什么是图像Hash用？ [英] What is image hashing used for?
问题描述
我听到这个词有时也和我想知道它是干什么用的呢？
I hear this term sometimes and am wondering what it is used for?
推荐答案
虽然通常散列文件散列文件的数据的各个位，图像哈希工作在一个稍高的水平。所不同的是，与图像散列，如果两个图像看起来几乎相同，但位于不同的格式，或分辨率（或有轻微的损坏，可能是由于玉米pression）它们应散列到相同的编号。尽管他们的数据被完全不同，如果它们看起来parctically相同于人的实际比特，它们散列为相同的事情。
While normally hashing a file hashes the individual bits of data of the file, image hashing works on a slightly higher level. The difference is that with image hashing, if two pictures look practically identical but are in a different format, or resolution (or there is minor corruption, perhaps due to compression) they should hash to the same number. Despite the actual bits of their data being totally different, if they look parctically identical to a human, they hash to the the same thing.
这方面的一个应用就是搜索。 TinEye.com允许你上传的图片，并发现它的许多出现在互联网上。像谷歌，它有一个网络爬虫爬行通过网页和查找图像。然后，它散列这些图像，并存储在数据库中的哈希和网址。当你上传一张图片，它只是计算散列和检索所有链接到该哈希数据库的URL。 TinEye样品用途包括查找图片的分辨率更高的版本，或者找到一个公共的Facebook / MySpace的/等。从他们的图像文档（假设这些配置文件都使用相同的照片。
One application of this is search. TinEye.com allows you to upload an image and find many of its occurrences on the internet. like google, it has a web crawler that crawls through web pages and looks for images. It then hashes these images and stores the hash and url in a database. When you upload an image, it simply calculates the hash and retrieves all the urls linking to that hash in the database. Sample uses of TinEye include finding higher resolution versions of pictures, or finding someone's public facebook/myspace/etc. profile from their picture (assuming these profiles use the same photo.
图像散列也可以使用与高速缓存或本地存储的照片的副本或存储，分别prevent重传。
Image hashing can also be used with caching or local storage to prevent retransmission of a photo or storage of duplicates, respectively.
有许多其他的可能性，包括图像认证并找到一个类似的视频帧（如提及由别人）。
There are plenty of other possibilities including image authentication and finding similar frames in a video (as was mentioned by someone else).
这篇关于什么是图像Hash用？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！
