[libcamera-devel] [PATCH v2 01/17] libcamera: ipu3: Use the optimal sensor size

[Jacopo Mondi]

Sorry I forgot to reply to this one

On Wed, Sep 22, 2021 at 04:51:26AM +0300, Laurent Pinchart wrote:
> Hi Jacopo,
>
> Thank you for the patch.
>
> (Resending with Umang's correct e-mail address now)
>
> On Tue, Sep 07, 2021 at 09:40:51PM +0200, Jacopo Mondi wrote:
> > As reported by commit 7208e70211a6 ("libcamera: ipu3: Always use sensor
> > full frame size") the current implementation of the IPU3 pipeline
> > handler always uses the sensor resolution as the ImgU input frame size in
> > order to work around an issue with the ImgU configuration procedure.
> >
> > Now that the frame selection policy has been modified in the CIO2Device
> > class implementation to comply with the requirements of the ImgU
> > configuration script we can remove the workaround and select the most
> > opportune sensor size to feed the ImgU with.
>
> On a side note, I missed reviewing the changes in cio2.cpp, doesn't that
> belong to ipu3.cpp instead ?
>

$ git show 5fc426fbfe58a82e30021d7a9ca12a4daeaec0f3 --stat
 src/libcamera/pipeline/ipu3/cio2.cpp | 8 ++++++++


> > Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> > Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>
> > Reviewed-by: Umang Jain <umang.jain at ideasonboard.com>
> > ---
> >  src/libcamera/pipeline/ipu3/ipu3.cpp | 41 ++++++++++++++++------------
> >  1 file changed, 23 insertions(+), 18 deletions(-)
> >
> > diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
> > index c287bf86e79a..291338288685 100644
> > --- a/src/libcamera/pipeline/ipu3/ipu3.cpp
> > +++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
> > @@ -229,7 +229,16 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
> >  		status = Adjusted;
> >  	}
> >
> > -	/* Validate the requested stream configuration */
> > +	/*
> > +	 * Validate the requested stream configuration and select the sensor
> > +	 * format by collecting the maximum RAW stream width and height and
> > +	 * picking the closest larger match.
> > +	 *
> > +	 * If no RAW stream is requested use the one of the largest YUV stream,
> > +	 * plus margin pixels for the IF and BDS rectangle to downscale.
> > +	 *
> > +	 * \todo Clarify the IF and BDS margins requirements.
> > +	 */
> >  	unsigned int rawCount = 0;
> >  	unsigned int yuvCount = 0;
> >  	Size maxYuvSize;
> > @@ -240,7 +249,7 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
> >
> >  		if (info.colourEncoding == PixelFormatInfo::ColourEncodingRAW) {
> >  			rawCount++;
> > -			rawSize = cfg.size;
> > +			rawSize.expandTo(cfg.size);
>
> We support a single raw stream only, is this change needed ?
>

It makes the two branches look the same

> >  		} else {
> >  			yuvCount++;
> >  			maxYuvSize.expandTo(cfg.size);
> > @@ -269,24 +278,20 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
> >  	/*
> >  	 * Generate raw configuration from CIO2.
> >  	 *
> > -	 * \todo The image sensor frame size should be selected to optimize
> > -	 * operations based on the sizes of the requested streams. However such
> > -	 * a selection makes the pipeline configuration procedure fail for small
> > -	 * resolutions (for example: 640x480 with OV5670) and causes the capture
> > -	 * operations to stall for some stream size combinations (see the
> > -	 * commit message of the patch that introduced this comment for more
> > -	 * failure examples).
> > +	 * The output YUV streams will be limited in size to the
> > +	 * maximum frame size requested for the RAW stream, if present.
>
> This could be reflowed.
>
> >  	 *
> > -	 * Until the sensor frame size calculation criteria are clarified, when
> > -	 * capturing from ImgU always use the largest possible size which
> > -	 * guarantees better results at the expense of the frame rate and CSI-2
> > -	 * bus bandwidth. When only a raw stream is requested use the requested
> > -	 * size instead, as the ImgU is not involved.
> > +	 * If no raw stream is requested generate a size as large as the maximum
> > +	 * requested YUV size aligned to the ImgU constraints and bound by the
> > +	 * sensor's maximum resolution. See
> > +	 * https://bugs.libcamera.org/show_bug.cgi?id=32
> >  	 */
> > -	if (!yuvCount)
> > -		cio2Configuration_ = data_->cio2_.generateConfiguration(rawSize);
> > -	else
> > -		cio2Configuration_ = data_->cio2_.generateConfiguration({});
> > +	if (rawSize.isNull())
> > +		rawSize = maxYuvSize.alignedUpTo(40, 540)
>
> Is alignedUpTo() the right function ? It will round up the height to a
> multiple of 540, that doesn't sound right.
>

No it should probably be expandedTo()

> > +				    .alignedUpTo(IMGU_OUTPUT_WIDTH_MARGIN,
> > +						 IMGU_OUTPUT_HEIGHT_MARGIN)
>
> Same here.
>

While I guess this one is correct as we need to align up to the
margins

> > +				    .boundedTo(data_->cio2_.sensor()->resolution());
> > +	cio2Configuration_ = data_->cio2_.generateConfiguration(rawSize);
> >  	if (!cio2Configuration_.pixelFormat.isValid())
> >  		return Invalid;
> >
>
> --
> Regards,
>
> Laurent Pinchart