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First Earth Observation images compressed by the new FAPEC-CILLIC algorithm onboard ESA’s OPS-SAT

The European Space Agency (ESA) launched OPS-SAT on 18 December 2019 into a circular, polar orbit at 515 km altitude.
OPS-SAT is a technology demonstration nanosatellite based on the cubesat standard. The satellite is only 30cm x 10cm x 10cm, but it brings powerful technology and instrumentation onboard, such as a fine Attitude Determination Control System, a GPS receiver, an X-band transmitter (up to 50 Mbps downlink) or a Software Defined Radio front-end.
It also includes a high-performance data processing platform (based on a dual-core ARM Cortex-A9 processor) and a high-resolution camera (based on an RGB Bayer filter) with a bit depth of 12 bits per pixel and a ground resolution of up to 80m x 80m per pixel.

When preparing for this mission, ESA issued a call for experimenters willing to test their technologies in orbit. One of the submitted (and accepted) experiments is the FAPEC data compression software – a versatile and efficient solution for lossless and lossy compression of images and of a large variety of instrumental data.
FAPEC is already being used by a satellite constellation to compress payload data onboard. However, its image compression capabilities had not been demonstrated in orbit yet. Furthermore, FAPEC was recently improved with a new image decorrelation algorithm (named CILLIC), presented at the ESA/CNES On-Board Payload Data Compression workshop (OBPDC) on 22 September 2020. FAPEC, with its CILLIC configuration, offers lossless and lossy image compression performances similar to those achieved by wavelet transforms but at a fraction of their computational cost.

On 28 November 2020, FAPEC was uploaded to OPS-SAT. The day after, and for the very first time in orbit, it was invoked by the payload data processing system to compress two images of our planet taken from Space.
Each of the two images, with a resolution of 4 Mpix and weighting 7.6 MB, were reduced to nearly 800 KB in about 0.8 seconds in a single computing thread.
Once received on ground, they were “de-bayered” with the ImageJ software to obtain the original colour images, which are shown below.

First FAPEC-compressed images from ESA’s OPS-SAT. The colour pictures shown here have been obtained by applying a standard de-bayer algorithm on ground, without any colour correction or white balancing in this case.
Photos: ESA/OPS-SAT

 

Shortly after this, more images were acquired and, again, compressed with FAPEC to be later downlinked to the ground station. These ones better illustrate the high resolution of the camera:

Some of the Earth Observation images acquired by ESA’s OPS-SAT and compressed by FAPEC onboard. In this case, some colour correction (white balancing) was applied.
Photos: ESA/OPS-SAT

 

With this, FAPEC has been the first user non-ESA experiment to be activated onboard OPS-SAT, achieving two important goals. First, it demonstrates the feasibility of uploading and activating new experiments onboard this technology demonstration mission. And second, thanks to the efficient collaboration with ESA and OPS-SAT experts, it can provide an interesting data compression service to other experimenters having to download many images from the satellite.

FAPEC is an excellent data compression solution especially for cubesat-based missions, which use to have strong limitations in onboard computing capabilities and in the downlink. The highly optimized, versatile and portable FAPEC software allows for an agile integration in the payload data handling system while offering a compression throughput comparable to hardware-based solutions. Even satellites with just a low-range onboard computer can use it. Science return of EO missions can significantly be increased in this way.

More information:

Disclaimer: The view expressed herein can in no way be taken to reflect the official opinion of the European Space Agency.

Gaia EDR3 bulk catalogue available in FAPEC format

The Gaia group at the University of Barcelona (IEECICCUB), in cooperation with DAPCOM, has published an alternative copy of the bulk data files from Gaia EDR3 – the Early Data Release 3 from Gaia.

Gaia EDR3 was published yesterday, 3rd December 2020. Besides the on-line catalogue, bulk CSV files were also made available for download – an interesting option for exhaustive analyses. Such files are officially offered in “csv.gz” format, that is, compressed with the widely known gzip compressor.

On 6 February 2019, we released FAPEC Archiver 19.0, our professional data compression software offering high compression ratios at high speeds. One of the options provided is the compression of tabular (CSV-like) text files, such as those from the bulk Gaia EDR3. As a service to the worldwide astronomical community, and also as a demonstration of the capabilities of FAPEC, DAPCOM and the Gaia IEEC/ICCUB Group converted the GaiaSource files from the official Gaia EDR3 bulk CSV repository into the FAPEC format, reducing the total size from 613 GB to 495 GB – that is, 19% smaller than with gzip. Other data compressors like bzip2, rar, Zstandard or 7-zip cannot reach this mark.

You can now download Gaia EDR3 in csv.fapec format here:

     Gaia EDR3 csv.fapec bulk download

The additional tables available in the bulk Gaia EDR3 catalogue will also be converted and published during the coming days.

Free FAPEC decompression licenses can be obtained from our website. Besides, we are preparing a new FAPEC release, including a freely downloadable decompressor with Python bindings.

Have fun!

Spire Global uses FAPEC technology

During the past few months, DAPCOM has worked with Spire to adapt its FAPEC data compression technology to their Radio Occultation (RO) satellite data. Our software engineers and data compression experts have crafted a data compression software tool to be deployed in Spire’s payloads on-orbit, achieving a remarkably high compression ratio on RO data. DAPCOM solution will contribute to obtaining a richer data product from the satellites.

This is a strategic project for DAPCOM Data Services that consolidates the company activity in the nanosatellite industry, demonstrating the maturity and applicability of our high-performance data compression technology and its added value to space communications systems, as well as the software engineering excellence of the technical team to design and implement tailored interfaces.

Spire Global, Inc. is an American private company specializing in data gathered from a network of small satellites. It has successfully deployed several Earth observation CubeSats into Low Earth Orbit. The company has offices in San Francisco, Glasgow, Singapore, and Boulder.

FAPEC 2016.0 release

FAPEC in the UPC-BarcelonaTech 3CAT-2 CubeSat

On-board Payload Data Compression Workshop (OBPDC)

DAPCOM has participated in the On-Board Payload Data Compression workshop (OBPDC) held in Venice last October 23rd + 24th. As usual, this fourth edition was very interesting and fruitful, as can be seen in the Programme.

DAPCOM presented the results obtained with FAPEC and DWTFAPEC on a variety of test images. Most remarkably, we presented there our new developments. On one hand, a parallel implementation of our FAPEC data compressor, which scales very good up to 16 processes, reaching 600MB/s in that case. On the other hand, our new image compression algorithm, HPA (Hierarchical Pixel Averaging); despite of being just a prototype, this lossless and fixed-quality lossy compressor offers ratio-versus-quality results comparable to those of the current space standard (CCSDS 122.0), and also comparable to those obtained with the JPEG standard. The proceedings of these presentations are also available under request.

DAPCOM – ESA Business Incubation

DAPCOM Data Services has been one of the companies selected to benefit from the ESA Business Incubation programme due to the potential of its space technology (FAPEC) to be transferred from space sector to terrestrial applications. The incubation program will allow DAPCOM to continue its R&D activities on data compression techniques for multiple terrestrial applications which will reinforce the company as a reference in data compression technologies and techniques. The incubation will have a duration of two years and the company will be incubated in the RDIT building of Polytechnic University of Catalonia (UPC), located on the Baix Llobregat Campus (Barcelona).