Deconstruct a GIF file

On Wed, 07 Jun 2017 17:52:14 -0700, Savageduck
wrote:

That seems like a great plan since NONE of them have the layers I was
worried about!

I still don¢t quite understand your concern over layers which shouldn¢t
exist in the first place, or your reasons for the concern.

You seem to want to invent drama for something that is really simple and
which was described a few times already.

Let's take an example, just so that you can better understand without
having to deal with the accusative tone of all of your posts.

Let's say I have screenshotted two letters I sent to my boss telling her
that she's an idiot. Let's say my name and address are embedded in the
middle of that letter. Let's say I don't want my name and address to be
posted, but I want the rest of the two letters posted.

What do I do?

Easy right?
I just cut some stuff out and I cover other stuff up.

This is sort of what I was showing in the Trump and Hillary screenshots
where the Hillary screenshot covered some of the Trump screenshot and where
I had placed black blocks over some of the text in the Hillary screenshot.

Both things are what Paint.NET puts in "layers".
1. Covering something with something else, and
2. Cutting out something

I just don't want any of the covered up or cut out detail to be in the
final image.

If I started with a JPEG with full EXIF, you and I both know that the
thumbnail STILL has all the original information, so that would be stupid
to use JPG with full EXIF (unless I re-created the thumbnail).

Surely with all your made up drama, you must know this. If not, see
https://security.stackexchange.com/q...ed-in-an-image

And also see this:
https://photographylife.com/how-to-delete-exif-data/

Anyway, I just don't want the same information leak of layers in my output.

It's really a very basic and simple drama-free question that doesn't
warrant the cloak-and-dagger innuendo of all your posts.

"Savageduck" wrote

| Editing photo files in BMP (or any other bitmap format)
| is not a particularly good idea, and it is probably the
| last format I would choose.

Not a "good idea"? I don't know any clearer way to
explain this. A BMP is a basic bitmap. All the non-RAW
file formats we're talking about are nothing more than
containers for bitmaps. A BMP is just the simplest
container. The others add compression and/or extra
functions. But *they are all simply containers for a
bitmap*.

| the nondestructive edits/adjustments are either
| saved in a lossless file format, usually TIFF...

Which is basically a ZIPped BMP. It's the same as
a BMP (or PPM, if I've read the specs correctly), just
compressed to take less space. When you re-open
that file you have a bitmap. when you work on it you
work on a bitmap. When you resave as TIF you're saving
a bitmap in a ZIP package. (Or some similar compression
method.) TIF is fine, if you want to save space, but
that's the only difference.

On Wed, 7 Jun 2017 19:48:07 -0400, Mayayana
wrote:

https://s3.postimg.org/ajmpdg7zn/exif.gif
Interesting. For some reason they think they're
allowed to be sleazy because the format accepts
metadata.

I thank you for pointing out that I should look for something that
Paint.NET put into the meta data that pinpoints not only the software used
but also the specific version.

It's easily enough removed, but I didn't know it was there until you said
to look for it.

| I tried uploading the original PDN and it won't even upload to the
| postimage.org web site. So I have to save the PDN as something else.
|
Yes. It's a custom Paint.Net format. Even if
you could upload it, most people wouldn't be able
to view it.

Luckily it seems that a flatten command is required to save to GIF or JPG
or PNG, so, I assume the Paint.NET layers are removed at that time.

That was really the question in the first place, which was how to tell if
the layers are definitely removed.

Bingo. (Assuming you meant to type PNG there and not PDN.)

Yes. PNG.

In article , Mayayana
wrote:


| As far as folks "using tools like Photoshop would know enough not to use
| JPEG", and "know enough not to work in JPG, which is essentially a Web
| format." You are making another bunch of assumptions based on your
mindset.
| While for many shooting and editing RAW is a prefered workflow, (I shoot
| RAW+JPEG) there are other photographers, including pros who shoot
RAW+JPEG,
| and JPEG only, and the resulting JPEG files are used well beyond being
| isolated as "essentially a Web format."
|
I understand that photos are often taken as
JPGs. But *working* in JPG, a lossy format, is
another matter. It doesn't make sense not to
save to a lossless format before editing.

it doesn't matter with a non-destructive workflow

The
format is only in use in cameras in the first
place because it's royalty free, supports a
wide range of compression, and is the only
fully supported, 24-bit image for browsers and
cross-platform.

no, that's not why.

(PNG is pretty much supported
now, but it didn't used to be, and compression
is not great.)

