Charts II: NGA - 2700 Charts

[Surveyor]

Originally Posted by Tia Bu

This works better, but the largest charts still crash and burn on my machine. I don't know if this is relevant to the web-based calibration project. Would we actually be manipulating image files and doing calibrations on our computers, or would we just be entering data for the images to be processed on a server somewhere else?

The way I understand it, the process will be as automated as possible on the server side. The server will have a set of 4 corners cropped from each chart. We will download those, determine the pixel offsets to known points (borders usually). We will then enter that data and any other relevant data in a web form and the server will process the calibration and produce the kaps.

I do believe that the server side will also process the size, colors etc of the jpgs . They are working on determining the best solution to this now. Rotating skewed charts may be problematic but my understanding is that we will start with the easy cases first.

[sinbad7]

If anybody has problems with the huge NGA file sizes,I can recommend BatchImageResizer.

I usually reduce to 40% to get a reasonable end resolution.

The program does not display the chart so it does not blow your RAM.

Tore

[HappySeagull]

full sized,viewed from files on a usb drive with a 768mb ram XP machine.True,I have to wait,and I can't do much with them on screen unless I bake bread while I'm waiting,but at least I can see 'em.WHY can't you guys with new computers ,big ram and fast busses see em?I'd have thought you'd be able to turn em in somersaults.
It's crazy.why aren't new computers BETTER than the old ones.

[Surveyor]

I dont have any trouble on a Core i7 Win7-64bit 8gb ram 2gb video laptop even with the largest charts. I think the guys running certain versions of linux dont have trouble either as memory management is much better in linux.

[dacust]

Also, I don't think people are having problems viewing the finished chart in OpenCPN. They are having problems viewing the raw .jpg in their various graphics programs.

[sinbad7]

I repeat again.. download the free BatchImageResizer and all your troubles are over.
You don't view the raw NGA file,just reduce the size (40% is great) with other enhancements and save as .png, after which you can view the reduced bitmap.

Do a 'google' for the best place to download it.

Tore

[Surveyor]

Originally Posted by sinbad7

I repeat again.. download the free BatchImageResizer and all your troubles are over.
You don't view the raw NGA file,just reduce the size (40% is great) with other enhancements and save as .png, after which you can view the reduced bitmap.

Do a 'google' for the best place to download it.

Tore

Tore, would you mind looking at your BatchImageResizer "about" tab or button and telling us who the developer is, a version number or something.

Googling BatchImageResizer I find 10 or 15 different programs all by different developers, some freeware, some shareware.

[sinbad7]

Hi Jim..

Mine is an older (trial) version but you can download a current one here for US 29.95.
Batch Image Resizer - Resizing batch images quickly!

I see many offer it as freeware so perhaps you should try those first.

My version includes all I need and does not seem to be restricted or time limited.
The only thing is it does not seem to reduce colours.

I have a laptop running Vista and 2 GB RAM but could not open ANY of the NGA files.


Tore

[dacust]

Originally Posted by Surveyor

Tore, would you mind looking at your BatchImageResizer "about" tab or button and telling us who the developer is, a version number or something.

Googling BatchImageResizer I find 10 or 15 different programs all by different developers, some freeware, some shareware.

This is not batch, but you can shift-select a large group from Windows Explorer and do it in a batch, albeit interactively. And they are both free.

If you have XP, download the resizer from the Microsoft PowerToys site:
==> Windows XP downloads - Microsoft Windows
Then click on the "PowerToys" tab one row down the page. Then, on my screen, it is on the 2nd row, 2nd column. "Image Resizer"


For Win7:
==> Image Resizer Powertoy Clone For Windows 7/Vista

This one is not by Microsoft. But I have been using it for almost a year now. Actually, there were a couple things about the MS one that very slightly annoyed me. They fix them in this version. Like it remembers all my settings.

-dan

[HappySeagull]

...that is the full sized 137 mb jpeg.It'd be nice to just throw it around in MapCal ...But,there's hope,I see,from Surveyor's post.I'll get one of those 5 years from now

[phiggins]

You should try nconvert, its free, runs on Linux and Windows . Even on my XP system with 1 Gig of ram it can resize the jpgs and it can do muliple of them at once. Also reduces the colors and rotates them if necessary.

Here is the command I run in a CMD prompt to do all the pngs:

nconvert -out png -colors 64 -resize 50% 50% *.png


NConvert Software - Free graphic and photo batch converter

[Surveyor]

There are 50 very interesting charts sitting in the incoming directory on the server. Is there any chance of sharing those? They are very very interesting!!!

[cagney]

Originally Posted by Surveyor

There are 50 very interesting charts sitting in the incoming directory on the server. Is there any chance of sharing those? They are very very interesting!!!

As a temporary solution I created the directory "/misc" in the normal ftp download place. All the chart images from "incoming" are copied to "misc".
Thomas

[paulr]

Originally Posted by cagney

As a temporary solution I created the directory "/misc" in the normal ftp download place. All the chart images from "incoming" are copied to "misc".
Thomas

Great work!

82534 appears to be missing (looking at it, I doubt it is going to be one of the first to be converted!)

Paul

[cagney]

Thanks Paul
82534 uploaded now.

I think you're right about this chart. A bit fiddly to geo-reference a sketch chart containing just one fuzzy position.
No one in their right mind would ever think of plotting a position etc. on a paper version of those small sketch plans. Generally a look at the sketch, what you see with your eyes, a glance at the compass and your depth sounder is all that is needed, to find a spot to drop your anchor.
But... when (or if!) we make an electronic version ... who knows how "serious" they will be used? Specially with quilting on, blending with the smaller scale main chart.

Thomas