Create a Film Density plugin in Resolve for free — use this awesome DCTL code for Resolve 17 and above.
What is DCTL?
DCTL is a coding language for Davinci Resolve, which means that plugins can be easily installed and modified by users themselves.
How to use DCTLs
Save the code below as a .dctl text file from any text editor and place it in your Resolve LUT folder. Then add the DCTL OFX plugin to any node in your node tree to load the DCTL file (after restarting Resolve first).
Film Density DCTL Code
DEFINE_UI_PARAMS(p_Den, Film Density, DCTLUI_SLIDER_FLOAT, 0, 0, 2, 0.001)
DEFINE_UI_PARAMS(p_WR, Red Weight, DCTLUI_SLIDER_FLOAT, 1, 0, 2, 0.001)
DEFINE_UI_PARAMS(p_WG, Green Weight, DCTLUI_SLIDER_FLOAT, 1, 0, 2, 0.001)
DEFINE_UI_PARAMS(p_WB, Blue Weight, DCTLUI_SLIDER_FLOAT, 1, 0, 2, 0.001)
DEFINE_UI_PARAMS(p_LimitS, Low Saturation Limiter, DCTLUI_SLIDER_FLOAT, 0, 0, 1, 0.001)
DEFINE_UI_PARAMS(p_LimitL, Low Luma Limiter, DCTLUI_SLIDER_FLOAT, 0, 0, 1, 0.001)
DEFINE_UI_PARAMS(p_Display, Display Alpha, DCTLUI_CHECK_BOX, 0)
#if (__RESOLVE_VER_MAJOR__ < 17)
__DEVICE__ float _floorf( float A) {
return (float)_floor(A);
}
#endif
__DEVICE__ float3 RGB_to_HSV( float3 RGB ) {
float3 HSV;
float min = _fminf(_fminf(RGB.x, RGB.y), RGB.z);
float max = _fmaxf(_fmaxf(RGB.x, RGB.y), RGB.z);
HSV.z = max;
float delta = max - min;
if (max != 0.0f) {
HSV.y = delta / max;
} else {
HSV.y = 0.0f;
HSV.x = 0.0f;
return HSV;
}
if (delta == 0.0f) {
HSV.x = 0.0f;
} else if (RGB.x == max) {
HSV.x = (RGB.y - RGB.z) / delta;
} else if (RGB.y == max) {
HSV.x = 2.0f + (RGB.z - RGB.x) / delta;
} else {
HSV.x = 4.0f + (RGB.x - RGB.y) / delta;
}
HSV.x *= 1.0f / 6.0f;
if (HSV.x < 0.0f)
HSV.x += 1.0f;
return HSV;
}
__DEVICE__ float3 HSV_to_RGB(float3 HSV) {
float3 RGB;
if (HSV.y == 0.0f) {
RGB.x = RGB.y = RGB.z = HSV.z;
} else {
HSV.x *= 6.0f;
float i = _floorf(HSV.x);
float f = HSV.x - i;
i = i >= 0.0f ? _fmod(i, 6.0f) : _fmod(i, 6.0f) + 6.0f;
float p = HSV.z * (1.0f - HSV.y);
float q = HSV.z * (1.0f - HSV.y * f);
float t = HSV.z * (1.0f - HSV.y * (1.0f - f));
RGB.x = i == 0.0f ? HSV.z : i == 1.0f ? q : i == 2.0f ? p : i == 3.0f ? p : i == 4.0f ? t : HSV.z;
RGB.y = i == 0.0f ? t : i == 1 ? HSV.z : i == 2.0f ? HSV.z : i == 3.0f ? q : i == 4.0f ? p : p;
RGB.z = i == 0.0f ? p : i == 1 ? p : i == 2.0f ? t : i == 3.0f ? HSV.z : i == 4.0f ? HSV.z : q;
}
return RGB;
}
__DEVICE__ float RGB_to_Sat( float3 RGB) {
float min = _fminf(_fminf(RGB.x, RGB.y), RGB.z);
float max = _fmaxf(_fmaxf(RGB.x, RGB.y), RGB.z);
float delta = max - min;
float Sat = max != 0.0f ? delta / max : 0.0f;
return Sat;
}
__DEVICE__ float3 Saturation(float3 RGB, float luma, float Sat) {
RGB.x = (1.0f - Sat) * luma + RGB.x * Sat;
RGB.y = (1.0f - Sat) * luma + RGB.y * Sat;
RGB.z = (1.0f - Sat) * luma + RGB.z * Sat;
return RGB;
}
__DEVICE__ float get_luma(float3 RGB, float Rw, float Gw, float Bw) {
float R, G, B;
R = Rw + 1.0f - (Gw / 2.0f) - (Bw / 2.0f);
G = Gw + 1.0f - (Rw / 2.0f) - (Bw / 2.0f);
B = Bw + 1.0f - (Rw / 2.0f) - (Gw / 2.0f);
float luma = (RGB.x * R + RGB.y * G + RGB.z * B) / 3.0f;
return luma;
}
__DEVICE__ float Limiter(float val, float limiter) {
float alpha = limiter > 1.0f ? val + (1.0f - limiter) * (1.0f - val) : limiter >= 0.0f ? (val >= limiter ? 1.0f :
val / limiter) : limiter < -1.0f ? (1.0f - val) + (limiter + 1.0f) * val : val <= (1.0f + limiter) ? 1.0f :
(1.0 - val) / (1.0f - (limiter + 1.0f));
alpha = _saturatef(alpha);
return alpha;
}
__DEVICE__ float3 transform(int p_Width, int p_Height, int p_X, int p_Y, float p_R, float p_G, float p_B)
{
float3 rgbIn = make_float3(p_R, p_G, p_B);
if (p_Den == 0.0f && p_Display == 0)
return rgbIn;
float WR = 2.0f - p_WR;
float WG = 2.0f - p_WG;
float WB = 2.0f - p_WB;
float luma = get_luma(rgbIn, WR, WG, WB);
float SatA = 1.0f / (p_Den + 1.0f);
float3 rgbOut = Saturation(rgbIn, luma, SatA);
float alphaS, alphaL, alpha;
alphaS = alphaL = alpha = 1.0f;
if (p_LimitS > 0.0f) {
float sat = RGB_to_Sat(rgbIn);
alphaS = Limiter(sat, p_LimitS);
alpha = alphaS;
}
if (p_LimitL > 0.0f) {
alphaL = (rgbIn.x + rgbIn.y + rgbIn.z) / 3.0f;
alphaL = Limiter(alphaL, p_LimitL);
alpha *= alphaL;
}
rgbOut = RGB_to_HSV(rgbOut);
rgbOut.y *= 1.0f / SatA ;
rgbOut = HSV_to_RGB(rgbOut);
if (alpha < 1.0f)
rgbOut = rgbOut * alpha + (1.0f - alpha) * rgbIn;
if (p_Display)
return make_float3(alpha, alpha, alpha);
return rgbOut;
}Original Code
This is just a mirror to make sure this DCTL for Film Density does not go offline or gets deleted. The original DCTL can be found github.com.