Google| Subject | Re: Lenses and sharpening |
| From | Sandman |
| Date | 09/22/2014 09:17 (09/22/2014 09:17) |
| Message-ID | <slrnm1vjpj.3ss.mr@irc.sandman.net> |
| Client | |
| Newsgroups | rec.photo.digital |
| Follows | Eric Stevens |
| Followups | Eric Stevens (2h & 37m) > Sandman |
In article <f1ju1ad55jnmcbf58u8t8jvttl94othufv@4ax.com>, Eric Stevens wrote:
Yes, they are.Eric StevensSandmanSandman
1. HPS is, in the example, a pixel-altering process. 2. JPG compression is a pixel-altering process 3. Gaussian blur is a pixel-altering process.3 can *NOT* reverse 1 with 2 in the middle. It is impossible. It can *counteract* it and the end result may be satisfactory, but number 1 has *NOT* been reversed. Pixels have been altered in the interrim that 3 can not take into account.Eric Stevens
You haven't understood my diagram above. Once I would have tried to explain it to you but now I know there is no point.
Typical Eric, can't really respond to the facts above so he dances his little dance while saying nothing.
They are not facts.
You just think they are. It's what lies behind these 'facts' which is important.Again - 3 can not reverse 1 with 2 in the middle. Try to get that through your old thick skull.
If you remove 2, then 3 can reverse 1. Simple mathematics, I'll show it to you:
1. 5 * 5 = 25 2. 25 * 0.99 = 24.75 3. 24.75 / 5 = 4.95
That's what the above steps does. Step one is sharpening, step two is JPG compression - a *LOSSY* process and step 3 is blur. Step 3 has *NOT* reversed the algorithm in step 1, we do NOT have the same value as we started with.
Remove the second step:
1. 5 * 5 = 25 2. 25 / 5 = 5
Now the first algorithm (multiplication) has been reversed by the second algorithm (division) and the result is the same as what we started with.
These are *facts* Eric, not guesses or mere claims. This is how mathematics works.
-- Sandman[.net]
09/13/2014-
