diff --git a/include/libcamera/internal/v4l2_device.h b/include/libcamera/internal/v4l2_device.h index 8886b750..a52a5f2c 100644 --- a/include/libcamera/internal/v4l2_device.h +++ b/include/libcamera/internal/v4l2_device.h @@ -9,6 +9,7 @@ #include #include +#include #include #include @@ -18,6 +19,7 @@ #include #include +#include #include namespace libcamera { @@ -56,6 +58,12 @@ protected: int fd() const { return fd_.get(); } + template + static std::optional toColorSpace(const T &v4l2Format); + + template + static int fromColorSpace(const std::optional &colorSpace, T &v4l2Format); + private: static ControlType v4l2CtrlType(uint32_t ctrlType); static std::unique_ptr v4l2ControlId(const v4l2_query_ext_ctrl &ctrl); diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp index 39f36009..3e8a180f 100644 --- a/src/libcamera/v4l2_device.cpp +++ b/src/libcamera/v4l2_device.cpp @@ -10,11 +10,15 @@ #include #include #include +#include #include #include #include #include #include +#include + +#include #include #include @@ -728,4 +732,194 @@ void V4L2Device::eventAvailable() frameStart.emit(event.u.frame_sync.frame_sequence); } +static const std::map v4l2ToColorSpace = { + { V4L2_COLORSPACE_RAW, ColorSpace::Raw }, + { V4L2_COLORSPACE_JPEG, ColorSpace::Jpeg }, + { V4L2_COLORSPACE_SRGB, ColorSpace::Srgb }, + { V4L2_COLORSPACE_SMPTE170M, ColorSpace::Smpte170m }, + { V4L2_COLORSPACE_REC709, ColorSpace::Rec709 }, + { V4L2_COLORSPACE_BT2020, ColorSpace::Rec2020 }, +}; + +static const std::map v4l2ToTransferFunction = { + { V4L2_XFER_FUNC_NONE, ColorSpace::TransferFunction::Linear }, + { V4L2_XFER_FUNC_SRGB, ColorSpace::TransferFunction::Srgb }, + { V4L2_XFER_FUNC_709, ColorSpace::TransferFunction::Rec709 }, +}; + +static const std::map v4l2ToYcbcrEncoding = { + { V4L2_YCBCR_ENC_601, ColorSpace::YcbcrEncoding::Rec601 }, + { V4L2_YCBCR_ENC_709, ColorSpace::YcbcrEncoding::Rec709 }, + { V4L2_YCBCR_ENC_BT2020, ColorSpace::YcbcrEncoding::Rec2020 }, +}; + +static const std::map v4l2ToRange = { + { V4L2_QUANTIZATION_FULL_RANGE, ColorSpace::Range::Full }, + { V4L2_QUANTIZATION_LIM_RANGE, ColorSpace::Range::Limited }, +}; + +static const std::vector> colorSpaceToV4l2 = { + { ColorSpace::Raw, V4L2_COLORSPACE_RAW }, + { ColorSpace::Jpeg, V4L2_COLORSPACE_JPEG }, + { ColorSpace::Srgb, V4L2_COLORSPACE_SRGB }, + { ColorSpace::Smpte170m, V4L2_COLORSPACE_SMPTE170M }, + { ColorSpace::Rec709, V4L2_COLORSPACE_REC709 }, + { ColorSpace::Rec2020, V4L2_COLORSPACE_BT2020 }, +}; + +static const std::map primariesToV4l2 = { + { ColorSpace::Primaries::Raw, V4L2_COLORSPACE_RAW }, + { ColorSpace::Primaries::Smpte170m, V4L2_COLORSPACE_SMPTE170M }, + { ColorSpace::Primaries::Rec709, V4L2_COLORSPACE_REC709 }, + { ColorSpace::Primaries::Rec2020, V4L2_COLORSPACE_BT2020 }, +}; + +static const std::map transferFunctionToV4l2 = { + { ColorSpace::TransferFunction::Linear, V4L2_XFER_FUNC_NONE }, + { ColorSpace::TransferFunction::Srgb, V4L2_XFER_FUNC_SRGB }, + { ColorSpace::TransferFunction::Rec709, V4L2_XFER_FUNC_709 }, +}; + +static const std::map ycbcrEncodingToV4l2 = { + { ColorSpace::YcbcrEncoding::Rec601, V4L2_YCBCR_ENC_601 }, + { ColorSpace::YcbcrEncoding::Rec709, V4L2_YCBCR_ENC_709 }, + { ColorSpace::YcbcrEncoding::Rec2020, V4L2_YCBCR_ENC_BT2020 }, +}; + +static const std::map rangeToV4l2 = { + { ColorSpace::Range::Full, V4L2_QUANTIZATION_FULL_RANGE }, + { ColorSpace::Range::Limited, V4L2_QUANTIZATION_LIM_RANGE }, +}; + +/** + * \brief Convert the color space fields in a V4L2 format to a ColorSpace + * \param[in] v4l2Format A V4L2 format containing color space information + * + * The colorspace, ycbcr_enc, xfer_func and quantization fields within a + * V4L2 format structure are converted to a corresponding ColorSpace. + * + * If any V4L2 fields are not recognised then we return an "unset" + * color space. + * + * \return The ColorSpace corresponding to the input V4L2 format + * \retval std::nullopt One or more V4L2 color space fields were not recognised + */ +template +std::optional V4L2Device::toColorSpace(const T &v4l2Format) +{ + auto itColor = v4l2ToColorSpace.find(v4l2Format.colorspace); + if (itColor == v4l2ToColorSpace.end()) + return std::nullopt; + + /* This sets all the color space fields to the correct "default" values. */ + ColorSpace colorSpace = itColor->second; + + if (v4l2Format.ycbcr_enc != V4L2_YCBCR_ENC_DEFAULT) { + auto itYcbcrEncoding = v4l2ToYcbcrEncoding.find(v4l2Format.ycbcr_enc); + if (itYcbcrEncoding == v4l2ToYcbcrEncoding.end()) + return std::nullopt; + + colorSpace.ycbcrEncoding = itYcbcrEncoding->second; + } + + if (v4l2Format.xfer_func != V4L2_XFER_FUNC_DEFAULT) { + auto itTransfer = v4l2ToTransferFunction.find(v4l2Format.xfer_func); + if (itTransfer == v4l2ToTransferFunction.end()) + return std::nullopt; + + colorSpace.transferFunction = itTransfer->second; + } + + if (v4l2Format.quantization != V4L2_QUANTIZATION_DEFAULT) { + auto itRange = v4l2ToRange.find(v4l2Format.quantization); + if (itRange == v4l2ToRange.end()) + return std::nullopt; + + colorSpace.range = itRange->second; + } + + return colorSpace; +} + +template std::optional V4L2Device::toColorSpace(const struct v4l2_pix_format &); +template std::optional V4L2Device::toColorSpace(const struct v4l2_pix_format_mplane &); +template std::optional V4L2Device::toColorSpace(const struct v4l2_mbus_framefmt &); + +/** + * \brief Fill in the color space fields of a V4L2 format from a ColorSpace + * \param[in] colorSpace The ColorSpace to be converted + * \param[out] v4l2Format A V4L2 format containing color space information + * + * The colorspace, ycbcr_enc, xfer_func and quantization fields within a + * V4L2 format structure are filled in from a corresponding ColorSpace. + * + * An error is returned if any of the V4L2 fields do not support the + * value given in the ColorSpace. Such fields are set to the V4L2 + * "default" values, but all other fields are still filled in where + * possible. + * + * If the color space is completely unset, "default" V4L2 values are used + * everywhere, so a driver would then choose its preferred color space. + * + * \return 0 on success or a negative error code otherwise + * \retval -EINVAL The ColorSpace does not have a representation using V4L2 enums + */ +template +int V4L2Device::fromColorSpace(const std::optional &colorSpace, T &v4l2Format) +{ + v4l2Format.colorspace = V4L2_COLORSPACE_DEFAULT; + v4l2Format.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT; + v4l2Format.xfer_func = V4L2_XFER_FUNC_DEFAULT; + v4l2Format.quantization = V4L2_QUANTIZATION_DEFAULT; + + if (!colorSpace) + return 0; + + auto itColor = std::find_if(colorSpaceToV4l2.begin(), colorSpaceToV4l2.end(), + [&colorSpace](const auto &item) { + return colorSpace == item.first; + }); + if (itColor != colorSpaceToV4l2.end()) { + v4l2Format.colorspace = itColor->second; + /* Leaving all the other fields as "default" should be fine. */ + return 0; + } + + /* + * If the colorSpace doesn't precisely match a standard color space, + * then we must choose a V4L2 colorspace with matching primaries. + */ + int ret = 0; + + auto itPrimaries = primariesToV4l2.find(colorSpace->primaries); + if (itPrimaries != primariesToV4l2.end()) + v4l2Format.colorspace = itPrimaries->second; + else + ret = -EINVAL; + + auto itYcbcrEncoding = ycbcrEncodingToV4l2.find(colorSpace->ycbcrEncoding); + if (itYcbcrEncoding != ycbcrEncodingToV4l2.end()) + v4l2Format.ycbcr_enc = itYcbcrEncoding->second; + else + ret = -EINVAL; + + auto itTransfer = transferFunctionToV4l2.find(colorSpace->transferFunction); + if (itTransfer != transferFunctionToV4l2.end()) + v4l2Format.xfer_func = itTransfer->second; + else + ret = -EINVAL; + + auto itRange = rangeToV4l2.find(colorSpace->range); + if (itRange != rangeToV4l2.end()) + v4l2Format.quantization = itRange->second; + else + ret = -EINVAL; + + return ret; +} + +template int V4L2Device::fromColorSpace(const std::optional &, struct v4l2_pix_format &); +template int V4L2Device::fromColorSpace(const std::optional &, struct v4l2_pix_format_mplane &); +template int V4L2Device::fromColorSpace(const std::optional &, struct v4l2_mbus_framefmt &); + } /* namespace libcamera */