Release Notes GAMMA Software, 20161208 · 12/8/2016 · A demo example on the updating of a DEM using Tandem-X data was added. Sentinel-1 demo example: Contents TDX_demo_Etna.tar.gz

Release Notes GAMMA Software, 20161208

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Urs Wegmüller, Charles Werner, Andreas Wiesmann, Othmar Frey, Christophe Magnard

Gamma Remote Sensing AG

Worbstrasse 225, CH-3073 Gümligen

http://www.gamma-rs.ch

8-Dec-2016

Introduction

This information is provided to users of the GAMMA software. Further distribution of this

document is restricted.

This release of the Gamma software includes new programs that provide new capability,

additional features to existing programs and bug fixes.

Gamma Software on Linux, OSX, and Windows

The Gamma software has been compiled and tested on Linux (different distributions), Apple

MacOS Sierra (10.12.1) and OSX El Capitan (10.11.6) and Windows 7, 8, and 10 (64-bit).

Computationally intensive programs such as used in co-registration and resampling and

geocoding have been parallelized using the OPENMP API built into the GCC compiler.

Processing speed on Linux, OSX, and Windows systems is comparable.

Linux Distribution:

The Gamma software is developed on Ubuntu 14.04 LTS 64-bit Linux and is tested

extensively with this distribution. Hence it is highly recommended to run the software on this

distribution.

The software has also been compiled for Ubuntu 16.4 LTS and tested.

Versions of the Software will also be uploaded for RHEL6, and RHEL7 based on Centos 6,

and 7. RHEL5 is no longer supported as some programs cannot be compiled due to outdated

gdal.

For installation instructions for the binary LINUX distributions see the ASCII file

INSTALL_linux.txt (provided with the distribution E-mail or found in the main directory of

the distribution).

Apple OSX Distribution:

The software in this version has been compiled using MacOS Sierra (10.12.1) and OSX El

Capitan (10.11.6). You will need to install libraries such as GDAL using MacPorts for your

OS version.

For installation instructions for the binary OSX distributions see the ASCII file

INSTALL_OSX_Sierra_El_Capitan.txt (provided with the distribution E-mail or found in the

main directory of the distribution).

Announcement: El Capitan will no longer be supported after the mid 2017 upgrade.


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Windows Distribution:

The Windows 7, 8, 10 version of the Gamma software is 64-bits and multi-threaded. The

software has been compiled under Win10 and will also run on Win7, and 8. The build uses the

MINGW64 GCC compilers 6.2.0. The Gamma Software is now statically linked to the

Gamma Libraries.

For installation instructions for the binary Windows distributions see the ASCII file

INSTALL_WIN64.txt (provided with the distribution E-mail or found in the main directory of

the distribution).

Documentation:

The documentation was updated:

The documentation is now more interactive and includes for each module a Contents sidebar

on the right side and a search functionality.

The program gamma_doc facilitates the access to the documentation related to a given

module or program:

gamma_doc Opens the main page of the documentation.

gamma_doc DIFF Opens the DIFF&GEO documentation.

gamma_doc az_proc Opens the reference manual page for az_proc.

Notice that there is a separate Users Guide on Sentinel-1 support (pdf file Sentinel-

1_users_guide.pdf in directory DIFF/html).

Hardware Recommendations

Using multi-core processors (4 or more cores) will bring substantial improvement in

processing speed due to parallelization of the code base. There should be at least 2 GB RAM

available for each processor core with 8 to 16 GB per core recommended.

Disk storage requirements for using the Gamma Software effectively depend on the amount of

input data and data products that will be produced. Based on our experience we recommend to

consider at least 4 TB space, especially when working with stacks of Sentinel-1 or very high

resolution data (TerraSAR-X, Cosmo-Skymed) data. The current trend towards larger data

products requires substantially increased storage capacities.

GAMMA Software Training Courses

GAMMA plans to organize in spring 2017 again training courses at GAMMA (near Bern,

Switzerland) for SAR/INSAR (MSP/ISP/DIFF&GEO/LAT) and for PSI (IPTA). See also our

web-site under http://www.gamma-rs.ch/courses/training-courses.html.