That last point is the most critical. Most people
taking photos don't much care about quality.
They do care about how many photos they can
fit on their card and they care about being able to
send those photos to others. As they say in NY,
they don't know from formats. JPGs became
default *because* it was a universally supported
Web format.

jpeg predates the web.

jpeg became the default on the web because it was already commonly used
everywhere else before that.

If size and compatibility were not an issue, some
kind of basic bitmap would be the most sensible
way to store non-RAW images. That has nothing
to do with my "assumptions". It has to do with
how digital images are stored.

definitely wrong.

PPM (P6 type) seems to be basically the same
idea as 24-bit BMP. I wouldn't call either proprietary
format. They're just a record of pixel values in
a bitmap with a small header to tell you what
you're dealing with. That's the point of working
with such a format. Your editor has to convert
to a bitmap anyway, and a bitmap is not lossy.
So if you have the space there's no reason not
to store images as bitmaps.

there is.

In article , Mayayana
wrote:


| I first encountered BMP back in the late 80's and instantly knew it was
| a dead format due to its over simplistic memory hungry design at the
| time. I'm surprised it's even mentioned anymore.
|

I'm guessing Alan Browne is also a Mac user.
The ignorance of how these things actually work
among Mac users is striking.

the ignorance is not where you think it is.

| BMP is just a simple raster format and there are several editors that
| can accommodate those...
|
Exactly. Not just a simple raster format. *The*
raster format. Aside from the "magic" bytes,
width/height data, orientation, color depth,
etc, a 24-bit BMP is simply the byte values that
represent the pixels in the image. It's what gets
loaded into memory in Photoshop or any other
editor, regardless of what file format one starts
with. The header holds only enough info to know
how to read the bytes. The Mac PPM format
seems to be essentially the same. It would be
nonsensical not to have a basic bitmap format
option.

the option exists, however, it's not used because so many better
options exist.

To say that's outdated is like someone saying
that car motors are outdated because they don't
understand that that's how a car moves.

car motors are indeed outdated.

electric vehicles are the future.

In article , Ken Hart
wrote:

I wouldn't
expect the average Mac user (or Windows user, for
that matter) to know file types, but I would have
thought that people using tools like Photoshop would
know enough not to work in JPG, which is essentially
a Web format.

nonsense. jpeg predates the web by roughly a decade.

The Joint Photographic Experts Group was organized in 1986, and issued
the first JPEG standard in 1992.

ARPANET adopted TCP/IP on January 1, 1983. On August 6, 1991, Tim
Berners-Lee posted a summary of the hypertext project. Internet Service
providers began appearing in the late 1980's. In 1995, NSFNet was
decommissioned, removing the last restrictions on commercial traffic on
the internet.

A decade is ten years. The JPEG _group_ was three years after TCP/IP,
five years prior to HTML, and nine years prior to the commercial
internet. The JPEG _standard_ was adopted nine years after TCP/IP, one
year after HTML, and three years prior to the commercial internet.

i said the web, not tcp/ip. do try to keep up.

1994-1995 for the two popular early browsers:
https://en.wikipedia.org/wiki/Netscape_Navigator
https://en.wikipedia.org/wiki/Internet_Explorer_version_history

the very beginning of the web goes back further, however, almost nobody
heard of it until netscape & ie.

it was also designed on a next cube running nextstep, from which mac os
is derived.

http://webfoundation.org/about/vision/history-of-the-web/
Tim also wrote the first web page editor/browser (³WorldWideWeb.app²)
and the first web server (³httpd³). By the end of 1990, the first web
page was served on the open internet, and in 1991, people outside of
CERN were invited to join this new web community.
....
Tim moved from CERN to the Massachusetts Institute of Technology in
1994 to found the World Wide Web Consortium (W3C), an international
community devoted to developing open web standards. He remains the
Director of W3C to this day.

https://en.wikipedia.org/wiki/Mosaic_(web_browser)
Mosaic was developed at the National Center for Supercomputing
Applications (NCSA)[5] at the University of Illinois Urbana-Champaign
beginning in late 1992. NCSA released the browser in 1993,[7] and
officially discontinued development and support on January 7,
1997.[8] However, it can still be downloaded from NCSA.[9]

In article , Chaya Eve
wrote:

That seems like a great plan since NONE of them have the layers I was
worried about!

I still don¢t quite understand your concern over layers which shouldn¢t
exist in the first place, or your reasons for the concern.

