Nodejs fixes png images processed by ipa,

Nodejs fixes png images processed by ipa,

Recently, a project encountered a requirement: parse the apk and ipa packages and upload the icons to the server.

Problem

The parsing and uploading process is relatively simple. I use JSZip to decompress apk and ipa, and then upload the icon in it to the server. However, when I use images on a webpage, the problem occurs. There is no problem with the icon in the apk, but the parsed image in ipa can be displayed normally in safari and cannot be displayed in any other browser.

Cause

Google found that Apple optimized the png image. For more information, see this article. In this article, we can find some useful information:

Apple uses PNGCursh open source library to crush png images inside iPA files。

Solution

As a front-end engineer, I want to use javascript to solve this problem. In fact, some people have already solved this problem in foreign countries. NodeJS-PNGDefry is fine. Unfortunately, it has not been maintained for too long and cannot run.

I can't find any available ones. I can only write one by myself. Therefore, node-pngdefry is available. Node-pngdefry has a clear function, that is, it uses Javascript to restore png images processed by Apple.

Node-pngdefry:

Command Line usage

Install:

$ npm install -g pngdefry

Then run:

$ pngdefry -i icon.png -o icon.new.png

Use in Node. js

$ npm install pngdefry --save-dev

var pngdefry = require('pngdefry');var path = require('path');var input = path.join(__dirname, 'icon.png');var output = path.join(__dirname, 'icon.new.png');pngdefry(input, output, function(err) { if (err) {  return; } console.log('success');});

Test

$ npm test

Project address

Node-pngdefry

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