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on how to know what you are doing

Jun 13, 2014, 09:05 (This post was last modified: Jun 13, 2014 09:08 by Sagemode.)
Post: #1
on how to know what you are doing
Graphic work or graphic image manipulation is probably the most frustrating experience for me to date.

I believe large part of that is due to my colour-blindness.

I am not capable of identifying identical hues when they have different levels of saturation and brightness (value).

Meaning, when two colours look identical in other respects (for example greens and yellows, greens and oranges, blues and purples, greens and browns, greens and grays, etc.) I am usually not able to differentiate or identify properly.

I also may not be able to notice the lack of saturation when I think something is a green. A cold green and a gray are often the same to me on first sight.

I usually require large surfaces of a colour in order to properly evaluate it. A single pixel, basically, is impossible for me to recognize.

I think that when I convert something to grayscale it will be a breeze but real colour photos depend on saturation (sometimes you only have to work with one hue) and although brightness levels are easy to me, I could never convert it back to full-colour.

Basically when I'm photo editing I don't have a clue as to what I'm doing. I just try and try and try and I'm pretty much just randomly changing things in the hopes of improving it. I can evaluate the result in terms of harmony and quality but I don't know what needs to be changed in order to get there.

In short, I work without understanding. And it's frustrating as hell.

And I can't just commission other people to do every minor photo or image work for me.

Right now I'm trying to edit a real photo of some remote control for some audio device. I need to visually change some of the buttons. I need to transplant one icon, and invent/create a new one. But the picture is very noisy, grainy, and the modifications I make need to have an equal level of noise. If they don't, everyone will sense the oddness of the picture and mistake that for the oddness of my logical changes in terms of control design.

So it has to look natural and although I have succeeded in some button displacement I can't get the icons right.

One icon is a filled circle. It gets the same colour from an icon near to it but the edge in particular (there are contrast patterns where two colours meet) needs to look natural. I might be able to produce an adequate contrast style but then it still needs the proper noise.

The other icon is getting displaced from the top of the picture (with higher brightness and slighly different saturation) to a lower part where it has to blend in next to an icon that belongs there.

That second job is difficult because I can't just turn the exterior to fully transparent (the contast pattern depends on the brightness of the exterior) and even if I find the perfect pixel to color-to-alpha the entire transplanted-icon-layer it will look extremely weird. For starters, the noise will be off.

What techniques can I use for this without needing to be able to identify colours myself?

In other words, I require a technique that is just mathematical and that GIMP can do for me.

It seems most of my problems in this case involve lack of noise and I must admit I haven't looked into noise generation too well but I'm not at the computer right now so I'll ask anyway.

And I don't want to post any picture because I really need a macro view right now because any micro work I do will only leave me more frustrated because I made some wrong choices earlier on.

I really need to use the right approach and not depend on my own visual perception. I could never ever do this pixel-by-pixel. Unless it was a grayscale, then it'd probably be easy.

More generally, I am trying to understand the mistakes I am repeatedly making that result in all this frustration. In the past I have tried theme-designing or modification (for webpages) and I did fine as long as it didn't involve colour-schemes Sad.

I tried using a colorscheme generator to suggest new colours but it was inadequate.

Perhaps I just need to study the mathematics behind colour manipulation? Back in the day in MS-DOS I wrote my own palette-chooser but it was just a nice selection tool based on RGB. If I can learn how RBG relates to HSV perhaps I can get somewhere.

It's like trying to learn music when you're deaf Undecided.

My palette-chooser was just an application with three sliders and panes for each primary, each secondary and the final tertiary combined result. So you would see the prime red, green and blue, their overlaps (yellow, violet, cyan) and the end colour which would be the one you wanted.

And now I know the mistake I've made. I need to use my own tools for selecting colours, tools I like working with and that make sense to me!!

Tools that have large surfaces and that show combined colours. In MS-DOS there WAS no default colour-picking tool so I had to create my own. And I did a lot of playing around with the basic RGB math of it too. I need to pick that up.

Wow! My tool!! I shall dredge it up from the catacombs of my programming archives, find a copy of Qbasic.exe, boot up my DOSbox environment and I will be a happy camper Big Grin.