You seem to want to invent drama for something that is really simple and
which was described a few times already.

Let's take an example, just so that you can better understand without
having to deal with the accusative tone of all of your posts.

Let's say I have screenshotted two letters I sent to my boss telling her
that she's an idiot. Let's say my name and address are embedded in the
middle of that letter. Let's say I don't want my name and address to be
posted, but I want the rest of the two letters posted.

What do I do?

quit your job before you get fired, because your boss already knows who
the idiot is.

Easy right?
I just cut some stuff out and I cover other stuff up.

yep. very easy.

as always, you make the simplest things into a huge ****ing ordeal.




Anyway, I just don't want the same information leak of layers in my output.

it has already been explained to you how to remove what you don't want.

for some bizarre reason, you continue to ignore the answers.

In article , Mayayana
wrote:


| Editing photo files in BMP (or any other bitmap format)
| is not a particularly good idea, and it is probably the
| last format I would choose.

Not a "good idea"? I don't know any clearer way to
explain this.

that's because there isn't any.

A BMP is a basic bitmap. All the non-RAW
file formats we're talking about are nothing more than
containers for bitmaps. A BMP is just the simplest
container. The others add compression and/or extra
functions. But *they are all simply containers for a
bitmap*.

you're confusing file format with data in memory.

you're also ignoring a non-destructive workflow.

On Jun 7, 2017, Chaya Eve wrote
(in article ):

On Wed, 07 Jun 2017 17:52:14 -0700, Savageduck
wrote:

That seems like a great plan since NONE of them have the layers I was
worried about!

I still don¢t quite understand your concern over layers which shouldn¢t
exist in the first place, or your reasons for the concern.

You seem to want to invent drama

Nope!

for something that is really simple and
which was described a few times already.

It is quite simple. However, you have added complications which shouldn’t
exist in screenshots, and should be irrelevant in edits of screenshots.

Let's take an example, just so that you can better understand without
having to deal with the accusative tone of all of your posts.

Wait until I get out my rubber hose.

Let's say I have screenshotted two letters I sent to my boss telling her
that she's an idiot. Let's say my name and address are embedded in the
middle of that letter. Let's say I don't want my name and address to be
posted, but I want the rest of the two letters posted.

What do I do?

Easy right?
I just cut some stuff out and I cover other stuff up.

If only you kept things that simple.

This is sort of what I was showing in the Trump and Hillary screenshots
where the Hillary screenshot covered some of the Trump screenshot and where
I had placed black blocks over some of the text in the Hillary screenshot.

Aah! A political humorist.

Both things are what Paint.NET puts in "layers".
1. Covering something with something else, and
2. Cutting out something

That much I understand.

I just don't want any of the covered up or cut out detail to be in the
final image.

Do you want to edit the image or not?
That last statement seems to indicate that you don’t want the edits to be
in your final image, or is it edit details contained in the Metadata which
concern you. If Paint has the edits in layers flatten it and strip, or edit
the metadata.

If I started with a JPEG with full EXIF, you and I both know that the
thumbnail STILL has all the original information, so that would be stupid
to use JPG with full EXIF (unless I re-created the thumbnail).

Then strip, or edit the EXIF data, using your tool of choice.

Surely with all your made up drama, you must know this.

No drama on my part, you are the one wanting to obscure information.

If not, see
https://security.stackexchange.com/q...of-thumbnails-
or-just-a-previous-thumbnail-is-embedded-in-an-image

That article seems to be a very Windows related problem.

And also see this:
https://photographylife.com/how-to-delete-exif-data/

All information anybody who has used Lightroom, Photoshop, or any good
photo-editor should be aware of, I certainly have been for many years.

Anyway, I just don't want the same information leak of layers in my output.

The solution has been stated repeatedly; flatten the image, and strip the
metadata.

It's really a very basic and simple drama-free question that doesn't
warrant the cloak-and-dagger innuendo of all your posts.

No cloak-and-dagger innuendo, it just seems to me that you are creating a
complicated exercise from what should be quite simple.

--

Regards,
Savageduck

In article .com,
Savageduck wrote:

Anyway, I just don't want the same information leak of layers in my output.

The solution has been stated repeatedly; flatten the image, and strip the
metadata.

yep.

It's really a very basic and simple drama-free question that doesn't
warrant the cloak-and-dagger innuendo of all your posts.

No cloak-and-dagger innuendo, it just seems to me that you are creating a
complicated exercise from what should be quite simple.

it's what he does.