[v5,2/7] v4l2: add support for colorspace conversion API (CSC) for video capture
diff mbox series

Message ID 20200703171019.19270-3-dafna.hirschfeld@collabora.com
State New
Headers show
Series
  • v4l2: add support for colorspace conversion API (CSC) for video capture and subdevices
Related show

Commit Message

Dafna Hirschfeld July 3, 2020, 5:10 p.m. UTC
For video capture it is the driver that reports the colorspace,
Y'CbCr/HSV encoding, quantization range and transfer function
used by the video, and there is no way to request something
different, even though many HDTV receivers have some sort of
colorspace conversion capabilities.

For output video this feature already exists since the application
specifies this information for the video format it will send out, and
the transmitter will enable any available CSC if a format conversion has
to be performed in order to match the capabilities of the sink.

For video capture we propose adding new v4l2_pix_format flag:
V4L2_PIX_FMT_FLAG_SET_CSC. The flag is set by the application,
the driver will interpret the colorspace, ycbcr_enc/hsv_enc, quantization
and xfer_func fields as the requested colorspace information and will
attempt to do the conversion it supports.

Drivers set the flags
V4L2_FMT_FLAG_CSC_COLORSPACE,
V4L2_FMT_FLAG_CSC_YCBCR_ENC,
V4L2_FMT_FLAG_CSC_HSV_ENC,
V4L2_FMT_FLAG_CSC_QUANTIZATION,
V4L2_FMT_FLAG_CSC_XFER_FUNC,
in the flags field of the struct v4l2_fmtdesc during enumeration to
indicate that they support colorspace conversion for the respective field.

Drivers do not have to actually look at the flags. If the flags are not
set, then the fields 'colorspace', 'ycbcr_enc/hsv_enc', 'quantization'
and 'xfer_func' are set to the default values by the core, i.e. just
pass on the received format without conversion.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
---
 .../media/v4l/pixfmt-v4l2-mplane.rst          | 16 ++---
 .../userspace-api/media/v4l/pixfmt-v4l2.rst   | 64 +++++++++++++++++--
 .../media/v4l/vidioc-enum-fmt.rst             | 35 ++++++++++
 .../media/videodev2.h.rst.exceptions          |  5 ++
 include/uapi/linux/videodev2.h                |  6 ++
 5 files changed, 109 insertions(+), 17 deletions(-)

Comments

Hans Verkuil July 21, 2020, 1:47 p.m. UTC | #1
On 03/07/2020 19:10, Dafna Hirschfeld wrote:
> For video capture it is the driver that reports the colorspace,
> Y'CbCr/HSV encoding, quantization range and transfer function

In a lot of places in this series the colorimetry parameters are
ordered as colorspace, Y'CbCr/HSV encoding, quantization range and
transfer function, but 'transfer function' should come after
'colorspace'.

I.e. the linear RGB values using a specific colorspace are passed
through the transfer function (aka gamma), pixel encoding and finally
the quantization step. So this order should be kept in both code
and documentation wherever possible.

> used by the video, and there is no way to request something
> different, even though many HDTV receivers have some sort of
> colorspace conversion capabilities.
> 
> For output video this feature already exists since the application
> specifies this information for the video format it will send out, and
> the transmitter will enable any available CSC if a format conversion has
> to be performed in order to match the capabilities of the sink.
> 
> For video capture we propose adding new v4l2_pix_format flag:
> V4L2_PIX_FMT_FLAG_SET_CSC. The flag is set by the application,
> the driver will interpret the colorspace, ycbcr_enc/hsv_enc, quantization
> and xfer_func fields as the requested colorspace information and will

So reorder above,

> attempt to do the conversion it supports.
> 
> Drivers set the flags
> V4L2_FMT_FLAG_CSC_COLORSPACE,
> V4L2_FMT_FLAG_CSC_YCBCR_ENC,
> V4L2_FMT_FLAG_CSC_HSV_ENC,
> V4L2_FMT_FLAG_CSC_QUANTIZATION,
> V4L2_FMT_FLAG_CSC_XFER_FUNC,

and here (and combine the two ENCs to:

