[libcamera-devel] [RFC 4/4] apps: cam: Add option to set stream orientation

[Umang Jain]

Hi Jacopo,

Thank you for the patch.

On 6/20/23 7:59 PM, Jacopo Mondi via libcamera-devel wrote:
> Add a '--orientation|-o' option to the cam test application to set
> an orientation to the image stream.
>
> Supported values are the ones obtained by applying flips to the camera
> sensor:
> - rot180: Rotate 180 degrees
> - flip: vertical flip
> - mirror: horizontal flip

 From an application PoV, it should be able to set every possible 
rotation defined in enum Orientation, I think.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi at ideasonboard.com>
> ---
>   src/apps/cam/camera_session.cpp | 17 +++++++++++++++++
>   src/apps/cam/main.cpp           |  5 +++++
>   src/apps/cam/main.h             |  1 +
>   3 files changed, 23 insertions(+)
>
> diff --git a/src/apps/cam/camera_session.cpp b/src/apps/cam/camera_session.cpp
> index 8fcec6304d66..2d6a1440cde2 100644
> --- a/src/apps/cam/camera_session.cpp
> +++ b/src/apps/cam/camera_session.cpp
> @@ -65,6 +65,23 @@ CameraSession::CameraSession(CameraManager *cm,
>   		return;
>   	}
>
> +	if (options_.isSet(OptOrientation)) {
> +		std::string orient = options_[OptOrientation].toString();
> +		if (orient == "rot180") {
> +			config->orientation =
> +				libcamera::CameraConfiguration::rotate180;
> +		} else if (orient == "mirror") {
> +			config->orientation =
> +				libcamera::CameraConfiguration::flipRotate0;
> +		} else if (orient == "flip") {
> +			config->orientation =
> +				libcamera::CameraConfiguration::flipRotate180;
> +		} else {
> +			std::cerr << "Invalid orientation " << orient << std::endl;
> +			return;

If we want to restrict the orientation not supported by libcamera, we 
should restrict them at libcamera level itself.

Restricting them at application level doesn't make sense to me.
> +		}
> +	}
> +
>   	/* Apply configuration if explicitly requested. */
>   	if (StreamKeyValueParser::updateConfiguration(config.get(),
>   						      options_[OptStream])) {
> diff --git a/src/apps/cam/main.cpp b/src/apps/cam/main.cpp
> index 5d8a57bc14e5..8698d5eedcf8 100644
> --- a/src/apps/cam/main.cpp
> +++ b/src/apps/cam/main.cpp
> @@ -133,6 +133,11 @@ int CamApp::parseOptions(int argc, char *argv[])
>   			 "Capture until interrupted by user or until <count> frames captured",
>   			 "capture", ArgumentOptional, "count", false,
>   			 OptCamera);
> +
> +	parser.addOption(OptOrientation, OptionString,
> +			 "The camera stream image orientation (rot180, mirror, flip)",
> +			 "orientation", ArgumentRequired, "orientation", false,
> +			 OptCamera);
>   #ifdef HAVE_KMS
>   	parser.addOption(OptDisplay, OptionString,
>   			 "Display viewfinder through DRM/KMS on specified connector",
> diff --git a/src/apps/cam/main.h b/src/apps/cam/main.h
> index 526aecece3f3..4aa959b32e13 100644
> --- a/src/apps/cam/main.h
> +++ b/src/apps/cam/main.h
> @@ -17,6 +17,7 @@ enum {
>   	OptList = 'l',
>   	OptListProperties = 'p',
>   	OptMonitor = 'm',
> +	OptOrientation = 'o',
>   	OptSDL = 'S',
>   	OptStream = 's',
>   	OptListControls = 256,
> --
> 2.40.1
>