Computational analysis of the photograph of the artwork A Minor - Research on Harmony - Variation 3 (AQC0711) [1] by Arnaud Quercy [2], according to IDS-CMP-2025 [3], on an image 1000 pixels on its longer side, on 2025-10-03. Each colour is located in the Munsell system and named according to the ISCC-NBS system (267 names, National Bureau of Standards, 1976). The image divides into 32 flat areas. The largest are very pale purple (18%), blackish purple (13%) and dark orange yellow (11%). Among the others, those that stand out most sharply from their surroundings are blackish blue on the left (0.8%), very light purple in the centre (0.4%) and pale purplish pink at the bottom (0.7%). By colour name family: red 23%, pink 18%, purple 14%, yellow 10%, orange yellow 10%, blue 6.9%, brown 6.3%, black 5.8% and orange 4.4%.
Context
Analysis performed according to IDS-CMP-2025 [3]: (a) colours named by Munsell and ISCC-NBS, areas and flat areas, (b) texture, (c) brightness and contrast, (d) spatial distribution. Source image: 3024x4032 pixels. Analysis date: 2025-10-03.
A) Color Analysis
Flat areas
Ranked by contrast with their surroundings (CIEDE2000). Strokes thinner than 10 pixels are excluded (2).
| Rank |
Colour |
ISCC-NBS name |
Munsell |
Area |
Contrast |
Position |
| 1 |
262937 |
blackish blue |
1.0PB 1.7/1.3 |
0.8% |
57.6 |
on the left |
| 2 |
E4C3E2 |
very light purple |
7.3P 8.2/5.3 |
0.4% |
40.6 |
in the centre |
| 3 |
E8C3C8 |
pale purplish pink |
7.1RP 8.2/4.1 |
0.7% |
40.4 |
at the bottom |
| 4 |
110D1A |
blackish purple |
2.1P 0.4/1.3 |
13% |
37.0 |
at the bottom |
| 5 |
DEC0DE |
very pale purple |
7.3P 8.1/4.1 |
18% |
34.7 |
at the top right |
| 6 |
EEC5D0 |
pale purplish pink |
3.5RP 8.3/4.5 |
0.3% |
34.3 |
in the centre |
| 7 |
A26F39 |
brownish orange |
6.2YR 5.0/6.5 |
3.8% |
31.9 |
at the bottom right |
| 8 |
C5343E |
strong red |
5.5R 4.4/12.9 |
4.6% |
29.8 |
in the centre |
| 9 |
A92848 |
strong red |
1.7R 3.9/11.6 |
9.4% |
29.3 |
at the bottom right |
| 10 |
D4B4A6 |
grayish yellowish pink |
3.0YR 7.5/2.9 |
1.9% |
28.7 |
at the bottom left |
| 11 |
DC993C |
moderate orange yellow |
9.0YR 6.8/9.4 |
1.5% |
28.0 |
on the right |
| 12 |
AB395A |
moderate purplish red |
9.6RP 4.2/10.6 |
0.7% |
27.7 |
at the bottom left |
| 13 |
D8422B |
vivid reddish orange |
8.2R 5.0/14.5 |
0.5% |
26.6 |
on the right |
| 14 |
DBB4B3 |
moderate pink |
2.5R 7.6/3.7 |
0.8% |
25.3 |
at the top |
| 15 |
554F2F |
moderate olive |
6.8Y 3.2/3.0 |
0.1% |
23.9 |
at the bottom right |
| 16 |
B7B6B7 |
light gray |
N 7.3/ |
0.3% |
21.5 |
at the top left |
| 17 |
B28043 |
dark orange yellow |
9.3YR 5.7/6.6 |
11% |
21.3 |
at the top |
| 18 |
C59642 |
dark orange yellow |
0.4Y 6.3/7.4 |
0.6% |
19.9 |
in the centre |
| 19 |
C9313D |
vivid red |
5.7R 4.6/13.6 |
8.2% |
18.2 |
at the bottom |
| 20 |
541D2C |
very dark red |
3.0R 1.9/5.8 |
0.1% |
17.7 |
at the bottom left |
| 21 |
A66239 |
brownish orange |
4.0YR 4.8/6.8 |
0.2% |
16.1 |
in the centre |
| 22 |
E9CACD |
light pink |
2.2R 8.4/3.1 |
0.4% |
15.4 |
in the centre |
| 23 |
D2A44E |
moderate orange yellow |
0.9Y 6.9/7.9 |
1.2% |
15.1 |
at the top |
| 24 |
D3657C |
deep pink |
9.6RP 5.6/10.6 |
2.0% |
14.1 |
in the centre |
| 25 |
D7C292 |
grayish yellow |
4.1Y 7.9/3.6 |
9.8% |
14.0 |
at the top left |
| 26 |
B67434 |
brownish orange |
6.7YR 5.3/7.8 |
0.9% |
12.5 |
in the centre |
| 27 |
8C4436 |
moderate reddish brown |
9.8R 3.7/6.7 |
0.8% |
12.1 |
at the bottom |
| 28 |
D5AA92 |
