Imagemagick / Shell /子进程NodeJS

Posted

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Imagemagick / Shell /子进程NodeJS相关的知识,希望对你有一定的参考价值。

我似乎无法让Node了解我的Imagemagick转换命令。它在终端中运行良好,我已经尝试了大量不同的排列来转义字符,但它仍然会在我的args数组中读取每个单独的字符串值,以尝试转换图像:

convert input.jpg -write mpr:XY +delete -respect-parentheses ( mpr:XY -resize x640 -sampling-factor 4:2:0 -strip -interlace Plane +write output-640.jpg ) ( mpr:XY -resize x320 -sampling-factor 4:2:0 -strip -interlace Plane +write output-320.jpg ) ( mpr:XY -resize x155 -sampling-factor 4:2:0 -strip -interlace Plane +write output-155.jpg ) ( mpr:XY -resize x45 -sampling-factor 4:2:0 -strip -interlace Plane +write output-45.jpg ) null:

这在shell中运行正常。但是,这段代码完全失败了

// const spawn = require('child-process-promise').spawn;
var spawn = require('child_process').spawn;

function argsForSize(number) {
  return [
    '\(',
    'mpr:XY',
    '-resize',
    'x' + number, 
    '-sampling-factor', 
    '4:2:0', 
    '-strip', 
    '-interlace', 
    'Plane', 
    '+write', 
    'output-' + number +'.jpg', 
    '\)\'
  ]
}

let inputPath = '/Users/xconanm/Desktop/imagemagick/test-app/input.jpg';

var args = [
  inputPath, '\',
  '-write', 'mpr:XY', '\',       // resize width to 640
  '+delete', '\',      
  '-respect-parentheses', '\'
];
let extraArgs = argsForSize(640).concat(argsForSize(320)).concat(argsForSize(155)).concat(argsForSize(55));

extraArgs.push('null:');

args = args.concat(extraArgs)

let child = spawn('convert', args)
console.log(args);

child.stdout.on('data', function(data) {
  console.log('stdout: ' + data);
  //Here is where the output goes
});
child.stderr.on('data', function(data) {
  console.log('stderr: ' + data);
  //Here is where the error output goes
});
child.on('close', function(code) {
  console.log('closing code: ' + code);
  //Here you can get the exit code of the script
});
答案

得到它......可能效率低下但是:耸耸肩

// const spawn = require('child-process-promise').spawn;
var spawn = require('child_process').spawn;

function argsForSize(number) {
  return [
    '-write', 
    'mpr:XY', 
    '+delete',
    '-respect-parentheses',
    'mpr:XY',
    '-resize',
    'x' + number, 
    '-sampling-factor', 
    '4:2:0', 
    '-strip', 
    '-interlace', 
    'Plane', 
    '-write', 
    'output-' + number +'.jpg'
  ]
}

let inputPath = '/Users/xconanm/Desktop/imagemagick/test-app/input.jpg';

var args = [
  inputPath
];
let extraArgs = argsForSize(640).concat(argsForSize(320)).concat(argsForSize(155)).concat(argsForSize(55));

extraArgs.push('null:');

args = args.concat(extraArgs)

let child = spawn('convert', args)
console.log(args);

child.stdout.on('data', function(data) {
  console.log('stdout: ' + data);
  //Here is where the output goes
});
child.stderr.on('data', function(data) {
  console.log('stderr: ' + data);
  //Here is where the error output goes
});
child.on('close', function(code) {
  console.log('closing code: ' + code);
  //Here you can get the exit code of the script
  process.exit();
});

以上是关于Imagemagick / Shell /子进程NodeJS的主要内容,如果未能解决你的问题,请参考以下文章

从Python中的imagemagick子进程读取输出[重复]

shell向子进程发送信号

子shell

Go 子进程通信

子进程中的“shell”参数在 Windows 上是啥意思?

python子进程中的子shell