cvw::ImageMutView

Mutable, non-owning view over image pixel data. More...

#include <image_view.hpp>

Public Types

	Name
using typename F::value_type	value_type Scalar element type derived from the pixel format.

Public Functions

	Name
	ImageMutView() =default Default-constructs a null view.
	ImageMutView(value_type * data, int width, int height, size_t stride) Constructs a mutable view from a pointer and dimensions.
int	width() const Returns the image width in pixels.
int	height() const Returns the image height in pixels.
constexprint	channels() const Returns the number of channels determined by the format.
size_t	stride() const Returns the row stride in elements.
bool	empty() const Checks whether the view references no data.
value_type *	data() Returns a mutable pointer to pixel data.
constvalue_type *	data() const Returns a const pointer to pixel data.
value_type &	at(int row, int col, int ch =0) Accesses a specific pixel channel by coordinates.
ImageView<F>	as_const_view() const Converts this mutable view to a read-only ImageView.

Detailed Description

template <is_pixel_format F>
class cvw::ImageMutView;

Mutable, non-owning view over image pixel data.

Template Parameters:

• F Pixel format tag satisfying is_pixel_format.

Since: 1.0.0

Note: Not thread-safe unless externally synchronized.

Provides read-write access to an external pixel buffer. Does not manage the underlying memory; the caller must ensure the buffer outlives the view.

cvw::Image<cvw::Gray> img(640, 480);
auto mv = img.mutable_view();
mv.at(0, 0) = 128;

Public Types Documentation

using value_type

using cvw::ImageMutView<F>::value_type =  typename F::value_type;

Scalar element type derived from the pixel format.

Public Functions Documentation

function ImageMutView

ImageMutView() =default

Default-constructs a null view.

Since: 1.0.0

function ImageMutView

inline ImageMutView(
    value_type * data,
    int width,
    int height,
    size_t stride
)

Constructs a mutable view from a pointer and dimensions.

Parameters:

• data Pointer to the first pixel element. Must be non-null if width * height > 0.
• width Image width in pixels.
• height Image height in pixels.
• stride Row stride in elements (not bytes).

Since: 1.0.0

function width

inline int width() const

Returns the image width in pixels.

Return: Width in pixels.

Since: 1.0.0

function height

inline int height() const

Returns the image height in pixels.

Return: Height in pixels.

Since: 1.0.0

function channels

inline constexprint channels() const

Returns the number of channels determined by the format.

Return: Channel count (compile-time constant).

Since: 1.0.0

function stride

inline size_t stride() const

Returns the row stride in elements.

Return: Stride in elements (not bytes).

Since: 1.0.0

function empty

inline bool empty() const

Checks whether the view references no data.

Return: True if the data pointer is null.

Since: 1.0.0

function data

inline value_type * data()

Returns a mutable pointer to pixel data.

Return: Mutable pointer to the first element.

Since: 1.0.0

function data

inline constvalue_type * data() const

Returns a const pointer to pixel data.

Return: Const pointer to the first element.

Since: 1.0.0

function at

inline value_type & at(
    int row,
    int col,
    int ch =0
)

Accesses a specific pixel channel by coordinates.

Parameters:

• row Row index. Unit: pixels. Valid range: 0, height).
• col Column index. Unit: pixels. Valid range: [0, width).
• ch Channel index. Default: 0.

Exceptions:

• None (no bounds checking).

Return: Mutable reference to the channel value.

Since: 1.0.0

Warning: Undefined behavior for out-of-range indices.

function as_const_view

inline ImageView<F> as_const_view() const

Converts this mutable view to a read-only [ImageView.

Return: An ImageView referencing the same pixel buffer.

Since: 1.0.0

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