Github url

Luban

by Curzibn

Curzibn /Luban

Luban(鲁班)—Image compression with efficiency very close to WeChat Moments/可能是最接近微信朋友圈的图片压缩算法

11.8K Stars 2.0K Forks Last release: almost 2 years ago (turbo-1.0.0) Apache License 2.0 187 Commits 9 Releases

Available items

No Items, yet!

The developer of this repository has not created any items for sale yet. Need a bug fixed? Help with integration? A different license? Create a request here:

Luban

Build StatusDownload

:book: English Documentation

Luban

(鲁班) ——

Android

图片压缩工具,仿微信朋友圈压缩策略。

Luban-turbo

—— 鲁班项目的

turbo

版本,[查看

trubo

分支](https://github.com/Curzibn/Luban/tree/turbo)。

写在前面

家境贫寒,工作繁忙。只能不定期更新,还望网友们见谅!

项目描述

目前做

App

开发总绕不开图片这个元素。但是随着手机拍照分辨率的提升,图片的压缩成为一个很重要的问题。单纯对图片进行裁切,压缩已经有很多文章介绍。但是裁切成多少,压缩成多少却很难控制好,裁切过头图片太小,质量压缩过头则显示效果太差。

于是自然想到

App

巨头“微信”会是怎么处理,

Luban

(鲁班)就是通过在微信朋友圈发送近100张不同分辨率图片,对比原图与微信压缩后的图片逆向推算出来的压缩算法。

因为有其他语言也想要实现

Luban

,所以描述了一遍算法步骤

因为是逆向推算,效果还没法跟微信一模一样,但是已经很接近微信朋友圈压缩后的效果,具体看以下对比!

效果与对比

内容 | 原图 |

Luban

|

Wechat

---- | ---- | ------ | ------ 截屏 720P |720_1280,390k|720_1280,87k|720_1280,56k 截屏 1080P|1080_1920,2.21M|1080_1920,104k|1080_1920,112k 拍照 13M(4:3)|3096_4128,3.12M|1548_2064,141k|1548_2064,147k 拍照 9.6M(16:9)|4128_2322,4.64M|1032_581,97k|1032_581,74k 滚动截屏|1080_6433,1.56M|1080_6433,351k|1080*6433,482k

导入

implementation 'top.zibin:Luban:1.1.8'

使用

方法列表

方法 | 描述 ---- | ---- load | 传入原图 filter | 设置开启压缩条件 ignoreBy | 不压缩的阈值,单位为K setFocusAlpha | 设置是否保留透明通道 setTargetDir | 缓存压缩图片路径 setCompressListener | 压缩回调接口 setRenameListener | 压缩前重命名接口

异步调用

Luban

内部采用

IO

线程进行图片压缩,外部调用只需设置好结果监听即可:

Luban.with(this) .load(photos) .ignoreBy(100) .setTargetDir(getPath()) .filter(new CompressionPredicate() { @Override public boolean apply(String path) { return !(TextUtils.isEmpty(path) || path.toLowerCase().endsWith(".gif")); } }) .setCompressListener(new OnCompressListener() { @Override public void onStart() { // TODO 压缩开始前调用,可以在方法内启动 loading UI } @Override public void onSuccess(File file) { // TODO 压缩成功后调用,返回压缩后的图片文件 } @Override public void onError(Throwable e) { // TODO 当压缩过程出现问题时调用 } }).launch();

同步调用

同步方法请尽量避免在主线程调用以免阻塞主线程,下面以rxJava调用为例

Flowable.just(photos) .observeOn(Schedulers.io()) .map(new Function<list>, List<file>&gt;() {
      @Override public List<file> apply(@NonNull List<string> list) throws Exception {
        // 同步方法直接返回压缩后的文件
        return Luban.with(MainActivity.this).load(list).get();
      }
    })
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe();
</string></file></file></list>

RELEASE NOTE

Here

License

Copyright 2016 Zheng Zibin Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.