Re: Raw picture reduction

Woody <usenet@xxxxxxxxxxxxxx> wrote:

Rowland McDonnell <real-address-in-sig@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

Woody <usenet@xxxxxxxxxxxxxx> wrote:

Rowland McDonnell <real-address-in-sig@xxxxxxxxxxxxxxxxxxxxxxx> wrote:
Woody <usenet@xxxxxxxxxxxxxx> wrote:
[snip]

('ere, Woody, whatever your news client is, it's buggering up quoting
when it line wraps)

Is it?

I wouldn't have said so if MacSoup didn't barf when trying to re-wrap
the stuff your newsreader buggered up. Actually, it's not so bad, but
ugly and MacSoup gets confused by it.

that is newstap on either the iPad or iPhone (I used both today)

Ah.

you've got a lot of data and are looking for savings - fine. But 25MB
is still not a lot, for all that it'd useful to squeeze down `a big pile
of high quality images if you really need to save space'.

It is a lot, I have 650 of the files, so 16GB at 25M.

16GB is 320/16 or `only 5% of the disc space in question'.

Actually probably more, I got the file size down more than that
difference.

I've got a 20MB HDD. Yes, *mega*bytes - hooked up to my Mac Plus (well,
not actually plugged in at the moment - stuck at the bottom of the spare
room wardrobe as it happens).

I think we all do somewhere. The powerbook has a 40MB drive, and I have
a spare 20MB drive that I assume still works in my pile of things I
never look in and should throw in the skip

NOOO!!!!!! Stick it up on Freecycle or somehow give the kit away rather
than binning it. That's industrial archaeology, that is.

[snip]
Umm. If you can see differences, then you are seeing compression
defects.

Ok, well in that case both jpeg and jpeg2000 are defective by design,
as they appear immediately.

Not at all - the *point* is to introduce defects, so as to save on
space. The other point is that the defects introduced by JPEG2000 are
less nasty than those introduced by original JPEG.

But failed to replicate that in my tests

I'd like to see what you saw - my tests, and bear in mind that I did
*NOT* expect to see any improvement from JPEG2000 /at all/ - my tests
showed a huge improvement.

Come on, you saw the benefits of JPEG2000 in the example I sent, didn't
you?

I did. It was clearly a lot better, and that is what I was hoping for
with my tests.

But you didn't see it doing /your/ tests - well, in that case, how about
you install Graphic Converter and see what you can see using it to do
the conversions? Now we've had it confirmed that it'll deal with CR2s,
why not?

[snip]

jpeg 2000 certainly produces a less troubling degredation at higher
compression ratios (on smaller pics, these are all 3500 x 2900) where
the jpeg comes up with the cell patterning, allthough at full
compression, where the jpeg is badly squarey, the jpeg2000 has a huge
line through it

Huh? What what what? Go on, email me with this one, I'd like to
see it.

Ok. I think it is something to do with block size, as there was a
control for that

I've not seen any email from you. Did you send me anything?

JPEG2000 doesn't use blocks. It works on wavelets, which is `doing
the job properly'.

Well, there was a control that mentioned the word block and was set to
1024

Ah. Word blocks - dunno about that, sounds to me like something in the
stored data structures unrelated to the image side of things, IYSWIM.

Image blocks is what you have in JPEG, and - ooh, therein lieth the
fault. JPEG2000 works on wavelets as the `basic unit to compress'.
Wavelets are `what the image is made out of'. It's why JPEG2000 is
guaranteed to work better - as I found out after I'd seen that it *IS*
better.

Just looked again, it is 'tile blocks'.

Huh? Strange. No idea what that's on about.

But a quick Web search shows that yep, that applies to JPEG2000-type
stuff:

<http://www.freepatentsonline.com/7251375.html>

"Tile boundary artifact removal for arbitrary wavelet filters

United States Patent 7251375

A method for processing data is described. In one embodiment, the method
includes decompressing a plurality of sets of compressed data, including
performing detiling on a first set of compressed data using neighbor
information from at least one other set of compressed data, and
recombining the plurality of decompressed tiles into an image."

But the only things I can find on the subject doing quick Web searches
are patent-related so I'm damned if I can figure out what's what.

Ooh! Aside from this:

<http://www.cipr.rpi.edu/~choy/thesis.pdf>

which you might be able to make some sense out of, assuming you don't
mind Computer Modern Roman ;-)

I get the option of 1024x1024 as
a default, and then at binary intervals down to 128x128.

I didn't play with them to see what they did.

FWIW, I see no such controls on Graphic Converter.

So my first guess is: Graphic Converter has a competent means of dealing
with tile block artifacts, while Photoshop's JPEG 2000 encoder hasn't.

