Re: [PATCH v6 1/2] [media] exynos-gsc: Use user configured colorspace if provided

From: Hans Verkuil
Date: Fri Mar 10 2017 - 05:31:25 EST


On 01/03/17 12:51, Thibault Saunier wrote:
> Use colorspace provided by the user as we are only doing scaling and
> color encoding conversion, we won't be able to transform the colorspace
> itself and the colorspace won't mater in that operation.
>
> Also always use output colorspace on the capture side.
>
> If the user does not provide a colorspace do no make it up, we might
> later while processing need to figure out the colorspace, which
> is possible depending on the frame size but do not ever guess and
> leak that guess to the userspace.
>
> Signed-off-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
> Signed-off-by: Thibault Saunier <thibault.saunier@xxxxxxxxxxxxxxx>
> Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
>
> ---
>
> Changes in v6:
> - Do not ever guess colorspace
>
> Changes in v5:
> - Squash commit to always use output colorspace on the capture side
> inside this one
> - Fix typo in commit message
>
> Changes in v4:
> - Reword commit message to better back our assumptions on specifications
>
> Changes in v3:
> - Do not check values in the g_fmt functions as Andrzej explained in previous review
> - Added 'Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>'
>
> Changes in v2: None
>
> drivers/media/platform/exynos-gsc/gsc-core.c | 9 ++++-----
> drivers/media/platform/exynos-gsc/gsc-core.h | 1 +
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/exynos-gsc/gsc-core.c b/drivers/media/platform/exynos-gsc/gsc-core.c
> index 59a634201830..0241168c85af 100644
> --- a/drivers/media/platform/exynos-gsc/gsc-core.c
> +++ b/drivers/media/platform/exynos-gsc/gsc-core.c
> @@ -454,6 +454,7 @@ int gsc_try_fmt_mplane(struct gsc_ctx *ctx, struct v4l2_format *f)
> } else {
> min_w = variant->pix_min->target_rot_dis_w;
> min_h = variant->pix_min->target_rot_dis_h;
> + pix_mp->colorspace = ctx->out_colorspace;
> }
>
> pr_debug("mod_x: %d, mod_y: %d, max_w: %d, max_h = %d",
> @@ -472,10 +473,8 @@ int gsc_try_fmt_mplane(struct gsc_ctx *ctx, struct v4l2_format *f)
>
> pix_mp->num_planes = fmt->num_planes;
>
> - if (pix_mp->width >= 1280) /* HD */
> - pix_mp->colorspace = V4L2_COLORSPACE_REC709;
> - else /* SD */
> - pix_mp->colorspace = V4L2_COLORSPACE_SMPTE170M;
> + if (V4L2_TYPE_IS_OUTPUT(f->type))
> + ctx->out_colorspace = pix_mp->colorspace;
>
> for (i = 0; i < pix_mp->num_planes; ++i) {
> struct v4l2_plane_pix_format *plane_fmt = &pix_mp->plane_fmt[i];
> @@ -519,8 +518,8 @@ int gsc_g_fmt_mplane(struct gsc_ctx *ctx, struct v4l2_format *f)
> pix_mp->height = frame->f_height;
> pix_mp->field = V4L2_FIELD_NONE;
> pix_mp->pixelformat = frame->fmt->pixelformat;
> - pix_mp->colorspace = V4L2_COLORSPACE_REC709;
> pix_mp->num_planes = frame->fmt->num_planes;
> + pix_mp->colorspace = ctx->out_colorspace;

You need to do the same for the ycbcr_enc, xfer_func and quantization fields.
With that in place it is fully 'colorspace compliant' :-)

Regards,

Hans

>
> for (i = 0; i < pix_mp->num_planes; ++i) {
> pix_mp->plane_fmt[i].bytesperline = (frame->f_width *
> diff --git a/drivers/media/platform/exynos-gsc/gsc-core.h b/drivers/media/platform/exynos-gsc/gsc-core.h
> index 696217e9af66..715d9c9d8d30 100644
> --- a/drivers/media/platform/exynos-gsc/gsc-core.h
> +++ b/drivers/media/platform/exynos-gsc/gsc-core.h
> @@ -376,6 +376,7 @@ struct gsc_ctx {
> struct v4l2_ctrl_handler ctrl_handler;
> struct gsc_ctrls gsc_ctrls;
> bool ctrls_rdy;
> + enum v4l2_colorspace out_colorspace;
> };
>
> void gsc_set_prefbuf(struct gsc_dev *gsc, struct gsc_frame *frm);
>