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diff --git a/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst b/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst deleted file mode 100644 index d1a341af9c48..000000000000 --- a/Documentation/media/uapi/v4l/pixfmt-meta-vsp1-hgt.rst +++ /dev/null @@ -1,136 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -.. _v4l2-meta-fmt-vsp1-hgt: - -******************************* -V4L2_META_FMT_VSP1_HGT ('VSPT') -******************************* - -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: - -.. raw:: latex - - \small - -:: - - 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> - - -.. raw:: latex - - \normalsize - -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 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] |