V4L2_FMT_FLAG_CSC_YCBCR_ENC/V4L2_FMT_FLAG_CSC_HSV_ENC,

> in the flags field of the struct v4l2_fmtdesc during enumeration to
> indicate that they support colorspace conversion for the respective field.
> 
> Drivers do not have to actually look at the flags. If the flags are not
> set, then the fields 'colorspace', 'ycbcr_enc/hsv_enc', 'quantization'
> and 'xfer_func' are set to the default values by the core, i.e. just

Reorder.

> pass on the received format without conversion.
> 
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
> ---
>  .../media/v4l/pixfmt-v4l2-mplane.rst          | 16 ++---
>  .../userspace-api/media/v4l/pixfmt-v4l2.rst   | 64 +++++++++++++++++--
>  .../media/v4l/vidioc-enum-fmt.rst             | 35 ++++++++++
>  .../media/videodev2.h.rst.exceptions          |  5 ++
>  include/uapi/linux/videodev2.h                |  6 ++
>  5 files changed, 109 insertions(+), 17 deletions(-)
> 
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst b/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
> index 444b4082684c..66f3365d7b72 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
> @@ -105,29 +105,21 @@ describing all planes of that format.
>      * - __u8
>        - ``ycbcr_enc``
>        - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
> -        This information supplements the ``colorspace`` and must be set by
> -	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	See struct :c:type:`v4l2_pix_format`.
>      * - __u8
>        - ``hsv_enc``
>        - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
> -        This information supplements the ``colorspace`` and must be set by
> -	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	See struct :c:type:`v4l2_pix_format`.
>      * - }
>        -
>      * - __u8
>        - ``quantization``
>        - Quantization range, from enum :c:type:`v4l2_quantization`.
> -        This information supplements the ``colorspace`` and must be set by
> -	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	See struct :c:type:`v4l2_pix_format`.
>      * - __u8
>        - ``xfer_func``
>        - Transfer function, from enum :c:type:`v4l2_xfer_func`.
> -        This information supplements the ``colorspace`` and must be set by
> -	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	See struct :c:type:`v4l2_pix_format`.
>      * - __u8
>        - ``reserved[7]``
>        - Reserved for future extensions. Should be zeroed by drivers and
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst b/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
> index 56a2952de873..d9f8f7eb7098 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
> @@ -116,7 +116,14 @@ Single-planar format structure
>        - Image colorspace, from enum :c:type:`v4l2_colorspace`.
>          This information supplements the ``pixelformat`` and must be set
>  	by the driver for capture streams and by the application for
> -	output streams, see :ref:`colorspaces`.
> +	output streams, see :ref:`colorspaces`. If the application sets the
> +	flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
> +	this field for a capture stream to request a specific colorspace
> +	for the captured image data. If the driver cannot handle requested
> +	conversion, it will return another supported colorspace.
> +	The driver indicates that colorspace conversion is supported by setting
> +	the flag V4L2_FMT_FLAG_CSC_COLORSPACE in the corresponding struct
> +	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
>      * - __u32
>        - ``priv``
>        - This field indicates whether the remaining fields of the
> @@ -153,13 +160,29 @@ Single-planar format structure
>        - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
>          This information supplements the ``colorspace`` and must be set by
>  	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	streams, see :ref:`colorspaces`. If the application sets the
> +	flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
> +	this field for a capture stream to request a specific Y'CbCr encoding
> +	for the captured image data. If the driver cannot handle requested
> +	conversion, it will return another supported encoding.
> +	This field is ignored for HSV pixelformats. The driver indicates that
> +	ycbcr_enc conversion is supported by setting the flag
> +	V4L2_FMT_FLAG_CSC_YCBCR_ENC in the corresponding struct
> +	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
>      * - __u32
>        - ``hsv_enc``
>        - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
>          This information supplements the ``colorspace`` and must be set by
>  	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	streams, see :ref:`colorspaces`. If the application sets the flag
> +	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set this
> +	field for a capture stream to request a specific HSV encoding for the
> +	captured image data. If the driver cannot handle requested
> +	conversion, it will return another supported encoding.
> +	This field is ignored for non-HSV pixelformats. The driver indicates
> +	that hsv_enc conversion is supported by setting the flag
> +	V4L2_FMT_FLAG_CSC_HSV_ENC in the corresponding struct
> +	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
>      * - }
>        -
>      * - __u32
> @@ -167,13 +190,27 @@ Single-planar format structure
>        - Quantization range, from enum :c:type:`v4l2_quantization`.
>          This information supplements the ``colorspace`` and must be set by
>  	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	streams, see :ref:`colorspaces`. If the application sets the flag
> +	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
> +	this field for a capture stream to request a specific quantization
> +	range for the captured image data. If the driver cannot handle requested
> +	conversion, it will return another supported encoding.
> +	The driver indicates that quantization conversion is supported by setting
> +	the flag V4L2_FMT_FLAG_CSC_QUANTIZATION in the corresponding struct
> +	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
>      * - __u32
>        - ``xfer_func``
>        - Transfer function, from enum :c:type:`v4l2_xfer_func`.
>          This information supplements the ``colorspace`` and must be set by
>  	the driver for capture streams and by the application for output
> -	streams, see :ref:`colorspaces`.
> +	streams, see :ref:`colorspaces`. If the application sets the flag
> +	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
> +	this field for a capture stream to request a specific Transfer function
> +	for the captured image data. If the driver cannot handle requested
> +	conversion, it will return another supported Transfer function.
> +	The driver indicates that xfer_func conversion is supported by setting
> +	the flag V4L2_FMT_FLAG_CSC_XFER_FUNC in the corresponding struct
> +	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
>  
>  .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
>  
> @@ -191,3 +228,20 @@ Single-planar format structure
>  	by RGBA values (128, 192, 255, 128), the same pixel described with
>  	premultiplied colors would be described by RGBA values (64, 96,
>  	128, 128)
> +    * .. _`v4l2-pix-fmt-flag-set-csc`:
> +
> +      - ``V4L2_PIX_FMT_FLAG_SET_CSC``
> +      - 0x00000002
> +      - Set by the application. It is only used for capture and is
> +        ignored for output streams. If set, then request the device to do
> +	colorspace conversion from the received colorspace to the requested
> +	colorspace values. If colorimetry field (``colorspace``, ``ycbcr_enc``,

