使用JavaScript提取EXIF数据 [英] Extracting EXIF data with JavaScript
问题描述
我正在评估针对移动Web应用程序使用Canvas的图像上传技术.症结在于读取客户端的EXIF数据.此站点上的其他讨论点向出色的 Blueimp JavaScript图像加载 .我特别想从EXIF中提取:
I'm evaluating image upload techniques using Canvas for a mobile web app. The sticking point is reading EXIF data client-side. Other discussions on this site point towards the excellent Blueimp JavaScript Image Load. I particularly want to extract from EXIF:
- 日期&拍照时间
- 地理位置-纬度拍摄照片的经度
使用在iPhone上拍摄的照片(带有地理数据)在Windows Vista的Firefox v.33.1上测试Blueimp脚本，它成功提取了所有EXIF数据，包括日期，时间和日期.地理坐标.在iOS上对相同照片运行相同测试，它仅提取少量EXIF数据-仅提取尺寸和方向(我使用的是iPhone 5，iOS 8.1)， 没有其他的.为什么是这样?是否有推荐的修补程序或替代JavaScript EXIF提取工具?
Testing the Blueimp script on Firefox v.33.1 on Windows Vista using a photo taken on an iPhone (with geo data), it successfully extracts all the EXIF data including date, time & geocoords. Running the same test with the same photo on iOS and it only extracts a tiny amount of EXIF data - just the dimensions and orientation (I'm using iPhone 5, iOS 8.1), nothing else. Why is this? Is there a fix or an alternative JavaScript EXIF extraction tool to recommend?
很高兴收到我的建议，因为这正在引起我的注意！！预先感谢.
Suggestions very gratefully received as this is doing my head in!! Thanks in advance.
请注意:我不想在PHP的服务器端执行此操作，因为这需要上传完整的图像，这可能会降低移动带宽的速度，因此请使用canvas选项在客户端调整图像大小
推荐答案
After more reading around on this issue, a similar question was asked here a year ago, with no satisfactory responses. According to one commenter, uploaded files on iOS devices only get access to a sanitized version of the file for privacy reasons. This means what useful stuff like time/date and GPS is stripped out of a file before it is made available to the browser.
哪种想法挫败了这个想法.:(
Which kind of scuppers this idea. :(
这篇关于使用JavaScript提取EXIF数据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！
