cvw::detail

Internal validation helpers used by algorithm implementations. More...

Functions

	Name
template <is_pixel_format F&gt; auto	check_non_empty(constImage<F> & img) Validates that an Image is not empty.
template <is_pixel_format F&gt; auto	check_non_empty(constImageView<F> & view) Validates that an ImageView is not empty.
auto	require_odd(int k) Validates that a kernel size is a positive odd integer.
auto	require_positive_dim(int w, int h) Validates that width and height are both positive.
template <is_pixel_format F&gt; constexprint	imread_flag() Resolves the OpenCV imread flag for a given pixel format.
template <typename T &gt; constexprint	cv_depth() Maps a C++ scalar type to the corresponding OpenCV depth flag.
template <is_pixel_format F&gt; constexprint	cv_type() Computes the full OpenCV type flag for a pixel format.
template <typename Src ,typename Dst &gt; constevalint	cvt_color_code() Resolves the OpenCV color conversion code at compile time.
auto	make_pipeline_impl() Base case: returns an identity step wrapping the input.
template <typename First ,typename... Rest&gt; auto	make_pipeline_impl(First && first, Rest &&... rest) Recursive case: composes a step with the tail pipeline.

Detailed Description

Internal validation helpers used by algorithm implementations.

Internal helpers for make_pipeline.

Internal helpers for Image implementation.

Internal helpers for image loading.

Functions Documentation

function check_non_empty

template <is_pixel_format F>
inline auto check_non_empty(
    constImage<F> & img
)

Validates that an Image is not empty.

Parameters:

• img Image to validate.

Template Parameters:

• F Pixel format tag.

Return: Success if non-empty, otherwise AlgorithmError::EmptyInput.

Since: 1.0.0

function check_non_empty

template <is_pixel_format F>
inline auto check_non_empty(
    constImageView<F> & view
)

Validates that an ImageView is not empty.

Parameters:

• view View to validate.

Template Parameters:

• F Pixel format tag.

Return: Success if non-empty, otherwise AlgorithmError::EmptyInput.

Since: 1.0.0

function require_odd

inline auto require_odd(
    int k
)

Validates that a kernel size is a positive odd integer.

Parameters:

• k Kernel size parameter.

Return: Success if valid, otherwise AlgorithmError::InvalidParameter.

Since: 1.0.0

function require_positive_dim

inline auto require_positive_dim(
    int w,
    int h
)

Validates that width and height are both positive.

Parameters:

• w Width to validate. Unit: pixels.
• h Height to validate. Unit: pixels.

Return: Success if both positive, otherwise AlgorithmError::InvalidParameter.

Since: 1.0.0

function imread_flag

template <is_pixel_format F>
constexprint imread_flag()

Resolves the OpenCV imread flag for a given pixel format.

Template Parameters:

• F Target pixel format tag.

Return: OpenCV imread flag constant.

Since: 1.0.0

Selects the appropriate loading mode (grayscale, unchanged, color) based on the target format.

function cv_depth

template <typename T>
constexprint cv_depth()

Maps a C++ scalar type to the corresponding OpenCV depth flag.

Exceptions:

• Compile-time error for unsupported types.

Template Parameters:

• T Scalar type (uint8_t, uint16_t, float, double).

Return: OpenCV depth constant (CV_8U, CV_16U, CV_32F, CV_64F).

Since: 1.0.0

function cv_type

template <is_pixel_format F>
constexprint cv_type()

Computes the full OpenCV type flag for a pixel format.

Template Parameters:

• F Pixel format tag.

Return: OpenCV type constant (e.g., CV_8UC3).

Since: 1.0.0

Combines the depth and channel count into a CV_MAKETYPE value.

function cvt_color_code

template <typename Src ,
typename Dst >
constevalint cvt_color_code()

Resolves the OpenCV color conversion code at compile time.

Template Parameters:

• Src Source pixel format.
• Dst Destination pixel format.

Return: Color conversion code.

Since: 1.0.0

Returns -1 when no color conversion is needed (same family), -2 for unsupported conversions, or a valid cv::COLOR_* constant.

function make_pipeline_impl

inline auto make_pipeline_impl()

Base case: returns an identity step wrapping the input.

Return: A callable that wraps the input in a successful Expected.

Since: 1.0.0

function make_pipeline_impl

template <typename First ,
typename... Rest>
auto make_pipeline_impl(
    First && first,
    Rest &&... rest
)

Recursive case: composes a step with the tail pipeline.

Parameters:

• first First step callable.
• rest Remaining step callables.

Template Parameters:

• First Type of the first step.
• Rest Types of remaining steps.

Return: A callable that applies all steps sequentially with error propagation.

Since: 1.0.0

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Updated on 2026-05-17 at 13:22:38 +0000