Newer cameras almost always add extra info in a
section of the .jpg file called the EXIF header.
This info is contained in .jpg picture files but isn't
necessary to display the picture. The info is just
extra baggage and can be deleted without
affecting the picture.
I looked into what info my camera adds to the
photos it records. Found out my camera adds
nothing. Yeah.
Some photo editing programs allow you to view,
edit, or delete this info. I found 2 free programs
to view and delete this info.
EXIF-O-Matic = displays exif info
JPG Cleaner = deletes exif info
Note, I have no affiliation with either of these
programs and they are just some tools I found
that seemed to work. There may be better
programs available for this but "free" always
sounds good to me.
As a test, I copied a sample photo from the
internet, lets call it Sample Before.jpg. I ran this
photo thru EXIF-O-Matic and copied the log
shown below...
EXIF info contained in Sample Before.jpg as
reported by EXIF-O-Matic Version 1.1.8
Sample Before.jpg - EXIF Information
- Exif
Make FUJIFILM
Model FinePix S1000fd
X Resolution 1/72 inches
Y Resolution 1/72 inches
Resolution Unit Inches
Software Digital Camera FinePix S1000fd Ver1.02
Date/Time 2009:05:21 21:38:45
YCbCr Positioning Datum point
Copyright
Exposure Time 1/34 sec
F-Number F2.8
Exposure Program Program normal
ISO Speed Ratings 800
Exif Version 2.20
Date/Time Original 2009:05:21 21:38:45
Date/Time Digitized 2009:05:21 21:38:45
Components Configuration YCbCr
Compressed Bits Per Pixel 3 bits/pixel
Shutter Speed Value 1/32 sec
Aperture Value F2.8
Brightness Value 5
Exposure Bias Value 0
Max Aperture Value F2.8
Metering Mode Multi-segment
Light Source Unknown
Flash Unknown (16)
Focal Length 5.9 mm
FlashPix Version 1.00
Color Space sRGB
Exif Image Width 480 pixels
Exif Image Height 640 pixels
Focal Plane X Resolution 1/1075 cm
Focal Plane Y Resolution 1/1075 cm
Focal Plane Resolution Unit cm
Sensing Method One-chip color area sensor
File Source Digital Still Camera (DSC)
Scene Type Directly photographed image
Compression JPEG compression
Orientation top, left side
Thumbnail Offset 1826 bytes
Thumbnail Length 7276 bytes
Thumbnail Data [7276 bytes of thumbnail data]
- FujiFilm Makernote
Makernote Version 0130
Quality ’
Sharpness Normal
White Balance Auto
Color Normal (STD)
Flash Mode Off
Flash Strength 50528272/365066 eV (Apex)
Macro On
Focus Mode Auto focus
Slow Synchro Off
Picture Mode Auto
Continuous Taking Or Auto Bracketting Off
Blur Warning Blur warning
Focus Warning Out of focus
AE Warning AE good
As you can see that's a lot of info, pretty much
useless unless you are a photography nut. I see
nothing in there like a serial number of the camera
or gps location where photo was taken so it's
pretty harmless. Except, it does take up space.
Ran the sample thru JPG Cleaner to remove all
header info and copied the log.
JPG Cleaner 95 v2.6 log...
Processing Sample Before...Cleaned 9094 bytes
Processed 1 file(s), 1 of them cleaned, 0 error(s).
Cleaned total of 9094 byte(s) in 0:00:00.
The cleaned file it created is slightly smaller
without all the useless header info. Cleaned file
was named Sample After.jpg
File Size comparison before & after cleaning
with JPG Cleaner...
131,635 bytes Sample Before.jpg
122,541 bytes Sample After.jpg
Ran Sample After.jpg thru EXIF-O-Matic and
copied this log...
Sample After.jpg - EXIF Information
- Exif
Yes, nice and clean now. The smaller file size
obviously takes up less disk space and also would
take slightly less time to load on a website or to
transmit by email. Attached are the before and
after photos so you can see there is no difference
in photo display.
I know .gif files can contain extra info too.
Not sure if other file formats might also contain
extra hidden info.
Cheers