. 2024 Apr 30;13(9):1262. doi: 10.3390/plants13091262

Table 3.

Color indices related to narrowband reflectance indices.

Color Indices	Narrowband Reflectance Indices	Reference
GR	Normalized Difference Vegetation Index (NDVI)	[44,113]
GR	Narrowband spectral indices Simple Ratio Vegetation Index (SRVI) Simple Ration Red Edge (SRRE) Normalized Difference Red Edge (NDRE) Canopy Chlorophyll Content Index (CCCI)	[44]
$N G R D I$	Spectral indices (R₉₄₄ − R₇₅₈)/(R₉₄₄ + R₇₅₈), R₉₄₄/R₇₅₈	[52]
$N G R D I$	Narrowband spectral indices Simple Ratio Vegetation Index (SRVI) Simple Ration Red Edge (SRRE) Normalized Difference Red Edge (NDRE) Normalized Difference Vegetation Index (NDVI) Canopy Chlorophyll Content Index (CCCI)	[44]
ExG	Normalized Difference Vegetation Index (NDVI) Green Red Normalized Difference index (VARI) Simple ratio of NIR and Red (SR) Green Chlorophyll index (CI_green)	[131]
ExG	Spectral indices (R₉₄₄ − R₇₅₈)/(R₉₄₄ + R₇₅₈), R₉₄₄/R₇₅₈	[52]
VARI	Spectral indices (R₉₄₄ − R₇₅₈)/(R₉₄₄ + R₇₅₈), R₉₄₄/R₇₅₈	[52]
VARI	Narrowband spectral indices Simple Ratio Vegetation Index (SRVI) Simple Ration Red Edge (SRRE) Normalized Difference Red Edge (NDRE) Normalized Difference Vegetation Index (NDVI) Canopy Chlorophyll Content Index (CCCI)	[44]
VARIs	Normalized Difference Vegetation Index (NDVI) Green Red Normalized Difference index (VARI) Simple ratio of NIR and Red (SR) Green Chlorophyll index (CI_green)	[131]
NDBGRI	Narrowband spectral indices Simple Ratio Vegetation Index (SRVI) Simple Ration Red Edge (SRRE) Normalized Difference Red Edge (NDRE) Normalized Difference Vegetation Index (NDVI) Canopy Chlorophyll Content Index (CCCI)	[44]
GMR
NDI
SAVI_green
OSAVIgreen
EVI_green
EVI2_green
Hue (HSB)
DGCI (HSB)
RGRI	Spectral indices (R₉₄₄ − R₇₅₈)/(R₉₄₄ + R₇₅₈), R₉₄₄/R₇₅₈	[52]
GLI
VEG
CIVE
MGRVI

The determination coefficients (R²) for the regressions describing relation between color indices and narrowband reflectance indices are about 0.50 and more (mostly 0.70–0.96) excluding GMR. The last color index is weakly related to narrowband reflectance indices in some cases (e.g., R² could be 0.38 for GMR and SRRE [44]).