How to upload files by hiding identity

File Metadata:

Every file has metadata and basically metadata is just the file information that explains about the file. Let us consider this image file and its metadata as follows:

Image:

name.jpg

Metadata:

  • File Name : name.jpg Directory : . File Size : 1692 kB File Modification Date/Time : 2018:10:27 22:18:53+05:30 File Access Date/Time : 2018:10:27 23:08:17+05:30 File Inode Change Date/Time : 2018:10:27 23:07:55+05:30 File Permissions : rw-r--r-- File Type : JPEG File Type Extension : jpg MIME Type : image/jpeg Exif Byte Order : Big-endian (Motorola, MM) Modify Date : 2018:07:24 14:06:25 GPS Img Direction : 218 GPS Date Stamp : 2018:07:24 GPS Img Direction Ref : Magnetic North GPS Time Stamp : 08:36:23 GPS Altitude Ref : Unknown (2.2) Camera Model Name : Le X526 Y Cb Cr Positioning : Centered Resolution Unit : inches Y Resolution : 72 Software : s2-user 6.0.1 IIXOSOP5801910121S 44 release-keys Color Space : sRGB Create Date : 2018:07:24 14:06:25 F Number : 2.2 Focal Length : 3.7 mm Aperture Value : 2.2 Exposure Mode : Auto Sub Sec Time Digitized : 109920 Exif Image Height : 3264 Focal Length In 35mm Format : 4 mm Scene Capture Type : Standard Scene Type : Directly photographed Sub Sec Time Original : 109920 Exposure Program : Not Defined White Balance : Auto Exif Image Width : 2448 Sub Sec Time : 109920 Shutter Speed Value : 1/509 Metering Mode : Center-weighted average Date/Time Original : 2018:07:24 14:06:25 Components Configuration : Y, Cb, Cr, - Flash : Off, Did not fire Exif Version : 0220 Interoperability Index : R98 - DCF basic file (sRGB) Interoperability Version : 0100 Brightness Value : 0 ISO : 100 Sensing Method : One-chip color area Flashpix Version : 0100 Exposure Time : 1/509 X Resolution : 72 Make : LeMobile Thumbnail Length : 18926 Thumbnail Offset : 940 Compression : JPEG (old-style) Image Width : 2448 Image Height : 3264 Encoding Process : Baseline DCT, Huffman coding Bits Per Sample : 8 Color Components : 3 Y Cb Cr Sub Sampling : YCbCr4:2:0 (2 2) Aperture : 2.2 GPS Date/Time : 2018:07:24 08:36:23Z Image Size : 2448x3264 Megapixels : 8.0 Scale Factor To 35 mm Equivalent: 1.1 Shutter Speed : 1/509 Create Date : 2018:07:24 14:06:25.109920 Date/Time Original : 2018:07:24 14:06:25.109920 Modify Date : 2018:07:24 14:06:25.109920 Thumbnail Image : (Binary data 18926 bytes, use -b option to extract) Circle Of Confusion : 0.028 mm Field Of View : 154.9 deg Focal Length : 3.7 mm (35 mm equivalent: 4.0 mm) Hyperfocal Distance : 0.22 m Light Value : 11.3

We can get this data by using a tool called exiftool.

The command we have to use to get the details is:

'exiftool <filename>'

Unnecessary data sharing:

As we can observe, the image has lot of metadata which includes the software used, camera model, gps data etc.. Basically we always want to share the image but not the other unnecessary details which can result in tracking us. So how can we escape from this? Yeah, here is a trick for people like us who want to share their picture not the data. Use the same exif tool to remove all the metadata by hitting the following command:

$exiftool -all= <image name>

eg: exiftool -all =name.jpg

This command will removes all the metadata and now the metadata is follows:

  • File Name : name.jpg Directory : . File Size : 1673 kB File Modification Date/Time : 2018:10:27 23:50:19+05:30 File Access Date/Time : 2018:10:27 23:50:19+05:30 File Inode Change Date/Time : 2018:10:27 23:50:19+05:30 File Permissions : rw-r--r-- File Type : JPEG File Type Extension : jpg MIME Type : image/jpeg Image Width : 2448 Image Height : 3264 Encoding Process : Baseline DCT, Huffman coding Bits Per Sample : 8 Color Components : 3 Y Cb Cr Sub Sampling : YCbCr4:2:0 (2 2) Image Size : 2448x3264 Megapixels : 8.0

As we can observe that there is drastic change in the metadata of that image file. The above technique can be used for all types of files and I assume this technique will give us an added privacy.

Note: Only few websites are automatically removing the metadata while uploading but not all.


Last update: June 3, 2020