[libcamera-devel] [PATCH RFC 6/7] android: yuv: add YUYV -> NV12 conversion

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon Sep 25 12:56:53 CEST 2023


On Mon, Sep 25, 2023 at 01:52:40PM +0300, Tomi Valkeinen wrote:
> On 25/09/2023 00:34, Laurent Pinchart wrote:
> > Hi Mattijs,
> > 
> > Thank you for the patch.
> > 
> > On Fri, Sep 15, 2023 at 09:57:30AM +0200, Mattijs Korpershoek via libcamera-devel wrote:
> >> On am62x platforms, the receiver driver (j721e-csi2rx) only
> >> supports packed YUV422 formats such as YUYV, YVYU, UYVY and VYUY.
> >>
> >> The receiver and the sensor (ov5640) hardware are both capable of
> >> YUV420, however:
> >>
> >> * we are not aware of OV5640 being tested with YUV420 formats on any
> >>    vendor tree.
> > 
> > Are you talking about packed YUV 4:2:0 here, or planar YUV 4:2:0 ?
> > Sensors only output packed formats (there could be exceptions, but they
> > would be very rare), it is the DMA engine on the host size that would
> > convert them to planar formats. That would be the DMA engine handled by
> > the k3-udma driver. It's fairly complicated, and I don't know if it
> > would hahev the ability to output planar formats. Tomi (on CC) may have
> > more information.
> 
> No, I don't know if the CSI-2 RX or the DMA engine support packed to 
> planar conversions. Maybe Jai knows.
> 
> If the point is to show the frames on the screen, it sounds to me that 
> the YUV422 formats would work the best.

Do you mean packed YUV 4:2:2 or (a.k.a. YUYV & co), semi-planar YUV
4:2:2 (a.k.a. NV16 and NV61) or planar YUV 4:2:2 ? -)