If -> If the

> +	``hsv_enc``, ``quantization`` or ``xfer_func``) is set to 0, then that

reorder ``xfer_func``.

> +	colorimetry setting will remain unchanged from what was received. So to
> +	change the quantization only the ``quantization`` field shall be set to
> +	non-zero values (``V4L2_QUANTIZATION_FULL_RANGE`` or
> +	``V4L2_QUANTIZATION_LIM_RANGE``) and all other colorimetry fields shall
> +	be set to 0.
> +
> +	To check which conversions are supported by the hardware for the current
> +	pixel format, see :ref:`fmtdesc-flags`.
> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> index 05835e04c20b..98595dd48557 100644
> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> @@ -198,6 +198,41 @@ the ``mbus_code`` field is handled differently:
>  	This flag can only be used in combination with the
>  	``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to
>          compressed formats only. This flag is valid for stateful encoders only.
> +    * - ``V4L2_FMT_FLAG_CSC_COLORSPACE``
> +      - 0x0020
> +      - The driver allows the application to try to change the default
> +	colorspace. This flag is relevant only for capture devices.
> +	The application can ask to configure the colorspace of the capture device
> +	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
> +	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
> +    * - ``V4L2_FMT_FLAG_CSC_YCBCR_ENC``
> +      - 0x0040
> +      - The driver allows the application to try to change the default
> +	Y'CbCr encoding. This flag is relevant only for capture devices.
> +	The application can ask to configure the ycbcr_enc of the capture device
> +	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
> +	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
> +    * - ``V4L2_FMT_FLAG_CSC_HSV_ENC``
> +      - 0x0040
> +      - The driver allows the application to try to change the default
> +	HSV encoding. This flag is relevant only for capture devices.
> +	The application can ask to configure the hsv_enc of the capture device
> +	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
> +	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
> +    * - ``V4L2_FMT_FLAG_CSC_QUANTIZATION``
> +      - 0x0080
> +      - The driver allows the application to try to change the default
> +	quantization. This flag is relevant only for capture devices.
> +	The application can ask to configure the quantization of the capture
> +	device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
> +	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
> +    * - ``V4L2_FMT_FLAG_CSC_XFER_FUNC``
> +      - 0x0100

