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The Icon Bar: Programming: Ooooh....
 
  Ooooh....
  Phlamethrower (16:53 20/1/2001)
  ToiletDuck (17:57 20/1/2001)
    Phlamethrower (20:28 20/1/2001)
      tfountain (23:31 20/1/2001)
        andreww (19:23 22/1/2001)
          johnstlr (19:57 22/1/2001)
            andreww (12:45 23/1/2001)
              Phlamethrower (16:02 23/1/2001)
                andreww (19:46 25/1/2001)
                  Phlamethrower (19:58 25/1/2001)
 
Jeffrey Lee Message #86322, posted by Phlamethrower at 16:53, 20/1/2001
PhlamethrowerHot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot stuff

Posts: 15057
Hello

monkey

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Mark Quint Message #86323, posted by ToiletDuck at 17:57, 20/1/2001, in reply to message #86322
Ooh ducky!Quack Quack
Posts: 1016
ohhh its nice and spinkey clean monkey
lets not spoil it grin
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Jeffrey Lee Message #86324, posted by Phlamethrower at 20:28, 20/1/2001, in reply to message #86323
PhlamethrowerHot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot stuff

Posts: 15057
Looks like the forums mucking up again Tim, there's a 'none' post listed....
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Tim Fountain Message #86325, posted by tfountain at 23:31, 20/1/2001, in reply to message #86324
AA refugee
Posts: 59
ARGH. Ahem.
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Andrew Message #86326, posted by andreww at 19:23, 22/1/2001, in reply to message #86325
AA refugee
Posts: 555
Well this is quite an empty thread!
So, Lee could you tell me more about the theory behind your blur code? Is it based upon shifting of pixels or manipulation of pixel values? (I haven't had a look at the relevant section in the assembler source yet)

Andrew

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Lee Johnston Message #86327, posted by johnstlr at 19:57, 22/1/2001, in reply to message #86326
Member
Posts: 193
Blur code??? *Panics* Shurely Shome Mishtake. Shurely you mean Jeff?
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Andrew Message #86328, posted by andreww at 12:45, 23/1/2001, in reply to message #86327
AA refugee
Posts: 555
Yes, sorry, Jeffrey!
:-O
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Jeffrey Lee Message #86329, posted by Phlamethrower at 16:02, 23/1/2001, in reply to message #86328
PhlamethrowerHot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot stuff

Posts: 15057
Aren't similar names fun...

Right, erm, from what I can remember (As I'm on the PC now), there are 5 blur/fade types i've stuck in...

1. A simple fade, where 1 is taken away from each pixels component (R,G,B) until it reaches black

2. A fractional fade, where each component is multipied by the fade amount, shared by 256, then cut down to whatever constraints are needed

3. A 9-pixel mean blur (What you're interested in).
The components of the 3x3 source grid are totalled up, then shared by 9. For 16bit I use some quick division code (I think), while for 24 bit I use a lookup table (since fast and accurate code is a bit tricky for 8 bit). The components are then squashed back together, and stored in the output bank. The exact way the code works for each colour depth is complicated, so it's best to look at the source. Each pixel has identical 'weighting' by the way, although making things like the central pixel more prominent could be easily done (Note to self: Add for next release). Except that I think my current code won't work like that unhappy

4. A 'plasma' effect. This is essentially the 9 pixel mean, but uses some 'experimental' /9 code, which actually shares by about 7.5. This means that each component (providing it isn't black) increases in colour, until it overflows into the component next to it. Also because it's overflowed it resets to black. This gives you some interesting colours from a white dot, instead of a load of grey.

5. A plain block to block copy. What fun.

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Andrew Message #86330, posted by andreww at 19:46, 25/1/2001, in reply to message #86329
AA refugee
Posts: 555
Thanks Jeffrey, that's interesting. I was wondering about the theory behind blurring and I see that it's a matter of taking averages which is a clever trick.
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Jeffrey Lee Message #86331, posted by Phlamethrower at 19:58, 25/1/2001, in reply to message #86330
PhlamethrowerHot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot Hot stuff

Posts: 15057
And once again the forums are doing their best to stop us viewing both posts here!
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The Icon Bar: Programming: Ooooh....