SPRAD86 March   2023 AM62A3 , AM62A3-Q1 , AM62A7 , AM62A7-Q1 , AM68A , AM69A

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Tuning Overview
  5. 3Hardware Requirement
  6. 4Software Requirement
    1. 4.1 Processor SDK Linux
    2. 4.2 TI's Reference Imaging Software
    3. 4.3 ISP Tuning Tool
  7. 5Sensor Software Development and Integration
    1. 5.1 Adding Sensor Driver to SDK
    2. 5.2 Updating GStreamer Plugins to Support the Sensor
      1. 5.2.1 Update TIOVX Modules
        1. 5.2.1.1 Source Code Change
        2. 5.2.1.2 Rebuild Modules
      2. 5.2.2 Update GStreamer Plugins
        1. 5.2.2.1 Source Code Change
        2. 5.2.2.2 Rebuild Plugins
        3. 5.2.2.3 Verify New Sensor in GStreamer Plugin
  8. 6Tuning Procedure
    1. 6.1 Verify Functional Operation of Camera Capturing
    2. 6.2 Enable Camera Streaming with Initial VPAC Configuration
      1. 6.2.1 Generate Configuration Files
      2. 6.2.2 Generate DCC Binary Files
      3. 6.2.3 Stream Video with the Initial Configuration
    3. 6.3 Adjust Camera Mounting
    4. 6.4 Capture Raw Images and Perform Basic Tuning
      1. 6.4.1 Launch the Tuning Tool and Create a Project
      2. 6.4.2 Tuning Order
      3. 6.4.3 Black Level Subtraction
      4. 6.4.4 Hardware 3A (H3A)
      5. 6.4.5 Auto White Balance (AWB)
        1. 6.4.5.1 Capture Raw Images for Different Lighting Conditions
        2. 6.4.5.2 Tuning AWB
      6. 6.4.6 Color Correction
    5. 6.5 Perform Fine Tuning
  9. 7Summary

6.4.2 Tuning Order

The AM6xA ISP (VPAC) consists of multiple functional blocks. Raw images are processed by these blocks one after another. The tuning tool allows to tune the ISP blocks in independent groups, with each group containing one or more ISP blocks. The tuning groups are referred as plugins, as shown in the tuning tool menu "Plug-ins":

GUID-20230224-SS0I-LFQN-JTPS-G2VCQ75SMPTX-low.png Figure 6-3 Plugins of DCC Tuning Tool
Note: Each plug-in has its own tuning guide which is available from Help -> Documentation drop down menu. These guides should be referenced during the tuning.

In general, these plugins should be tuned in the same order of ISP blocks when processing the raw image. Below is a recommended tuning order:

  1. Black Level Subtraction: Data pedestal (sensor black level) is typically specified by the sensor driver and can be calculated here for verification.
  2. H3A: Hardware 3A (Auto exposure, Auto focus, Auto white balance) statistics
  3. PCID: Pattern Conversion and IR Demosaicing (only for RGB+IR sensors)
  4. AWB: Auto White Balance
  5. Color Correction
  6. EE: Edge Enhancement
  7. Noise Filter 4
  8. Mesh LDC: Lens Distortion Correction
  9. CFAI + WDR: Color Filter Array Interpolation + Wide Dynamic Range
  10. LSC: Lens Shading Correction

After tuning each plug-in, a new set of XML files for VPAC configuration will be generated. These new XML files can replace those generated from the initial configuration to gradually improve image quality for live streaming.

In this application note, the IMX219 sensor in 1080p mode is used as an example for illustrating the tuning and calibration of black level, AWB, and color correction with the TDA4/AM6xA DCC tuning tool from TI. More details about tuning are available in the plug-in guides from the Help menu of the tuning tool. Other versions of ISP tuning tool from TI 3rd parties follow roughly the same procedure.