Reorder, the flag values also change.

> +      - The driver allows the application to try to change the default
> +	quantization. This flag is relevant only for capture devices.
> +	The application can ask to configure the quantization of the capture
> +	device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
> +	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
>  
>  
>  Return Value
> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> index 659799cc1eca..faa19e7d241b 100644
> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> @@ -188,6 +188,11 @@ replace define V4L2_FMT_FLAG_EMULATED fmtdesc-flags
>  replace define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM fmtdesc-flags
>  replace define V4L2_FMT_FLAG_DYN_RESOLUTION fmtdesc-flags
>  replace define V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL fmtdesc-flags
> +replace define V4L2_FMT_FLAG_CSC_COLORSPACE fmtdesc-flags
> +replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
> +replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
> +replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
> +replace define V4L2_FMT_FLAG_CSC_XFER_FUNC fmtdesc-flags

Reorder

>  
>  # V4L2 timecode types
>  replace define V4L2_TC_TYPE_24FPS timecode-type
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 303805438814..76610509d670 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -776,6 +776,7 @@ struct v4l2_pix_format {
>  
>  /* Flags */
>  #define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA	0x00000001
> +#define V4L2_PIX_FMT_FLAG_SET_CSC	0x00000002
>  
>  /*
>   *	F O R M A T   E N U M E R A T I O N
> @@ -795,6 +796,11 @@ struct v4l2_fmtdesc {
>  #define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM	0x0004
>  #define V4L2_FMT_FLAG_DYN_RESOLUTION		0x0008
>  #define V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL	0x0010
> +#define V4L2_FMT_FLAG_CSC_COLORSPACE		0x0020
> +#define V4L2_FMT_FLAG_CSC_YCBCR_ENC		0x0040
> +#define V4L2_FMT_FLAG_CSC_HSV_ENC		V4L2_FMT_FLAG_CSC_YCBCR_ENC
> +#define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0080
> +#define V4L2_FMT_FLAG_CSC_XFER_FUNC		0x0100

Reorder and renumber the values accordingly.

