tcs34725: Remove IR compensation and improve illuminance and color temperature handling in extreme conditions (#7492)

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@RubenKelevra 2024-10-01 00:03:42 +02:00 committed by GitHub
parent 01e03b76a7
commit c1a28ba5e2
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@ -73,20 +73,21 @@ float TCS34725Component::get_setup_priority() const { return setup_priority::DAT
* @return Color temperature in degrees Kelvin
*/
void TCS34725Component::calculate_temperature_and_lux_(uint16_t r, uint16_t g, uint16_t b, uint16_t c) {
float r2, g2, b2; /* RGB values minus IR component */
float sat; /* Digital saturation level */
float ir; /* Inferred IR content */
float sat; /* Digital saturation level */
this->illuminance_ = 0; // Assign 0 value before calculation
this->color_temperature_ = 0;
this->illuminance_ = NAN;
this->color_temperature_ = NAN;
const float ga = this->glass_attenuation_; // Glass Attenuation Factor
static const float DF = 310.f; // Device Factor
static const float R_COEF = 0.136f; //
static const float G_COEF = 1.f; // used in lux computation
static const float B_COEF = -0.444f; //
static const float CT_COEF = 3810.f; // Color Temperature Coefficient
static const float CT_OFFSET = 1391.f; // Color Temperatuer Offset
const float ga = this->glass_attenuation_; // Glass Attenuation Factor
static const float DF = 310.f; // Device Factor
static const float R_COEF = 0.136f; //
static const float G_COEF = 1.f; // used in lux computation
static const float B_COEF = -0.444f; //
static const float CT_COEF = 3810.f; // Color Temperature Coefficient
static const float CT_OFFSET = 1391.f; // Color Temperatuer Offset
static const float MAX_ILLUMINANCE = 100000.0f; // Cap illuminance at 100,000 lux
static const float MAX_COLOR_TEMPERATURE = 15000.0f; // Maximum expected color temperature in Kelvin
static const float MIN_COLOR_TEMPERATURE = 1000.0f; // Maximum reasonable color temperature in Kelvin
if (c == 0) {
return;
@ -137,45 +138,48 @@ void TCS34725Component::calculate_temperature_and_lux_(uint16_t r, uint16_t g, u
if (c >= sat) {
if (this->integration_time_auto_) {
ESP_LOGI(TAG, "Saturation too high, sample discarded, autogain ongoing");
return;
} else {
ESP_LOGW(
TAG,
"Saturation too high, sample with saturation %.1f and clear %d treat values carefully or use grey filter",
sat, c);
}
}
/* AMS RGB sensors have no IR channel, so the IR content must be */
/* calculated indirectly. */
ir = ((r + g + b) > c) ? (r + g + b - c) / 2 : 0;
/* Remove the IR component from the raw RGB values */
r2 = r - ir;
g2 = g - ir;
b2 = b - ir;
// discarding super low values? not recemmonded, and avoided by using auto gain.
if (r2 == 0) {
// legacy code
if (!this->integration_time_auto_) {
ESP_LOGW(TAG,
"No light detected on red channel, switch to auto gain or adjust timing, values will be unreliable");
"Saturation too high, sample with saturation %.1f and clear %d lux/color temperature cannot reliably "
"calculated, reduce integration/gain or use a grey filter.",
sat, c);
return;
}
}
// Lux Calculation (DN40 3.2)
float g1 = R_COEF * r2 + G_COEF * g2 + B_COEF * b2;
float g1 = R_COEF * (float) r + G_COEF * (float) g + B_COEF * (float) b;
float cpl = (this->integration_time_ * this->gain_) / (ga * DF);
this->illuminance_ = g1 / cpl;
this->illuminance_ = std::max(g1 / cpl, 0.0f);
if (this->illuminance_ > MAX_ILLUMINANCE) {
ESP_LOGW(TAG, "Calculated illuminance greater than limit (%f), setting to NAN", this->illuminance_);
this->illuminance_ = NAN;
return;
}
if (r == 0) {
ESP_LOGW(TAG, "Red channel is zero, cannot compute color temperature");
return;
}
// Color Temperature Calculation (DN40)
/* A simple method of measuring color temp is to use the ratio of blue */
/* to red light, taking IR cancellation into account. */
this->color_temperature_ = (CT_COEF * b2) / /** Color temp coefficient. */
r2 +
CT_OFFSET; /** Color temp offset. */
/* to red light. */
this->color_temperature_ = (CT_COEF * (float) b) / (float) r + CT_OFFSET;
// Ensure the color temperature stays within reasonable bounds
if (this->color_temperature_ < MIN_COLOR_TEMPERATURE) {
ESP_LOGW(TAG, "Calculated color temperature value too low (%f), setting to NAN", this->color_temperature_);
this->color_temperature_ = NAN;
} else if (this->color_temperature_ > MAX_COLOR_TEMPERATURE) {
ESP_LOGW(TAG, "Calculated color temperature value too high (%f), setting to NAN", this->color_temperature_);
this->color_temperature_ = NAN;
}
}
void TCS34725Component::update() {