Resize with Bilinear Interpolation¶

Changes an image size using the linear interpolation method.

Description

This function changes the image size using the linear interpolation method. The image size may be either reduced or increased in each direction, depending on the destination image size. The linear interpolation algorithm must use source image intensities at the four pixels in the neighborhood of the point in the source image. The weighted values of these pixels must be used for the destination image. Algorithm parameters must be set through the resize_bilinear_spec class. The border pixels are processed in accordance with the border type. This function can operate with ROI (see Image Regions of Interest).

Headers

oneapi/ipl/transform/resize_bilinear.hpp

Syntax

template<typename ComputeT = float, formats Format, typename DataT, typename SrcAllocatorT, typename DstAllocatorT> sycl::event oneapi::ipl::resize_bilinear(sycl::queue &queue, image<Format, DataT, SrcAllocatorT> &src, image<Format, DataT, DstAllocatorT> &dst, const resize_bilinear_spec &spec = {}, const std::vector<sycl::event> &dependencies = {})¶

Resize with the Bilinear interpolation method.

Template Parameters

ComputeT – type to perform calculations
Format – source/destination image format
DataT – source/destination image data type
SrcAllocatorT – source image allocator
DstAllocatorT – destination image allocator

Parameters

queue – [in] SYCL queue
src – [in] source image
dst – [out] destination image
spec – [in] algorithmic specification
dependencies – [in] other events dependencies

Returns

SYCL event, that represents a status of an operation it associated with

Supported values for ComputeT:

float	double	half
v	v	x

Supported combinations for DataT/Formats:

DataT/Formats	plane	rgb/bgr	rgba/bgra	rgbp
std::uint8_t	v	v	v	x
std::int8_t	v	v	v	x
std::uint16_t	v	v	v	x
std::int16_t	v	v	v	x
std::uint32_t	v	v	v	x
std::int32_t	v	v	v	x
float	v	v	v	x
double	v	v	v	x

Supported values for subsampled Format (only for DataT = std::uint8_t):

nv12	i420
v	v

Parameters

border type support

Type of border. Possible values are:

repl - Border is replicated from the edge pixels.

class oneapi::ipl::resize_bilinear_spec : public oneapi::ipl::border_spec_base<>¶

Bilinear resize parameters.

Public Types

using native_pixel_t = sycl::vec<std::uint8_t, 1>¶: Type alias for pixel type.

Public Functions

crop_types get_crop() const noexcept¶

Returns the crop type.

Returns: crop type

border_types get_border() const noexcept¶

Returns the border type.

Returns: border type

auto get_border_val() const noexcept -> const native_pixel_t&¶

Returns the border value.

Returns: border value

auto get_border_val_ptr() const -> const std::uint8_t*¶

Returns the border value pointer.

Returns: border value pointer

Errors

compile-time format check	Indicates an error when image format is not supported.
compile-time data type check	Indicates an error when image data type is not supported.
compile-time compute data type check	Indicates an error when compute data type is not supported.
`invalid_argument` exception	Indicates an error when one of the pitch values is not divisible by size of component data type in bytes.
`unimplemented` exception	Indicates an error when border type is not supported.

The code example below demonstrates how to use the oneapi::ipl::resize_bilinear:

// Create queue
sycl::queue queue{};

// Source rgba image data (image_image)
image<formats::rgba, std::uint8_t> src_image{ src_data_pointer, src_size };
// Destination rgba image data (image_image)
image<formats::rgba, std::uint8_t> dst_image{ dst_size };

(void)resize_bilinear(queue, src_image, dst_image);

oneIPL Specification documentation

Resize with Bilinear Interpolation¶