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# Changelog

This file documents significant changes between KleidiCV releases.

KleidiCV uses [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

This changelog aims to follow the guiding principles of
[Keep a Changelog](https://keepachangelog.com/en/1.1.0/).

## 0.3.0 - not yet released

### Added
- Remap implementation
  - 2-channel s16 and s16+u16 fixed-point coordinates and 1-channel u8 input, replicated borders.
  - 2-channel s16 + 5+5 bits' fractions fixed-point coordinates and 1-channel u8 input, replicated borders.
- WarpPerspective implementation
  - Nearest neighbour implementation for replicated borders and 1-channel u8 input.
- Implementation of cv::pyrDown in the OpenCV HAL.
- Implementation of cv::buildOpticalFlowPyramid in the OpenCV HAL.
- Sum implementation for 1-channel f32 input (not exposed to OpenCV).

### Changed
- Build options `KLEIDICV_ENABLE_SVE2` and `KLEIDICV_ENABLE_SME2` take effect directly.
  Previously the build scripts had additional checks that attempted to identify whether the compiler supported SVE2/SME2 - these checks have been removed.
- The default setting for `KLEIDICV_ENABLE_SVE2` is on for some popular compilers known to support SVE2, otherwise off.
- `KLEIDICV_ENABLE_SME2` defaults to off. This is because the ACLE SME specification has not yet been finalized.
- In the OpenCV HAL, cvtColor for gray-RGBA & BGRA-RGBA are multithreaded.
- Improved performance of 8-bit int to 32-bit float conversion.

## 0.2.0 - 2024-09-30

### Added
- Exponential function for float.
- Bitwise and.
- Gaussian Blur for 7x7 kernels.
- Gaussian Blur for 15x15 kernels.
- Separable Filter 2D for 5x5 kernels (not exposed to OpenCV).
- Enable specifying standard deviation for Gaussian blur.
- Scale function for float.
- Add, subtract, multiply & absdiff enabled in OpenCV HAL.
- MinMax enabled in OpenCV HAL, float version added.
- Resize 4x4 for float.
- Resize 8x8 for float.
- Resize 0.5x0.5 for uint8_t.
- Conversion from float to (u)int8_t and vice versa.
- KLEIDICV_LIMIT_SME2_TO_SELECTED_ALGORITHMS configuration option.
- Conversion from non-subsampled, interleaved YUV to RGB/BGR.
- InRange single channel, scalar bounds for uint8_t and float.

### Changed
- Filter context creation API specification.
- Gaussian Blur API specification.
- In the OpenCV HAL, the following operations are multithreaded:
  * cvtColor
  * convertTo
  * exp
  * minMaxIdx
  * GaussianBlur
  * Sobel
  * resize

### Removed
- Support for OpenCV 4.9.
- threshold from OpenCV HAL.

## 0.1.0 - 2024-05-21

Initial release.