My god, the mistakes you can make.. and never knowing what they are. This is going to feel SO good. Away with the frustration. I am just going to completely redo this image edit and see what I end up with. It may take a while to input every colour I need into it, but it's enough.

Wish me prosperity and Godspeed Big Grin.
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Jun 13, 2014, 09:45 (This post was last modified: Jun 13, 2014 09:53 by rich2005.)
Post: #2
RE: on how to know what you are doing
Perhaps look at using some of the Gimp dialogs and keep them detached from the main gimp window.
Some of the palettes have named colours, and in the palette editor dialog the name is shown at the bottom along with the RGB values.

You can also use the FG/BG color dialog to pick any of these colors and they do show as corresponding RGB/HSV values.

[Image: HsotRg3.jpg]

edit: nothing to stop you adding your own names to a Gimp .gpl palette file - it is text
the first entries in the Named Colors palette

GIMP Palette
Name: Named Colors
Columns: 16
#
255 250 250 snow (255 250 250)
248 248 255 ghost white (248 248 255)
245 245 245 white smoke (245 245 245)
220 220 220 gainsboro (220 220 220)
255 250 240 floral white (255 250 240)
253 245 230 old lace (253 245 230)
250 240 230 linen (250 240 230)
250 235 215 antique white (250 235 215)
255 239 213 papaya whip (255 239 213)

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Jun 13, 2014, 10:31
Post: #3
RE: on how to know what you are doing
Two remarks:

Never overlook the Sample points and Pointer dialogs.

Professionals work from near-perfect pictures (taken with a DSLR, good lighting, special background...). That makes it easy for them. Beginners usually work on crap pictures (smartphone, or badly compressed Jpegs from the web), so they add these difficulties (noise, blurriness and else) to the difficulties that even the pro has to tackle. But of course they have the same expectations as the pro as to the final result. Disappointment ensues.

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Jun 13, 2014, 15:10
Post: #4
RE: on how to know what you are doing
Thanks. I'm getting some real support here, not silly remarks Smile.

The FG/BG dialog is pretty useless to me because its surface is way too small for me.

Also, I can't have any HSV information, those numbers do not mean anything to me, although I have tried manipulating them many times.

I love the sample point functionality although I don't know any real use for it yet, but that'll come probably.

The Pointer dialog is pretty useless to me, I will just use the color picker and shift-click instead. Much better for me. But even its surface is way too small for me to be able to 'perceive the color'.

I have found my program. I have its source and executable. Turns out I wrote it as a shareware version and now my own nag screen is nagging me lol. I have yet to discover how to "register" it lololol. Relearning Qbasic as I go. Just located my copy of Qbasic.exe and its help file. I wrote it when I was 14. Never knew I was that good lol, I fail to understand those language constructs now. It even has a drop-down menu with some functionality although most seems to be not implemented. And I'll need to change the decimal output to hex. That's it, probably. Being a DOS program copy&paste is going to be tough. I'm also not sure if the keyboard reading works properly in my emulator. But it seems to be everything I need.

Quote:Professionals work from near-perfect pictures (taken with a DSLR, good lighting, special background...). That makes it easy for them. Beginners usually work on crap pictures (smartphone, or badly compressed Jpegs from the web), so they add these difficulties (noise, blurriness and else) to the difficulties that even the pro has to tackle. But of course they have the same expectations as the pro as to the final result. Disappointment ensues.

Ouch, good point. Tough point too. The image I used appears to be the best one available on the web. It is a stock image of 968x1500 but it's a JPEG. I'm not sure if it would have mattered much if it was a PNG? I own the unit myself but I can never get anything near the quality of a professional stock image, I'm no photographer.

It is a picture of a remote control for the Squeezebox Boom network radio.

Perhaps I could ask the folks at Logitech or over at the SlimDevices forum whether anyone has a stock image of better quality. But will it make a lot of difference? I should be able to do it anyway.

Playing around with adding a little RGB noise and then a little Gaussian Blur already improves my artifact though. Not enough yet though.

I know I expect a perfect result but I should be able to do it with my RGB tool.

