Hi Hans,

On Mon, 2016-08-01 at 12:39 +0200, Hans Verkuil wrote:

Hi Tiffany,

On 08/01/2016 11:38 AM, Tiffany Lin wrote:

quoted

Hi Hans,

<snip>

quoted

quoted

quoted

+static int vidioc_vdec_g_selection(struct file *file, void *priv,
+			struct v4l2_selection *s)
+{
+	struct mtk_vcodec_ctx *ctx = fh_to_ctx(priv);
+
+	if (V4L2_TYPE_IS_OUTPUT(s->type))
+		return -EINVAL;
+
+	if (s->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;

How does the cropping rectangle relate to the format size? There is no s_selection,
so this doesn't make sense.

I want to return encoded crop information or real display region that
display driver could know where is padding region.

Sorry, I don't understand this.

This is a decoder, so based on the bitstream it decodes to a certain width
and height. I assume that is what you refer to as coded_width and coded_height?

If so, then what is the 'real display region' and how does it relate to the
coded width/height?

This is probably a terminology issue but I need to understand this before I
can decide what should be done here.

We define coded_width and coded_height as frame buffer width and height.
Coded resolution is stream resolution in pixels aligned to codec format
and hardware requirements.
And we assign bytesperline as coded_width.

g_selection is for getting visible resolution for user space.
visible resolution - stream resolution of the visible picture, in
pixels, to be used for display purposes; must be smaller or equal to
coded resolution;
visible height - height for given visible resolution
visible width - width for given visible resolution

For my understand, g_fmt should return coded width/height in
pix_mp->width, pix_mp->height.
And bytesperline is coded with.
g_selection return visible width/height.
Is this understanding correct?


best regards,
Tiffany

Regards,

	Hans

quoted

User space use s_fmt/g_fmt  to set/get coded_width and coded_height, and
use g_crop to get real display region.
That's why I do not add s_selection.

quoted

Alternatively, it could be that you are really returning V4L2_SEL_TGT_COMPOSE_PADDED.

V4L2_SEL_TGT_COMPOSE_PADDED means
"The active area and all padding pixels that are inserted or modified by
hardware."
But I just want to return active area to user space.

quoted

quoted

+
+	if (ctx->state < MTK_STATE_HEADER)
+		return -EINVAL;
+
+	if ((ctx->q_data[MTK_Q_DATA_SRC].fmt->fourcc == V4L2_PIX_FMT_H264) ||
+	    (ctx->q_data[MTK_Q_DATA_SRC].fmt->fourcc == V4L2_PIX_FMT_VP8) ||
+	    (ctx->q_data[MTK_Q_DATA_SRC].fmt->fourcc == V4L2_PIX_FMT_VP9)) {
+
+		if (vdec_if_get_param(ctx, GET_PARAM_CROP_INFO, &(s->r))) {
+			mtk_v4l2_debug(2,
+					"[%d]Error!! Cannot get param : GET_PARAM_CROP_INFO ERR",
+					ctx->id);
+			s->r.left = 0;
+			s->r.top = 0;
+			s->r.width = ctx->picinfo.buf_w;
+			s->r.height = ctx->picinfo.buf_h;
+		}
+		mtk_v4l2_debug(2, "Cropping info: l=%d t=%d w=%d h=%d",
+				s->r.left, s->r.top, s->r.width,
+				s->r.height);
+	} else {
+		s->r.left = 0;
+		s->r.top = 0;
+		s->r.width = ctx->picinfo.pic_w;
+		s->r.height = ctx->picinfo.pic_h;
+		mtk_v4l2_debug(2, "Cropping info: w=%d h=%d fw=%d fh=%d",
+				s->r.width, s->r.height, ctx->picinfo.buf_w,
+				ctx->picinfo.buf_h);
+	}
+	return 0;
+}