http://www.dintelligent.com/conic-projection/
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conic projection
How do I convert the projection of a raster image?
I have some aeronautical (FAA) charts in a lambert conformal conic projection and I'd like to convert them to Mercator to overlay on google maps. Are there any easy to use free programs for doing this? There is no geo-reference information with the file- it is just a raster image.
Any details on adding the geographic information would be appreciated. An example of part of one of these charts can be found here: http://www.flightsimbooks.com/13mike-ifr/262-1.jpg As you can see, lines of latitude and longitude are on the chart.
This is probably a two step process: 1) You'll have to assign some sort of geographic referencing to your Lambert Conformal Conic (LCC) projected chart and 2) You'll have to reproject the data from LCC to Mercator.
For the first step, if lat/long coordinates are available anywhere on the map you should be able to find the corresponding LCC point for the map and tie that coordinate to the map by determining the raster pixel location for the lat/long point and assigning the LCC coordinate to that pixel point. Gdal utilities, specifically gdaltransform should assist you in this effort to find the proper coordinate values.
For the second step, again look to gdal utilities and consider using gdalwarp. There's a lot of nice tools in the gdal utilities that help not only warp but also convert raster data formats.
I know you asked for easy to use and free, and while gdal is free it's not the easiest thing to use. For easy, you may want to consider checking out the geographic calculator from www.bluemarblegeo.com for an easier approach, although it's not free.
Lastly, you may want to consider the use of commercial GIS software to accomplish this task. That's probably the easiest but highest cost alternative.
Good luck!
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Global Concepts in Maps (Highlights) - 1947
Hi, JT here. I recently received a Projection Alarm Clock as a gift and thought that it was just the coolest thing ever. I've started giving them to friends and thought I'd do a little research and put a site together about Projection Clocks and Atomic Clocks. I hope you enjoy!
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Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!
Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!
Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!
Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!
Map projections were created to display the 3D earth in a 2D space by distorting reality in order to preserve area, direction, distances or shape. The wonderful alternative projections below won’t help you navigate an ocean, they just look awesome.
gawkerGallery(5436487,13,); Anyone who has ever attempted to adjust a map projection in a digital mapping program knows they’re basically large algorithms designed to distort the points and vectors used to represent the earth in order to make the shapes you see on a computer screen or map.
Tweak it the right way and you present data in a way people will understand. Make a mistake and you’ll wind up with something like the images shown above. The Albers Equal Area Conic Projections never looked sexier.
These were carefully distorted by Andy Woodruff at Cartogrammar who has more skill than us. Usually, our accidental projections look more like this.
[Cartogrammar]
Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!
Well I don't go asking for papers to be answered. Why don't you ask your teacher for help or ask a friend? Trust me you'll thank me later!