Hi Hans
Thanks for the quick reply.
On Mon, 11 Oct 2021 at 17:40, Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 08/10/2021 12:30, dillon.minfei@xxxxxxxxx wrote:
> > From: Dillon Min <dillon.minfei@xxxxxxxxx>
> >
> > - add V4L2_COLORFX_SET_ARGB color effects control.
> > - add V4L2_CID_COLORFX_ARGB for ARGB color setting.
> >
> > Signed-off-by: Dillon Min <dillon.minfei@xxxxxxxxx>
> > ---
> > v3: according to Hans's suggestion, thanks.
> > - remove old stm32 private R2M ioctl
> > - add V4L2_CID_COLORFX_ARGB
> > - add V4L2_COLORFX_SET_ARGB
> >
> > Documentation/userspace-api/media/v4l/control.rst | 8 ++++++++
> > drivers/media/v4l2-core/v4l2-ctrls-defs.c | 2 ++
> > include/uapi/linux/v4l2-controls.h | 4 +++-
> > 3 files changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/userspace-api/media/v4l/control.rst b/Documentation/userspace-api/media/v4l/control.rst
> > index f8d0b923da20..319606a6288f 100644
> > --- a/Documentation/userspace-api/media/v4l/control.rst
> > +++ b/Documentation/userspace-api/media/v4l/control.rst
> > @@ -242,8 +242,16 @@ Control IDs
> > * - ``V4L2_COLORFX_SET_CBCR``
> > - The Cb and Cr chroma components are replaced by fixed coefficients
> > determined by ``V4L2_CID_COLORFX_CBCR`` control.
> > + * - ``V4L2_COLORFX_SET_ARGB``
> > + - ARGB colors.
>
> How about:
>
> - The ARGB components are replaced by the fixed ARGB components
> determined by ``V4L2_CID_COLORFX_ARGB`` control.
Sure, will be addressed by v4.
>
> I also wonder if it makes sense to include the alpha channel here.
>
> Looking at the driver code it appears to me (I might be wrong) that the alpha
> channel is never touched (DMA2D_ALPHA_MODE_NO_MODIF), and setting the alpha
> channel as part of a color effects control is rather odd as well.
Indeed, Alpha channel is not used in current code. I'll remove this item in v4.
how about change the code like below:
* - ``V4L2_COLORFX_SET_RGB``
- The RGB components are replaced by the fixed RGB components
determined by ``V4L2_CID_COLORFX_RGB`` control.
``V4L2_CID_COLORFX_RGB`` ``(integer)``
Determines the Red, Green, and Blue coefficients for
``V4L2_COLORFX_SET_RGB`` color effect.
Bits [7:0] of the supplied 32 bit value are interpreted as Blue component,
bits [15:8] as Green component, bits [23:16] as Red component, and
bits [31:24] must be zero.
>
> Alpha channel manipulation really is separate from the color and - if needed - should
> be done with a separate control.
OK, Will use a separate control when adding blend features.
Best Regards,
Dillon
>
> Regards,
>
> Hans
>
> >
> >
> > +``V4L2_CID_COLORFX_ARGB`` ``(integer)``
> > + Determines the Alpha, Red, Green, and Blue coefficients for
> > + ``V4L2_COLORFX_SET_ARGB`` color effect.
> > + Bits [7:0] of the supplied 32 bit value are interpreted as Blue component,
> > + bits [15:8] as Green component, bits [23:16] as Red component, and
> > + bits [31:24] as Alpha component.
> >
> > ``V4L2_CID_COLORFX_CBCR`` ``(integer)``
> > Determines the Cb and Cr coefficients for ``V4L2_COLORFX_SET_CBCR``
> > diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > index 421300e13a41..53be6aadb289 100644
> > --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > @@ -785,6 +785,7 @@ const char *v4l2_ctrl_get_name(u32 id)
> > case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT: return "Min Number of Output Buffers";
> > case V4L2_CID_ALPHA_COMPONENT: return "Alpha Component";
> > case V4L2_CID_COLORFX_CBCR: return "Color Effects, CbCr";
> > + case V4L2_CID_COLORFX_ARGB: return "Color Effects, ARGB";
> >
> > /*
> > * Codec controls
> > @@ -1392,6 +1393,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
> > *min = *max = *step = *def = 0;
> > break;
> > case V4L2_CID_BG_COLOR:
> > + case V4L2_CID_COLORFX_ARGB:
> > *type = V4L2_CTRL_TYPE_INTEGER;
> > *step = 1;
> > *min = 0;
> > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > index 5532b5f68493..2876c2282a68 100644
> > --- a/include/uapi/linux/v4l2-controls.h
> > +++ b/include/uapi/linux/v4l2-controls.h
> > @@ -128,6 +128,7 @@ enum v4l2_colorfx {
> > V4L2_COLORFX_SOLARIZATION = 13,
> > V4L2_COLORFX_ANTIQUE = 14,
> > V4L2_COLORFX_SET_CBCR = 15,
> > + V4L2_COLORFX_SET_ARGB = 16,
> > };
> > #define V4L2_CID_AUTOBRIGHTNESS (V4L2_CID_BASE+32)
> > #define V4L2_CID_BAND_STOP_FILTER (V4L2_CID_BASE+33)
> > @@ -145,9 +146,10 @@ enum v4l2_colorfx {
> >
> > #define V4L2_CID_ALPHA_COMPONENT (V4L2_CID_BASE+41)
> > #define V4L2_CID_COLORFX_CBCR (V4L2_CID_BASE+42)
> > +#define V4L2_CID_COLORFX_ARGB (V4L2_CID_BASE+43)
> >
> > /* last CID + 1 */
> > -#define V4L2_CID_LASTP1 (V4L2_CID_BASE+43)
> > +#define V4L2_CID_LASTP1 (V4L2_CID_BASE+44)
> >
> > /* USER-class private control IDs */
> >
> >
>