>  
>  	/* Frame Size and frame rate enumeration */
>  /*
> 

Regards,

	Hans

Patch
diff mbox series

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst b/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
index 444b4082684c..66f3365d7b72 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-v4l2-mplane.rst
@@ -105,29 +105,21 @@  describing all planes of that format.
     * - __u8
       - ``ycbcr_enc``
       - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
-        This information supplements the ``colorspace`` and must be set by
-	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	See struct :c:type:`v4l2_pix_format`.
     * - __u8
       - ``hsv_enc``
       - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
-        This information supplements the ``colorspace`` and must be set by
-	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	See struct :c:type:`v4l2_pix_format`.
     * - }
       -
     * - __u8
       - ``quantization``
       - Quantization range, from enum :c:type:`v4l2_quantization`.
-        This information supplements the ``colorspace`` and must be set by
-	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	See struct :c:type:`v4l2_pix_format`.
     * - __u8
       - ``xfer_func``
       - Transfer function, from enum :c:type:`v4l2_xfer_func`.
-        This information supplements the ``colorspace`` and must be set by
-	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	See struct :c:type:`v4l2_pix_format`.
     * - __u8
       - ``reserved[7]``
       - Reserved for future extensions. Should be zeroed by drivers and
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst b/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
index 56a2952de873..d9f8f7eb7098 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-v4l2.rst
@@ -116,7 +116,14 @@  Single-planar format structure
       - Image colorspace, from enum :c:type:`v4l2_colorspace`.
         This information supplements the ``pixelformat`` and must be set
 	by the driver for capture streams and by the application for
-	output streams, see :ref:`colorspaces`.
+	output streams, see :ref:`colorspaces`. If the application sets the
+	flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+	this field for a capture stream to request a specific colorspace
+	for the captured image data. If the driver cannot handle requested
+	conversion, it will return another supported colorspace.
+	The driver indicates that colorspace conversion is supported by setting
+	the flag V4L2_FMT_FLAG_CSC_COLORSPACE in the corresponding struct
+	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
     * - __u32
       - ``priv``
       - This field indicates whether the remaining fields of the
@@ -153,13 +160,29 @@  Single-planar format structure
       - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
         This information supplements the ``colorspace`` and must be set by
 	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	streams, see :ref:`colorspaces`. If the application sets the
+	flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+	this field for a capture stream to request a specific Y'CbCr encoding
+	for the captured image data. If the driver cannot handle requested
+	conversion, it will return another supported encoding.
+	This field is ignored for HSV pixelformats. The driver indicates that
+	ycbcr_enc conversion is supported by setting the flag
+	V4L2_FMT_FLAG_CSC_YCBCR_ENC in the corresponding struct
+	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
     * - __u32
       - ``hsv_enc``
       - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
         This information supplements the ``colorspace`` and must be set by
 	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	streams, see :ref:`colorspaces`. If the application sets the flag
+	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set this
+	field for a capture stream to request a specific HSV encoding for the
+	captured image data. If the driver cannot handle requested
+	conversion, it will return another supported encoding.
+	This field is ignored for non-HSV pixelformats. The driver indicates
+	that hsv_enc conversion is supported by setting the flag
+	V4L2_FMT_FLAG_CSC_HSV_ENC in the corresponding struct
+	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
     * - }
       -
     * - __u32
@@ -167,13 +190,27 @@  Single-planar format structure
       - Quantization range, from enum :c:type:`v4l2_quantization`.
         This information supplements the ``colorspace`` and must be set by
 	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	streams, see :ref:`colorspaces`. If the application sets the flag
+	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+	this field for a capture stream to request a specific quantization
+	range for the captured image data. If the driver cannot handle requested
+	conversion, it will return another supported encoding.
+	The driver indicates that quantization conversion is supported by setting
+	the flag V4L2_FMT_FLAG_CSC_QUANTIZATION in the corresponding struct
+	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
     * - __u32
       - ``xfer_func``
       - Transfer function, from enum :c:type:`v4l2_xfer_func`.
         This information supplements the ``colorspace`` and must be set by
 	the driver for capture streams and by the application for output
-	streams, see :ref:`colorspaces`.
+	streams, see :ref:`colorspaces`. If the application sets the flag
+	``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+	this field for a capture stream to request a specific Transfer function
+	for the captured image data. If the driver cannot handle requested
+	conversion, it will return another supported Transfer function.
+	The driver indicates that xfer_func conversion is supported by setting
+	the flag V4L2_FMT_FLAG_CSC_XFER_FUNC in the corresponding struct
+	:c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
 
