
Processing the Viking Lander camera data [pdf] - daledavies
https://saltworks.stanford.edu/assets/zz000vd6201.pdf
======
eliteraspberrie
You can reproduce some of the image processing described here with software
today.

For example, in Figure 3, the histogram at the top right is a "periodogram" of
the original image data. It shows that the original image is skewed towards
the high end of the frequency spectrum. They apply a high-pass filter (discard
the lowest frequencies) so the processed image shows higher details than the
original.

If you had the original photograph as an image file, let's say an image of the
surface of Mars, [0] you could filter out the lowest ten frequency components
with a Python script: [1]

    
    
        pip install avena
        avena filter high 10 pia19676-fig1_ml_mcam04403coloradjusted24bwscale.jpg
    

The result: [http://imgur.com/a/ASusx](http://imgur.com/a/ASusx)

Notice the details are more visible.

[0] [http://www.nasa.gov/jpl/msl/pia19676/geological-contact-
zone...](http://www.nasa.gov/jpl/msl/pia19676/geological-contact-zone-near-
marias-pass-on-mars)

[1] (shameless plug)
[https://github.com/eliteraspberries/avena](https://github.com/eliteraspberries/avena)

~~~
mmd
This mission was also interesting from onboard computing side. NASA history
page has some cool info about that:
[http://history.nasa.gov/computers/Ch5-6.html](http://history.nasa.gov/computers/Ch5-6.html)

------
jakeogh
About two years ago the Avaneya project released software that can decode the
Viking Lander tapes. A few tapes contain images that were (as far as I know)
never released.

Beautiful results:
[https://gist.github.com/jakeogh/fa995a3277d500ab59b1](https://gist.github.com/jakeogh/fa995a3277d500ab59b1)

There's even a very nice DVD which takes the included raw tape data and
processes it:
[https://directory.fsf.org/wiki/Avaneya:_Viking_Lander_Remast...](https://directory.fsf.org/wiki/Avaneya:_Viking_Lander_Remastered_DVD)

