base64

Base64 video encoding - good\bad idea?

我是研究僧i 提交于 2020-01-11 15:50:07
问题 I'm working on a mobile front-end project using cordova, and the backend developer i'm working with insists that the media files (images/videos) should be transferred as base64 encoded in json files. Now, with images it's so far working. Although it freezes the UI for a few seconds, it can be deferred somehow. The videos however are so far a pain to handle, the length of a single/simple video being transferred is nearly 300,000 in length. It brings my poor laptop through a wild spin, and gets

vue中使用base64和md5

余生颓废 提交于 2020-01-11 10:31:49
原文链接: 点我 1.在项目根目录下安装 cnpm install --save js-base64 cnpm install --save js-md5 2.在项目文件中引入 import md5 from 'js-md5'; let Base64 = require('js-base64').Base64; 3.在项目文件中使用 base64: Base64.encode('dankogai'); // ZGFua29nYWk= Base64.decode('ZGFua29nYWk='); // dankogai md5: md5(''); // d41d8cd98f00b204e9800998ecf8427e eg: 1 <script type="text/ecmascript-6"> 2 3 let Base64 = require('js-base64').Base64; //Base64.encode('小飼弾');Base64.decode('ZGFua29nYWk='); 4 5 export default { 6 data () { 7 8 return {}, 9 10 }, 11 12 methods: { 13 14 openFun: function(){ 15 16 let urlStr = "token=11526538-0059-4199

Decode base64 filestream with FromBase64Transform

a 夏天 提交于 2020-01-11 06:50:11
问题 The example from MSDN seems to read the whole file into memory. I don't want that. The file should be processed block by block. Therefore I tried to rewrite the example: using (FromBase64Transform myTransform = new FromBase64Transform (FromBase64TransformMode.IgnoreWhiteSpaces)) { byte[] transformBuffer = new byte[myTransform.OutputBlockSize]; using (FileStream inputFile = File.OpenRead("/path/to/file/47311.b64")) { using(FileStream outputFile = File.OpenWrite("/path/to/file/47311.jpg")){ int

Using PhoneGap, How to get base64 image data of the photo chosen from photo library in iPhone

房东的猫 提交于 2020-01-11 05:06:20
问题 Using PhoneGap(Cordova), Am trying to get base64 image data of the photo chosen from the photo library. I could do that.. when the photo is captured from camera, With the below snippet of code in Cordova. navigator.camera.getPicture(onSuccess, onFail, { quality: 50, destinationType: Camera.DestinationType.DATA_URL }); function onSuccess(imageData) { var image = document.getElementById('myImage'); image.src = "data:image/jpeg;base64," + imageData; } function onFail(message) { alert('Failed

H5 中html 页面存为图片并长按 保存

℡╲_俬逩灬. 提交于 2020-01-11 04:48:56
最近接到的一个新需求:页面一个静态H5,中间有一页是输入信息,然后跳转到最后一页,自动将页面生成图片,用户可以长按图片保存到手机上。 展示一下最后一页的样子: 刚拿到这个需求,在网上看了很多文章,最普遍的是使用 html2canvas + canvas2image 来实现。于是,跟着前人的脚步,踏上了一个不断采坑采坑采坑的旅程。 下面直接描述我在做这个需求过程中遇到的问题以及解决办法吧: 1.html2canvas 图片跨域: 这个问题网上很多解决办法: 这个是最常用的, 刚开始我只是加了红色框里面的这一句,但是并没有任何作用,依旧报错。后来看到有人说,加上前面那一句,所以果断在加进去。 这两句其实表达的是同一个意思:允许图片跨域。 当然,也有网友说,直接给一个空值就可以,我当时试了一下,并不ok~~~~. 2.多次使用canvas drawImage 方法图片展示问题 2.1 图片加载顺序问题 在我这个需求里面,肯定是文字描述以及二维码是展示在图片上面的,刚开始我是 1. drawImage 文字, 2. drawImage 二维码 3. drawImage 背景大图 然而,结果让我大吃一惊,只有背景图加载渲染出来了。然后,通过无所不能的网络才知道:drawImage 的顺序应该是: 图片最底下的需要最先加载渲染。 2.2 图片显示不完整 在2.1 问题出现的同时还遇到了这个问题