 .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
 
@@ -191,3 +228,20 @@  Single-planar format structure
 	by RGBA values (128, 192, 255, 128), the same pixel described with
 	premultiplied colors would be described by RGBA values (64, 96,
 	128, 128)
+    * .. _`v4l2-pix-fmt-flag-set-csc`:
+
+      - ``V4L2_PIX_FMT_FLAG_SET_CSC``
+      - 0x00000002
+      - Set by the application. It is only used for capture and is
+        ignored for output streams. If set, then request the device to do
+	colorspace conversion from the received colorspace to the requested
+	colorspace values. If colorimetry field (``colorspace``, ``ycbcr_enc``,
+	``hsv_enc``, ``quantization`` or ``xfer_func``) is set to 0, then that
+	colorimetry setting will remain unchanged from what was received. So to
+	change the quantization only the ``quantization`` field shall be set to
+	non-zero values (``V4L2_QUANTIZATION_FULL_RANGE`` or
+	``V4L2_QUANTIZATION_LIM_RANGE``) and all other colorimetry fields shall
+	be set to 0.
+
+	To check which conversions are supported by the hardware for the current
+	pixel format, see :ref:`fmtdesc-flags`.
diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
index 05835e04c20b..98595dd48557 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
@@ -198,6 +198,41 @@  the ``mbus_code`` field is handled differently:
 	This flag can only be used in combination with the
 	``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to
         compressed formats only. This flag is valid for stateful encoders only.
+    * - ``V4L2_FMT_FLAG_CSC_COLORSPACE``
+      - 0x0020
+      - The driver allows the application to try to change the default
+	colorspace. This flag is relevant only for capture devices.
+	The application can ask to configure the colorspace of the capture device
+	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+    * - ``V4L2_FMT_FLAG_CSC_YCBCR_ENC``
+      - 0x0040
+      - The driver allows the application to try to change the default
+	Y'CbCr encoding. This flag is relevant only for capture devices.
+	The application can ask to configure the ycbcr_enc of the capture device
+	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+    * - ``V4L2_FMT_FLAG_CSC_HSV_ENC``
+      - 0x0040
+      - The driver allows the application to try to change the default
+	HSV encoding. This flag is relevant only for capture devices.
+	The application can ask to configure the hsv_enc of the capture device
+	when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+    * - ``V4L2_FMT_FLAG_CSC_QUANTIZATION``
+      - 0x0080
+      - The driver allows the application to try to change the default
+	quantization. This flag is relevant only for capture devices.
+	The application can ask to configure the quantization of the capture
+	device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+    * - ``V4L2_FMT_FLAG_CSC_XFER_FUNC``
+      - 0x0100
+      - The driver allows the application to try to change the default
+	quantization. This flag is relevant only for capture devices.
+	The application can ask to configure the quantization of the capture
+	device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+	:ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
 
 
 Return Value
diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
index 659799cc1eca..faa19e7d241b 100644
--- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
+++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
@@ -188,6 +188,11 @@  replace define V4L2_FMT_FLAG_EMULATED fmtdesc-flags
 replace define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM fmtdesc-flags
 replace define V4L2_FMT_FLAG_DYN_RESOLUTION fmtdesc-flags
 replace define V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL fmtdesc-flags
+replace define V4L2_FMT_FLAG_CSC_COLORSPACE fmtdesc-flags
+replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
+replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
+replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
+replace define V4L2_FMT_FLAG_CSC_XFER_FUNC fmtdesc-flags
 
 # V4L2 timecode types
 replace define V4L2_TC_TYPE_24FPS timecode-type
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 303805438814..76610509d670 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -776,6 +776,7 @@  struct v4l2_pix_format {
 
 /* Flags */
 #define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA	0x00000001
+#define V4L2_PIX_FMT_FLAG_SET_CSC	0x00000002
 
 /*
  *	F O R M A T   E N U M E R A T I O N
@@ -795,6 +796,11 @@  struct v4l2_fmtdesc {
 #define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM	0x0004
 #define V4L2_FMT_FLAG_DYN_RESOLUTION		0x0008
 #define V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL	0x0010
+#define V4L2_FMT_FLAG_CSC_COLORSPACE		0x0020
+#define V4L2_FMT_FLAG_CSC_YCBCR_ENC		0x0040
+#define V4L2_FMT_FLAG_CSC_HSV_ENC		V4L2_FMT_FLAG_CSC_YCBCR_ENC
+#define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0080
+#define V4L2_FMT_FLAG_CSC_XFER_FUNC		0x0100
 
 	/* Frame Size and frame rate enumeration */
 /*