diff --git a/Documentation/media/uapi/v4l/colorspaces-defs.rst b/Documentation/media/uapi/v4l/colorspaces-defs.rst index e122bbe3d799..aabb08130354 100644 --- a/Documentation/media/uapi/v4l/colorspaces-defs.rst +++ b/Documentation/media/uapi/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/media/uapi/v4l/colorspaces-details.rst b/Documentation/media/uapi/v4l/colorspaces-details.rst index 8b0ba3668101..fd0cf57691d8 100644 --- a/Documentation/media/uapi/v4l/colorspaces-details.rst +++ b/Documentation/media/uapi/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 530638dffd93..3210b3c82a4a 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -371,9 +371,9 @@ 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, @@ -382,14 +382,13 @@ 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)