent = this.stderr.current.bind(this.stderr);
};
Wrapper.prototype.finish = function(err) {
this.proc.emitter.emit('end', err, this.errCurrent());
};

var Accumulator = function(cb) {
this.stdout = {contents: ""};
this.stderr = {contents: ""};
this.callback = cb;

var limitedWrite = function(stream) {
return function(chunk) {
stream.contents += chunk;
if (!killed && stream.contents.length > options.maxBuffer) {
child.kill(options.killSignal);
killed = true;
}
};
};
this.out = limitedWrite(this.stdout);
this.err = limitedWrite(this.stderr);
};
Accumulator.prototype.current = function() { return this.stdout.contents; };
Accumulator.prototype.errCurrent = function() { return this.stderr.contents; };
Accumulator.prototype.finish = function(err) { this.callback(err, this.stdout.contents, this.stderr.contents); };

var std = callback ? new Accumulator(callback) : new Wrapper(child);

var timeoutId;
if (options.timeout > 0) {
timeoutId = setTimeout(function () {
if (!killed) {
child.kill(options.killSignal);
timedOut = true;
killed = true;
timeoutId = null;
}
}, options.timeout);
var spawn = require('child_process').spawn,
EventEmitter = require('events').EventEmitter,
StringDecoder = require('string_decoder').StringDecoder;

// based on https://github.com/bahamas10/node-exec
function exec2(program, args, opts, callback) {
var out = '',
err = '',
code,
i = 0,
decoder = new StringDecoder(),
v = process.version.split('.'),
version_major = v[0],
version_minor = v[1];

if (typeof opts === 'function') {
callback = opts;
opts = null;
}
var child = spawn(program, args, opts);

child.stdout.setEncoding(options.encoding);
child.stderr.setEncoding(options.encoding);
child.stdout.on('data', function(data) {
out += decoder.write(data);
});
child.stderr.on('data', function(data) {
err += decoder.write(data);
});

child.stdout.addListener("data", function (chunk) { std.out(chunk, options.encoding); });
child.stderr.addListener("data", function (chunk) { std.err(chunk, options.encoding); });
child.on('exit', function(c) {
code = c;
if (++i >= 2 || (version_major === 0 && version_minor < 8)) callback(err, out, code);
});

child.addListener("exit", function (code, signal) {
if (timeoutId) clearTimeout(timeoutId);
if (code === 0 && signal === null) {
std.finish(null);
} else {
var e = new Error("Command "+(timedOut ? "timed out" : "failed")+": " + std.errCurrent());
e.timedOut = timedOut;
e.killed = killed;
e.code = code;
e.signal = signal;
std.finish(e);
}
child.on('close', function() {
if (++i >= 2) callback(err, out, code);
});

return child;
};


function parseIdentify(input) {
var lines = input.split("\n"),
prop = {},
props = [prop],
prevIndent = 0,
indents = [indent],
currentLine, comps, indent;

lines.shift(); //drop first line (Image: name.jpg)

for (i in lines) {
currentLine = lines[i];
if (currentLine.length > 0) {
indent = currentLine.search(/\S/);
comps = currentLine.split(': ');
if (indent > prevIndent) indents.push(indent);
while (indent < prevIndent) {
indents.pop();
prop = props.pop();
prevIndent = indents[indents.length - 1];
}
if (comps.length < 2) {
props.push(prop);
prop = prop[currentLine.split(':')[0].trim().toLowerCase()] = {};
} else {
prop[comps[0].trim().toLowerCase()] = comps[1].trim()
}
prevIndent = indent;
}
}
return props[0];
};

// see http://www.imagemagick.org/script/escape.php for formatting options
exports.identify = function(pathOrArgs, callback) {
var isCustom = Array.isArray(pathOrArgs),
isData,
args = isCustom ? ([]).concat(pathOrArgs) : ['-verbose', pathOrArgs];
args = isCustom ? ([]).concat(pathOrArgs) : ['-format', '%m %w %h %z %Q', pathOrArgs];

if (typeof args[args.length-1] === 'object') {
isData = true;
Expand All @@ -151,14 +60,16 @@ exports.identify = function(pathOrArgs, callback) {
if (isCustom) {
result = stdout;
} else {
result = parseIdentify(stdout);
geometry = result['geometry'].split(/x/);

result.format = result.format.match(/\S*/)[0]
result.width = parseInt(geometry[0]);
result.height = parseInt(geometry[1]);
result.depth = parseInt(result.depth);
if (result.quality !== undefined) result.quality = parseInt(result.quality) / 100;
var v = stdout.trim().split(' ');
result = {
format: v[0],
width: parseInt(v[1]),
height: parseInt(v[2]),
depth: parseInt(v[3])
};
if (v[4] !== "0") {
result.quality = parseInt(v[4]) / 100;
}
}
}
callback(err, result);
Expand Down