MongoDB GridFS存储多种大小的图像或即时调整大小 [英] MongoDB GridFS store multiple sizes of image or use on the fly resizing

问题描述

在我的Web应用程序中，我正在使用MongoDB GridFS来存储用户上传的图像.

In my web app i'm using MongoDB GridFS to store user uploaded images.

该网站的其余部分由MySQL管理.

The rest of the site is managed by MySQL.

在一张照片表(在mysql中)中，我有三个字段用于存储文件对象的MongoId.

In a photo table (in mysql) I have three fields for storing the MongoId of the file object.

• 小
• 中
• 大

因此，我存储了图像的三个版本.大中小.

So I store three versions of the image. Small, medium and large.

我的问题是，有时我需要使用比图片的小"版本小的缩略图(例如，在小部件框中，消息头像等)，或者我需要使用略小的版本的缩略图.中等图片.

My question is, sometimes i'll need to use a thumbnail smaller than the 'small' version of the image (i.e. in a widget box, message avatars etc.) or i'll need to use a slighly smaller version of the medium image.

所以我的问题是，最好只将一张图像存储在GridFS系统中，然后在照片表中保留一个字段来存储MongoID，然后创建一个脚本来动态调整图像大小(即

So my question, would it better to just store one image in the GridFS system and then have one field in the photo table storing the MongoID and then create a script that resizes the image on the fly (i.e. http://localhost/image/fetch/{mongoid}?resize=50

否则，在我的数据库中，我将需要thumbnail_50，thumbnail_100，medium_300，medium_400等.

Otherwise, in my db i'll need thumbnail_50, thumbnail_100, medium_300, medium_400 etc. etc.

采用即时调整大小路线将意味着什么?这是一个坏主意还是一个好主意?你会怎么做?

What would be the implications of going down the on-the-fly resize route? is it a bad or a good idea? What would you do?

谢谢.

推荐答案

动态调整大小将导致服务器上的CPU负载比一次调整为各种大小并存储结果要多得多.另一方面，提前调整大小可能会导致将更大的数据集存储在GridFS中.换句话说，这是一个权衡.

Resizing on the fly will result in far more CPU load on your server than resizing to a variety of sizes once, and storing the results. On the other hand, resizing ahead of time may result in a larger set of data to be stored in GridFS. In other words, it's a tradeoff.

您可以考虑使用一种混合方法，您可以即时调整大小，然后将结果保存回GridFS，这样就无需将任何一个图像调整为给定大小的大小超过一次.

You could consider a hybrid approach, where you resize on the fly but save the results back to GridFS so that you don't need to resize any one image to a given size more than once.

您还应该知道HTML和CSS允许使用各种选项来控制图像的显示大小.例如:

You should also know that HTML and CSS allow various options for controlling the displayed size of an image. For example:

<img src="/path/to/image.jpg" width="50"/>

将导致图像按比例缩放到50像素宽(在大多数现代浏览器中，无论如何).您还可以使用width和max-width CSS属性来控制图像大小.

Will result in an image scaled proportionally to 50 pixels wide (in most modern browsers, at any rate). You can also use the width and max-width CSS properties to control image size.

对我自己来说，不知道要存储的图像的大小或文件大小，添加图像时我可能会调整大小-换句话说，只需一次点击页面速度和CPU负载-然后在特定情况下需要稍微不同的大小时，使用max-width控制屏幕大小，然后使用GridFS提供各种大小.

For myself, and knowing nothing about the volume or file size of the images you'll be storing, I'd probably resize when images are added -- in other words, take the page speed and CPU load hit once -- and then serve the various sizes out of GridFS, using max-width to control the on-screen size if a slightly different size is required in one particular case.

这篇关于MongoDB GridFS存储多种大小的图像或即时调整大小的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！