User:NikosA

From GRASS-Wiki
Jump to: navigation, search

Nikos Alexandris

Other userpages

Userpage at OSGeo's wiki

Contact

nik at nikosalexandris dot net

To Do

Convert shell scripts to Python

Remote Sensing Stuff

High Pass Filter Additive Image Fusion

ASTER L1B

Shell script to convert ASTER L1B Digital Numbers to Radiances/Reflectances

#!/bin/bash

# Trikala, Greece | 27/28. Oct. 2013

# Converting ASTER L1B VNIR & SWIR DNs to Radiances/Reflectances
  # Note, conversion for TIRs not implemented!



# HardCoded MetaData! ### Adjust as Required #################################
                                                                             #

  # π, first 11 decimals
  PI=3.14159265358
                                                                             #
  # Acquisition's Day of Year and estimated Earth-Sun Distance
  DOY=44; ESD=0.98735
                                                                             #
  # Sun Zenith Angle based on the acquisition's Sun Elevation Angle
  SEA=59.993192; SZA=$(echo "90 - ${SEA}" | bc )
                                                                             #
  # some echo
  echo "Acquisition-specific parameters"
  echo "Day of Year: ${DOY}, Earth-Sun Distance: ${ESD}, Sun Zenith Angle: ${SZA}"
  echo -e "\n"
                                                                             
                                                                             #
#
######################################################## HardCoded MetaData! #



# Product Description ########################################################
                                                                             #

# # This Level 1B product contains radiometrically calibrated and geometrically 
# # coregistered data for all ASTER channels. This product is created by applying 
# # the radiometric and geometric coefficients to the Level 1A data. The bands have 
# # been coregistered both between and within telescopes, and the data have been 
# # resampled to apply the geometric corrections. As for the Level 1A product, these 
# # Level 1B radiances are generated at 15m, 30m, and 90m resolutions corresponding 
# # to the VNIR, SWIR, and TIR channels. Calibrated, at-sensor radiances are given 
# # in W/(m 2 ・ mm ・ sr). This product serves as input to derived geophysical 
# # products.

# Products Summary

# # Resolution : 15, 30, 90 m (VNIR, SWIR, TIR, respectively)
# # Input Band: VNIR, SWIR, TIR
# # Production : 310 scenes per day
# # Science Team Contact : H. Fujisada

#
##############################################################################



# Variables and Constants ####################################################

# check command line parameters
if [ -z "${2}" ] ;
then
echo "List the acquisition's Gain States for the VNIR & SWIR spectral bands, i.e. one of the \"High, Normal, L1 and L2\" separated by space."
echo "Usage: $0 [High High Normal Normal Normal Normal Normal Normal Normal Normal] "
exit 1
fi

# read Gain States
GAINSTATE_1=${1}
GAINSTATE_2=${2}
GAINSTATE_3N=${3}
GAINSTATE_3B=${4}
GAINSTATE_4=${5}
GAINSTATE_5=${6}
GAINSTATE_6=${7}
GAINSTATE_7=${8}
GAINSTATE_8=${9}
GAINSTATE_9=${10}


# Calculated Unit Conversion Coefficients ( W / m^2 / sr / um ) ##############
                                                                             #
# Source: "How to calculate reflectance and temperature using ASTER data",
  # 	Prepared by Abduwasit Ghulam, September 2009
# Source (2):
  #	<http://www.gis.slu.edu/RS/ASTER_Reflectance_Temperature_Calculation.php>
# Source (3):
  #	<http://www.science.aster.ersdac.jspacesystems.or.jp/en/documnts/users_guide/part2/05_03.html>

# VNIR Bands
B1_High=0.676	;	B1_Normal=1.688	;	B1_Low1=2.25
B2_High=0.708	;	B2_Normal=1.415	;	B2_Low1=1.89
B3N_High=0.423	;	B3N_Normal=0.862 ;	B3N_Low1=1.15
B3B_High=0.423	;	B3B_Normal=0.862 ;	B3B_Lo1=1.15

# SWIR Bands
B4_High=0.1087	;	B4_Normal=0.2174	;	B4_Low1=0.290	;	B4_Low2=0.290
B5_High=0.0348	;	B5_Normal=0.0696	;	B5_Low1=0.0925	;	B5_Low2=0.409
B6_High=0.0313	;	B6_Normal=0.0625	;	B6_Low1=0.0830	;	B6_Low2=0.390
B7_High=0.0299	;	B7_Normal=0.0597	;	B7_Low1=0.0795	;	B7_Low2=0.332
B8_High=0.0209	;	B8_Normal=0.0417	;	B8_Low1=0.0556	;	B8_Low2=0.245
B9_High=0.0159	;	B9_Normal=0.0318	;	B9_Low1=0.0424	;	B9_Low2=0.265

