Writing images of a specific size?

Hi,
Fraqtive is a great fractal generator! I love it!

I recently upgraded to 0.4.4 and I don't see feature that used to exist in a previous version
(I don't remember which version..)
The earlier version had a place where you could specify the size of the output image.
Does this feature still exist?
I used it to generate a full sized desktop background, and now it appears that you can only
write out an image the size of the viewing window.

I really like all the new capabilities you've added!
If this feature slipped away somehow... I'd like to request it again..

Thanks for a great program!
-chuck

Re: Writing images of a specific size?

I was wondering this myself.

I did find a way around this. Go into full screen mode and then use ctrl+s to initiate a save. This will generate a full sized save based on your screen resolution.

Having the ability to save the fractals in a different resolution would be helpful.

Re: Writing images of a specific size?

Yes, this feature was present in previous versions (0.2.x and 0.3.x) and I'm planning to re-add it one day to version 0.4.x (see the roadmap). I can't tell exactly when because right now I'm more involved in WebIssues, but I'd say next year.

Also it's a very good workaround to save images in full screen mode; I've been using it as well.

Regards,
Michał

Re: Writing images of a specific size?

Great tip!
That does the job...

Thanks
-chuck

Re: Writing images of a specific size?

I just got wise to that too. I was loading into Photofiltre and resizing the image. Not the same aspect ratio. To nearly square. I just hit the print screen key. Didn't think of Control-S :)
--
"How come we don't know the I.Q. of the guy who invented the test?"

Re: Writing images of a specific size?

That should be mentioned in the tutorial. I'll fix it in the next version (and I'll also add the possibility to generate images of arbitrary size) which will be released in a few months.

Regards,
Michał

Re: Writing images of a specific size?

Hi,

is there a way to specify a really high resolution? In the moment, the maximum seems to be 4000 pixel. I would need something like 30000 pixel for a high-resolution poster.

Cheers

olebole

Re: Writing images of a specific size?

That's correct, the maximum size is 4000 pixel. Greater images could easily take a few gigs of memory, so the process would have to be redesigned to calculate only a part at a time. I'm so busy with my other projects at the moment, that I can't really tell if and when I will be able to return to Fraqtive.

Regards,
Michał

Re: Writing images of a specific size?

Hey, I just changed the limits in the code, and I can easily generage 20,000 x 20,000 images.

As far as I can see, there is no reason to put such a small limit (4000) on the dimensions. At 20,000 by 20,000, I only needed about 1.6GB of memory.

I tried a 40,000 x 40,000 and it failed in creating a QImage because apparently QT images have a 4GB limit (i.e. they are limited to 32 bits I guess.). Hopefully this limit will go away in more recent version of QT.

40,000 px x 40,000 px * 4 bytes/px / 1024/1024/1024 = 5.6GB. <--- fail
20,000 px x 20,000 px * 4 bytes/px / 1024/1024/1024 = 1.5GB. <--- okay

-Caleb
Shoot, for some reason my code patch is causing this post to be caught by the spam filter. To fix it, simply go into the source and modify src/generateimagedialog.ui and change '4000' to '100000' or whatever you like., then recompile.

[EDIT: I just found the relavent limitation, and it's that the max Qimage dimension is 32767, so the limits should be 32767 x 32767, rather than 4000, 4000: http://stackoverflow.com/questions/7080052/qimage-qpixmap-size-limitations]

Re: Writing images of a specific size?

Thanks for the info. Just keep in mind that this will only work in the 64-bit version of the program. Also, in addition to the 1.5GB for the bitmap, another 3GB is needed for the temporary buffer.

Regards,
Michał

Re: Writing images of a specific size?

Ah, interesting. I didn't see the 3GB spike when I was watching the memory usage. In any case, it's not a problem on a modern 64-bit computer with 8 GB of ram. It only takes a few minutes to compute on my 4 year old Macbook pro with a core-2 duo at 2GHZ with 8GB ram and I can get fantastic high resolution images.

-Caleb