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-rw-r--r--Documentation/userspace-api/media/v4l/colorspaces-defs.rst9
-rw-r--r--Documentation/userspace-api/media/v4l/colorspaces-details.rst5
-rw-r--r--include/uapi/linux/videodev2.h17
3 files changed, 14 insertions, 17 deletions
diff --git a/Documentation/userspace-api/media/v4l/colorspaces-defs.rst b/Documentation/userspace-api/media/v4l/colorspaces-defs.rst
index 01404e1f609a..4089f426258d 100644
--- a/Documentation/userspace-api/media/v4l/colorspaces-defs.rst
+++ b/Documentation/userspace-api/media/v4l/colorspaces-defs.rst
@@ -36,8 +36,7 @@ whole range, 0-255, dividing the angular value by 1.41. The enum
:c:type:`v4l2_hsv_encoding` specifies which encoding is used.
.. note:: The default R'G'B' quantization is full range for all
- colorspaces except for BT.2020 which uses limited range R'G'B'
- quantization.
+ colorspaces. HSV formats are always full range.
.. tabularcolumns:: |p{6.7cm}|p{10.8cm}|
@@ -169,8 +168,8 @@ whole range, 0-255, dividing the angular value by 1.41. The enum
- Details
* - ``V4L2_QUANTIZATION_DEFAULT``
- Use the default quantization encoding as defined by the
- colorspace. This is always full range for R'G'B' (except for the
- BT.2020 colorspace) and HSV. It is usually limited range for Y'CbCr.
+ colorspace. This is always full range for R'G'B' and HSV.
+ It is usually limited range for Y'CbCr.
* - ``V4L2_QUANTIZATION_FULL_RANGE``
- Use the full range quantization encoding. I.e. the range [0…1] is
mapped to [0…255] (with possible clipping to [1…254] to avoid the
@@ -180,4 +179,4 @@ whole range, 0-255, dividing the angular value by 1.41. The enum
* - ``V4L2_QUANTIZATION_LIM_RANGE``
- Use the limited range quantization encoding. I.e. the range [0…1]
is mapped to [16…235]. Cb and Cr are mapped from [-0.5…0.5] to
- [16…240].
+ [16…240]. Limited Range cannot be used with HSV.
diff --git a/Documentation/userspace-api/media/v4l/colorspaces-details.rst b/Documentation/userspace-api/media/v4l/colorspaces-details.rst
index 300c5d2e7d0f..cf1b825ec34a 100644
--- a/Documentation/userspace-api/media/v4l/colorspaces-details.rst
+++ b/Documentation/userspace-api/media/v4l/colorspaces-details.rst
@@ -377,9 +377,8 @@ Colorspace BT.2020 (V4L2_COLORSPACE_BT2020)
The :ref:`itu2020` standard defines the colorspace used by Ultra-high
definition television (UHDTV). The default transfer function is
``V4L2_XFER_FUNC_709``. The default Y'CbCr encoding is
-``V4L2_YCBCR_ENC_BT2020``. The default R'G'B' quantization is limited
-range (!), and so is the default Y'CbCr quantization. The chromaticities
-of the primary colors and the white reference are:
+``V4L2_YCBCR_ENC_BT2020``. The default Y'CbCr quantization is limited range.
+The chromaticities of the primary colors and the white reference are:
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 235db7754606..f717826d5d7c 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -373,9 +373,9 @@ enum v4l2_hsv_encoding {
enum v4l2_quantization {
/*
- * The default for R'G'B' quantization is always full range, except
- * for the BT2020 colorspace. For Y'CbCr the quantization is always
- * limited range, except for COLORSPACE_JPEG: this is full range.
+ * The default for R'G'B' quantization is always full range.
+ * For Y'CbCr the quantization is always limited range, except
+ * for COLORSPACE_JPEG: this is full range.
*/
V4L2_QUANTIZATION_DEFAULT = 0,
V4L2_QUANTIZATION_FULL_RANGE = 1,
@@ -384,14 +384,13 @@ enum v4l2_quantization {
/*
* Determine how QUANTIZATION_DEFAULT should map to a proper quantization.
- * This depends on whether the image is RGB or not, the colorspace and the
- * Y'CbCr encoding.
+ * This depends on whether the image is RGB or not, the colorspace.
+ * The Y'CbCr encoding is not used anymore, but is still there for backwards
+ * compatibility.
*/
#define V4L2_MAP_QUANTIZATION_DEFAULT(is_rgb_or_hsv, colsp, ycbcr_enc) \
- (((is_rgb_or_hsv) && (colsp) == V4L2_COLORSPACE_BT2020) ? \
- V4L2_QUANTIZATION_LIM_RANGE : \
- (((is_rgb_or_hsv) || (colsp) == V4L2_COLORSPACE_JPEG) ? \
- V4L2_QUANTIZATION_FULL_RANGE : V4L2_QUANTIZATION_LIM_RANGE))
+ (((is_rgb_or_hsv) || (colsp) == V4L2_COLORSPACE_JPEG) ? \
+ V4L2_QUANTIZATION_FULL_RANGE : V4L2_QUANTIZATION_LIM_RANGE)
/*
* Deprecated names for opRGB colorspace (IEC 61966-2-5)