Mentor request for gif redraw

[Steel General]

After a quick bit of Google-Fu I found this regarding Firefox and animated images. Looks like it supports .APNG (which I had never heard of).

[icosahedron]

Wow. Great response, thanks guys.
I think if we do it here it might help another noob in the future.

I'm getting to grips with some of the Gimp functions - my copy has a gif converter, so that should take care of colour conversions, and this image has only very basic colours anyway.

Image->Mode->RGB. That's what I needed to start with, thanks. (I think. I'll check it out later). Once I can access the colour tools, I'll probably muddle through, though to save me some time and experimentation, my next question will be:

Is it possible to change a range of colours (eg several shades of blue into several shades of red) simultaneously, or will I need to pick out and convert each shade individually? I did manage to adjust the colour selector slider to pick out all the blues in one go, but since I couldn't access the colour changing tools I couldn't experiment with changing them to a similar range of reds.

Here's a link to the little gif I'm playing with.

http://i22.photobucket.com/albums/b3...ndrewsflag.gif

Maybe it's one of yours? Just look on this as sincerest flattery.

Gimp gives me access to the individual frames of the sequence, and I want to play with changing the colours to get a feel for how the flag is painted. Eventually, when I've figured out exactly how it's done, I want to use this image as a model to create my own copright-free flag-waving smiley and produce it with a range of different flags.

The smiley is simple, even I can draw one of those from scratch, but that fluttering flag is not so easy. I'm thinking that if I want to produce a range of these, the best thing would be to create the fluttering and shadowplay separately (is that what's called a mask?) and see if I can use flat colours for the different flag designs. I think that's going a step beyond the original and might be beyond my skills, but if you don't try...
I couldn't do gifs at all until last week.

[Redrobes]

I did a fluttering flag once and its not all that hard to do but you need to do that in a 3D program like blender (or something simpler). In that case you just texture map the flat flag onto the flag and make the geometry in the flag ripple. Then render all the frames out. Its then no problem to substitute the flag and do again and again.

You could do the substitution onto the gif anim by hand I guess but I think thats a lot of work if doing more than one.

In PSP there is a dialog widget thing where you tell it a range of color shades to translate to another set. In image magick you can do same with a color lookup table. Don't know about gimp tho.

Edit - I still have it...

[töff]

I had a Gif util once that would let you adjust the color table as a whole, in much the way that you can adjust HSB or RGB images. I'm sure some Gif utils still have such a thing.

[RobA]

In PSP there is a dialog widget thing where you tell it a range of color shades to translate to another set. In image magick you can do same with a color lookup table. Don't know about gimp tho.

In Gimp it is he colour map rotate. But it only works on RGB images Alternately, you can jsut select the flag area and just use the hue slider in the HSV adjustment dialog *picking the last used setting from the preset drop menu) on each layer, then convert back to indexed.

Here is an example of that workflow on your flag:
http://www.majhost.com/gallery/ffaat...re/redflag.gif

-Rob A>

[icosahedron]

Sorry, I answered my own question before logging on again. Yes, I found you can change all the shades of blue by moving the slider on Hue.

3D programs are something I really don't have time to learn. Learning gif animation is bad enough.

Ok, here's what I've made. Note this is a 1st attempt WIP.

I drew a smiley with a rectangular flag from scratch, so this one is all my own work, then I copied the layer, selected the flag and ran Filters->Distorts->Curve Bend. I then followed it with a few strokes of Burn.

This repeated 7 times with different curves, for an 8 frame gif.

The resulting gif is shown here.

However, I seem to have hit a problem. Despite copying the original layer each time (with the rectangular flag, not copying the last distorted copy), the distort seems to carry forward from one copy to the next, making the flag more and more of a mess in successive frames, and I can't figure how to erase pixels to transparent in order to touch in the messy bits.

When I choose eraser and click on pixels, nothing happens, though I can use pencil and alter pixel colours to anything other than transparent.

So...

Why can't I erase pixels?
Why does the distort carry over to successive frames, and how do I prevent it?
Is there a way to do the curve distort on the horizontal axis as well as vertical?
Any feedback on the WIP greatly appreciated

Thanks.

[RobA]

Change your Frame Disposal (in the gif file save dialog) to "One Frame per Layer (Replace)"

-Rob A>

[Notsonoble]

Konqueror is supposed to support mngs, but it doesn't seem to be working in the windows KDE4 port... I'll try the 'nix box really quick.

Edit: yeah no luck there either.

[icosahedron]

Change your Frame Disposal (in the gif file save dialog) to "One Frame per Layer (Replace)"

-Rob A>

Doh! Yes, if it's seeing through all layers that'll explain the mess and the inability to erase - I'd have to erase each pixel 8 times to drill down to transparent.

Thanks Rob, I missed that prompt, otherwise I would have used it.

I think Redrobes' 3D version is the only one that would allow an instant flag change. I can't see any way in Gimp to replace the flag pattern without completely recreating the gif. (other than recolouring similar patterns) However, I've got it down to about 2 mins per layer now, so I can build up a new flag in around a quarter hour, (excluding pattern creation) which isn't too bad if I only need a couple. I wouldn't want to do a 'flags of the world' range that way, though.

Ok, here's the re-saved version, let's see what this turns out like.

Edit: Hmm, there's still a problem on the top edge, though the bottom edge seems to be sorted now. I wonder if the flag's too close to the top of the bitmap? Or maybe the selection area for the distort didn't completely enclose the flag border?
<Groan> sounds like another redraw...

[icosahedron]

Right, here goes, I've redrawn it (again) moving the flag down a little and selecting an overlarge area for the flag, and I've also taken the trouble to map out the sine wave flow, (sequential directions on the curve bend) so the ripples should be smoother.

Edit: Nope, there's still a problem - notably on the bottom edge again now. I really dunno what I'm doing wrong. I did the 'Replace' thing, but it looks like it's still seeing more than one layer at a time. Unfortunately, I can't play it clearly anywhere other than here. It doesn't show up clearly on Gimp's replay. At least the ripple is smoothed out now. I'll poke about with it some more.