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Significant Changes in the Gamma Software Modules since the Mid - 2016 release

Supporting Sentinel-1 EWS SLC

In this period the Sentinel-1 programs and scripts were updated to also support Sentinel-1

Extra Wide Swath (EWS) SLC data (that have become occasionally available). As IWS data

EWS acquisitions are in TOPS mode, but with 5 instead of 3 sub-swaths. With this update

EWS SLC data can be used also for interferometry, offset tracking, SBI, and PSI.

S1 RFI filtering

Radio-Frequency Interference (RFI) filtering can be applied to Sentinel-1 SLC data. The

methodology is documented in one of the new Gamma Software Demo examples (see below).

Reference for Sentinel-1 Support in the GAMMA Software

A reference for Sentinel-1 Support in the GAMMA Software became available now in an on-

line journal:

Wegmüller U., C. Werner, T. Strozzi, A. Wiesmann, O. Frey and M. Santoro, “Sentinel-1

Support in the GAMMA Software”, Procedia Computer Science, 100: 1305-1312, 2016,

doi:10.1016/j.procs.2016.09.246. (access link: http://dx.doi.org/10.1016/j.procs.2016.09.246)

Gamma Software Demo examples

In this period new Gamma Software Demo examples were added:

- demonstrating SAR processing with MSP

- demonstrating the application of InSAR, offset tracking, SBI, PSI for Sentinel-1

- demonstrating IPTA processing

- demonstrating the generation of a DEM update using Tandem-X data

Gamma Software Users with a valid license or evaluation license can download the Gamma

Software Demo examples here:

account: http://www.gamma-rs.ch/userdata/Gamma_Software_demo

user: gamma_user

password: RBS_821

Gamma Software Demo examples for the MSP

New demo examples were added for the MSP. Now that internet access is normally much

faster than in the past we added MSP demo examples showing raw data processing for full

frames. Furthermore, the data are provided in the current formats used by the Agencies.

MSP demo example: Contents

Gamma_demo_MSP_ASAR.tar.gz ENVISAT ASAR IS2 VV-pol., full frame

Gamma_demo_MSP_CS.tar.gz Cosmo-Skymed HDF5 format, stripmap-mode, left-

looking

Gamma_demo_MSP_ERS2_zero-gyro.tar.gz ERS-2 Zero-Gyro mode (4 data sets with different large

Doppler Centroids)

Gamma_demo_MSP_ERS.tar.gz ERS-1 VV-pol., full frame

Gamma_demo_MSP_JERS.tar.gz JERS-1 HH-pol., full frame

Gamma_demo_MSP_PALSAR1.tar.gz PALSAR-1 HH-pol., full frame, FBS

MSP_users_guide_examples.tar.gz Examples from MSP users guide (ASAR, ERS, JERS,

PALSAR, RADARSAT, SIRC), reduced size raw data sets

http://dx.doi.org/10.1016/j.procs.2016.09.246

http://www.gamma-rs.ch/userdata/Gamma_Software_demo


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Gamma Software Demo examples for Sentinel-1

New demo examples were added to demonstrate the application of a range of techniques

(InSAR, offset tracking, SBI, PSI for Sentinel-1) for Sentinel-1 TOPS mode data.

Sentinel-1 demo example: Contents

S1_Mexico_INSAR_demo.tar.gz Sentinel-1A DInSAR (co-registration, differential

interferogram) for a pair over Mexico showing significant

deformation.

Data consist of 2 sub-swaths with 2 bursts each.

S1A_S1B_DINSAR_ItalyEarthquake_demo.tar.gz Sentinel-1A - Sentinel-1B DInSAR (co-registration

differential interferogram, unwrapping) for co-seismic pair.

Data consist of 2 sub-swaths with 3 and 2 bursts.

S1_Greenland_tracking_demo.tar.gz Sentinel-1A offset tracking (co-registration, differential

interferogram offset tracking, post-processing of offset

field, geocoding of result).

Data consist of 2 sub-swaths with 2 bursts each.

S1_DevonIceCap_demo.tar.gz Sentinel-1A offset tracking and split-beam interferometry

(co-registration, differential interferogram, split-beam

interferogram, offset tracking).

