rasterm

Encodes images to iTerm / Kitty / SIXEL (terminal) inline graphics protocols.

Supported Image Encodings

• Kitty
• iTerm2 / WezTerm
• Sixel

TODO

• mintty:
  • detection for iTerm format: https://github.com/mintty/mintty/issues/881
• iTerm2:
  • support: name, width, height, preserveAspectRatio options
• perhaps query tmux directly: TMUX=/tmp/tmux-1000/default,3218,4
• improve terminal identification 19:VT340 ESC[>0c = 19;344:0c https://invisible-island.net/xterm/ctlseqs/ctlseqs-contents.html

TESTING

• test sixel with
  • https://domterm.org/
  • https://www.macterm.net/
• test wez/iterm img with
  • iterm2
  • https://www.macterm.net/

Notes

terminal features matrix

| terminal | sixel | iTerm2 format | kitty format | | :--- | :--: | :--: | :--: | | ghostty | | | Y | | iterm2 | Y | Y | | | kitty | | | Y | | rio | Y | Y | | | mintty | Y | Y | | | mlterm | Y | Y | | | putty | | | | | rlogin | Y | Y | | | wezterm | Y | Y | | | xterm | Y | | |

known responses

CSI 0 c

| terminal | response | | :---- | :---- | | apple terminal | \x1b[?1;2c | | ghostty | \x1b[?62;22c | | guake | \x1b[?65;1;9c | | iterm2 | \x1b[?62;4c | | kitty | \x1b[?62;c | | rio | \x1b[?62;4;6;22c | | mintty | \x1b[?64;1;2;4;6;9;15;21;22;28;29c | | mlterm | \x1b[?63;1;2;3;4;7;29c | | putty | \x1b[?6c | | rlogin | \x1b[?65;1;2;3;4;6;7;8;9;15;18;21;22;29;39;42;44c | | st | \x1b[?6c | | terminology | \x1b[?64;1;9;15;18;21;22c | | vimterm | \x1b[?1;2c | | wez | \x1b[?65;4;6;18;22c | | xfce | \x1b[?65;1;9c | | xterm | \x1b[?63;1;2;4;6;9;15;22c |

CSI > 0 c

| terminal | response | | :---- | :---- | | apple terminal | \x1b[>1;95;0c | | ghostty | \x1b[>1;10;0c | | guake | \x1b[>65;5402;1c | | iterm2 | \x1b[>0;95;0c | | rio | \x1b[>0;95;0c | | kitty | \x1b[>1;4000;19c | | mintty | \x1b[>77;30104;0c | | mlterm | \x1b[>24;279;0c | | putty | \x1b[>0;136;0c | | rlogin | \x1b[>65;331;0c | | st | NO RESPONSE | | vimterm | \x1b[>0;100;0c | | wez | \x1b[>0;0;0c | | xfce | \x1b[>65;5402;1c | | xterm | \x1b[>19;344;0c |

identifications

| terminal | values | | :---- | :---- | | apple terminal | TERM_PROGRAM="Apple_Terminal" | | apple terminal | __CFBundleIdentifier="com.apple.Terminal" | | ghostty | TERM="xterm-ghostty" | | rio | TERM="rio" | | guake | | | iterm2 | LC_TERMINAL="iTerm2" | | kitty | TERM="xterm-kitty" | | mintty | TERM="mintty" | | mlterm | | | putty | | | rlogin | | | st | | | terminology | TERM_PROGRAM=terminology | | vimterm | VIM_TERMINAL is set | | wez | TERM_PROGRAM="wezterm" | | xfce | | | xterm | |

opinions

• Sixel is a primitive and wasteful format. Most sixel terminals also support the iTerm2 format--fewer bytes, full color instead of paletted, and no pixel re-processing required. Much better!

go stuff

go tool pprof -http=:8080 ./name.prof
godoc -http=:8099 -goroot="$HOME/go"
go test -v
go mod tidy
https://blog.golang.org/pprof

more reading

• kitty inline images: https://sw.kovidgoyal.net/kitty/graphics-protocol.html
• iterm2 inline images: https://iterm2.com/documentation-images.html
• xterm ctl seqs: https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
• sixel ctl seqs: https://vt100.net/docs/vt3xx-gp/chapter14.html
• libsixel: https://saitoha.github.io/libsixel/