From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
To: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: kernel@collabora.com,
Nicolas Dufresne <nicolas.dufresne@collabora.com>,
linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 3/5] docs: uapi: media: Add common documentation of tiled NV15
Date: Fri, 4 Aug 2023 15:27:35 -0400 [thread overview]
Message-ID: <20230804192737.19016-4-nicolas.dufresne@collabora.com> (raw)
In-Reply-To: <20230804192737.19016-1-nicolas.dufresne@collabora.com>
This way we don't have to repeat over and over how the pixels are
packed in NV15.
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
.../media/v4l/pixfmt-yuv-planar.rst | 79 ++++++++++++++++---
1 file changed, 68 insertions(+), 11 deletions(-)
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
index 1d43532095c0..052927bd9396 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
@@ -373,10 +373,74 @@ two non-contiguous planes.
Tiled NV15
----------
-``V4L2_PIX_FMT_NV15_4L4`` Semi-planar 10-bit YUV 4:2:0 formats, using 4x4 tiling.
-All components are packed without any padding between each other.
-As a side-effect, each group of 4 components are stored over 5 bytes
-(YYYY or UVUV = 4 * 10 bits = 40 bits = 5 bytes).
+Semi-planar 10-bit YUV 4:2:0 formats. All components are packed
+without any padding between each other. Each pixels occupy 15 bits
+and are usually stored in group of 4 components stored over 5 bytes
+(YYYY or UVUV = 4 * 10 bits = 40 bits = 5 bytes) or partitioned into
+upper 8 bit and lower 2 bits.
+
+.. flat-table:: Sample of 4 NV15 luma pixels
+ :header-rows: 2
+ :stub-columns: 0
+
+ * -
+ - 8
+ - 7
+ - 6
+ - 5
+ - 4
+ - 3
+ - 2
+ - 1
+ - 0
+ * - byte 0
+ - Y'\ :sub:`0:0`
+ - Y'\ :sub:`0:1`
+ - Y'\ :sub:`0:2`
+ - Y'\ :sub:`0:3`
+ - Y'\ :sub:`0:4`
+ - Y'\ :sub:`0:5`
+ - Y'\ :sub:`0:6`
+ - Y'\ :sub:`0:7`
+ * - byte 1
+ - Y'\ :sub:`0:8`
+ - Y'\ :sub:`0:9`
+ - Y'\ :sub:`1:0`
+ - Y'\ :sub:`1:1`
+ - Y'\ :sub:`1:2`
+ - Y'\ :sub:`1:3`
+ - Y'\ :sub:`1:4`
+ - Y'\ :sub:`1:5`
+ * - byte 2
+ - Y'\ :sub:`1:6`
+ - Y'\ :sub:`1:7`
+ - Y'\ :sub:`1:8`
+ - Y'\ :sub:`1:9`
+ - Y'\ :sub:`2:0`
+ - Y'\ :sub:`2:1`
+ - Y'\ :sub:`2:2`
+ - Y'\ :sub:`2:3`
+ * - byte 3
+ - Y'\ :sub:`2:4`
+ - Y'\ :sub:`2:5`
+ - Y'\ :sub:`2:6`
+ - Y'\ :sub:`2:7`
+ - Y'\ :sub:`2:8`
+ - Y'\ :sub:`2:9`
+ - Y'\ :sub:`3:0`
+ - Y'\ :sub:`3:1`
+ * - byte 4
+ - Y'\ :sub:`3:2`
+ - Y'\ :sub:`3:3`
+ - Y'\ :sub:`3:4`
+ - Y'\ :sub:`3:5`
+ - Y'\ :sub:`3:6`
+ - Y'\ :sub:`3:7`
+ - Y'\ :sub:`3:8`
+ - Y'\ :sub:`3:9`
+
+``V4L2_PIX_FMT_NV15_4L4`` stores pixels in 4x4 tiles, and stores tiles linearly
+in memory.
``V4L2_PIX_FMT_NV12M_10BE_8L128`` is similar to ``V4L2_PIX_FMT_NV12M`` but stores
10 bits pixels in 2D 8x128 tiles, and stores tiles linearly in memory.
@@ -385,13 +449,6 @@ The image height must be aligned to a multiple of 128.
The layouts of the luma and chroma planes are identical.
Note the tile size is 8bytes multiplied by 128 bytes,
it means that the low bits and high bits of one pixel may be in different tiles.
-The 10 bit pixels are packed, so 5 bytes contain 4 10-bit pixels layout like
-this (for luma):
-byte 0: Y0(bits 9-2)
-byte 1: Y0(bits 1-0) Y1(bits 9-4)
-byte 2: Y1(bits 3-0) Y2(bits 9-6)
-byte 3: Y2(bits 5-0) Y3(bits 9-8)
-byte 4: Y3(bits 7-0)
``V4L2_PIX_FMT_NV12_10BE_8L128`` is similar to ``V4L2_PIX_FMT_NV12M_10BE_8L128`` but stores
two planes in one memory.
--
2.40.1
next prev parent reply other threads:[~2023-08-04 19:28 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20230804192737.19016-1-nicolas.dufresne@collabora.com>
2023-08-04 19:27 ` [PATCH 1/5] docs: uapi: media: Properly locate NV12MT diagram Nicolas Dufresne
2023-08-07 11:22 ` Andrzej Pietrasiewicz
2023-08-04 19:27 ` [PATCH 2/5] docs: uapi: media: Move NV12_10BE_8L128 to NV15 section Nicolas Dufresne
2023-08-07 11:28 ` Andrzej Pietrasiewicz
2023-08-04 19:27 ` Nicolas Dufresne [this message]
2023-08-07 11:37 ` [PATCH 3/5] docs: uapi: media: Add common documentation of tiled NV15 Andrzej Pietrasiewicz
2023-09-13 18:11 ` Nicolas Dufresne
2023-08-04 19:27 ` [PATCH 4/5] docs: uapi: media: Add a layout diagram for MT2110T Nicolas Dufresne
2023-08-07 18:40 ` Andrzej Pietrasiewicz
2023-08-07 19:29 ` Nicolas Dufresne
2023-08-07 21:24 ` Nicolas Dufresne
2023-08-08 11:46 ` Andrzej Pietrasiewicz
2023-08-04 19:27 ` [PATCH 5/5] docs: uapi: media: Document Mediatek 10bit tiled formats Nicolas Dufresne
2023-08-07 18:35 ` Andrzej Pietrasiewicz
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230804192737.19016-4-nicolas.dufresne@collabora.com \
--to=nicolas.dufresne@collabora.com \
--cc=kernel@collabora.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=mchehab@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®