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It's True, Following the Ethernet Cable Can Lead to Your Location: Just One Picture is Enough

Introduction

With just one picture, how can you find the location and time of capture without leaving your home? In fact, every time you take a photo, your phone or camera saves an image file (usually JPEG) on the device. This file not only contains all the visible pixels but also includes a wealth of image EXIF metadata.

What is EXIF Data

EXIF stands for Exchangeable Image File Format, which is a metadata format used for embedding information in digital images. EXIF data records the shooting information and related technical data of a photo. The following table shows some of the EXIF information.

EXIF Description Sample Output
Make Camera maker Apple
Model Camera model iPhone 11
ExposureTime Exposure time 1/60
ExposureProgram Exposure program Normal program
ISOSpeedRatings ISO speed 160
ApertureValue Aperture value 1.8
ExposureBiasValue Exposure bias 0
Flash Flash status Flash did not fire,compulsory flash mode
FocalLength Focal length 4.25 mm
ExposureMode Exposure mode Auto exposure
LensModel Lens model iPhone 11 back dual wide camera 4.25mm f/1.8

These pieces of information provide detailed data about the shooting device, exposure settings, and lens information. For photography enthusiasts and professional photographers, they are valuable for understanding the shooting conditions and technical parameters of a photo.

However, some EXIF data may also contain privacy information that you may not want to expose, such as GPS-related information at the time of shooting. The following table shows some of the GPS information that can be obtained from EXIF.

EXIF Description Sample Output
GPS Info IFD Pointer Pointer position for GPS information storage 2090
GPSLatitude Latitude value 14.35716389
GPSLongitude Longitude value 100.5653306
GPSAltitude Altitude value 0.432788587534304 m
GPSSpeed Speed value 0.066762067
GPSImgDirection Image direction value 129.419281
GPSDestBearing Destination bearing value 129.419281
GPSDateStamp GPS date 2023:05:01
GPSHPositioningError Horizontal positioning error 5.026539358

How to Obtain EXIF Data

With the popularity of mobile devices and the continuous evolution of GPS technology, location services have become more accurate. Most smartphones record GPS coordinates when taking photos. Therefore, if you upload photos with metadata to social media or send them by e-mail, although there is usually no problem, malicious people can collect a lot of detailed information from them. Earlier, an article titled "How I Reasoned out Wang Luodan's Address" became popular on the internet, and the author used photos of Wang Luodan on social network platform to reason out his address information in just 40 minutes. Today, with an EXIF extraction tool, one can obtain this information quickly, even deduce the height of the building based on the height information.

You can use the exif-cli command-line tool to extract EXIF information:

  1. you need to install Node.js, which can be downloaded and installed from the Node.js website.

  2. Install exif-cli globally by the following command:

npm install -g exif-cli
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  1. Change the directory to the location of the target image and enter the following command in the terminal after opening it:
exif example.jpg
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The final result is as follows:

PS C:\Users\rance\Pictures> exif example.jpg

image
  Make: Apple
  Model: iPhone 11
  Orientation: 1
  XResolution: 72
  YResolution: 72
  ResolutionUnit: 2
  Software: 16.3.1
  ModifyDate: 2023:05:01 18:41:33
  HostComputer: iPhone 11
  ExifOffset: 216
  GPSInfo: 2090

exif
  ExposureTime: 0.016666666666666666
  FNumber: 1.8
  ExposureProgram: 2
  ISO: 160
  ExifVersion: 0232
  DateTimeOriginal: 2023:05:01 18:41:33
  CreateDate: 2023:05:01 18:41:33
  ShutterSpeedValue: 5.915630896403007
  ApertureValue: 1.6959938128383605
  BrightnessValue: 3.0061857632280167
  ExposureCompensation: 0
  MeteringMode: 3
  Flash: 16
  FocalLength: 4.25
  SubjectArea: 2559,2283,740,775
  SubSecTimeOriginal: 676
  SubSecTimeDigitized: 676
  ColorSpace: 65535
  ExifImageWidth: 4032
  ExifImageHeight: 3024
  SensingMethod: 2
  SceneType:
  ExposureMode: 0
  WhiteBalance: 0
  DigitalZoomRatio: 1.9947229551451187
  FocalLengthIn35mmFormat: 52
  LensInfo: 1.5399999618512084,4.25,1.8,2.4
  LensMake: Apple
  LensModel: iPhone 11 back dual wide camera 4.25mm f/1.8