[snip]

Cocoa used to be a full-on programming environment long before MacOS
X. It was a graphical programming language for young childen - from
Apple, no less. Can I find one single reference to it on the Web these
days? Nope.

I have never heard of that before. Cocoa became cocoa after the
developer release of rhapsody, what was to become osx.

There you go then.

You are not confusing this with smalltalk were you?

<cough> Is Smalltalk a graphical programming language that lets kids
build - oh, I've sent you the manual, check your in-box.

No. Although it often has a graphical interface, but that isn't it.

That is interesting, never heard of that at all!

Cocoa was a 1990s Apple thing - purely graphical. Smalltalk was a
1970s-originating thing, purely textual, and not for children.

Part of the origins of smalltalk was a language that was simple enough
for children to use.

That might have been some mad computer scientist's original idea, but
none of the examples of Smalltalk that I saw on the Wikip Smalltalk page
were suitable for anyone not working - these days - at least at degree
level (typically). They'd not attempt using anything looking like that
at GCSE. Maybe A level, for the serious students.

Objective c which is
the language that is generally used to create cocoa interfaces has a
history that draws some techniques from smalltalk, although is very
dissimilar in other ways

Check your in-box.

Smalltalk was made for children to be able to control computers
originally,

Not from what I've just read about it. The examples I've seen show it's
not at all suitable for young children at least - you'd want high school
kids who are keen on computers and good with words, not `any old
youngster'

Well, yes, probably kids of around 10 upwards.

Not what I've seen. Kids of 16 and upwards, but only really keen and
intelligent 16+ year olds.

Show me some examples of how Smalltalk might be suitable for those
younger than that.

I put it to you that the typical ten year old on facing this sort of
stuff:

aRatherBigNumber := 42 factorial

or

Object subclass: #MessagePublisher
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'Smalltalk Examples'

(examples taken from Wikip)

would just switch off. It's got fussy syntax, fussy rules about
objects, doesn't read like any natural language I've ever heard of, and
generally displays all the characteristics that make modern programming
so inaccessible to the general population.

and is a nice language for teaching.

So it is said - but you know what? The examples I've just looked at
make it look like a complete nightmare to use for anyone.

It is very simple, especially if you don't know anything at all about
computers.

No it's bloody not!

Unfortunately it is a bit of a pain if you do it in your degree computer
science course. Unfortunately it is too little to teach anything much.

I think you must be confusing Smalltalk with something else entirely, I
really do.

Modula-2 is a nice language for teaching. I did once start to learn
Pascal and that didn't bother me, so I assume even I'd get on with
Modula-2.

Pascal was used extensively for teaching in the US. For some reason, we
got basic.

Basic was invented in the USA for teaching. Pascal was used extensively
for teaching in the UK.

But in the UK and in the USA, almost all second generation home micros
came with Basic.

One reason for Basic perhaps being used a bit more in the UK was that we
didn't have to put up with MS Basic, as was near-universal in the USA.

We had better forms of Basic - in particular from Sinclair and Acorn
(the latter giving real structuring commands, real local variables, and
other such `real programming' goodies).

I do believe that you
would gain more from teaching a child smalltalk than office but the
crapness of computer science education (rather than IT) is another
matter

You'd gain more from teaching them anything other than MS Office.
Cookery would be a good start. I saw two late teens girls in Tesco one
time, looked like they'd just left school and got a flat together as
mates so they could afford to live away from parents. They didn't have
a lot of money (I was eavesdropping shamelessly) but ended up buying
tinned pasta because they couldn't work out how to cook the dried stuff.


They do cooking at school.

Not generally, they don't.

Well, my daughter did - home economics
anyway. Maybe it is an option.

Hmm - home economics is generally not on the curriculum at all from what
I've heard. And what counts as `home economics' these days is nothing
like the genuinely useful home economics that my mother learnt when she
was young.

These days, I'd tell 'em, and give 'em a few tips on economical living
for the young (having been a student myself, I have more than a few such
tips) - but that was about ten years ago, and back then I was
uncomfortable about striking up a conversation with a couple of random
just-out-of-school-girls. Not that it's the sort of thing I do these
days generally, but I'm less bothered about talking to people.

There is little-or-no computer science education in UK schools that I
know of.

No, I was suprised to see what constitutes computer science education in
schools. I assumed it would be a lot easier now, but it isn't.

My point is that hardly anyone actually does computer science - mostly,
the kids just do `IT training'. Bash the use of a keyboard and MS
Office into their skulls to turn them into MS-slurping office-working
cabbages, that's the idea.

Oddly enough, it's not working out too well...

Rowland.

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