Re: [PATCH v3 2/4] media: v4l2-common: Add v4l2_fill_pixfmt_aligned() helper

[Sven Püschel]

Hi Jacopo,

On 7/10/26 11:38 AM, Jacopo Mondi wrote:
> > This is due to the fact, that while we have a hdiv of 2 we also interleave
> > the cb and cr parts in a single plane, which results in the stride being the
> > same number of bytes as for the y plane (and vdiv isn't relevant for the
> > stride).
> >
> > Therefore the stride scaling also respects the bits per plane (bpp) value to
> > determine the scaling.
> >
> > @Tommaso : While the sentence looks ok, the NV12 example is misguided. The
> I guess the usage of NV12 was as example of a "formats that store
> multiple component planes in a single memory"
>
> NV24/42 works the same, but being 444 it needs the chroma plane stride to
> be a multiple of the fist plane stride and might prove as a better
> example ?
My potential concern is that NV as an example misguides the reader into 
one of the following:

- It's only for formats which interleave cb/cr into one plane (whereas 
YUV420 also gets scaled)
- NV24 in the example being though of including the NV24M variant 
(whereas latter won't be affected)

Maybe smth. like YUV420 but not YUV420M is a better example (could also 
be NV24 but not NV24M)?

Sincerely
    Sven