# TIR Bands
B10_Normal=0.006822
B11_Normal=0.006780
B12_Normal=0.006590
B13_Normal=0.005693
B14_Normal=0.005225

#
##############################################################################


# Missing: Spectral Band Effective Bandwidth, Δλ #############################
                                                                             #
#
# Some Effective Wavelengths required for the TIRs conversions... ToDo!
#

#
##############################################################################



# Band-Averaged Solar Spectral Irradiance [W/sq.m./micro-m] ( Esun ) #########
                                                                             #

# Commented Columns: 1st: Band #, 2nd: Smith, 3rd: Thome (A), 4th: Thome (B)

B1_Esun=1845.99	#	1	;	1845.99	;	1847	;	1848
B2_Esun=1555.74	#	2	;	1555.74	;	1553	;	1549
B3N_Esun=1119.47#	3N	;	1119.47	;	1118	;	1114
B3B_Esun=1119.47#	3B	;	1119.47	;	1118	;	1114

B4_Esun=231.25	#	4	;	231.25	;	232.5	;	225.4
B5_Esun=79.81	#	5	;	79.81	;	80.32	;	86.63
B6_Esun=74.99	#	6	;	74.99	;	74.92	;	81.85
B7_Esun=68.66	#	7	;	68.66	;	69.20	;	74.85
B8_Esun=59.74	#	8	;	59.74	;	59.82	;	66.49
B9_Esun=56.92	#	9	;	56.92	;	57.32	;	59.85

# 10
# 11
# 12
# 13
# 14

#
##################################################################### Esun ###



# loop over VNIR & SWIR bands
for BAND in 1 2 3N 3B 4 5 6 7 8 9 ; do

  # some echo
  echo -e "Processing spectral band \"${BAND}\""

  # set band parameters as variables
  eval GAINSTATE=GAINSTATE_${BAND}
  eval CUCC="B${BAND}_${!GAINSTATE}"

  echo "* Instructed Gain State: ${!GAINSTATE} // Corresponding Conversion Coefficient: ${!CUCC}"

  # set region
#   echo "* Region matching the ${BAND} spectral band."
  g.region rast=${BAND}_DNs

  # conversion of ASTER L1B DNs to Radiance (32-bit calculations)
  echo "* Converting Digital Numbers to Spectral Radiances..." | tr -d "\n"
  r.mapcalc "${BAND}_Radiance = ( ${BAND}_DNs - 1 ) * double(${!CUCC})"

  # report range
  echo "* Range of calculated Spectral Radiances: " | tr -d "\n"
  # r.info -r "${BAND}_Radiance"
  r.info -r "${BAND}_Radiance" | tr "\n" "," | cut -d"," -f1,2 | sed 's/,/,\ /'
  echo

  # add info
  r.support map=${BAND}_Radiance \
  title="" \
  units="W / sq.m. / μm / ster" \
  description="Band `echo ${BAND}` Top-of-Atmosphere Spectral Radiance [W/m^2/sr/μm]" \
  source1='Update This Field...'

  # Esun
  eval BAND_Esun="B${BAND}_Esun"

  # some echo
  echo -e "* Esun= ${!BAND_Esun} // Earth Sun Distance= ${ESD} // Solar Zenith Angle= ${SZA}"

  # calculate ToAR
  echo "* Converting Radiances to Top of Atmosphere Reflectances..." | tr -d "\n"
  r.mapcalc "${BAND}_ToAR = \
	( ${PI} * ${BAND}_Radiance * ${ESD}^2 ) / ( ${!BAND_Esun} * cos(${SZA}) )"

  # report range
  echo "* Range of calculated Reflectances: " | tr -d "\n"
  r.info -r ${BAND}_ToAR | tr "\n" "," | cut -d"," -f1,2 | sed 's/,/,\ /'

  # add some metadata
  r.support map=${BAND}_ToAR \
  title="echo Band ${BAND} (Top of Atmosphere Reflectance)" \
  units="Unitless Reflectance" \
  description="Top of Atmosphere band `echo ${BAND}` spectral Reflectance (unitless)" \
  source1='"Update This Field...' \
  source2="Update This Field..." \
  history="Pi=3.14159265358; Gain=${!GAINSTATE}; CUCC= ${!CUCC}; ESD=${ESD}; Esun=${!BAND_Esun}; SZA=${SZA}"

  echo -e "\n"

done

Screenshots

EVI2 vs NDVI

EVI2 vs. NDVI

EVI2 based on summer Landsat acquisitions (from 2009 to 2011, histomatched, only tiles that originally fall into UTM Z34N) covering Ellas (Greece)
NDVI based on summer Landsat acquisitions (from 2009 to 2011, histomatched, only tiles that originally fall into UTM Z34N) covering Ellas (Greece)

Map Swipe (g.gui.mapswipe)

Recent addition in GRASS 70: http://grasswiki.osgeo.org/wiki/WxGUI_Map_Swipe

The Greek island Mytilene (Lesvos): swiping a summer Landsat RGB (bands 7, 4 and 2) composite image and an unsupervised classification based on a bi-temporal NDVI image (summer and winter NDVI)
The Greek island Mytilene (Lesvos): mirroring a summer Landsat RGB (bands 7, 4 and 2) composite image and an unsupervised classification based on a bi-temporal NDVI image (summer and winter NDVI)

Scratching ideas for the GRASS-wiki

Various ideas discussed with <http://archi.tect.gr/>

Testing on http://grasswiki.osgeo.org/wiki/User:NikosA/common.css

GRASS-Wiki content maintainance

Various issues

To list...

