Per-Cube Histogram

skinparam style strictuml hide footbox title Per-Cube Histogram workflow actor User box "Client-side" #EDEDED participant Frontend end box box "Server-side" #lightblue participant Backend end box User -> Frontend: Open image activate Frontend Frontend -> Backend : 1. OPEN_FILE activate Backend Frontend <-- Backend : 2. OPEN_FILE_ACK Frontend -> Backend : 3. ADD_REQUIRED_TILES Frontend -> Backend : 4. SET_CURSOR Frontend <-- Backend : 5. REGION_HISTOGRAM_DATA Frontend <-- Backend : 5. SPATIAL_PROFILE_DATA Frontend <-- Backend : 5. RASTER_TILE_DATA deactivate Backend User <-- Frontend: Displays image deactivate Frontend User -> Frontend: Request per-cube histogram activate Frontend Frontend -> Backend : 6. SET_HISTOGRAM_REQUIREMENTS (channel=-2) activate Backend loop Progress updates Frontend <--[#red] Backend : <font color="red">7. REGION_HISTOGRAM_DATA (progress < 1) [Check 1]</font> end Frontend <--[#red] Backend : <font color="red">8. REGION_HISTOGRAM_DATA (progress=1) [Check 2]</font> deactivate Backend User <-- Frontend: Displays per-cube histogram deactivate Frontend

PER_CUBE_HISTOGRAM

See the source code.

This test verifies per-cube histogram calculation on a 3D FITS image cube.

  1. Frontend sends: OPEN_FILE (OpenFile)

    directory = "set_QA"
file = "supermosaic.10.fits"
hdu = "0"
file_id = 0
render_mode = RASTER

  2. Backend returns: OPEN_FILE_ACK (OpenFileAck) and REGION_HISTOGRAM_DATA

  3. Frontend sends: ADD_REQUIRED_TILES and SET_CURSOR at (1, 1)

  4. Frontend sends: SET_HISTOGRAM_REQUIREMENTS (SetHistogramRequirements)

    file_id = 0
region_id = -2
histograms = [{channel: -2, num_bins: -1}]

  5. Backend streams: REGION_HISTOGRAM_DATA with progress updates

Check 1: at progress > 0.5, the REGION_HISTOGRAM_DATA should satisfy:

  • binWidth = 0.7235205769538879 (4 decimal precision)

  • bins.length = 2775

  • firstBinCenter = -1773.2998046875

  • channel = -2, regionId = -2

Check 2: at progress = 1.0 (complete), the REGION_HISTOGRAM_DATA should satisfy:

  • bins[2500] = 9359604

  • mean = 18.742310255027036

  • stdDev = 22.534721826342878

  • numBins = 2775

PER_CUBE_HISTOGRAM_HDF5

See the source code.

This test verifies per-cube histogram calculation on an HDF5 image cube with the same data as the FITS test.

  1. Frontend sends: OPEN_FILE (OpenFile)

    directory = "set_QA"
file = "supermosaic.10.hdf5"
hdu = "0"
file_id = 0
render_mode = RASTER

2-4. Same cursor, tiles, and histogram requirements as PER_CUBE_HISTOGRAM

Check 1: at progress = 1.0 (complete), the REGION_HISTOGRAM_DATA should satisfy:

  • binWidth = 0.7235205573004645 (4 decimal precision)

  • bins.length = 2775

  • bins[2500] = 9359604

  • firstBinCenter = -1773.2998608150997

  • numBins = 2775

  • mean = 18.742310241547514 (4 decimal precision)

  • stdDev = 22.534722680160574 (4 decimal precision)

  • regionId = -2, channel = -2

PER_CUBE_HISTOGRAM_CANCELLATION

See the source code.

This test verifies histogram computation cancellation and resumption behavior.

  1. Frontend sends: OPEN_FILE (OpenFile)

    directory = "set_QA"
file = "SDC335.579-0.292.spw0-channel-cutted.line.fits"
hdu = "0"
file_id = 0
render_mode = RASTER

  2. Frontend sends: SET_HISTOGRAM_REQUIREMENTS (SetHistogramRequirements)

    file_id = 0
region_id = -2
histograms = [{channel: -2, num_bins: -1}]

  3. Backend streams: REGION_HISTOGRAM_DATA with progress > 0

  4. After 5 seconds, Frontend cancels by sending: SET_HISTOGRAM_REQUIREMENTS with empty histograms

    file_id = 0
region_id = -2
histograms = []

  5. Backend returns: ERROR_DATA (2 error messages)

Check 1: the cancellation should satisfy:

  • Initial progress > 0 (computation started)

  • ERROR_DATA received after cancellation

  1. After 2-second wait, Frontend retries: SET_HISTOGRAM_REQUIREMENTS with original parameters

Check 2: the resumed computation should satisfy:

  • Final progress = 1.0

  • binWidth = 0.0007966686389409006

  • bins.length = 342

  • bins[170] = 10548

  • firstBinCenter = -0.09137402474880219

  • numBins = 342

  • mean = 0.00005560920907762894

  • stdDev = 0.012523454128847715