[libcamera-devel] [PATCH v4 05/32] ipa: libipa: Provide a common base for frame contexts

[Laurent Pinchart]

On Tue, Sep 20, 2022 at 02:40:28PM +0100, Kieran Bingham wrote:
> Quoting Laurent Pinchart (2022-09-08 02:41:33)
> > From: Kieran Bingham <kieran.bingham at ideasonboard.com>
> > 
> > Provide a common FrameContext as a base for IPA modules to inherit from.
> > 
> > This will allow having a common set of parameters for every frame
> > context managed by the FCQueue implementation.
> > 
> > Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 
> Missing SoB.
> > ---
> > Changes since v3:
> > 
> > - Rename structure from IPAFrameContext to FrameContext
> > - Move changes to IPA modules to separate patches
> > - Make the FrameContext::frame member private
> > ---
> >  src/ipa/libipa/fc_queue.cpp | 18 ++++++++++++++++++
> >  src/ipa/libipa/fc_queue.h   | 10 ++++++++++
> >  2 files changed, 28 insertions(+)
> > 
> > diff --git a/src/ipa/libipa/fc_queue.cpp b/src/ipa/libipa/fc_queue.cpp
> > index b81d497e255a..8f61c85131c9 100644
> > --- a/src/ipa/libipa/fc_queue.cpp
> > +++ b/src/ipa/libipa/fc_queue.cpp
> > @@ -20,6 +20,24 @@ namespace ipa {
> >   * \brief Queue to access per-frame Context
> >   */
> >  
> > +/**
> > + * \struct FrameContext
> > + * \brief Context for a frame
> > + *
> > + * The frame context stores data specific to a single frame processed by the
> > + * IPA. Each frame processed by the IPA has a context associated with it,
> > + * accessible through the Frame Context Queue.
> > + *
> > + * Fields in the frame context should reflect values and controls associated
> > + * with the specific frame as requested by the application, and as configured by
> > + * the hardware. Fields can be read by algorithms to determine if they should
> > + * update any specific action for this frame, and finally to update the metadata
> > + * control lists when the frame is fully completed.
> > + *
> > + * \var FrameContext::frame
> > + * \brief The frame number
> > + */
> > +
> >  /**
> >   * \class FCQueue
> >   * \brief A support class for queueing FrameContext instances through the IPA
> > diff --git a/src/ipa/libipa/fc_queue.h b/src/ipa/libipa/fc_queue.h
> > index 0f3af0f3a189..d8a5b8297a70 100644
> > --- a/src/ipa/libipa/fc_queue.h
> > +++ b/src/ipa/libipa/fc_queue.h
> > @@ -8,6 +8,7 @@
> >  #pragma once
> >  
> >  #include <algorithm>
> > +#include <stdint.h>
> >  #include <vector>
> >  
> >  #include <libcamera/base/log.h>
> > @@ -18,6 +19,15 @@ LOG_DECLARE_CATEGORY(FCQueue)
> >  
> >  namespace ipa {
> >  
> > +template<typename FrameContext>
> > +class FCQueue;
> > +
> > +struct FrameContext {
> > +private:
> > +       template<typename T> friend class FCQueue;
> > +       uint32_t frame;
> 
> Seems fine to me.
> 
> I'm still not sure what else is going to end up in here. There's a
> chance that we might need to store the incoming Request ControlList (or
> a copy of) ... so I still think there's sufficient requirement for the
> common base type.

I haven't found a need for storing additional data in the base class in
the RkISP1 IPA. We'll see.

> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 
> > +};
> > +
> >  template<typename FrameContext>
> >  class FCQueue
> >  {

-- 
Regards,

Laurent Pinchart