Jump to content

Erroneously preserving EXIF across "flat" formats


Recommended Posts

I needed to remove EXIF rotation data from a photo I took with my phone, so I fired up paint.net and proceeded to open the .jpg, save it as .bmp and then save it again as .jpg. To my surprise, the data was still there.

 

Make: SAMSUNG

Camera Model Name: GT-I9300
Software: paint.net 4.0.1
Modify Date: 2014:07:15 01:07:29
3 hours, 28 minutes, 59 seconds ago
Y Cb Cr Positioning: Centered
Exposure Time: 1/17
F Number: 2.60
Exposure Program: Aperture-priority AE
ISO: 125
Exif Version: 0220
Date/Time Original: 2014:07:15 01:07:29
3 hours, 28 minutes, 59 seconds ago
Create Date: 2014:07:15 01:07:29
3 hours, 28 minutes, 59 seconds ago
Components Configuration: Y, Cb, Cr, -
Shutter Speed Value: 1/17
Aperture Value: 2.60
Brightness Value: 1.42578125
Exposure Compensation: 0
Max Aperture Value: 2.6
Metering Mode: Center-weighted average
Flash: No Flash
Focal Length: 3.7 mm
User Comment: (4,096 bytes binary data)
Flashpix Version: 0100
Color Space: sRGB
Image Size: 2,048 × 1,152
Interoperability Index: R98 - DCF basic file (sRGB)
Interoperability Version: 0100
Exposure Mode: Auto
Resolution: 96 pixels/inch
White Balance: Auto
Scene Capture Type: Standard
Orientation: Rotate 90 CW <-- REASON WHY I WAS DOING THIS
X Resolution: 72
Y Resolution: 72

generated by http://regex.info/exif.cgi

 

However, when I tried opening the .bmp from scratch and saving as .jpg, it worked as intended, i.e the new .jpg had almost no EXIF.

 

I'm pretty sure paint.net shouldn't have kept the EXIF through the .bmp. Am I wrong in that?

Link to comment
Share on other sites

Did you re-open the image after you saved it as a BMP? Paint.NET doesn't dump the EXIF data from memory when you save.

 

Also, what version of Paint.NET are you using? In 4.0, the rotation metadata is now honored when you open an image and then it's discarded when you save (to avoid an obvious double-rotation bug).

The Paint.NET Blog: https://blog.getpaint.net/

Donations are always appreciated! https://www.getpaint.net/donate.html

forumSig_bmwE60.jpg

Link to comment
Share on other sites

Paint.NET 4.0.1.

 

Here's exactly what I did:

 

  1. Open original.jpg
  2. Save as flat.bmp
  3. Save as flat.jpg

Here I discovered that flat.jpg still had EXIF. Now, without closing Paint.NET nor flat.jpg (or doing anything else in it, for that matter):

 

  1. Open flat.bmp
  2. Save as flat.jpg

Here I checked that flat.jpg didn't have EXIF anymore.

 

 

 

Paint.NET doesn't dump the EXIF data from memory when you save.

 

Yeah, that's what I figured. However, I expected that, once I saved the .jpg as .bmp, it would be as if I had closed the .jpg and just opened the .bmp. Scratching all the previous context, that is. Don't you agree that's a fair expectation?

 

Regards.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...