mex_drivers — Mars Express Driver Classes¶
The ale.drivers.mex_drivers module
Added in version 0.8.1.
- class ale.drivers.mex_drivers.MexHrscIsisLabelNaifSpiceDriver(file, num_ephem=909, num_quats=909, props={})¶
Bases:
LineScanner,IsisLabel,NaifSpice,RadialDistortion,Driver- property fikid¶
Naif ID code of the filter dependent instrument codes.
Expects filter_number to be defined. This should be an integer containing the filter number from the pds3 label. Expects ikid to be defined. This should be the integer Naif ID code for the instrument.
Returns¶
- : int
Naif ID code used in calculating focal length
- property ikid¶
Returns the Naif ID code for the HRSC head instrument
This would be the Naif ID code for the base (or “head”) instrument.
Returns¶
- : int
Naif ID used to for indentifying the instrument in Spice kernels
- property line_scan_rate¶
Returns¶
- : tuple
list of lines, list of ephemeris times, and list of exposure times
- class ale.drivers.mex_drivers.MexHrscPds3NaifSpiceDriver(file, num_ephem=909, num_quats=909, props={})¶
Bases:
LineScanner,Pds3Label,NaifSpice,RadialDistortion,DriverDriver for a PDS3 Mars Express (Mex) High Resolution Stereo Camera (HRSC) images.
NOTES¶
HRSC has 9 different filters. Each has it’s own instrument id, as well as the main/”HEAD” camera composing those filters. There is also another “SRC” instrument, making-up a total of 11 distinct sensors. It is very important to understand which code is needed when/where.
HRSC is a variable line scanner, and so does not maintain one exposure duration, but rather differing exposure durations per line. This information is stored within the individual records in the image data itself, with the the first 8 bytes making up the double presicion ephemeris time that the line exposure was started, and the next 4 bytes making up the float containing that line’s exposure duration.
- property binary_ephemeris_times¶
Returns the ephemeris times taken from the binary image data.
For HRSC, the ephemeris times are imbedded in the binary data of the image. The ephemeris times start at the first byte of the line/records and are 8 bytes long.
Returns¶
- : list
Ephemeris times
- property binary_exposure_durations¶
Returns the exposure durations taken from the binary image data.
For HRSC, the exposure durations are imbedded in the binary data of the image. The expsoure durations start at the 9th byte of the line/record and are 4 bytes long.
Returns¶
- : list
Exposure durations
- property binary_lines¶
Returns the lines of the binary image data.
For example, the first entry would be the first line of the image.
Returns¶
- : list
Image lines
- property detector_center_line¶
Returns the center detector line.
For HRSC, we are dealing with a single line, so center line will be 0.
Returns¶
- : float
Detector line of the principal point
- property detector_center_sample¶
Returns the center detector sample.
For HRSC, center sample is consistent regardless of filter. This is different from ISIS’s center sample because ISIS line scan sensors use 0.5 based detector samples.
Returns¶
- : float
Detector sample of the principal point
- property ephemeris_stop_time¶
Returns the ephemeris stop time.
For HRSC, the ephemeris stop time is calculated from the binary image data.
Returns¶
- : float
Ephemeris stop time
- property fikid¶
Naif ID code of the filter dependent instrument codes.
Expects filter_number to be defined. This should be an integer containing the filter number from the pds3 label. Expects ikid to be defined. This should be the integer Naid ID code for the instrument.
Returns¶
- : int
Naif ID code used in calculating focal length
- property focal2pixel_lines¶
Expects fikid to be defined. This must be the integer Naif id code of the filter-sepcific instrument.
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
- : list<double>
focal plane to detector lines
- property focal2pixel_samples¶
Expects fikid to be defined. This must be the integer Naif id code of the filter-sepcific instrument.
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
- : list<double>
focal plane to detector samples
- property focal_length¶
Returns the focal length of the filter-specific sensor
Expects fikid to be defined. This must be the integer Naif id code of the filter-specific instrument.
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
- : float
focal length
- property ikid¶
Returns the Naif ID code for the HRSC head instrument
This would be the Naif ID code for the base (or “head”) instrument.
Returns¶
- : int
Naif ID used to for indentifying the instrument in Spice kernels
- property instrument_id¶
Returns the short name of the instrument
MEX HRSC has nine different filters each with their own name.
Returns
- property line_exposure_duration¶
Line exposure duration returns the time between the exposures for subsequent lines.
Since HRSC is a variable line scan camera, it does not make sense to have one exposure duration value.
Returns¶
- : float
Returns the line exposure duration in seconds from the PDS3 label.
- property line_scan_rate¶
Returns a 2D array of line scan rates.
For HRSC, the ephemeris times and exposure durations are stored in the image data.
In the image, every line has an entry. This method goes through and removes conescutive lines with the same exposure duration. There are also potentially missing lines in the image which this method accounts for.
Returns¶
- : list
Line scan rates
- property odtk¶
The coefficients for the distortion model
Returns¶
- : list
Radial distortion coefficients. There is only one coefficient for LROC NAC l/r
- property pixel2focal_x¶
Expects fikid to be defined. This must be the integer Naif id code of the filter-specific instrument.
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
: list<double> detector to focal plane x
- property pixel2focal_y¶
Expects fikid to be defined. This must be the integer Naif id code of the filter-specific instrument.
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
: list<double> detector to focal plane y
- read_image_data()¶
Reads data off of image and stores in binary_exposure_durations, binary_lines, and binary_ephemeris_times.
For HRSC, the exposure durations and ephemeris times are imbedded in the binary data of the image itself. Each line is stored in what is referred to as a “record” within the image. The label will have the size of each record, the number of records, and the number of records in the label, so the beginning of binary data can be calculated.
For each line/record of the binary data, the first 8 bytes make up the double presicion value of the ephemeris time, with the next 4 bytes making up the float value of the line exposure duration for the associated line. NOTE: The prefix data is always LSB, regardless of the overall file format.
- class ale.drivers.mex_drivers.MexSrcPds3NaifSpiceDriver(file, num_ephem=909, num_quats=909, props={})¶
Bases:
Framer,Pds3Label,NaifSpice,RadialDistortion,DriverDriver for a PDS3 Mars Express (Mex) High Resolution Stereo Camera (HRSC) - Super Resolution Channel (SRC) image.
- property detector_center_line¶
Returns the center detector line.
Returns¶
- : float
Detector line of the principal point
- property detector_center_sample¶
Returns the center detector sample.
This is different from ISIS’s center sample because ISIS uses 0.5-based samples.
Returns¶
- : float
Detector sample of the principal point
- property focal2pixel_lines¶
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
- : list<double>
focal plane to detector lines
- property focal2pixel_samples¶
NOTE: These values are pulled from ISIS iak kernels.
Returns¶
- : list<double>
focal plane to detector samples
- property ikid¶
Returns the Naif ID code for HRSC SRC.
Returns¶
- : int
Naif ID used to for indentifying the instrument in Spice kernels
- property instrument_id¶
Returns the short name of the instrument
MEX HRSC has nine different filters each with their own name.
Returns