Geoscan-Edelveis mission

SA2KNG · December 15, 2022, 5:51pm

There’s two updates since most fetched my tools, and this last one fixes the broken image problem when processing in single mode and using a lot of redundant data.

github.com

kng/geoscan-tools/blob/main/process_frames.py#L99


      
                  print("Raw file to: {}".format(rawfile.name))
              fileindex += 1
          pos = addr - outfile.tell()
          if pos != 0 and args.verbosity >= 1:
              print("Skipped {} bytes at pos {}. ".format(pos, addr - pos))
              # if args.pad:
              #     outfile.write(args.pad * pos)
              # pos //= 2
              # outfile.write(b'\xFF\xFF' * pos)
          outfile.seek(addr)
          if addr != 16352 or not midend:  # only write the address once, it contains zero padding
              outfile.write(bytes.fromhex(payload))
          if addr == 16352:
              midend = True
          if not rawfile.closed:
              rawfile.write(row + '\n')
          chunks += 1
          # stopping at 32736 or 16352 if not in single mode
          if not args.single and ((cmd == dataframes[2] and addr >= 16352 and args.half) or
             (cmd == dataframes[2] and addr >= 32736 and not args.half)):
              outfile.close()

SA2KNG · December 15, 2022, 10:02pm

So the bugfix resulted in a complete image from 2022-11-28 as well:
2022-11-28_good

geoscan · December 16, 2022, 5:05am

Great job! Thank you!

geoscan · December 16, 2022, 7:53am

New image transmissions (images are made 1-3 minutes before transmissions):
16.12 scheduled (UTC Time):
Image 1: 08:48:00 + 08:49:30
Image 2: 10:20:00 + 10:21:00
17.12 scheduled (UTC Time):
Image 3: 08:22:00 + 08:23:00
Image 4: 09:54:00 + 09:55:00

dereksgc · December 16, 2022, 8:29am

I do, I should have two new Bullseye LNBs ready, please let me know if there will be any tests over the weekend

geoscan · December 16, 2022, 2:20pm

Hello again! We have made a new post about image transmission on our web site! There will be another one later next year with more amateurs. Also we’ll make a post about X-band transceiver after it will be received.

And I would like to announce that we will have diploma program next year! So we will send individual diploma (only digital internationally, although handwritten) to everyone who received and decoded image from our satellite. Same with X-band transmitter.

PE0SAT · December 16, 2022, 2:37pm

The output of the following observation SatNOGS Network - Observation 6878616

geoscan · December 16, 2022, 3:10pm

la Manche? How beautiful!! Thank you!

tomasz · December 16, 2022, 9:17pm

It will be nice You have already received something your station on X-band ?

geoscan · December 17, 2022, 12:31pm

We will try next week.

geoscan · December 17, 2022, 12:32pm

@SA2KNG Have you been able to get image 1 or image 3?

SA2KNG · December 17, 2022, 2:47pm

2022-12-16 08:xx
2022-12-16_08

2022-12-17 08:xx
2022-12-17_08

geoscan · December 17, 2022, 3:01pm

Well, winter, clouds everywhere… Thank you!

SA2KNG · December 17, 2022, 3:38pm

I have’nt been able to get a complete image for the 2022-12-17 09:xx, best I could do:
bild

PE0SAT · December 17, 2022, 4:01pm

I have the same experience

geoscan · December 17, 2022, 4:50pm

Alps! Wow! I’ll try my best to recover it from cubesat
Thank you!

SA2KNG · December 17, 2022, 5:59pm

I have been looking into the actual data and it seems like the jpeg is actually smaller than the 32k ?
Like as if it’s compressed several times and lowering the quality until it fits that size.
This also results in the last bytes being the same as last image if the newer is smaller ?

My first impression was to fingerprint the images with that last frame, but if this theory is correct then another frame should be selected for something like this.

jupitersaturn09 · December 17, 2022, 10:58pm

@geoscan is it possible for you to schedule the sat so it will take images in one place, and transmit them in another?

geoscan · December 19, 2022, 1:33pm

Size of an image is not more than 32k. So what comes out depends on all details an image have.

I am thinking about a better way of an image transmission for this current mission. I believe, we will be able to update it jan-feb next year.

geoscan · December 19, 2022, 1:35pm

Yes, it is possible. We did this with New Zealand transmission on 7th december