The format is used on the R-Car VSP1 video queues that carry 2-D histogram statistics data. Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx> --- Documentation/media/uapi/v4l/meta-formats.rst | 1 + .../media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst | 122 +++++++++++++++++++++ drivers/media/v4l2-core/v4l2-ioctl.c | 1 + include/uapi/linux/videodev2.h | 3 +- 4 files changed, 126 insertions(+), 1 deletion(-) create mode 100644 Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst diff --git a/Documentation/media/uapi/v4l/meta-formats.rst b/Documentation/media/uapi/v4l/meta-formats.rst index 05ab91e..01e24e3 100644 --- a/Documentation/media/uapi/v4l/meta-formats.rst +++ b/Documentation/media/uapi/v4l/meta-formats.rst @@ -13,3 +13,4 @@ These formats are used for the :ref:`metadata` interface only. :maxdepth: 1 pixfmt-meta-vsp1-hgo + pixfmt-meta-vsp1-hgt diff --git a/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst b/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst new file mode 100644 index 0000000..0393148 --- /dev/null +++ b/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst @@ -0,0 +1,122 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _v4l2-meta-fmt-vsp1-hgt: + +******************************* +V4L2_META_FMT_VSP1_HGT ('VSPT') +******************************* + +*man V4L2_META_FMT_VSP1_HGT(2)* + +Renesas R-Car VSP1 2-D Histogram Data + + +Description +=========== + +This format describes histogram data generated by the Renesas R-Car VSP1 +2-D Histogram (HGT) engine. + +The VSP1 HGT is a histogram computation engine that operates on HSV +data. It operates on a possibly cropped and subsampled input image and +computes the sum, maximum and minimum of the S component as well as a +weighted frequency histogram based on the H and S components. + +The histogram is a matrix of 6 Hue and 32 Saturation buckets, 192 in +total. Each HSV value is added to one or more buckets with a weight +between 1 and 16 depending on the Hue areas configuration. Finding the +corresponding buckets is done by inspecting the H and S value independently. + +The Saturation position **n** (0 - 31) of the bucket in the matrix is +found by the expression: + + n = S / 8 + +The Hue position **m** (0 - 5) of the bucket in the matrix depends on +how the HGT Hue areas are configured. There are 6 user configurable Hue +Areas which can be configured to cover overlapping Hue values: + +:: + + Area 0 Area 1 Area 2 Area 3 Area 4 Area 5 + ________ ________ ________ ________ ________ ________ + \ /| |\ /| |\ /| |\ /| |\ /| |\ /| |\ / + \ / | | \ / | | \ / | | \ / | | \ / | | \ / | | \ / + X | | X | | X | | X | | X | | X | | X + / \ | | / \ | | / \ | | / \ | | / \ | | / \ | | / \ + / \| |/ \| |/ \| |/ \| |/ \| |/ \| |/ \ + 5U 0L 0U 1L 1U 2L 2U 3L 3U 4L 4U 5L 5U 0L + <0..............................Hue Value............................255> + +When two consecutive areas don't overlap (n+1L is equal to nU) the boundary +value is considered as part of the lower area. + +Pixels with a hue value included in the centre of an area (between nL and nU +included) are are attributed to that single area and given a weight of 16. +Pixels with a hue value included in the overlapping region between two areas +(between n+1L and nU excluded) are attributed to both areas and given a weight +for each of these areas proportional to their position along the diagonal +lines (rounded down)." + +The Hue area setup must match one of the following constrains: + +:: + + 0L <= 0U <= 1L <= 1U <= 2L <= 2U <= 3L <= 3U <= 4L <= 4U <= 5L <= 5U + +:: + + 0U <= 1L <= 1U <= 2L <= 2U <= 3L <= 3U <= 4L <= 4U <= 5L <= 5U <= 0L + +**Byte Order.** +All data is stored in memory in little endian format. Each cell in the tables +contains one byte. + +.. flat-table:: VSP1 HGT Data - (776 bytes) + :header-rows: 2 + :stub-columns: 0 + + * - Offset + - :cspan:`4` Memory + * - + - [31:24] + - [23:16] + - [15:8] + - [7:0] + * - 0 + - - + - S max [7:0] + - - + - S min [7:0] + * - 4 + - :cspan:`4` S sum [31:0] + * - 8 + - :cspan:`4` Histogram bucket (m=0, n=0) [31:0] + * - 12 + - :cspan:`4` Histogram bucket (m=0, n=1) [31:0] + * - + - :cspan:`4` ... + * - 132 + - :cspan:`4` Histogram bucket (m=0, n=31) [31:0] + * - 136 + - :cspan:`4` Histogram bucket (m=1, n=0) [31:0] + * - + - :cspan:`4` ... + * - 264 + - :cspan:`4` Histogram bucket (m=2, n=0) [31:0] + * - + - :cspan:`4` ... + * - 392 + - :cspan:`4` Histogram bucket (m=3, n=0) [31:0] + * - + - :cspan:`4` ... + * - 520 + - :cspan:`4` Histogram bucket (m=4, n=0) [31:0] + * - + - :cspan:`4` ... + * - 648 + - :cspan:`4` Histogram bucket (m=5, n=0) [31:0] + * - + - :cspan:`4` ... + * - 772 + - :cspan:`4` Histogram bucket (m=5, n=31) [31:0] diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index b7f7d5f..f459c4f 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -1259,6 +1259,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt) case V4L2_SDR_FMT_CS14LE: descr = "Complex S14LE"; break; case V4L2_SDR_FMT_RU12LE: descr = "Real U12LE"; break; case V4L2_META_FMT_VSP1_HGO: descr = "R-Car VSP1 1-D Histogram"; break; + case V4L2_META_FMT_VSP1_HGT: descr = "R-Car VSP1 2-D Histogram"; break; default: /* Compressed formats */ diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 1dbe52a..c8c046c 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -638,7 +638,8 @@ struct v4l2_pix_format { #define V4L2_SDR_FMT_RU12LE v4l2_fourcc('R', 'U', '1', '2') /* real u12le */ /* Meta-data formats */ -#define V4L2_META_FMT_VSP1_HGO v4l2_fourcc('V', 'S', 'P', 'H') /* R-Car VSP1 Histogram */ +#define V4L2_META_FMT_VSP1_HGO v4l2_fourcc('V', 'S', 'P', 'H') /* R-Car VSP1 1-D Histogram */ +#define V4L2_META_FMT_VSP1_HGT v4l2_fourcc('V', 'S', 'P', 'T') /* R-Car VSP1 2-D Histogram */ /* priv field value to indicates that subsequent fields are valid. */ #define V4L2_PIX_FMT_PRIV_MAGIC 0xfeedcafe -- 2.9.3