上传时图像方向错误 - Amazon S3

Question

我让用户使用Multer-S3 将多个图像直接上传到Amazon-S3,然后通过循环在前端显示这些图像.一切都很完美.

但是,当通过手机上传图像(在iPhone或Android上拍摄的图像)时,方向在移动设备上是正确的,但在桌面上没有正确的方向.主要问题.

这是由于我相信EXIF数据的图像.

看起来像ImageMagick或Kraken JS https://kraken.io/docs/storage-s3可能是一种解决方法,但对于我的生活,我无法弄清楚如何实现我上传和显示图像的方式如下所示.

我如何更改下面的代码以自动定位图像？注意:它必须适用于多个图像.

谢谢你的帮助!

Heres是我让用户一次将多个图像直接上传到Amazon-S3的方式:

aws.config.update({
    secretAccessKey: 'AccessKey',
    accessKeyId: 'KeyID',
    region: 'us-east-2'
});

var s3 = new aws.S3();

    var storage =  multerS3({
        limits : { files: 25 },
        s3: s3,
        bucket: 'files',
        key: function (req, file, cb) {
            var fileExtension = file.originalname.split(".")[1];
            var path = "uploads/" + req.user._id + Date.now() + "." + fileExtension;
            cb(null, path); 
        },
    })


var upload = multer({storage: storage}).any("images", 25);

router.post("/", middleware.isLoggedIn, function(req, res, next){

        upload(req,res,function(err) {
        if(err) {
        console.log(err);
        res.redirect('/')
        }




Listings.findById(req.params.id, function(err, foundListings){

    var allimages = []

            if(typeof req.files !== "undefined") {
            for(var i = 0; i < req.files.length; i++) {
                allimages.push(req.files[i].key);
            }
            }
 var currentimages = allimages;

 var newListings = {currentimages:currentimages}
 //Removed the other Model aspects
    Listings.create(newListings, function(err, newlyCreated){
        if(err){
            console.log(err);
        } else {

 res.redirect("/listings");
    }
    });
    });

我如何在前端显示图像.Listings.currentimages是一个包含所有图像链接的数组.

app.locals.awspath = "https://s3.us-east-2.amazonaws.com/myfiles/";

// awspath 是我的Amazon-S3路径的文件路径

<div id='allimages'>
<% for(var i = 0; i < listings.currentimages.length; i++ ) { %>
<div class='smallerImages'>

<%  var url2 = awspath + listings.currentimages[i] %>
<img class="small" src="<%= url2 %>">

</div>
<% } %>
</div>

Answer 1

问题是iOS设置了图像的EXIF元数据,导致了这种行为.您可以使用可以读取EXIF元数据的库并为您旋转图像.

jpeg-autorotate(https://github.com/johansatge/jpeg-autorotate)是一个非常简单的库,有非常好的文档(你应该看一下).

例

var jo = require('jpeg-autorotate');
var fs = require('fs');

// var options = {quality: 85};
var options = {};
var path = '/tmp/Portrait_8.jpg'; // You can use a Buffer, too
jo.rotate(path, options, function(error, buffer, orientation) {
    if (error) {
        console.log('An error occurred when rotating the file: ' + error.message);
        return;
    }
    console.log('Orientation was: ' + orientation);

    // upload the buffer to s3, save to disk or more ...
    fs.writeFile("/tmp/output.jpg", buffer, function(err) {
        if(err) {
            return console.log(err);
        }

        console.log("The file was saved!");
    });
});

您可以从此处找到具有不同EXIF旋转元数据的一些示例图像

转换为AWS Lambda函数

// Name this file index.js and zip it + the node_modules then upload to AWS Lambda

console.log('Loading function');
var aws = require('aws-sdk');
var s3 = new aws.S3({apiVersion: '2006-03-01'});
var jo = require('jpeg-autorotate');

// Rotate an image given a buffer
var autorotateImage = function(data, callback) {
  jo.rotate(data, {}, function(error, buffer, orientation) {
      if (error) {
          console.log('An error occurred when rotating the file: ' + error.message);
          callback(error, null);
      } else {
        console.log('Orientation was: ' + orientation);
        callback(null, buffer);
      }
  });
};

// AWS Lambda runs this on every new file upload to s3
exports.handler = function(event, context, callback) {
    console.log('Received event:', JSON.stringify(event, null, 2));
    // Get the object from the event and show its content type
    var bucket = event.Records[0].s3.bucket.name;
    var key = event.Records[0].s3.object.key;
    s3.getObject({Bucket: bucket, Key: key}, function(err, data) {
        if (err) {
            console.log("Error getting object " + key + " from bucket " + bucket +
                ". Make sure they exist and your bucket is in the same region as this function.");
            callback("Error getting file: " + err, null);
        } else {
            // log the content type, should be an image
            console.log('CONTENT TYPE:', data.ContentType);
            // rotate the image
            autorotateImage(data.Body, function(error, image) {
              if (error) {
                callback("Error rotating image: " + error, null);
              }

              const params = {
                Bucket: bucket,
                  Key: 'rotated/' + key,
                  Body: image
              };
              // Upload new image, careful not to upload it in a path that will trigger the function again!
              s3.putObject(params, function (err, data) {
                if (error) {
                    callback("Error uploading rotated image: " + error, null);
                } else {
                  console.log("Successfully uploaded image on S3", data);
                  // call AWS Lambda's callback, function was successful!!!
                  callback(null, data);
                }
              });
            });
        }
    });
};

注意此功能将旋转的图像上传到同一个存储桶,但您可以轻松更改它.如果你只是用AWS LAMBDA开始,我建议你更多地了解它(https://www.youtube.com/watch?v=eOBq__h4OJ4,https://www.youtube.com/watch?v=PEatXsXIkLc)

确保您具有正确的权限(读取和写入),正确的功能触发器,在创建功能时更正"处理程序"!确保在CloudWatch中检查功能日志,使调试更容易.如果它开始超时,增加功能超时并增加它的内存.