gps
  GPSLatitudeRef: N
  GPSLatitude: 14,21,25.79
  GPSLongitudeRef: E
  GPSLongitude: 100,33,55.19
  GPSAltitudeRef: 1
  GPSAltitude: 0.43278858753430416
  GPSSpeedRef: K
  GPSSpeed: 0.06676206737914926
  GPSImgDirectionRef: T
  GPSImgDirection: 129.41928104575163
  GPSDestBearingRef: T
  GPSDestBearing: 129.41928104575163
  GPSDateStamp: 2023:05:01
  GPSHPositioningError: 5.026539357943012
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Although exif-cli can obtain exif data, it is cumbersome to use, requires configuration of related dependencies, and lacks an easy-to-interact UI interface. To solve this problem, He3 provides a visual EXIF extraction tool.

He3's EXIF extraction tool not only extracts EXIF information but also categorizes data on different focal points. Perhaps you want to uncover the magical secrets behind these stunning photos and explore how they were born. Maybe you are eager to know the exact location of those picturesque places so you can visit them in person, and He3's EXIF extraction tool is just what you need! Whether it's shooting time, camera model, or exposure parameters, this built-in tool in He3 can present them all for you.

Image description

Experience He3's image EXIF extraction tool now: https://t.he3app.com/fns5

How to clear EXIF information

It should be noted that since EXIF data is embedded in image files, it may pose privacy and security risks. For example, when sharing photos on social media or online, location information in EXIF data can reveal a person's actual location. Therefore, we need to be cautious when sharing photos with EXIF data and make appropriate processing and deletion when necessary. In fact, EXIF data can be considered as "redundant information" of the image, and removing it will not affect the actual pixels of the image. After testing, He3's image EXIF extractor tool can remove sensitive information in the image, thus protecting your privacy.

Image description

After removing the EXIF information from the sample image, it can be seen that the information has been cleared when inputting it back into the EXIF extractor.

Try it yourself

Perhaps you are not satisfied with being an observer. In He3's tool library, there is also a lightweight EXIF editor for you to make simple edits to EXIF information.

In fact, editing EXIF information often requires a lot of professional knowledge to ensure the correctness of EXIF format. For example, the format of storing EXIF in images taken with Android and iOS systems is different, and the format of storing EXIF in images on different devices under the same system is also different. Therefore, we have retained as many popular focal points as possible for you to edit.

Experience He3's image EXIF editor tool now: https://t.he3app.com/2m3r

Perhaps you want to ask

  1. Can the shooting location of the photo be found? It can be found, but the prerequisite is that the image has GPS location data. Upload it to He3, and you'll know. If you turn off GPS positioning in your phone settings, the photo will not contain GPS data.
  2. Is EXIF data guaranteed to be true? Not necessarily, as there are currently multiple ways to modify photo metadata. It is impossible to ensure that you are viewing the original image metadata or metadata that has been edited by someone else.
  3. Is it safe to upload images to He3? He3 will not engage in any privacy-infringing behavior. For example, in He3's image EXIF extraction tool, the images you upload will not be stored and are only used for extracting and visualizing metadata.
  4. Is there a charge? This tool is provided completely free of charge. In addition, He3 also provides more than 400 other free tools for you to use.

Learn more

Feel free to download the latest version of the He3 client or update your version to 1.3.7 and experience it. Use He3 to unleash your modern development potential. Official website: https://he3.app/

f you have any ideas or suggestions on how we can use our tools to improve your work efficiency, feel free to raise issues and discuss with us: https://github.com/he3-app/he3-feedback/issues

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