And my picture is a reasonable quality stock image anyway, so.... I don't think I'm trying to do the impossible here.
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Jun 14, 2014, 04:58
Post: #5
RE: on how to know what you are doing
My tool is way too limited...

It turns out QBASIC supported only 4 million colours, which is about 64x64x64, instead of 256x256x256.

And the interface becomes unworkable if I expand it to full-colour.

Moreover, that language is so limited it doesn't even support arrays in user defined types (structs/records).

It was a very convenient scripting language for doing graphics output though, I mean displaying lines and surfaces and just designing simple controls without much ado.

The language even lacks functions like Min and Max. And I never liked the full QuickBasic IDE/interpreter/compiler package.

It would seem the most suitable form for something would be a GIMP extension/plugin/addon.

I had a chat with a dev from the IRC and it seems Python is an excellent language of choice for it. There is an excellent python wrapper for the C library of libgimp.
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Jun 14, 2014, 08:58
Post: #6
RE: on how to know what you are doing
(Jun 14, 2014 04:58)Sagemode Wrote:  My tool is way too limited...

It turns out QBASIC supported only 4 million colours, which is about 64x64x64, instead of 256x256x256.

And the interface becomes unworkable if I expand it to full-colour.
Colors are just triplets of bytes (i.e. values 0-255). All languages support that. The colors they can display using their display API is a different problem (and can be stuck with 80-era hardware...)

(Jun 14, 2014 04:58)Sagemode Wrote:  Moreover, that language is so limited it doesn't even support arrays in user defined types (structs/records).

It was a very convenient scripting language for doing graphics output though, I mean displaying lines and surfaces and just designing simple controls without much ado.

The language even lacks functions like Min and Max. And I never liked the full QuickBasic IDE/interpreter/compiler package.

I have never seen anything with "Basic" in its name looking like a real programing language (except perhaps the original Dartmouth Basic)

(Jun 14, 2014 04:58)Sagemode Wrote:  It would seem the most suitable form for something would be a GIMP extension/plugin/addon.

I had a chat with a dev from the IRC and it seems Python is an excellent language of choice for it. There is an excellent python wrapper for the C library of libgimp.

Not really news for anyone here. However, be reasonable in your expectations: this stuff is very powerful to string together existing Gimp operations, but:
  • pixel-peeping in Python is going to be slow (remember that you are going to handle several million pixels..). If you really need to do that, you have better use C than Python.
  • With Python or C, you cannot do on-canvas user UIs (this is the realm of the built-in Tools, not of plugins).
In practice, most people who think they need this kind of functionality are over looking existing capabilities.

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Jun 14, 2014, 11:21
Post: #7
RE: on how to know what you are doing
Quote:... Relearning Qbasic as I go. Just located my copy of Qbasic.exe and its help file. I wrote it when I was 14..

Ah nostalgia...

Still have my Quickbasic disks, (rather than the interpreted Qbasic) and printed manuals.

[Image: 4LaR0sy.jpg]

Going back from then to the middle 80's and my Sinclair QL. A somewhat eccentric built in BASIC. It did not matter much if you were colour blind. If you were fortunate enough to own a (very expensive) colour monitor you might get a 4 colour display. otherwise green on black was normal Wink

[Image: kKTcyc0.jpg]

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Jun 17, 2014, 10:14
Post: #8
RE: on how to know what you are doing
Hey, I'm sorry if I gave off the wrong impression.

I know perfectly what I'm doing. I'm using a stock image of good quality. There's no need for me to feel humbled or humiliated because I failed to see something, supposedly. The thing I intend to do is perfectly reasonable and I just need a self-designed tool to do it. One could argue that all tools are self-designed, but I'm pretty sure there is no tool that honours my particular self. So I will just go ahead and make this thing. I'm already busy with it and it's going along nicely.

Using Python and PyGTK, as indicated. No need for me to feel insecure about that.

Thanks. I was feeling a bit 'daunted' these last days because I initially thought the remark by "ofnuts" was warranted. But it was not. I'm not being mistaken about what I want and whether it is possible. What I want is perfectly reasonable.

Going to fix the other stuff I have said to other people that was a bit stupid ;-).

Ah, this feels much better again. This project will go along fine. I'll let you know what I end up with.

Regards, Sage.
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