Data consist of 2 sub-swaths

S1_Magdeburg_multitemp_demo.tar.gz Demonstration of multi-temporal filtering of Sentinel-1

data.

Processing starts from 24 co-registered SLC mosaics at VV

and VH Pol.

S1_RFI_filtering.tar.gz Demonstration of Radio Frequency Interference (RFI)

filtering of a Sentinel-1 IWS SLC.

Data consist of 1 sub-swaths with 3 bursts.

IPTA_S1_Athens_demo.tar.gz (see directory

Gamma_demo_IPTA for this example)

IPTA processing for Sentienl-1 data. Single and multi-look

phases are considered. A multi-reference stack method is

used.

Processing starts from co-registered SLC stack.

In the following some of the results of the demo examples are shown.

S1 DInSAR over Mexico City: geocoded differential

interferogram (see S1_Mexico_INSAR_demo).

S1 DInSAR over Mexico City: geocoded RGB

coherence product (R: coherence, G: backscatter, B:

backscatter change) (see S1_Mexico_INSAR_demo).


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S1A-S1B geocoded co-seismic differential

interferogram for magnitude 6.2 Earthquake of 24

August 2016 in Central Italy

Sentinel-1A IPTA demo result over site near Athens

that includes small areas with fast, potentially non-

uniform, motion (average deformation rate is shown).

S1 IWS range offset field over site in Greenland.

S1 IWS azimuth offset field over site in Greenland.

S1 split-beam interferometry phase,

20150117_20150129, over Devon Island, indicating

significant ionospheric effects.

S1 azimuth offset field, 20150117_20150129, over

Devon Island, indicating significant ionospheric effects.


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S1 RGB composite of unfiltered VV backscatter (red),

VH backscatter (green) and VV/VH ratio (blue), on

20150813, over area near Magdeburg.

S1 RGB composite of temporally filtered VV

backscatter (red), VH backscatter (green) and VV/VH

ratio (blue), on 20150813, over area near Magdeburg.

S1 VH-pol. backscatter on 20160905 over a small

section of the Swiss Alps, with RFI anomalies visible.

S1 VH-pol. backscatter on 20160905 over a small

section of the Swiss Alps; RFI filtering permitted

removing the RFI anomalies.


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Gamma Software Demo examples for IPTA processing

New demo examples were added to demonstrate different time series analysis approaches

supported by the IPTA module.


IPTA_demo_ERS_Borth.tar.gz ERS IPTA process for area with > 5cm/year deformation rates,

starting with multi-reference stack. Then after that two alternative

approaches are used to continue. In the first approach the point

heights determined with the multi-reference stack are used in a

subsequent single reference stack regression. In the second approach

the mb_pt is used to generate the time series.

Data consist of stack of co-registered SLC sections.

IPTA_demo_PALSAR_Chiba.tar.gz PALSAR-1 IPTA processing over an urban area with high

deformation rates. Initially a multi-reference stack is used.

Data consists of stack of co-registered SLC sections.

IPTA_S1_Athens_demo.tar.gz IPTA processing example using S1 data over a small section to the

West of Athens. The site includes small areas with fast, potentially

non-uniform, motion (related to the compaction of landfills).

Example demonstrates IPTA processing for S1 data. Example

demonstrates the combined use of single-pixel and multi-look

phases. Example demonstrates the use of a multi-reference stack to

map fast non-uniform motion and to optimize the spatial coverage

achieved.

Example demonstrates alternative approaches to separate phase

related to deformation and atmospheric path delay.

Data consists of stack of co-registered SLC sections.


ERS IPTA example over Borth, Germany. The average

deformation rate is shown using a color scale between -

7.5cm/year (red) and +7.5cm/year (blue).

PALSAR-1 IPTA example over Chiba, Japan. The

average deformation rate is shown using a color scale

between -2.5cm/year (red) and +2.5cm/year (blue).


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Gamma Software Demo examples for DEM generation using Tandem-X data.

A demo example on the updating of a DEM using Tandem-X data was added.


TDX_demo_Etna.tar.gz Updating of a DEM using Tandem-X data. In some areas the DEM

update is > 20m, so that the height difference need to be considered

in the geocoding.


