Source: https://guthlabs.ai/docs/instruments/gamut-coverage-color-space-notes-panel/implementation/

instrument implementation / implementation-contract

# Gamut Coverage / Color Space Notes Panel implementation

A source-bound implementation contract for Gamut Coverage / Color Space Notes Panel; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t7-059

**Effect**: Computation or source lookup only

## Input and validation requirements

The boundary and undefined-selection cases require explicit validation, and the worked area calculation exposes a likely implementation hazard: inconsistent triangle-area arithmetic or chromaticity-coordinate tables can materially change reported coverage. The branch vector also shows that the correct area from the stated sRGB and Adobe RGB coordinates is 0.11205 and 0.15115, so any other values indicate a lookup or formula defect.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "color_spaces": [
      "Adobe RGB (1998)",
      "sRGB"
    ],
    "reference_color_space": "sRGB",
    "metric": "CIE 1931 xy primary-triangle area ratio"
  },
  "expected_outputs": {
    "Adobe_RGB_1998_triangle_area_xy2": 0.15115,
    "sRGB_triangle_area_xy2": 0.11205,
    "Adobe_RGB_1998_relative_to_sRGB_percent": 134.8951
  },
  "reference_data": {
    "Adobe_RGB_1998_primaries_xy": {
      "red": [
        0.64,
        0.33
      ],
      "green": [
        0.21,
        0.71
      ],
      "blue": [
        0.15,
        0.06
      ]
    },
    "Adobe_RGB_1998_source_convention": "Adobe RGB (1998) published color-space specification, widely tabulated standard value",
    "sRGB_primaries_xy": {
      "red": [
        0.64,
        0.33
      ],
      "green": [
        0.3,
        0.6
      ],
      "blue": [
        0.15,
        0.06
      ]
    },
    "sRGB_source_convention": "IEC 61966-2-1:1999 / ITU-R BT.709, widely tabulated standard value"
  },
  "working": "For Adobe RGB, A = 0.5 × |(0.64×0.71 + 0.21×0.06 + 0.15×0.33) − (0.33×0.21 + 0.71×0.15 + 0.06×0.64)| = 0.5 × |(0.4544 + 0.0126 + 0.0495) − (0.0693 + 0.1065 + 0.0384)| = 0.5 × |0.5165 − 0.2142| = 0.15115. For sRGB, A = 0.5 × |(0.64×0.60 + 0.30×0.06 + 0.15×0.33) − (0.33×0.30 + 0.60×0.15 + 0.06×0.64)| = 0.5 × |(0.384 + 0.018 + 0.0495) − (0.099 + 0.09 + 0.0384)| = 0.5 × |0.4515 − 0.2274| = 0.11205. Relative percentage = (0.15115 ÷ 0.11205) × 100 = 134.8951%."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/gamut-coverage-color-space-notes-panel/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/gamut-coverage-color-space-notes-panel/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/gamut-coverage-color-space-notes-panel/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche7/tranche7-results.json`