Marina jpg creating on LINUX

● (No.1190)Marina jpg creating on LINUX (2026年8月8日)
　-----------------------------------------------------

https://community.libre.space/t/observation-14707468-marina-98293/15148

> Download as satnogs.csv (2026-08-07 09:37:xx UTC)
> Take the parts starting with the string: 87 BF 54
> there are missing lines for the sequences: 19 13 00, 19 15 00, 19 16 80, 19 18 80
> there are repair parts starting with string 87 BF 94 and 87 BF D4 to replace the
> missing lines / sequences.
> (Details are under analysis.)
> right_sequence.txt
> only_payload.txt

$ cat only_payload.txt | tr -d ' ' > space_cut.txt
$ cat space_cut.txt | tr -d '\r\n' > oneline.txt
$ cat oneline.txt | xxd -r -p > marina.jpg








Marina jpg Automatic experiment (in progress)

自動的に上図赤枠の部分になるよう実験継続中。
(satnogs.csvは直近のものを使用。実験途中で各出力ファイルを多少の整形が必要｡）

----------------------------------------------------------------------------------------------
[extract1.rb] ... satnogs.csv から行頭 "87BD14" の行を抜粋

> File.open("extract1.txt", "w") do |out|
>   File.foreach("satnogs.csv") do |line|
>     out.puts line if line.include?("87BD14")
>   end
> end

$ ruby extract1.rb > 60809ma1.sh
$ sh 60809ma1.sh

----------------------------------------------------------------------------------------------
[sequence1.rb] ... 上図赤枠の部分になるよう、2行づつ "[i]80,[i]00" と並べ替え

> for i in 0..0x0f0
> printf("grep 87BD1400841B000000020D1E695119%02X extract1.txt | head -2 >> sequence1.txt\n", i)
> end

$ ruby sequence1.rb > 60809ma2.sh
$ sh 60809ma2.sh

----------------------------------------------------------------------------------------------
[reverse1.rb] ,,, その2行づつを [i]80, [i]00 → [i]00, [i]80 と上下入れ替え
                   全行[i]順を確認。特に1行目にFFD8, 最終行にFFD9の存在を確認

> lines = File.readlines("sequence1.txt")
> File.open("sequence2.txt", "w") do |file|
>   lines.each_slice(2) do |pair|
>     pair.reverse_each { |line| file.print line }
>   end
> end

$ ruby reverse1.rb > 60809ma3.sh
$ sh 60809ma3.sh

----------------------------------------------------------------------------------------------
[reverse2.rb] ... 各行の最初と最後の部分をカットし、全行の主要データ範囲を抽出

> File.open("reverse3.txt", "w") do |out|
>   File.foreach("reverse2.txt") do |line|
>     out.puts line.chomp[58, 256]
>   end
> end

$ ruby reverse2.rb > 60809ma4.sh
$ sh 60809ma4.sh

----------------------------------------------------------------------------------------------
[one_line1.txt] ... FFD8〜FFD9を一行に編集し、JPG画像化

$ tr -d '\n' < reverse3.txt > one_line1.txt
$ cat one_line1.txt | xxd -r -p > 60809mar.jpg

トップ へ戻る．
前のページ へ戻る．
次のページ へ移る．
ホームページ(目次) へ戻る．