Upon the use of Templates =

True, content is the foremost essence. In order to ease off content reviewing and management, WikiMedia, upon which the GRASS-Wiki relies, has the Special Pages section. Still, there is a significant need for user input to control the content. Towards a better and easier maintainance mechanism, it might be useful to setup as much as possible Templates which can be used easily across the entire GRASS-Wiki to mark pages and notify readers.

For example, it is not always easy to discriminate between truely OutDated content or simply content that refers to an older version of GRASS. In this case, a notification indicating that the content refers to an older version of GRASS (be it GRASS 5.x) would be, perhaps, a smarter solution than simly marking the page as old. Alternatively, or in addition to a Template, a corresponding Category should be created.

There is, in my opinion, a natural need for some concrete, short, useful set of basic Templates. There are already several Templates. However, the influence in organising the content will be more effective, if the Templates adhere to a basic set of universal rules (think of appearance that invites to get involved) and delivers in a concrete way the "message" (think of short, rational, meaningful notification and/or explanations).

Towards this scope, I support the creation and collection of Templates to cover, if not all, at least the very basic needs to help tag the content.


GRASS-Wiki styling

  • style the tab-bar to approach the grass-gis website?


Ideas for an alternative GRASS-Wiki logogram

File:Current grasswiki logo.png
The current GRASS-Wiki logo... is where?
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram
Alternative GRASS-Wiki logogram

GRASS-Wiki native colors

Should GRASS-Wiki pages wear GRASS' native colors?

Or else... ?

Some random example: light grey font-color (#dcdcdc), green border (#4da948)

Better typography

Review and possibly alter:

  • linespacing (between hierarchy elements!)
  • indentation of code blocks -- might improve readability
  • (non-code) text wrapping -- narrower body text column, easier to read
  • move ToC on the right, make it fixed! This will "save" some long pages!
  • move Categories right below the ToC -- also useful inside long pages


Some proof-of-clean-typography screenshots

First impressions of a custom css designed by <http://archi.tect.gr/>

Holistic Look & Feel

GRASS-Wiki, better typography!

GRASS-Wiki, better typography


GRASS-Wiki, better typography

Elements

The very left column is like a Wiki's connection terminal -- it should look and act like that for the user. It should also clearly state GRASS-GIS' identity.

GRASS-Wiki, the main Toolboxes on the left should state GRASS-GIS' robust, clean and open identity
GRASS-Wiki, the main Toolboxes on the left should state GRASS-GIS' robust, clean and open identity


Better typography is not only about aesthetics. It's about readability and making things easier to study. The screenshot below speaks for itself. Hint: the ToC is always accessible, following the user's eyes!

GRASS-Wiki, better typography, ToC follows scrolling down and therefore always visible


The Table of Contents is a must have for page-content organisation and navigation. Can it be *always* accessible while not distracting the user from reading when not required? Yes, it can.

GRASS-Wiki, semi-transparent ToC, fixed on the right
GRASS-Wiki, semi-transparent ToC, fixed on the right
GRASS-Wiki, clean ToC when hovering over with mouse pointer, fixed on the right
GRASS-Wiki, clean ToC when hovering over with mouse pointer, fixed on the right


The Categories bar, finally can receive the attention it deserves!

GRASS-Wiki, clean and attractive Categories bar
GRASS-Wiki, clean and attractive Categories bar


Related sources:

Distance between ToC and 1st Section

Match Media-Wiki's bigger distance from ToC to 1st Section!

GRASS-Wiki, distance between ToC and 1st Section
GRASS-Wiki, distance between ToC and 1st Section
Media-Wiki, distance between ToC and 1st Section
Media-Wiki, distance between ToC and 1st Section

Distance between Sections

Seems to be the same, for some reason, anyhow, some lengthy GRASS-pages look overfilled/noisy!

GRASS-Wiki, distance between Sections
Media-Wiki, distance between Sections

The GRASS-Wiki Special Pages are nicely structured, easy to read. Is there, and what exactly, a formatting difference with the "dafault" GRASS-Wiki pages?

Distance between Sections in GRASS-Wiki's Special Pages page

Various Links