SRTM DEM height over Etna Volcano, visualized with

color scale and shaded relief.

Updated, Tandem-X based DEM height over Etna

Volcano, visualized with color scale and shaded relief.

MSP

MSP Documentation update: the documentation is now more interactive and includes a

Contents sidebar on the right side (it replaces MSP_documentation.html,

MSP_reference_manual.html, and MSP_users_guide.html. An easy way to access the MSP

documentation is to use the command gamma_doc MSP .

MSP demo examples update (see also above): New demo examples were added for the MSP,

providing now full frames of raw data and using the current formats used by the Agencies

(e.g. ERS data in ENVISAT format).


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ISP

ISP Documentation update: the documentation is now more interactive and includes a

Contents sidebar on the right side (it replaces ISP_documentation.html, ISP_reference_

manual.html, and ISP_users_guide.html. An easy way to access the ISP documentation is to

use the command gamma_doc ISP .

multi_S1_TOPS, SLC_mosaic_S1_TOPS: Write out date string in the image parameter file

using YYYY MM DD format (instead of the HH MM SS.SSSSS data fields that might be

present in the input date string).

OPOD_vec: Updated to support adding OPOD state vectors for both S1A and S1B. The

program determines now the sensor (S1A or S1B, based on the SLC parameter file sensor

parameter) and selects then for this sensor the correct OPOD file and extracts the OPOD state

vectors.

ISP_lib: Added support for the calculation of the burst parameters for Sentinel-1 EWS SLC

data.

image_stat: Corrected calculation of standard deviation of the data (previous value was the

variance).

multi_look: Correction in the calculation of the starting azimuth angle and angle increment of

GPRI-2 multi-look images.

typedef_ISP.h: Added a data type VEC_ENU (vector with East,North,Up coordinates) to be

used for earth surface vectors.

unw_correction_filt: Added a new script supporting phase unwrapping ambiguity error

correction. The deviation relative to a spatially filtered phase image is used to identify and

correct local unwrapping ambiguity errors.

unw_correction_poly: Added a new script supporting phase unwrapping ambiguity error

correction. An area with an ambiguity error is marked by the operator with a polygon (drawn

using polyras). The polygon drawn should include the entire area to correct and a small

margin around it with unwrapped phases on the correct ambiguity. Based on the statistics of

the polygon area a threshold is determined and used to correct the ambiguity error.

mcf: Modified to set the reference point phase not to 0.0 (no-data) but rather to 1.18e-38

(smallest floating point number) when using init_flag=1. In this mode the phase of the

reference point is subtracted from the entire scene.

DIFF&GEO

DIFF&GEO Documentation update: the documentation is now more interactive and includes

a Contents sidebar on the right side (it replaces DIFF_documentation.html,

DIFF_reference_manual.html, and DIFF_users_guide.html. An easy way to access the

DIFF&GEO documentation is to use the command gamma_doc DIFF .

datums.h: The Swiss 3-PAR datum shift parameters were changed to the current 3-PAR

datum shift parameters provided by Swisstopo. Similarly the Swiss 7-PAR datum

transformation parameters were changed to GRANIT 7-PAR datum transformation

parameters as provided by Swisstopo.


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sub_phase: An option was added to operate the program with SCOMPLEX data as well as

with FCOMPLEX and FLOAT (to support e.g. the subtraction of the azimuth phase ramp in

the deramping of SLC data from Sentinel-1 IWS or spotlight-mode SAR images).

vrt2dem_latlon: A new script vrt2dem_latlon was added to extract a region from a virtual

DEM (VRT DEM) in geographic coordinates as specfied by latitude and longitude bounds.

For the selected area the VRT DEM is converted to GAMMA DEM with the associated

DEM_par file. The functionality is similar to vrt2dem but the DEM section is directly

specified on the command line instead of calculated based on a MLI_par file.

srtm2dem, vrt2dem, vrt2dem_latlon: Modified to support the following modes (gflg) of

operation are possible:

0: no geoid offset correction, replace NODATA with 1.e-20.

