How to view the .raw databases?

[Piotr]

I want to see the .raw database, known as Stylized World Topo 5400x2700.raw. Please add an option to convert geo.raw to .png format.

[daan]

I want to see the .raw database, known as Stylized World Topo 5400x2700.raw. Please add an option to convert geo.raw to .png format.

Convert within Geocart and save out to a PNG file? Why? Geocart is not an image format processor.

You can see the .raw database by make a map with it. The image is in plate carrée projection, so if you use that projection, you will see it undistorted.

— daan

[Piotr]

I can't get it to view at regular size though.

[Atarimaster]

I can't get it to view at regular size though.

Why not? What seems to be the problem?
What exactly did you try and what happened then?

[Piotr]

1. I made a new map. I set the projection to plane chart or plate carree.

2. I checked map size and resolution. The pixels/point is 1, and I looked at point size. I saw 723x363, which is not a 2:1 ratio. After some experimenting, I realized that it's 720x360, with 3 pixels added to width and height.

3. I set the width to 5403 points. However, the map is now 5402x2702, which is wrong.

4. Then I tried to set height to 2703 points, but the map was resized to 5404x2704.

Also in both cases I got from 3. and 4., the boundary lines weren't perfectly aligned with pixels like they did when the map was default size.

[daan]

Because monitors are not all the same resolution, and because Geocart creates its maps precisely according to the geodetic datum and display resolution, the settings you would use see the exact pixels of an image vary from computer to computer. This is what to do:

1. In the Preferences menu, General panel, Display pane, make sure your monitor resolution is calibrated correctly. See manual if you need help.
2. Create your map, selecting plate carrée on the Cylindric menu.
3. Set your database to the one whose pixels you want to examine.
4. Select the map, and choose “Actual Pixels of Selected Object” from the View menu. This ensures that each pixel on the screen coincides with a pixel in your image.
5. Use “Draft Quality” on the Map menu. This prevents pixels from getting blended together.
6. Set your datum to some Spherical datum, such as “Sphere: GRS 80 authalic”. This is the default.
7. Note the radius of the earth for your datum. In this case, it’s 6,371,007.180918_m. That means the equatorial circumference is 40,030,218.7110796_m = 40,030,218,711.0796_mm.
8. Note your monitor’s pixel resolution in mm. In my case, it is 3.97638 pixels/mm. Therefore the earth at full size would have 3.97638 * 40,030,218,711.0796 = 159,175,361,078.363 pixels on my monitor.
9. Note the pixel width of your image database. In this case, it is 5,400 pixels. That means the nominal scale for you map must be 159,175,361,078.363/5,400 = 29,476,918.7182154 : 1 (because 159,175,361,078.363 pixels on earth is to be represented by 5,400 pixels in the image).
10. In the Map menu, Nominal Scale setting, set the 1 : XXX value to what you computed in the prior step.

Now you will see each pixel as it is in the selected database, without processing or scaling.

While the complication is unfortunate, the reasons are important. Meanwhile most people wouldn’t use Geocart to view raw pixels. They would open the image in something like Photoshop or a freeware application, of which several seem to be available.
— daan

[Piotr]

I tried using a raw pixel viewer, trying to find the correct settings, and I got this false color image:
I'm sorry, but this image cannot be uploaded due to weird things done by imgur.com.

Probably there are some header bytes at the beginning. How many?

[daan]

128

[Piotr]

Thank you! I got the map.