Receive Data Cube Data

Mattia Rossi

Import Libraries

library(CubeR)
library(tibble)
library(magrittr)
library(raster)

Assess the complete history (all timeStamps) of one single pixel with the pixel_history function. If plot is TRUE the response is plotted otherwise the function will return a dataframe. One or multiple dates can be added allowing to subset the request temporally.

ptm<-proc.time()
coverage<-getCapability()[11]
coord_sys<-coverage_get_coordsys(coverage = coverage)
bands<-coverage_get_bands(coverage = coverage)

subset<-c("620812.02", "5171499.36")

pxl_hst_5 <- suppressMessages(pixel_history(coverage, coord_sys, bands, subset, date = NULL,plot=F))
pxl_hst_5 <- pxl_hst_5 %>% as.tibble
## Warning: `as.tibble()` is deprecated, use `as_tibble()` (but mind the new semantics).
## This warning is displayed once per session.
## # A tibble: 171 x 7
##    Date         AOT   B02   B03   B04   B08   WVP
##    <date>     <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
##  1 2015-06-27   213   926  1061   946  2825   721
##  2 2015-07-04   213   660  1159  1375  3707  1205
##  3 2015-07-24   307   378   853   605  5419  1956
##  4 2015-08-03   148   252   696   245  6240   913
##  5 2015-08-06   159   256   632   284  5882  1508
##  6 2015-08-13   148   190   636   307  6147  1357
##  7 2015-08-16   201  8907  8005  7026  8111   568
##  8 2015-08-23   201  9438  9039  8783  8949   510
##  9 2015-08-26   136   235   623   281  5625  1034
## 10 2015-09-02   201  8569  8135  7654  8064   342
## # ... with 161 more rows

The function geocoded_pixel_buffer() adds a buffer (in Pixel) around a central Pixel. The outputs are either (i) a List containing the Request (main URL+ WCPS request), the bounding box, the timestamps and the Values per layer or (ii) a plot of the “Pixel Chips” from each timestamp requested.

ptm<-proc.time()
coverage<-getCapability()[11]
bands<-coverage_get_bands(coverage = coverage)

subset<-c("620812.02", "5171499.36")

pxl_hst_5 <- suppressMessages(geocoded_pixel_buffer(coverage, band=bands[5], coords=subset,buffer=1000, date = NULL,plot = F))
str(pxl_hst_5)
## List of 4
##  $ Request   : chr "http://10.8.244.147:8080/rasdaman/ows?SERVICE=WCS&VERSION=2.0.1&REQUEST=ProcessCoverages&QUERY=for%20c%20in%20%"| __truncated__
##  $ BB        : num [1:4] 619812 621812 5170499 5172499
##  $ TimeStamps: Date[1:171], format: "2015-06-27" "2015-07-04" ...
##  $ Values    : int [1:171, 1:201, 1:201] 4084 3336 3703 2959 3007 2980 8874 7940 2986 8029 ...
pxl_hst_5 <- suppressMessages(geocoded_pixel_buffer(coverage, band=bands[5], coords=subset,buffer=1000, date = NULL,plot = T))

passed2<-proc.time()-ptm

CubeRs’ image_from_coverage() function allows to extract a TIFF File from the Coverages. It offers paramters addressing the images in ways of selected bands, temporal acquisitions or spatial subsetting. Furthermore the res_eff parameter adds a possibility to resample the image.

ptm<-proc.time()
coverage<-getCapability()[11]
times <- coverage_get_timestamps(coverage = coverage)

coords<-c("620812.02", "5171499.36") %>% as.numeric
slice_E <- as.character(c(coords[1]-5000, coords[1]+5000))
slice_N <- as.character(c(coords[2]-5000, coords[2]+5000))

img <- image_from_coverage(coverage=coverage, slice_E, slice_N, times[1], bands = bands[4])
img[[1]]
## class      : RasterLayer 
## dimensions : 1001, 1001, 1002001  (nrow, ncol, ncell)
## resolution : 9.99001, 9.99001  (x, y)
## extent     : 615812, 625812, 5166499, 5176499  (xmin, xmax, ymin, ymax)
## crs        : +init=epsg:32632 +proj=utm +zone=32 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
## source     : memory
## names      : layer 
## values     : 13, 10930  (min, max)

Processing Time For the Single Functions:

print(paste("Time Elapsed Pixel History:",passed1[3]))
## [1] "Time Elapsed Pixel History: 19.81"
print(paste("Time Elapsed Pixel Buffer:",passed2[3]))
## [1] "Time Elapsed Pixel Buffer: 174.95"
print(paste("Time Elapsed Image:",passed3[3]))
## [1] "Time Elapsed Image: 3.35000000000002"