formats for schematics/scans

Started by rocket, January 28, 2005, 07:23:56 AM

Previous topic - Next topic

rocket

Hello,

all the guys who scan schematics to post them please use GIF or PNG rather than JPG/JPEG which creats ugly artifacts that make reading much more difficult.

thanks for all your effort

loscha

Yes,  a low quality JPG will leave artifacing, no question, but, sometimes a PNG or GIF file will be significantly larger than the high qual JPG.
My recent Metal Zone/Izer scans were a tough call, the GIFs were much bigger, and the PNGs were Huge.

The reality is that we don't all have boradband internet yet, but, we all care about the quality of our scans. I care about the scans I give out. The day I get broadband, there are going to be lossless PNGs of all my stuff online. I've got actual gigs of schematics here that I've scanned and tidied up, but, until I get me my broadband, I've got to trade-off.

It's the age old problem
money is the obstacle to pure artistic expression
which part of sin theta plus index times sin theta times ratio do you need me to clarify to you?

RedHouse

Ya know, now that you mention it, I don't have any probem reading JPEG's created by anyone here. Oh maybe every once-in-a-while an over-compressed JPEG floats by here (are you aware there are levels of JPEG compression?).

Is it that you're you trying to use them as PCB artwork? if so just pull the funky ones into Photoshop and clean 'em up. Isn't it better to do your own work than burdon everyone else in the world? just a thought.

loscha

yeah, every real photo editing program in the world has color gradient functions and fuzzy-logic erasers, sharpening filters.

I've not come up against one schematic that I haven't been able to make usable.
I've got a folder here, I print out a lot of schematics, keep them in pockets so I can hapily browse them, looking for ideas, prompting my memory as to certain things, just generally have a good time.....

My partner finds it wildly funny that me and my tech friends refer to our schematics and service manuals as our Porn, and have discussions over the new centrefolds we have gotten lately. She just shakes her head and goes "you guys....."

Ain't no porn mag as sexy as the day I got my Metalizer schematic in the mail and I folded out that master circuit diagram.....

fap fap fap
which part of sin theta plus index times sin theta times ratio do you need me to clarify to you?

Rob Strand

QuoteYes, a low quality JPG will leave artifacing, no question, but, sometimes a PNG or GIF file will be significantly larger than the high qual JPG.

They are only large because you are using too many colors - yet another problem with a lot of schematic scans.  The number of colors has a big impact on gifs.  I actually prefer png for schematics.  

I took one of your files and converted it to png:

was mt2-06.jpg  335kB
now mt2-06.png  164kB

It can be made quite a bit smaller if you optimize the size too.

If you threshold the background you can get rid of all the speckle out of the background which looks much better for printing.  In fact I can actually  get rid of a lot of the jpg artefacts this way.

Let's face it, in most cases, .jpg sux for schematics.  Unfortunately most people use .jpg for scans!!
Send:     . .- .-. - .... / - --- / --. --- .-. -
According to the water analogy of electricity, transistor leakage is caused by holes.

Eric H

Haven't seen your name for a while, Rob --welcome back.

-Eric
" I've had it with cheap cables..."
--DougH

Rob Strand

QuoteHaven't seen your name for a while, Rob --welcome back.

Hi Eric!

These days I come and go infrequently in various alien forms :)--|--<.
Send:     . .- .-. - .... / - --- / --. --- .-. -
According to the water analogy of electricity, transistor leakage is caused by holes.

Eric H

Quote from: Rob Strand
QuoteHaven't seen your name for a while, Rob --welcome back.

Hi Eric!

These days I come and go infrequently in various alien forms :)--|--<.
So that WAS you ;-)

I know what you mean.

-Eric
" I've had it with cheap cables..."
--DougH

niftydog

some things that I do to ensure small files;

use minimal colours

ensure colours are HTML compatible

save as GIF (especially if only black and white)


Even better would be to use a vector grahpics program like Flash or Freehand or Illustrator... but not everyone has access to those.
niftydog
Shrimp down the pants!!!
“It also sounded something like the movement of furniture, which He
hadn't even created yet, and He was not so pleased.” God (aka Tony Levin)