From 84118f368a121f19946f32ee8bf822628a7d3e27 Mon Sep 17 00:00:00 2001 From: Tyler Erickson Date: Mon, 29 Apr 2024 20:24:02 +0000 Subject: [PATCH 1/2] Changed math images to MathJax --- README.md | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/README.md b/README.md index 43746ca..6c10a2f 100644 --- a/README.md +++ b/README.md @@ -101,14 +101,12 @@ Hereafter, some examples of the usage of the `values` dictionary to perform radi -A conventional way of deriving Top Of Atmosphere (TOA) Radiance -in ![formula](https://render.githubusercontent.com/render/math?math=W.sr^{-1}.m^{-3}) -from DN values using `scale` and `offset` in the following formula: +A conventional way of deriving Top Of Atmosphere (TOA) Radiance from $\mathrm{DN}$ values using `scale` and `offset` in the following formula: -![formula](https://render.githubusercontent.com/render/math?math=\color{gray}L_\lambda%20=%20scale%20\times%20DN%20%2B%20offset) +$$L_\lambda=\mathrm{scale}\times\mathrm{DN}+\mathrm{offset}$$ -where ![formula](https://render.githubusercontent.com/render/math?math=\color{gray}L_\lambda) is TOA Radiance -in ![formula](https://render.githubusercontent.com/render/math?math=\color{gray}W.sr^{-1}.m^{-3}). +where $L_\lambda$ is TOA Radiance +in $\mathrm{W}\!\cdot\!sr^{-1}\!\cdot\!m^{-3}$. For example, the above value conversion is described in the values dictionary as @@ -130,14 +128,14 @@ For example, the above value conversion is described in the values dictionary as In order to convert the above TOA radiance to TOA reflectance, the following formula can be used: -![formula](https://render.githubusercontent.com/render/math?math=\color{gray}R=(pi*L*d*d)/(ESUN*cos(s))) +$$R=\frac{pi \times L \times d \times d}{ESUN(b) \times cos(s)}$$ where: -- L is the spectral radiance for the band (see previous section) -- d is the earth-sun distance (in astronomical units) and depends on the acquisition’s day and month ([Core STAC specification](https://github.com/radiantearth/stac-spec/blob/master/item-spec/item-spec.md#properties-object)) -- ESUN(b) is the mean TOA solar irradiance (or [solar illumination](https://github.com/stac-extensions/eo#solar_illumination)) in W/m2/micrometers -- s is the [solar zenith angle](https://github.com/stac-extensions/view#item-properties) in degrees. +- $L$ is the spectral radiance for the band (see previous section) +- $d$ is the earth-sun distance (in astronomical units) and depends on the acquisition’s day and month ([Core STAC specification](https://github.com/radiantearth/stac-spec/blob/master/item-spec/item-spec.md#properties-object)) +- $ESUN(b)$ is the mean TOA solar irradiance (or [solar illumination](https://github.com/stac-extensions/eo#solar_illumination)) in $W/m^2/micrometers$ +- $s$ is the [solar zenith angle](https://github.com/stac-extensions/view#item-properties) in degrees. source: From 3379181dd6f08c9534210f619096e2d1afc2ed32 Mon Sep 17 00:00:00 2001 From: Emmanuel Mathot Date: Tue, 30 Apr 2024 09:47:29 +0200 Subject: [PATCH 2/2] Fix formatting in README.md --- README.md | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/README.md b/README.md index 6c10a2f..7b157ff 100644 --- a/README.md +++ b/README.md @@ -134,7 +134,8 @@ where: - $L$ is the spectral radiance for the band (see previous section) - $d$ is the earth-sun distance (in astronomical units) and depends on the acquisition’s day and month ([Core STAC specification](https://github.com/radiantearth/stac-spec/blob/master/item-spec/item-spec.md#properties-object)) -- $ESUN(b)$ is the mean TOA solar irradiance (or [solar illumination](https://github.com/stac-extensions/eo#solar_illumination)) in $W/m^2/micrometers$ +- $ESUN(b)$ is the mean TOA solar irradiance (or [solar illumination](https://github.com/stac-extensions/eo#solar_illumination)) + in $W/m^2/micrometers$ - $s$ is the [solar zenith angle](https://github.com/stac-extensions/view#item-properties) in degrees. source: