Search found 1945 matches
- 2014-06-08T10:41:28-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Side note: It is my current opinion that the sharpest Keys cubic that's usable for general natural image EWA upsampling is the Robidoux one. IMO, it's actually a nudge too sharp. Consequently, I don't recommend EWA Mitchell, RobidouxSharp, and Catmull-Rom for upsampling. And I actually don't really ...
- 2014-06-08T10:09:31-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
I persists in thinking that if you vary B and C (without, possibly, sticking to Keys cubics) you'll find a combination that compares. The only thing that could make a comparable result reachable with 4x is that you extend your disc up to radius 2.5. The problem with this is: the second function fro...
- 2014-06-08T09:55:56-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
If any reader has any comment regarding the look of the RobidouxSoft result, I'd like to read it.
Also, if Sergio could post the result with EWA Robidoux, I'd be thankful.
Also, if Sergio could post the result with EWA Robidoux, I'd be thankful.
- 2014-06-08T09:50:27-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Sergio: I wish I could tell you what B,C combination would give you something that complies to the look that I guess you are after. However, this look appears to be fairly far from what I have been trying to achieve, and consequently it is likely to be far from Keys cubics. I actually like the resul...
- 2014-06-08T09:16:02-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
I persists in thinking that if you vary B and C (without, possibly, sticking to Keys cubics) you'll find a combination that compares.
The only thing that could make a comparable result reachable (correction: UNreachable) with 4x is that you extend your disc up to radius 2.5.
The only thing that could make a comparable result reachable (correction: UNreachable) with 4x is that you extend your disc up to radius 2.5.
- 2014-06-08T08:53:33-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Don't give up too fast.
Let's first try Keys cubics: Once you choose B, set C=(1-B)/2.
Start with Mitchell which is the Keys with B = 1/3.
Then, vary B until you're happy with what you get.
Let's first try Keys cubics: Once you choose B, set C=(1-B)/2.
Start with Mitchell which is the Keys with B = 1/3.
Then, vary B until you're happy with what you get.
- 2014-06-08T08:34:51-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
EWA Catmull-Rom is super jaggy. Some people have liked it for downsampling but I've never liked it, up or down.
Try EWA RobidouxSoft:
Try EWA RobidouxSoft:
Code: Select all
B = (9-3*sqrt(2))/7 = 0.67962275898295921
C = (1-B)/2 = 0.1601886205085204
- 2014-06-08T08:04:57-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
A question for you: that jinc2 filter I made, technically, should I call it ewa-lanczos2sharp? It's not really what I call EWA Lanczos2Sharp because it does not use Jinc and it does not use one of my standard deblurs. It's a deblurred EWA Sinc-windowed Sinc 2-lobe. <- Too long for a short name. So ...
- 2014-06-08T08:00:58-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Sounds like you're running out of "registers". "Red-black" tricks (this includes my initial suggestion about min and max being computed as min(min(.,.),min(.,.)) instead of min(.,min(.,min(.,.))) ) generally use more memory. If it's not too much to ask, could you try kolor = mul(...
- 2014-06-08T04:10:48-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
One last "manic perfectionist" thing: Some of the positions, you know ahead of time that they are within 1, or farther than 1. So, you could use a special weight function for these special cases and skip some branches for these "indexes". What I mean is this: I assume that you f...
- 2014-06-08T00:52:10-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Standard polynomial evaluation trick: Horner's rule.Hyllian wrote:It saved me like 20% of processing time! Indeed it works! Thanks.
- 2014-06-07T13:53:22-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
You write beautifully clear code.
- 2014-06-07T13:52:27-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
One last "manic perfectionist" thing: Some of the positions, you know ahead of time that they are within 1, or farther than 1. So, you could use a special weight function for these special cases and skip some branches for these "indexes".
- 2014-06-07T13:44:55-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
If you have set things up so that the alignment is the same throughout the computation, a number of the 16 texels are outside of the discs and consequently always have coefficient 0, which means they can be dropped. (Maybe this requires reflections of the data to put it in "standard position&qu...
- 2014-06-07T13:38:15-07:00
- Forum: Users
- Topic: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
- Replies: 134
- Views: 199906
Re: Sigmoidized Ginseng (pronounced "Jinc-Sinc") resampling
Suggestion: Compute the weights using the formulas used in ImageMagick's resize.c if (x < 1.0) return(resize_filter->coefficient[0]+x*(x*(resize_filter->coefficient[1]+x*resize_filter->coefficient[2]))); if (x < 2.0) return(resize_filter->coefficient[3]+x*(resize_filter->coefficient[4]+x*(resize_fil...