1. Overview

The lepton_cci module provides high-level command functions for configuring and controlling the Lepton thermal sensor via the CCI (Command and Control Interface). This module abstracts the low-level CCI protocol and provides convenient API functions.

1.1. Key Features

  • Temperature reading (FPA and AUX sensors)

  • AGC (Automatic Gain Control) management

  • Emissivity configuration for radiometric measurements

  • ROI (Region of Interest) configuration

  • Scene statistics and spotmeter control

  • TLinear resolution settings

  • Video source and format control

  • Flux linear parameters management

2. Supported Functions

2.1. Temperature Reading

  • Lepton_GetTemperature(): Read FPA and AUX temperatures

2.2. AGC Control

  • Lepton_EnableAGC(): Enable/disable AGC

    • When enabled: Provides 8-bit contrast-enhanced images

    • When disabled: Provides 14-bit raw radiometric data (with TLinear on radiometric sensors)

2.3. Radiometric Configuration (Lepton 3.5 only)

  • Lepton_SetEmissivity(): Configure material emissivity (0-100%)

  • Lepton_GetFluxLinearParameters() / Lepton_SetFluxLinearParameters(): Scene calibration

  • Lepton_GetTLinearResolution() / Lepton_SetTLinearResolution(): Temperature resolution mode

2.4. ROI Management

  • Spotmeter: Lepton_GetSpotmeterROI() / Lepton_SetSpotmeterROI()

  • Scene: Lepton_GetSceneROI() / Lepton_SetSceneROI()

  • AGC: Lepton_GetAGCROI() / Lepton_SetAGCROI()

  • Video Focus: Lepton_GetVideoFocusROI() / Lepton_SetVideoFocusROI()

2.5. Scene Data

  • Lepton_GetSpotmeter(): Read spotmeter statistics

  • Lepton_GetSceneStatistics(): Read scene min/max/avg

  • Lepton_GetUptime(): Sensor uptime in milliseconds

2.6. Video Control

  • Lepton_SetVideoFormat(): RAW14 or RGB888

  • Lepton_SetVideoSource(): Normal, ramp, or constant test patterns

  • Lepton_FreezeVideo(): Freeze/unfreeze output

  • Lepton_EnableTelemetry(): Enable/disable telemetry data

3. Implementation Details

This module wraps low-level CCI functions (see CCI Low-Level) with device state management:

  • Validates device initialization

  • Manages radiometric/non-radiometric modes

  • Synchronizes AGC and TLinear states

  • Provides error checking and logging

3.1. Example: AGC vs TLinear

// Non-radiometric sensors: AGC only
if (!device.Internal.isRadiometric) {
    Lepton_EnableAGC(&device, true, &status);  // Enable AGC
}

// Radiometric sensors: AGC or TLinear
if (device.Internal.isRadiometric) {
    Lepton_EnableAGC(&device, false, &status); // Disable AGC → enables TLinear
    // Now get 14-bit temperature data
}

4. Error Handling

All functions return Lepton_Error_t:

  • LEPTON_ERR_OK: Success

  • LEPTON_ERR_INVALID_ARG: Invalid parameters

  • LEPTON_ERR_NOT_INITIALIZED: Device not initialized

  • LEPTON_ERR_NOT_SUPPORTED: Feature not available (e.g., TLinear on Lepton 3.0)

5. Usage Example

Lepton_Result_t status;

// Read temperatures
uint16_t fpa, aux;
Lepton_GetTemperature(&device, &fpa, &aux, &status);
float fpa_celsius = Lepton_KelvinToCelsius(fpa);

// Configure for radiometric mode
Lepton_EnableAGC(&device, false, &status);        // Disable AGC
Lepton_SetEmissivity(&device, 98, &status);       // Human skin
Lepton_SetTLinearResolution(&device, TLINEAR_RES_0_1, &status);

// Set spotmeter ROI (center of image)
Lepton_ROI_t roi = {
    .Start = {.X = 70, .Y = 50},
    .End = {.X = 90, .Y = 70}
};
Lepton_SetSpotmeterROI(&device, &roi, &status);

// Read spotmeter
Lepton_Spotmeter_t spot;
Lepton_GetSpotmeter(&device, &spot, &status);
float temp = Lepton_KelvinToCelsius(spot.Value);

6. See Also

7. License

Copyright © Daniel Kampert, 2026 | GNU GPL v3.0

Website: https://www.kampis-elektroecke.de