Calculate actual data size from Base64 encoded string length

怎甘沉沦 提交于 2020-01-11 04:34:09
问题 Given data encoded as a Base64-encoded string, can I somehow calculate the actual length of the raw data that has been encoded only by looking at the length of the Base64-encoded string? I don't want to traverse the string if not necessary (this also includes string operations on the trailling characters of the encoded string to check for padding). 回答1: The exact length cannot be calculated unless you look at the padding. Without looking for padding, the best you can do is calculate an upper

C#和Python 图片和base64的互转

China☆狼群 提交于 2020-01-11 03:06:15
C#实例代码: /// <summary> /// 图片转base64 /// </summary> /// <param name="bmp"></param> /// <returns></returns> private string ImgToByte(Bitmap bmp) { string result; try { //Image bmp = new Bitmap(filename); MemoryStream memoryStream = new MemoryStream(); bmp.Save(memoryStream, ImageFormat.Jpeg); byte[] array = new byte[memoryStream.Length]; memoryStream.Position = 0L; memoryStream.Read(array, 0, (int)memoryStream.Length); memoryStream.Close(); result = Convert.ToBase64String(array); } catch (Exception ex) { result = null; } return result; } /// <summary> /// base64转图片 /// </summary> /// <param name

OSS(阿里)上的图片添加水印

流过昼夜 提交于 2020-01-11 02:02:18
1.将UI给你的水印图上传至OSS服务器上; 2.拿到图片路径,将上传后图片的后缀加上"?x-oss-process=image/resize,P_60"转为base64格式;base64加密链接 --------P是水印的大小 3.在需要加水印的图片路径后面加上"?x-oss-process=image/resize,w_400/watermark,image_水印的base64编码,t_50,g_se,x_20,y_50".---------后面是一些参数; 4.视频戳针 找到视频7s处的内容,输出为jpg。 http://a-image-demo.oss-cn-qingdao.aliyuncs.com/demo.mp4?x-oss-process=video/snapshot,t_7000,f_jpg,w_800,h_600,m_fast 5.图片缩放 单边缩略 按宽高:将图缩略成高度为 100,宽度按比例处理。 http://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/resize,h_100 按长边短边:将图最长边限制在 100 像素,短边按比例处理。 http://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x

vue中使用 MD5与base64

六眼飞鱼酱① 提交于 2020-01-11 00:21:50
  在刚刚完成的项目中,用户登录与微信扫码注册的时候,分别用到了MD5加密与base64解密。 一 . md5使用   本地安装 : cnpm install --save js-md5   min.js 中引入 : import md5 from 'js-md5'   使用方法 : console.log(md5('12345678'));     // '25d55ad283aa400af464c76d713c07ad' 二. base64使用   项目中引用 base64.js 文件: import base64 from '../../api/base64';   使用方法:window.bases64.decode(localStorage.weixin) 来源: https://www.cnblogs.com/syh119/p/9039624.html

非对称加密解密

不问归期 提交于 2020-01-11 00:04:32
一. 加密代码 #私钥加密 公钥解密import rsa import base64 # #生成公钥私钥 pub_key_obj, priv_key_obj = rsa.newkeys(1024) pub_key_str = pub_key_obj.save_pkcs1() pub_key_code = base64.standard_b64encode(pub_key_str) priv_key_str = priv_key_obj.save_pkcs1() priv_key_code = base64.standard_b64encode(priv_key_str) print(pub_key_code) print(priv_key_code) #加密 def encrypt(values): key_str = base64.standard_b64decode(pub_key_code) pk = rsa.PublicKey.load_pkcs1(key_str) val = rsa.encrypt(values.encode('utf-8'),pk) return val ret = encrypt('hhhhhh') print(ret) def decrypt(values): key_str = base64.standard_b64decode(priv_key