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Diffstat (limited to 'Documentation/media/uapi/v4l/pixfmt-007.rst')
| -rw-r--r-- | Documentation/media/uapi/v4l/pixfmt-007.rst | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/Documentation/media/uapi/v4l/pixfmt-007.rst b/Documentation/media/uapi/v4l/pixfmt-007.rst index 5e39cda6147a..8c946b0c63a0 100644 --- a/Documentation/media/uapi/v4l/pixfmt-007.rst +++ b/Documentation/media/uapi/v4l/pixfmt-007.rst @@ -536,11 +536,13 @@ Colorspace DCI-P3 (V4L2_COLORSPACE_DCI_P3) The :ref:`smpte431` standard defines the colorspace used by cinema projectors that use the DCI-P3 colorspace. The default transfer function is ``V4L2_XFER_FUNC_DCI_P3``. The default Y'CbCr encoding is -``V4L2_YCBCR_ENC_709``. Note that this colorspace does not specify a -Y'CbCr encoding since it is not meant to be encoded to Y'CbCr. So this -default Y'CbCr encoding was picked because it is the HDTV encoding. The -default Y'CbCr quantization is limited range. The chromaticities of the -primary colors and the white reference are: +``V4L2_YCBCR_ENC_709``. + +.. note:: Note that this colorspace does not specify a + Y'CbCr encoding since it is not meant to be encoded to Y'CbCr. So this + default Y'CbCr encoding was picked because it is the HDTV encoding. The + default Y'CbCr quantization is limited range. The chromaticities of the + primary colors and the white reference are: @@ -752,10 +754,10 @@ reference are: - 0.316 -Note that this colorspace uses Illuminant C instead of D65 as the white -reference. To correctly convert an image in this colorspace to another -that uses D65 you need to apply a chromatic adaptation algorithm such as -the Bradford method. +.. note:: This colorspace uses Illuminant C instead of D65 as the white + reference. To correctly convert an image in this colorspace to another + that uses D65 you need to apply a chromatic adaptation algorithm such as + the Bradford method. The transfer function was never properly defined for NTSC 1953. The Rec. 709 transfer function is recommended in the literature: @@ -886,9 +888,9 @@ reference are identical to sRGB. The transfer function use is with full range quantization where Y' is scaled to [0…255] and Cb/Cr are scaled to [-128…128] and then clipped to [-128…127]. -Note that the JPEG standard does not actually store colorspace -information. So if something other than sRGB is used, then the driver -will have to set that information explicitly. Effectively -``V4L2_COLORSPACE_JPEG`` can be considered to be an abbreviation for -``V4L2_COLORSPACE_SRGB``, ``V4L2_YCBCR_ENC_601`` and -``V4L2_QUANTIZATION_FULL_RANGE``. +.. note:: The JPEG standard does not actually store colorspace + information. So if something other than sRGB is used, then the driver + will have to set that information explicitly. Effectively + ``V4L2_COLORSPACE_JPEG`` can be considered to be an abbreviation for + ``V4L2_COLORSPACE_SRGB``, ``V4L2_YCBCR_ENC_601`` and + ``V4L2_QUANTIZATION_FULL_RANGE``. |
