CR30 ti3 Dispensary

Python script to convert CHNSpec CR30 ColorQC 2 CSVs + ArgyllCMS TI2 into a TI3, and optionally build an ICC with ArgyllCMS colprof. Developed for the user "Pharmacist" of Printerknowledge.com and generally adaptable.

Requirements

• Python 3.x (no external Python packages required)
• ArgyllCMS installed and colprof on your PATH — only needed if [colprof].run = true.
  • If you only need a TI3, set [colprof].run = false in src/profile_config.ini.

How it works (policy)

• Pass-through: spectral, XYZ, and/or Lab from the CSV are written as-is (no conversions).
• Strict pairing: CSV row N maps to TI2 SAMPLE_ID N (by index). No re-ordering.
• SAMPLE_LOC: copied from TI2 when present; if absent but TI2 headers define layout (STEPS_IN_PASS, PASSES_IN_STRIPS2, INDEX_ORDER), it is generated deterministically; otherwise omitted (no grid inference fallback).
• PCS columns and COLOR_REP:
  • We include only the PCS columns present in your CSV. If XYZ is present we write XYZ; else if Lab is present we write Lab; else (spectral-only) we write just spectral.
  • COLOR_REP reflects the PCS columns, not spectral presence. Example: iRGB_XYZ if XYZ present; iRGB_LAB if only Lab present; spectral-only defaults to iRGB_XYZ for compatibility.
• Spectral precedence: if spectral is present in the TI3, colprof will use it for the profile fit with the configured illuminant/observer. PCS columns remain for auditing.
  • To make colprof ignore spectral, omit spectral columns from the CSV.

Quick start

1. Put inputs in src/input/
   • CSV (CR30 export)
   • TI2 (e.g., 228-target.ti2)
2. Edit src/profile_config.ini
   • Set [inputs].csv and [inputs].ti2
   • Optionally adjust [colprof] (quality, gamut mapping, viewing conditions, etc.)
3. Run the script

# Linux/macOS
python3 src/build_profile.py

# Windows
python src\build_profile.py
# or
python3 src\build_profile.py
# or python launcher
py -3 src\build_profile.py

Outputs (by default) in src/output/:

• TI3: [outputs].ti3
• ICC: [outputs].icc (when [colprof].run = true)

Tip: If you reference a source ICC for gamut mapping (e.g., AdobeRGB1998.icc via [colprof].gamut_map_both or [colprof].gamut_map_perceptual), place it in src/input/ or use an absolute path.

Files & folders

• src/input/ — your inputs (CSV, TI2, source ICCs)
• src/output/ — generated TI3 and ICC
• src/profile_config.ini — edit to control inputs/outputs and colprof options
• src/build_profile.py — single entrypoint that converts and optionally builds the ICC

Config reference (high level)

See src/profile_config.ini — each option includes comments and maps to colprof flags. Paths:

• Bare filenames under [inputs] resolve to src/input/
• Bare filenames under [outputs] write to src/output/
• Paths with directories are resolved relative to the workspace root

Sections and notable options:

• [inputs] csv, ti2
• [outputs] ti3, icc, description
• [options] device_class
• [colprof]
  • Profile quality (quality → -q), B2A detail (b2a → -b)
  • Illuminant/observer (illuminant/observer → -i/-o) — used only if TI3 has spectral
  • Algorithm/dark emphasis/avg dev (-a, -V, -r)
  • FWA (fwa/fwa_illuminant → -f and FWA illuminant) — requires spectral
  • Gamut mapping (gamut_map_perceptual → -s, gamut_map_both → -S, source_gamut_file → -g, abstract_profiles → -p)
  • Intents (perceptual_intent → -t, saturation_intent → -T)
  • Viewing conditions (viewcond_in/viewcond_out → -c/-d)
  • Diagnostics/identity (-P, manufacturer/model/copyright → -A/-M/-C)
  • Attributes/default intent (attributes/default_intent → -Z)
  • Ink/black generation (total_ink_limit → -l, black_ink_limit → -L, black_generation → -k, k_locus → -K)
  • Shaper/data toggles (no_device_shaper → -ni, no_grid_position → -np, no_output_shaper → -no, no_embed_ti3 → -nc)
  • Input options (input_auto_scale_wp → -u, input_force_absolute → -ua, input_clip_above_wp → -uc), restrict_positive → -R, whitepoint_scale → -U
  • Threads (threads sets OMP_NUM_THREADS)
  • Extra args (extra_args) — for advanced flags not covered above; do not duplicate -c/-d here.

If an option is empty or false, it is omitted from the colprof command.

Troubleshooting

• colprof not found: install ArgyllCMS and ensure colprof is on PATH, or set [colprof].run = false to create TI3 only.
• CSV/TI2 length mismatch: ensure the CSV rows equal the number of TI2 patches; pairing is by index with no re-ordering.
• SAMPLE_LOC missing: if TI2 provides no SAMPLE_LOC and lacks layout headers, SAMPLE_LOC will not be written — this is expected.
• Spectral not detected: CSV must include 400–700 nm at 10 nm bands to be treated as spectral.
• ICC not created: ensure [colprof].run = true and output path is writable.
• Source ICC for gamut mapping: place it in src/input/ or provide an absolute path.