Images *can* be protected.

[Kyler Laird]

Back in the early/mid 1990s, it seemed like there was regularly a
question like "How can I make images available on the Web without
letting people steal them?" I laughed. I'm not laughing now.

While I wasn't looking, browsers apparently became stupid. I can
have an image staring at me in my browser but I can't save it.
All of the GUI browsers that I and my friends have tried are
similarly affected.

Grrr...

Here's a trivial example.
http://lairds.us/temp/image

Anyone know of a simple workaround? A Mozilla plugin (or just a
fix) would be great.

Pointers to discussions on the topic will also be appreciated.
I'm not having much luck with searches. I've found several
mentions of downloading a displayed image again, but no
explanations or workarounds for it.

Thank you.

--kyler

[Klaus Johannes Rusch]

Post by Kyler Laird
While I wasn't looking, browsers apparently became stupid. I can
have an image staring at me in my browser but I can't save it.
All of the GUI browsers that I and my friends have tried are
similarly affected.
Grrr...
Here's a trivial example.
http://lairds.us/temp/image
Anyone know of a simple workaround? A Mozilla plugin (or just a
fix) would be great.

Use the LiveHeaders plugin for Firefox to look at the request/response:

POST /temp/image HTTP/1.1
Host: lairds.us
Referer: http://lairds.us/temp/image
Content-Type: application/x-www-form-urlencoded
Content-Length: 0

HTTP/1.x 200 OK
Date: Wed, 23 Jun 2004 07:09:45 GMT
Transfer-Encoding: chunked
Content-Type: image/jpeg

The returned content is a JPEG image. You can either capture the
datastream directly, or use a local proxy server on your machine to save
all retrieved content for later use.

[Kyler Laird]

...

Post by Klaus Johannes Rusch
The returned content is a JPEG image. You can either capture the
datastream directly, or use a local proxy server on your machine to save
all retrieved content for later use.

Oh, *I* can handle that without much of a problem. (It's a fairly
simple but tedious matter to write a Python script or use wget to
do it.) However I'm looking for a method I can tell other people
to use when encountering such a situation - something that can be
done through a common browser.

Incidentally, one of my friends figured out that Galeon will allow
the user to "view source" of an image. *That* can then be saved
but we determined that the "view source" operation also reloads the
image. (That's why I threw a bunch of images at the example and
serve them randomly. The saved image is likely to be different
than the viewed image.)

Mozilla and Konqueror are too clever to allow viewing the source
of an image.

Firefox gets *really* weird. It allows viewing of the "source" of
the image and it looks like the JPEG data. However, saving the
"source" results in a file containing the HTML of the form for the
page (the result of a GET request). I tried cutting and pasting
the JPEG data but I didn't get far.

--kyler

[Klaus Johannes Rusch]

Post by Kyler Laird
Oh, *I* can handle that without much of a problem. (It's a fairly
simple but tedious matter to write a Python script or use wget to
do it.) However I'm looking for a method I can tell other people
to use when encountering such a situation - something that can be
done through a common browser.

Set the memory cache size to zero, and the disk cache size to non-zero.
Load the image, check the cache file name in about:cache and rename that
file.

Another option would be to use a non-graphical browser, lynx will prompt
to save the image to disk when submitting the form.

[Doc O'Leary]

Post by Kyler Laird
Oh, *I* can handle that without much of a problem. (It's a fairly
simple but tedious matter to write a Python script or use wget to
do it.) However I'm looking for a method I can tell other people
to use when encountering such a situation - something that can be
done through a common browser.

Right click and "Save Image As..." works just fine for me. Or just
doing a save of the window, since all it is displaying is the image. I
use Safari on the Mac.

[David Dorward]

Post by Kyler Laird
Here's a trivial example.
http://lairds.us/temp/image
Anyone know of a simple workaround?

Take a screenshot.

[Kyler Laird]

Post by David Dorward

Post by Kyler Laird
Here's a trivial example.
http://lairds.us/temp/image
Anyone know of a simple workaround?

Take a screenshot.

The question is how to get a copy of the original image, not the browser's
(limited) rendition of it.

--kyler

[David Dorward]

Post by Kyler Laird

Post by David Dorward
Take a screenshot.

The question is how to get a copy of the original image, not the browser's
(limited) rendition of it.

The browser's rendition is not all that limited.

[Kyler Laird]

Post by David Dorward

Post by Kyler Laird

Post by David Dorward
Take a screenshot.

The question is how to get a copy of the original image, not the browser's
(limited) rendition of it.

The browser's rendition is not all that limited.

Well, let's dispense with the trivial examples and jump right
to the real application that got me stuck on this.

Show me your screenshots for this data file
http://aviationtoolbox.org/tmp/GPS_01.dat
rendered with this tool
https://aviationtoolbox.org/Members/kyler/tools/trip_plot
at 50% and 100% scale.

Then tell me how well screenshots capture georeferencing and
EXIF data.

--kyler

[Doc O'Leary]

Post by Kyler Laird
Show me your screenshots for this data file
http://aviationtoolbox.org/tmp/GPS_01.dat
rendered with this tool
https://aviationtoolbox.org/Members/kyler/tools/trip_plot
at 50% and 100% scale.

Again, how is that supposed to be a challenge? Safari allows me to
simply save everything in question. The checksums for the different
pieces:

MD5(GPS_01.dat)= 9221d40450eb2d406ee7846e4cd0a9f3
MD5(foo100.jpg)= a3032f953468652a3e300a14e2ad5697
MD5(foo50.jpg)= 123e092c552eb777ae4ca9f687bee76d

Post by Kyler Laird
Then tell me how well screenshots capture georeferencing and
EXIF data.

I see no EXIF data in the generated images, and I'm not sure what
georeferencing is. Is there a bug in Safari (or my image viewer)
regarding EXIF, or are you simply trying to refute the utility of a
screenshot by using a 4714x1996 image?

[Kyler Laird]

Post by Doc O'Leary
Again,

Oh?

Post by Doc O'Leary
how is that supposed to be a challenge?

It's a challenge to those of us using browsers that can't do it.

Post by Doc O'Leary
Safari allows me to
simply save everything in question.

Ah! That's what I wanted to know. I'm happy to hear that Safari is
smart enough to handle it. Too bad it's not multi-platform.

Maybe this example will be useful in encouraging other browser groups
to improve. Thank you for the data point.

Post by Doc O'Leary
I see no EXIF data in the generated images, and I'm not sure what
georeferencing is. Is there a bug in Safari (or my image viewer)
regarding EXIF, or are you simply trying to refute the utility of a
screenshot by using a 4714x1996 image?

There isn't any such data in those images yet. I was just following
up on the useless suggestion of using screenshots.

--kyler