rpicam_still: Add RGB/BGR 48bpp support

[naushir]

Add support for 48-bpp RGB/BGR formats that can be generated by the PiSP. rpicam-still can select this with the "--encoding rgb48" command line option.

[naushir]

Cannot really merge this until we have RGB161616 support in libcamera.

[schoolpost]

Cannot really merge this until we have RGB161616 support in libcamera.

coming soon?

[naushir]

We will try to get it in our next release. It all depends on how and when we can start the driver upstreaming process. You are welcome to try the change out, but note that you will need the latest kernel and build/install libcamera from https://github.com/raspberrypi/libcamera/tree/next.

[schoolpost]

We will try to get it in our next release. It all depends on how and when we can start the driver upstreaming process. You are welcome to try the change out, but note that you will need the latest kernel and build/install libcamera from https://github.com/raspberrypi/libcamera/tree/next.

Is this format only supported in the Still stream? or also video?

Does not work in my testing when used like this:

Mode selection for 2028:1520:12:U(24)
    SRGGB10_CSI2P,1332x990/120.048 - Score: 3456.22
    SRGGB12_CSI2P,2028x1080/50.0275 - Score: 1083.84
    SRGGB12_CSI2P,2028x1520/40.0096 - Score: 0
    SRGGB12_CSI2P,4056x3040/10 - Score: 28887
[0:00:51.513902245] [1405]  WARN V4L2 v4l2_pixelformat.cpp:346 Unsupported V4L2 pixel format <INVALID>
[0:00:51.513919760] [1405]  WARN Formats formats.cpp:997 Unsupported pixel format 0x00000000
[0:00:51.513916383] [1405] ERROR RPI pisp.cpp:228 Pixel format <INVALID> unsupported
[0:00:51.513935865] [1405] FATAL default pisp.cpp:229 assertion "0" failed in toPiSPImageFormat()
Backtrace:
/usr/local/lib/aarch64-linux-gnu/libcamera.so.0.1(+0x104e34) [0x7ffef1fc4e34]
/usr/local/lib/aarch64-linux-gnu/libcamera.so.0.1(_ZNK9libcamera14PiSPCameraData16platformValidateEPNS_3RPi22RPiCameraConfigurationE+0x3fc) [0x7ffef1fc8040]
/usr/local/lib/aarch64-linux-gnu/libcamera.so.0.1(_ZN9libcamera3RPi22RPiCameraConfiguration8validateEv+0x358) [0x7ffef1fb0098]
/usr/local/lib/aarch64-linux-gnu/rpicam_app.so.1.4.1(_ZN9RPiCamApp12setupCaptureEv+0x24) [0x7ffef2268434]
/usr/local/lib/aarch64-linux-gnu/rpicam_app.so.1.4.1(_ZN9RPiCamApp14ConfigureVideoEjh+0x354) [0x7ffef226d6f4]
cinepi-raw(+0x25fa8) [0x5555c2b65fa8]
/lib/aarch64-linux-gnu/libc.so.6(+0x27780) [0x7ffef18c7780]
/lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0x98) [0x7ffef18c7858]
cinepi-raw(+0x27ab0) [0x5555c2b67ab0]
Aborted

Hardcoded the format in the configureVideo Method:

void RPiCamApp::ConfigureVideo(unsigned int flags, uint8_t thumbnailFactor)
{
	LOG(2, "Configuring video...");

	bool have_lores_stream = options_->lores_width && options_->lores_height;
	StreamRoles stream_roles = { StreamRole::VideoRecording };
	int lores_index = 1;
	if (!options_->no_raw)
		stream_roles.push_back(StreamRole::Raw), lores_index++;
	if (have_lores_stream)
		stream_roles.push_back(StreamRole::Viewfinder);
	configuration_ = camera_->generateConfiguration(stream_roles);
	if (!configuration_)
		throw std::runtime_error("failed to generate video configuration");

	// Now we get to override any of the default settings from the options_->
	StreamConfiguration &cfg = configuration_->at(0);
	cfg.pixelFormat = libcamera::formats::BGR161616;
	cfg.bufferCount = 6; // 6 buffers is better than 4

[naushir]

The RGB48 format is supported in all configurations. It's likely you have not updated your kernel, so the driver does not report support for 48-bpp yet, hence your error.

You can either rebuild the kernel yourself, or run sudo rpi-update to get the latest non-stable version to test out.