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Background

Hello, I was able to recover some images from a broken hard drive. Some of the images seem to have some binary data in the UserComment tag and I was wondering if it could be Lat/Long data?

This image was taken with a Samsung Galaxy S4 android phone in 2015.

Question

How can I figure out or troubleshoot what this binary data could be?

Data

Extracted using IrfanView x64 on a Windows 10 machine.

Filename - 20150305_193403.jpg
ImageWidth - 3264
ImageLength - 2448
Make - SAMSUNG
Model - SCH-I535
Orientation - Right top
XResolution - 72
YResolution - 72
ResolutionUnit - Inch
Software - I535VRUDNE1
DateTime - 2015:03:05 19:34:02
YCbCrPositioning - Centered
ExifOffset - 242
ExposureTime - 1/30 seconds
FNumber - 2.60
ExposureProgram - Aperture priority
ISOSpeedRatings - 200
ExifVersion - 0220
DateTimeOriginal - 2015:03:05 19:34:02
DateTimeDigitized - 2015:03:05 19:34:02
ComponentsConfiguration - YCbCr
ShutterSpeedValue - 1/30 seconds
ApertureValue - F 2.60
BrightnessValue - 1.89
ExposureBiasValue - 0.00
MaxApertureValue - F 2.60
MeteringMode - Center weighted average
LightSource - Auto
Flash - Not fired
FocalLength - 3.70 mm
UserComment - �  �       4xV4xV4xV4       ` ��
 ��     ��ٌ     �                         ��                                                                                                                                                                                                                  C A L ZHFJ02    Cur.ZHFJ02CML 018001001509FD1301090201010D011601160967� +��&      T U N A  ������     
� � H^�����������. �  >     �����   FLFL SVN#g                                    
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 3264
ExifImageHeight - 2448
InteroperabilityOffset - 4912
SensingMethod - One-chip color area sensor
SceneType - A directly photographed image
ExposureMode - Auto
White Balance - Auto
SceneCaptureType - Standard

GPS information: - 
GPSVersionID - 2.2.0.0

Maker Note (Vendor): - 

Thumbnail: - 
ImageWidth - 160
ImageLength - 120
Compression - 6 (JPG)
Orientation - Right top
XResolution - 72
YResolution - 72
ResolutionUnit - Inch
JpegIFOffset - 5090
JpegIFByteCount - 4411
2

It's most likely junk. GPS data would have been stored in the GPS tags.

Looking at a sample image using exiftool with the -v3 option gives a hex dump of the UserComment

| | 17) UserComment = ASCII..V.(.xV4.xV4.xV4.xV4..`^z...c.....$9...CALZDFE02Cur.ZDFI0[snip]
  | |     - Tag 0x9286 (4096 bytes, undef[4096]):
  | |         1352: 41 53 43 49 49 00 00 00 00 00 00 00 0f 0a 00 00 [ASCII...........]
  | |         1362: 56 08 00 00 28 04 00 00 78 56 34 12 78 56 34 12 [V...(...xV4.xV4.]
  | |         1372: 78 56 34 12 78 56 34 12 00 00 00 00 00 00 03 00 [xV4.xV4.........]
  | |         1382: 60 00 5e 7a 05 00 e8 04 63 06 00 00 0b 00 00 00 [`.^z....c.......]
  | |         1392: ff ff 08 24 39 00 00 00 00 00 84 00 00 00 00 00 [...$9...........]
  | |         [snip 4016 bytes]

The first 8 bytes are used to indicate which character code the UserComment is used. In this case it is ASCII followed by 3 null bytes. See EXIF standard page 50 (via Archive.org). The very next byte would be the start of the UserComment text, which is a null byte, indicating the end of the text. In other words, it's a 0 length string.

The rest is just junk padding. Many cameras simplify their writing algorithms by allowing variable-sized information to be written at fixed offsets in the output image. Note that this sample image I used has some of the same xV4 bytes as shown in your Irfanview output. If I tell exiftool to copy the EXIF data, it drops all that extra padding. See exiftool FAQ #13a for details

  | | 17) UserComment = ASCII
  | |     - Tag 0x9286 (8 bytes, undef[8]):
  | |         0b46: 41 53 43 49 49 00 00 00                         [ASCII...]

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