[PATCH v2 4/4] apps: cam: sdl_sink: Support more single-plane formats

[Barnabás Pőcze]

Hi


2025. 04. 25. 14:45 keltezéssel, Laurent Pinchart írta:
> Hi Barnabás,
> 
> Thank you for the patch.
> 
> On Fri, Apr 25, 2025 at 12:47:03PM +0200, Barnabás Pőcze wrote:
>> With the newly introduced `SDLTexture1Plane` it is easy to handle
>> any single-plane format that has an SDL equivalent. So use it for
>> more YUV and RGB formats.
>>
>> The mapping of RGB formats is not entirely straightforward because
>> `SDL_PIXELFORMAT_ZZZ...888...` defines a format where the order of
>> the components is endian dependent, while libcamera's `ZZZ...888...`
>> formats are derived from the matching DRM formats, and the RGB formats
>> in question are defined to be little-endian there. So the
>> endian-independent `SDL_PIXELFORMAT_{ZZZ24,ZZZZ32}` are used.
> 
> Format mapping is always painful :-(
> 
>> Signed-off-by: Barnabás Pőcze <barnabas.pocze at ideasonboard.com>
>> ---
>>   src/apps/cam/sdl_sink.cpp | 36 ++++++++++++++++++++++++++++++++++++
>>   1 file changed, 36 insertions(+)
>>
>> diff --git a/src/apps/cam/sdl_sink.cpp b/src/apps/cam/sdl_sink.cpp
>> index b295675dc..2edbb523d 100644
>> --- a/src/apps/cam/sdl_sink.cpp
>> +++ b/src/apps/cam/sdl_sink.cpp
>> @@ -77,6 +77,42 @@ int SDLSink::configure(const libcamera::CameraConfiguration &config)
>>   	case libcamera::formats::YUYV:
>>   		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_YUY2, cfg.stride);
>>   		break;
>> +	case libcamera::formats::UYVY:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_UYVY, cfg.stride);
>> +		break;
>> +	case libcamera::formats::YVYU:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_YVYU, cfg.stride);
>> +		break;
>> +	case libcamera::formats::ARGB8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_BGRA32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::XRGB8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_BGRX32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::RGBA8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_ABGR32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::RGBX8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_XBGR32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::ABGR8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_RGBA32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::XBGR8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_RGBX32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::BGRA8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_ARGB32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::BGRX8888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_XRGB32, cfg.stride);
>> +		break;
>> +	case libcamera::formats::RGB888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_BGR24, cfg.stride);
>> +		break;
>> +	case libcamera::formats::BGR888:
>> +		texture_ = std::make_unique<SDLTexture1Plane>(rect_, SDL_PIXELFORMAT_RGB24, cfg.stride);
>> +		break;
> 
> I'm tempted to avoid all the constructor calls by instead adding a
> sdlFormat variable and filling it in the switch, and then creating the
> texture after the switch.

Yes, indeed, and I had thought about that for a bit, but there is also
SDLTextureNV12 (conditionally), and I didn't really see a good way to
reconcile the two.


Regards,
Barnabás Pőcze

> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> 
>>   	default:
>>   		std::cerr << "Unsupported pixel format "
>>   			  << cfg.pixelFormat.toString() << std::endl;
>