moderate yellowish pink |
4.1YR 7.2/3.8 |
7.1% |
8.6 |
on the left |
| 29 |
E7AE64 |
moderate orange yellow |
8.7YR 7.3/7.4 |
0.4% |
5.8 |
on the right |
| 30 |
CF8C8A |
dark pink |
3.3R 6.4/5.8 |
0.1% |
2.8 |
on the left |
| 31 |
2D344B |
grayish purplish blue |
6.1PB 2.2/3.4 |
0.4% |
1.8 |
at the bottom left |
| 32 |
0B090D |
black |
N 0.3/ |
0.1% |
1.7 |
at the bottom right |
Colour name families
| Family |
Area |
| red |
23% |
| pink |
18% |
| purple |
14% |
| yellow |
10% |
| orange yellow |
10% |
| blue |
6.9% |
| brown |
6.3% |
| black |
5.8% |
| orange |
4.4% |
B) Texture Analysis
| Metric |
Value |
| Global Roughness |
0.249 |
| Mean Local Roughness |
0.017 |
| Roughness Uniformity |
0.019 |
| Edge Density |
0.054 |
| Mean Gradient Magnitude |
0.134 |
| Gradient Variance |
0.046 |
| Gradient Smoothness |
0.0 |
| Directional Coherence |
0.011 |
| Pattern Complexity |
0.119 |
| Pattern Repetition |
1.0 |
| Detail Frequency Ratio |
0.623 |
| Spatial Variation |
0.198 |
| Texture Consistency |
0.594 |
C) Brightness & Contrast Analysis
| Metric |
Value |
| Mean Brightness |
0.516 |
| Brightness Variance |
0.249 |
| Brightness Uniformity |
0.517 |
| Brightness Skewness |
-0.401 |
| Brightness Entropy |
7.494 |
| Rms Contrast |
0.249 |
| Michelson Contrast |
1.0 |
| Weber Contrast |
0.87 |
| Mean Local Contrast |
0.018 |
| Contrast Uniformity |
0.0 |
| Dynamic Range |
1.0 |
| Effective Dynamic Range |
0.788 |
| Shadow Percentage |
22.525 |
| Midtone Percentage |
38.486 |
| Highlight Percentage |
38.989 |
| Shadow Clipping |
0.007 |
| Highlight Clipping |
0.0 |
| Tonal Balance |
0.177 |
| Fine Contrast |
0.009 |
| Medium Contrast |
0.023 |
| Coarse Contrast |
0.033 |
| Multiscale Contrast Ratio |
0.282 |
| Edge Contrast |
0.134 |
| Contrast Clustering |
0.406 |
D) Spatial Distribution Analysis
| Metric |
Value |
| Spatial Coherence |
0.764 |
| Color Clustering |
0.698 |
| Color Transition Smoothness |
0.662 |
| Transition Uniformity |
0.681 |
| Sharp Transition Ratio |
0.1 |
| Transition Directionality |
0.02 |
| Mean Saturation |
0.479 |
| Saturation Variance |
0.056 |
| Low Saturation Ratio |
0.299 |
| Medium Saturation Ratio |
0.462 |
| High Saturation Ratio |
0.239 |
| Saturation Clustering |
0.998 |
| Hue Concentration |
0.671 |
| Complementary Balance |
0.037 |
| Analogous Dominance |
0.809 |
| Temperature Bias |
0.766 |
Methodology
Computational analysis of a photograph of the artwork, reduced to 1,000 pixels on its longer side and filtered by a 3×3 median to remove grain. Colours: each pixel (sRGB rounded to 5 bits per channel) receives its Munsell notation and ISCC-NBS name from a table computed once from published data (Munsell renotation; ISCC-NBS blocks, NBS Special Publication 440, 1976), never from the artworks. Flat areas: connected regions of one name, merged with their neighbours while the CIEDE2000 difference between their mean colours stays below 10; an area is kept from 0.05% of the image; contrast with the surroundings measured 4 to 12 pixels from the edge. Texture: intensity standard deviation, local standard deviation, edge density (Canny), local binary patterns. Brightness: mean, variance, RMS, Michelson and local contrast, shadow / midtone / highlight distribution. Distribution: spatial coherence, transitions, saturation. Methods are deterministic and reproducible. Limits: the measurement concerns the photograph, including its lighting and white balance; two neighbouring areas less than 10 apart are merged.
