Assistance with Enabling/Disabling Image Overlay via GPIO in ACAP Application

[ThijsFuncke630]

Hello,

We are developing an ACAP application and want to toggle an image overlay on and off using a GPIO input. The GPIO functionality is working fine, but I am unable to find any relevant information in the ACAP documentation regarding how to enable or disable the image overlay.

Any help would be greatly appreciated.

Thank you,
Thijs Funcke

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[vivekatoffice]

Hi @ThijsFuncke630 ,
You can use the VAPIX APIs: Overlay API for this inside the ACAP. This example will be helpful to you: vapix.

Dynamic_Overlay_API_VAPIX.mp4

Or

Control the overlays directly using axoverlay and subscribe_to_event. AXIS Metadata Monitor can be used to get the ONVIF namespace "tns1" for interested GPIO or Axis I/Os.

I/O port management: The I/O port management API makes it possible to retrieve information about the ports and apply product dependent configurations.

[ThijsFuncke630]

Hello @vivekatoffice,

Thank you for the quick reply!

This is exactly what we need.
However, we want to use this within an ACAP application written in C. Do you have any examples or guidelines on how we can implement this in a C environment with ACAP?

Any help or examples would be greatly appreciated.

Best regards,
Thijs Funcke.

[vivekatoffice]

HI @ThijsFuncke630 ,

Try following this example: object-detection-yolov5

My idea is that this example is using Bounding Box API for drawing. What is it that you are trying to display? Cairo is a 2D graphics library with support for multiple output devices. Currently supported output targets include the X Window System via both Xlib and XCB, Quartz, Win32, image buffers, PostScript, PDF, and SVG file output.

You can explore this repository also from Cacsjep but written in Go language.
goxis_examples

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I hope the above information helps with your use case! But I still believe vapix example will be the easiest to implement yourself. 😉

[ThijsFuncke630]

Thanks again for this example,

We are working on a solution where a user has a switch connected to a GPIO pin. When the switch is activated, the system will perform the following actions:

Privacy Mode Activation: An image overlay will be displayed over the camera feed, clearly indicating that Privacy Mode is enabled. The overlay will feature a message that reads "Privacy Mode Enabled", along with a logo.

LED Indicator: An LED connected to another GPIO pin will light up, providing some feedback that Privacy Mode has been activated.

[vivekatoffice]

Feel free to re-open it OR share the solution/alternative/comment if already resolved👁️‍🗨️