1: add constant geoid offset to get WGS84 referenced heights, NODATA are set to the

offset value

2: add interpolated geoid offset to get WGS84 referenced heights no-data are set to the

interpolated geoid offset

3: no geoid offset correction, replace NODATA with 0.0

The most important difference with prior versions is that the geoid offset correction is also

applied to regions of NODATA. This is to allow regions of ocean to be covered. It is also

possible to write out the geoid resampled to the DEM grid.

S1_coreg_TOPS, S1_coreg_TOPS_no_refinement: Corrected for use with a constant height

value (entered on the command line) rather than a DEM resampled into range-doppler

coordinates.

lk_vec_lt: Added new program to calculate the look vector (defined as pointing from the pixel

location to the sensor) in ENU (East,North,Up) coordinates basis as well as the look vector

angles (same as calculated using the program look_vector) from the lookup table.

base_calc: Added check if there are state vectors available in the SLC parameter files. If not,

then set baselines to 0.0. This modification is useful for the generation of an itab for GPRI

measurement network based on time intervals alone.

S1_poly_overlap: Updated to support Sentinel-1 Extended Wide Swath (EWS) data (with 5

sub-swaths).

S1_coreg_TOPS, S1_coreg_TOPS_no_refinement: Updated to support Sentinel-1 Extended

Wide Swath (EWS) data (with 5 sub-swaths). Updated Sentinel-1 Users guide to include

processing EWS data.

S1_deramp_TOPS_reference, S1_deramp_TOPS_slave: Updated to support Sentinel-1

Extended Wide Swath (EWS) data (with 5 sub-swaths).

quad_fit: Added phase model 6: a0 + a1*y + a5*y^2

condition_offset_estimates: Added script to post-process an offset field (as generated using

offset_pwr_tracking or offset_pwr_trackingm). Besides applying a threshold on the offset

estimation quality thresholds concerning the valid absolute range and azimuth offset intervals

and valid relative range and azimuth offset intervals (relative to a spatially filtered solution)

are used to remove unreliable estimates and outliers from an offset field.


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DISP

DISP Documentation update: the documentation is now more interactive and includes a

Contents sidebar on the right side (it replaces DISP_documentation.html and

ISP_reference_manual.html. An easy way to access the ISP documentation is to use the

command gamma_doc DISP .

vec_to_real: Added program to extract components from a vector data file and store as float

real values. Vector data are triplets of 4-byte single-precision floating point numbers in an

orthogonal basis such as XYZ, ENU, SCH.

float_math: Added trignometric functions sin, cos, tan, asin, acos, atan2.

rasmph_pwr24, dismph_pwr24: modified to display 0.0 phase as cyan rather than as

grayscale.

LAT

LAT Documentation update: the documentation is now more interactive and includes a

Contents sidebar on the right side (it replaces LAT_documentation.html,

LAT_reference_manual.html, and LAT_users_guide.html. An easy way to access the LAT

documentation is to use the command gamma_doc LAT .

histogram: Added extra field in the output to include also the sum of the data in each polygon.

multi_class_mapping: Supports now writing of output image in TIFF format.

MLI_despiking: A new script to determine and remove spikes in an MLI was added. This

script is used also as part of the new script AMI_FILTER .

AMI_FILTER: A new script supporting Advanced Multi Image Filtering of co-registered MLI

stacks (can be in SAR or map geometry) was added.

IPTA

IPTA Documentation update: the documentation is now more interactive and includes a

Contents sidebar on the right side (it replaces IPTA_documentation.html,

IPTA_reference_manual.html, and IPTA_users_guide.html. An easy way to access the IPTA

documentation is to use the command gamma_doc IPTA .

pt2geo: The optional output plat_lon was changed from local reference frame to WGS84

coordinates. Furthermore, and additional optional output for the WGS84 point heights was

added.

IPTA demo examples update (see also above): An example to demonstrate IPTA processing

for S1 data was added. The example also demonstrates the combined use of single-pixel and

multi-look phases and the use of a multi-reference stack to map fast non-uniform motion and

to optimize the spatial coverage achieved.

Documents

Release Notes GAMMA Software, 20161208 · 12/8/2016 · A demo example on the updating of a DEM using Tandem-X data was added. Sentinel-1 demo example: Contents TDX_demo_Etna.tar.gz