trws-tutorial-2

Your first experience at Tarawa atoll, Kiribati

Activity nothing to do for now, just read below
Raw data raw data is in /data/tarawa-full.tif use OpenEV to export it to /data/tarawa-full.pix Georeferencing the -MakePIX/.... procedure takes its georeferencing from the -dB/...........argument the -Mis/..........argument the -Import/.... argument the shapefiles need to be prepared over a backdrop image which is properly georeferenced.	Shapefiles OpenEV only writes .shp, .dbf and .shx *4SM calls up shp2text* in order to** read the shapefile write a SHP.txt textfile then proceed to use it as appropriate for working out the geometry and georeferencing of the image subset querrying a pixel modeling a pixel profiling : dynamic memory allocation allows for very long profiles recoding of ROI in mask_SE sampling of ROI you name it!!!
working database tarawa-subset.pix Get acquainted with its 28 channels -DB/.../27_1_0_0/... 1_U8_Raw_550 nm 2_U8_Raw_650 nm 3_U8_Raw_850 nm 4_U8 Special_Effect_mask; use pctmSE 5_U8 wZ: use pctwZ 6_U8 wR: use pctwR 7_U8 Z0->250 in dm: use pctZ250 8_U8 Z: use pctZ20 9_U8 B: use pctB 10_U8 Bottom Typing: use pctClassified 11_U8 LSBCC_blue 12_U8 LSBCC_green 13_U8 LSBCC_red 14_U8 dZED: use pctZ250 15_U8 BPL_12 15 16_U8 BPL_13 16 17_U8 BPL_23 17 18_U8 void18 19_U8 void19 20_U8 void20 21_U8 void21 22_1_U8_Deglinted_Green 23_2_U8_Deglinted_Red 24_3_U8_Deglinted_NIR 25_1_U8_WaterColumnCorrected_Green 26_2_U8_WaterColumnCorrected_Red 27_3_U8_WaterColumnCorrected_NIR 28_S16_ZG_Zretrieved in centimeters	working database tarawa-subset.pix Get acquainted with its future content No worries with this: 4SM shall complain if you do not specify enough channels And it does not hurt if you have more than enough. The thing is: For a N bands 16 bits raw image, you need NU16 bands for raw 16U data NU8 bands for U8 scaled raw data NU8 bands for deglinted data NU8 bands for water column corrected data Plus at least 14 U8 channels for various uses That is at least 4N + 14. For a 3 bands U8 SPOT image,* that is at least 43+14=26 U8 channels For a 4 bands U8 Landsat TM image* that is at least 44+14=30 U8 channels For a 6 bands U16 Landsat 8 image* that is at least 4*6+14=38 U8 channels
	channels 1, 2, 3 Tarawa-subset_Raw_Image a spectral raw image subset, heavily glinted.
OpenEV pseudo-color pallets=====>>>>> They are located in ./4sm.calls/pct=====>>>>>
	channel_4 Tarawa-subset_mSE this is the special effects mask Blue:...........mSE=2 over open waters Orange:.......mSE=3 in the lagoon Red:.............mSE=4 in the lagoon Brown:.........mSE=248 for lands areas Please note that, over the orange area, the higher foreshore is exposed, therefore mapped as land
	channel_5 Tarawa-subset_WZ with following codes Grey...........for clouds Brown........for dryland Dark Blue..for wZ=240: optically deep pixels Blue............for WZ=1 where Depth is computed using Lbref[1] and band_1 alone the ONE-BAND solution Green.........for WZ=2 where Depths are computed using both band_1 and band_2 the RED solution Red........... for WZ=3 where Depths were computed using band_1, band_2 and band_3 the NIR solution
	channel_6 Tarawa-subset_WR Smoothing Window Radius (kernel) with following codes Black No_smoothing on land, clouds, etc Green Radius=5......average of 81 pixels Light Blue Radius=4......average of ... pixels Red Radius=3......average of ... pixels Yellow Radius=2......average of 9 pixels Pink Radius=1......average of 5 pixels Syntax_Smooth
	channel_7 Tarawa-subset_Z250 Depths in decimeters, range 1-250 with following codes Yellow for non-marine areas Shades of blue for depths up to 25 meters Deep blue for optically deep areas
	channel_8 Tarawa-subset_Z20 Depths in decimeters coded for screen display of no interest here as the depth does not exceed 25 m Yellow for non-marine areas Shades of blue then green for depths from 1 meter up to 25 meters Pale green for optically deep waters
	channel_9 Tarawa-subset_B Average Bottom Reflectance is scaled from 0 to 200 see legend for image B
....	channel_10 Bottom typing not in use with SPOT XS images
....	channels 11, 12, 13, 14 are of no interest for a SPOT XS image
	channels 15, 16, 17 channel 15 exhibits BPL pixels for the pair 1/2, i.e. for the Green vs Red pair channel 16 exhibits BPL pixels for the pair 1/3 i.e. for the Green vs NIR pair channel 17 exhibits BPL pixels for the pair 2/3 i.e. for the Red vs NIR pair They are displayed here as a color composite
.........	channels 18, 19, 20, 21 are void , available for future use
	channels 22, 23, 24 contain the smoothed/deglinted image Tarawa-subset_Smoothed_Deglinted a spectral image in NATURAL radiances, HistEq enhancement using -E.shp shapefile, subwindow -E100/550/200/400 is not deglinted.
	channels 25, 26, 2727 contain the water column corrected reflectance Tarawa-subset_Spectral_Bottom_Reflectance A spectral image, scaled from 0 to 250. Of no interest for an image without a Blue band.
	channel_28 Tarawa-subset_Z_in_centimeters Of no interest here as depths do not exceed 15-20 m inside the lagoon. But this channel is used upon seatruthing

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