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

Tuning AWB

After raw images are captured, start the AWB tuning from the "Plug-ins" drop down menu. Import the raw images one by one in the “Reference files” tab (see the AWB plugin guide for details) and enter the parameter values for each image:

  • Color Temperature: this must be what is used when capturing the raw image. For example, the value should be 6500 for D65 lighting condition.
  • Exposure, Gain, and Aperture: these values are not really used for AWB and therefore can be ignored.
  • Black Level: this must be the pedestal value that was measured in the Black Level Subtraction plugin. In this example, IMX219 has a measured black level of 63 in 10-bit mode.

Please pay special attention when selecting the corners of the color checker chart:

  • Starting with the upper left corner, click on the four corners of the color checker chart in clock-wise order.
  • After the four corners are selected, the tool automatically identifies the 24 patches and display the selection of each patch as shown below.

#GUID-EE3717A6-649F-4999-84B2-213465839603 through #FIG_HFZ_DVC_RWB show an example of importing one raw image for AWB tuning.

GUID-20230224-SS0I-N0SN-QJKS-G2QX5SSHRQSQ-low.png Figure 6-12 Auto White Balance Tuning
GUID-20230224-SS0I-M48L-CRSP-N6TCL8C3CTCW-low.png Figure 6-13 Choosing Corners of Color Checker Chart

After importing all raw images, follow the AWB plugin guide to do the tuning. If tuning is successful, reference Cb-Cr plot scheme will be displayed. Below is the result plot using the raw images shown above.

GUID-20230224-SS0I-5VMK-XH4Z-R0QDTZSWPV1W-low.png Figure 6-14 Auto White Balance Tuning Results

After tuning is done, generate new output XML files and new binary files as done in tuning Black Level Subtraction. Then use the newly generated DCC binary files to stream and capture. #FIG_GVT_KVC_RWB and #FIG_RZ4_PVC_RWB show images captured before AWB tuning and after AWB tuning (all gray patches appear neutral in the image after AWB tuning).

GUID-20230224-SS0I-V56W-HKV5-RNHWBPQBKZHB-low.jpgFigure 6-15 Image Before Auto White Balance Tuning
GUID-20230224-SS0I-RZ3J-7LBK-W0BNX03H9SSD-low.jpgFigure 6-16 Image After Auto White Balance Tuning