> >> * NV12 has different line lines (even lines are twice as long as odd
> > 
> > s/lines/lengths/
> > 
> >>    lines) Different line-sized DMA transfers have not been tested on
> > 
> > s/)/)./
> > 
> >>    the TI CSI-RX SHIM IP.
> > 
> > As mentioned just above, the sensor will not output planar formats, so
> > the issue is about the
> > 
> >> On the other hand, the graphics allocator (gralloc) cannot allocate
> >> YUV422 buffers directly. It mainly allocated NV12 buffers when
> >> userspace requests HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED.
> > 
> > The DSS seems to support YUYV, is there a way to fix the TI gralloc to
> > support it ?
> > 
> >> Because of the above, we need a pixel conversion from YUYV to NV12,
> >> which is handled in the yuv processor via libyuv.
> >>
> >> Signed-off-by: Mattijs Korpershoek <mkorpershoek at baylibre.com>
> >> ---
> >>   src/android/yuv/post_processor_yuv.cpp | 91 +++++++++++++++++++++++++---------
> >>   1 file changed, 68 insertions(+), 23 deletions(-)
> >>
> >> diff --git a/src/android/yuv/post_processor_yuv.cpp b/src/android/yuv/post_processor_yuv.cpp
> >> index 734bb85b7351..b680b833dafb 100644
> >> --- a/src/android/yuv/post_processor_yuv.cpp
> >> +++ b/src/android/yuv/post_processor_yuv.cpp
> >> @@ -7,6 +7,9 @@
> >>   
> >>   #include "post_processor_yuv.h"
> >>   
> >> +#include <utility>
> >> +
> >> +#include <libyuv/convert.h>
> >>   #include <libyuv/scale.h>
> >>   
> >>   #include <libcamera/base/log.h>
> >> @@ -22,14 +25,42 @@ using namespace libcamera;
> >>   
> >>   LOG_DEFINE_CATEGORY(YUV)
> >>   
> >> +namespace {
> >> +
> >> +/**
> >> + * \var supportedConversions
> >> + * \brief list of supported output pixel formats for an input pixel format
> >> + */
> >> +const std::map<PixelFormat, const std::vector<PixelFormat>> supportedConversions = {
> >> +	{ formats::YUYV, { formats::NV12 } },
> >> +};
> >> +
> >> +} /* namespace */
> >> +
> >>   int PostProcessorYuv::configure(const StreamConfiguration &inCfg,
> >>   				const StreamConfiguration &outCfg)
> >>   {
> >>   	if (inCfg.pixelFormat != outCfg.pixelFormat) {
> >> -		LOG(YUV, Error) << "Pixel format conversion is not supported"
> >> -				<< " (from " << inCfg.pixelFormat
> >> -				<< " to " << outCfg.pixelFormat << ")";
> >> -		return -EINVAL;
> >> +		const auto it = supportedConversions.find(inCfg.pixelFormat);
> >> +		if (it == supportedConversions.end()) {
> >> +			LOG(YUV, Error) << "Unsupported source format " << inCfg.pixelFormat;
> > 
> > 			LOG(YUV, Error)
> > 				<< "Unsupported source format "
> > 				<< inCfg.pixelFormat;
> > 
> >> +			return -EINVAL;
> >> +		}
> >> +
> >> +		std::vector<PixelFormat> outFormats = it->second;
> > 
> > No need for a copy.
> > 
> >> +		const auto &match = std::find(outFormats.begin(), outFormats.end(), outCfg.pixelFormat);
> > 
> > 		const auto &match = std::find(outFormats.begin(), outFormats.end(),
> > 					      outCfg.pixelFormat);
> > 
> >> +		if (match == outFormats.end()) {
> >> +			LOG(YUV, Error) << "Requested pixel format conversion is not supported"
> >> +					<< " (from " << inCfg.pixelFormat
> >> +					<< " to " << outCfg.pixelFormat << ")";
> > 
> > 			LOG(YUV, Error)
> > 				<< "Requested pixel format conversion is not supported"
> > 				<< " (from " << inCfg.pixelFormat
> > 				<< " to " << outCfg.pixelFormat << ")";
> > 
> >> +			return -EINVAL;
> >> +		}
> >> +	} else {
> >> +		if (inCfg.pixelFormat != formats::NV12) {
> >> +			LOG(YUV, Error) << "Unsupported format " << inCfg.pixelFormat
> >> +					<< " (only NV12 is supported for scaling)";
> > 
> > 			LOG(YUV, Error)
> > 				<< "Unsupported format " << inCfg.pixelFormat
> > 				<< " (only NV12 is supported for scaling)";
> > 
> >> +			return -EINVAL;
> >> +		}
> >>   	}
> >>   
> >>   	if (inCfg.size < outCfg.size) {
> >> @@ -39,12 +70,6 @@ int PostProcessorYuv::configure(const StreamConfiguration &inCfg,
> >>   		return -EINVAL;
> >>   	}
> >>   
> >> -	if (inCfg.pixelFormat != formats::NV12) {
> >> -		LOG(YUV, Error) << "Unsupported format " << inCfg.pixelFormat
> >> -				<< " (only NV12 is supported)";
> >> -		return -EINVAL;
> >> -	}
> >> -
> >>   	calculateLengths(inCfg, outCfg);
> >>   	return 0;
> >>   }
> >> @@ -66,20 +91,40 @@ void PostProcessorYuv::process(Camera3RequestDescriptor::StreamBuffer *streamBuf
> >>   		return;
> >>   	}
> >>   
> >> -	int ret = libyuv::NV12Scale(sourceMapped.planes()[0].data(),
> >> -				    sourceStride_[0],
> >> -				    sourceMapped.planes()[1].data(),
> >> -				    sourceStride_[1],
> >> -				    sourceSize_.width, sourceSize_.height,
> >> -				    destination->plane(0).data(),
> >> -				    destinationStride_[0],
> >> -				    destination->plane(1).data(),
> >> -				    destinationStride_[1],
> >> -				    destinationSize_.width,
> >> -				    destinationSize_.height,
> >> -				    libyuv::FilterMode::kFilterBilinear);
> >> +	int ret = 0;
> >> +	switch (sourceFormat_) {
> >> +	case formats::NV12:
> >> +		ret = libyuv::NV12Scale(sourceMapped.planes()[0].data(),
> >> +					sourceStride_[0],
> >> +					sourceMapped.planes()[1].data(),
> >> +					sourceStride_[1],
> >> +					sourceSize_.width, sourceSize_.height,
> >> +					destination->plane(0).data(),
> >> +					destinationStride_[0],
> >> +					destination->plane(1).data(),
> >> +					destinationStride_[1],
> >> +					destinationSize_.width,
> >> +					destinationSize_.height,
> >> +					libyuv::FilterMode::kFilterBilinear);
> >> +		break;
> >> +	case formats::YUYV:
> >> +		ret = libyuv::YUY2ToNV12(sourceMapped.planes()[0].data(),
> >> +					 sourceStride_[0],
> >> +					 destination->plane(0).data(),
> >> +					 destinationStride_[0],
> >> +					 destination->plane(1).data(),
> >> +					 destinationStride_[1],
> >> +					 destinationSize_.width,
> >> +					 destinationSize_.height);
> >> +		break;
> >> +	default:
> >> +		LOG(YUV, Error) << "Unsupported source format " << sourceFormat_;
> >> +		processComplete.emit(streamBuffer, PostProcessor::Status::Error);
> >> +		break;
> > 
> > This can't happen, can it ?
> > 
> >> +	}
> >> +
> >>   	if (ret) {
> >> -		LOG(YUV, Error) << "Failed NV12 scaling: " << ret;
> >> +		LOG(YUV, Error) << "Libyuv operation failure: " << ret;
> > 
> > s/Libyuv/libyuv/
> > 
> > Although I would write "YUV post-processing failure: ".
> > 
> >>   		processComplete.emit(streamBuffer, PostProcessor::Status::Error);
> >>   		return;
> >>   	}
> >>

-- 
Regards,

Laurent Pinchart


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