Need Some Technical Advice on Erradicating Meta-data.
Patrick, Sun Nov 27 2016, 09:02PMFirst, Im not a criminal.
Second, Im not planning any criminal acts.
Third, Im not planning any terrorist attacks.
Background:
So Im a volunteer for a company that does high altitude (+100,000 ft) research. Im allowed to take as many pictures as I want, of anything for personal use. But Im only allowed to publish some of what I know, due to funding partners and intellectual property concerns.
We've also had occasions where well meaning people have followed us into the desert and gotten lost. So were more secretive about locations and dates of flights now.
Question:
When I take pictures with my new camera, I can see all kinds of data in the properties window. But what about hidden data ? I need to obliterate all data except the image pixels themselves. Will going into a photo application of my choice, doing my changes, then saving as a different jpeg (not saving over the original) be enough ? Else how am I to accomplish this need.
Ive seen programs like "EXIF Purge" but dont know if thats a great idea or not.
I may post a secret pic for some of you I trust in a special location for a limited time, youll be able to test my method that way.
Re: Need Some Technical Advice on Erradicating Meta-data.
Avalanche, Sun Nov 27 2016, 09:12PM
The way i'd do it:
Open the original JPG, save as .PNG (lossless, and has no metadata)
Open the .PNG, save as a new .JPG
That should pretty much guarantee nothing slips through...?
Avalanche, Sun Nov 27 2016, 09:12PM
The way i'd do it:
Open the original JPG, save as .PNG (lossless, and has no metadata)
Open the .PNG, save as a new .JPG
That should pretty much guarantee nothing slips through...?
Re: Need Some Technical Advice on Erradicating Meta-data.
Bjørn, Mon Nov 28 2016, 01:22AM
.PNG has metadata so converting to it is not a 100% safe method since the result will depend on the program you use.
In windows 10 you can right click on an image and go to
Bjørn, Mon Nov 28 2016, 01:22AM
.PNG has metadata so converting to it is not a 100% safe method since the result will depend on the program you use.
In windows 10 you can right click on an image and go to
Properties/Details tab/Remove Properties and Personal InformationPrograms like GIMP and Photoshop can save files without the metadata.
Re: Need Some Technical Advice on Erradicating Meta-data.
Carbon_Rod, Mon Nov 28 2016, 05:56AM
"Photoshop can save files without the metadata"
Adobe uses watermarks instead.
Carbon_Rod, Mon Nov 28 2016, 05:56AM
"Photoshop can save files without the metadata"
Adobe uses watermarks instead.
Re: Need Some Technical Advice on Erradicating Meta-data.
Kizmo, Mon Nov 28 2016, 06:37AM
Internet is full of Exif metadata removal services but i prefer downloadable solution such as this one:
I can confirm, this one works fine :)
EDIT:
Whatever removal software or website you choose, you can test the success with this website:
Kizmo, Mon Nov 28 2016, 06:37AM
Internet is full of Exif metadata removal services but i prefer downloadable solution such as this one:
I can confirm, this one works fine :)
EDIT:
Whatever removal software or website you choose, you can test the success with this website:
Re: Need Some Technical Advice on Erradicating Meta-data.
Hydron, Mon Nov 28 2016, 09:56AM
Irfanview has some handy options for metadata when you save a file.
The other way to deal with it would be simply to open the file, ctrl+c to copy the image, paste it into another program/window (as raw pixels from the clipboard, no metadata involved), save it as a new .jpg. For the web you're probably going to recompress the image anyway so wouldn't even lose any quality vs working directly with the original.
Hydron, Mon Nov 28 2016, 09:56AM
Irfanview has some handy options for metadata when you save a file.
The other way to deal with it would be simply to open the file, ctrl+c to copy the image, paste it into another program/window (as raw pixels from the clipboard, no metadata involved), save it as a new .jpg. For the web you're probably going to recompress the image anyway so wouldn't even lose any quality vs working directly with the original.
Re: Need Some Technical Advice on Erradicating Meta-data.
Dr. Slack, Mon Nov 28 2016, 04:46PM
If the image is low enough resolution to fit on the screen, display it and take a screenshot.
You could use something like python's image library which allows you to programmatically read/write/fake/destroy side data to your heart's content.
Dr. Slack, Mon Nov 28 2016, 04:46PM
If the image is low enough resolution to fit on the screen, display it and take a screenshot.
You could use something like python's image library which allows you to programmatically read/write/fake/destroy side data to your heart's content.
Re: Need Some Technical Advice on Erradicating Meta-data.
Patrick, Mon Jan 23 2017, 01:27AM
Ok Ive got quite a few pics up now, I didnt eradicate all the meta data. but for those who want to see here is the site :
If you want to look for errors or other troublesome mistake please do id be grateful.
When "Tech TV" was around here in the US, one of the hosts, (beautiful i will say) uploaded a normal pic, but someone out there went through it a found a low res thumbnail, of an undressed nature she had taken of herself.
I dont know how that could happen, but it did. And if i screw up some intellectual property rights my group will kill me, as we've had others steal our work before.
Patrick, Mon Jan 23 2017, 01:27AM
Ok Ive got quite a few pics up now, I didnt eradicate all the meta data. but for those who want to see here is the site :
If you want to look for errors or other troublesome mistake please do id be grateful.
When "Tech TV" was around here in the US, one of the hosts, (beautiful i will say) uploaded a normal pic, but someone out there went through it a found a low res thumbnail, of an undressed nature she had taken of herself.
I dont know how that could happen, but it did. And if i screw up some intellectual property rights my group will kill me, as we've had others steal our work before.
Re: Need Some Technical Advice on Erradicating Meta-data.
Bjørn, Mon Jan 23 2017, 05:21AM
JPEG files can contain lower resolution copies to speed up preview and thumbnail generation. If you crop the original picture in a program that does not regenerate the lower resolution picture then you can end up with the full body in one picture and a head in the other. Post it on the internet and it will just take seconds before someone finds out.
Bjørn, Mon Jan 23 2017, 05:21AM
JPEG files can contain lower resolution copies to speed up preview and thumbnail generation. If you crop the original picture in a program that does not regenerate the lower resolution picture then you can end up with the full body in one picture and a head in the other. Post it on the internet and it will just take seconds before someone finds out.
Re: Need Some Technical Advice on Erradicating Meta-data.
Plasma, Mon Jan 23 2017, 05:24AM
@Patrick
Modern camera put a 4 byte hex value in the file, that is tired to the camera, open photo's from the camera in a hex editor and see what values are the same in different pics, replace with 0x00000000, and then see if you can still see the picture.
Plasma, Mon Jan 23 2017, 05:24AM
@Patrick
Modern camera put a 4 byte hex value in the file, that is tired to the camera, open photo's from the camera in a hex editor and see what values are the same in different pics, replace with 0x00000000, and then see if you can still see the picture.
Re: Need Some Technical Advice on Erradicating Meta-data.
Conundrum, Sun Jan 29 2017, 06:05PM
Interestingly, this has shown up as a way to protect journalists in particularly dangerous areas, sending pictures of atrocities/Government civil rights abuses/etc. Or factory workers whistleblowing dangerous working conditions, etc.
Conundrum, Sun Jan 29 2017, 06:05PM
Interestingly, this has shown up as a way to protect journalists in particularly dangerous areas, sending pictures of atrocities/Government civil rights abuses/etc. Or factory workers whistleblowing dangerous working conditions, etc.
Print this page