OpenCV 4.9.0 released, Intel’s open source computer vision library

OpenCV is Intel's open source computer vision library, which implements many common algorithms in image processing and computer vision. The main updates of OpenCV 4.9.0 version are as follows:

• Core Module：

  • #23965  addedcv::broadcast
• DNN module patches：
  • Experimental transformers support
  • #24476  ONNX Attention layer support
  • #24037  ONNX Einsum layer support
  • #23987  OpenVINO backend for INT8 models
  • #24092 ONNX Gather Elements layer
  • #24378 ONNX InstanceNorm layer
  • #23897  #24694  #24509  New fastGEMM implementation and multiple layers on top of it
  • #23654  Winograd fp16 optimization on ARM
  • Testing and multiple fixes for Yolo series model support
  • New layer support and bug fixes in CUDA backend: GEMM, Gelu, Add
  • #24462  CANN backend: bug fix, support HardSwish, LayerNormalization and InstanceNormalization
  • #24552  LayerNormalization: Support OpenVINO, OpenCL and CUDA backends

• G-API module:

  • TBD

• Objdetect module:

  • #24364  Bug fix in QR code encoder version estimation 
  • #24479  Fixed contour filtering in ArUco
  • #24598  QR code detection example for Android
  • Multiple local bug fixes and documentation updates for Aruco makers, Charuco boards and QR codes.

• Video：

  • #24201 Google Summer of Code:  Added new object tracking API  for VitTrack  based on the visual converter  TrackerVit.

• Calibration module：

  • Multiple fixes and improvements to chess board calibration rig detector.
  • #23025  If the calibration system constraints are insufficient, calibrateCamera will throw an exception.
  • #24482  Fixed bug in USAC’s findEssentialMat
  • #24527  Fixed cv::cornerSubPixout-of-image access in
  • #23607  Fixed crash in ap3p
  • #24035  Fix stereoRectify image boundaries
  • #24211  Fixed “use after free” issue in Essential_solver.cpp

• Python bindings:

  • Added type stub generation for missing types and manually wrapped types.
  • #24026  Added read-only flag handling for Numpy arrays.
  • #24028  Fixed exception handling and binding within modules.
  • #23958  Improved error messages in Numpy array type handling.
  • #24468  Fixed constructor documentation in Python.

• Android：

  • New Android Archive Package (AAR) released via  Maven Central
  • New Android examples: QR code detector, video IO examples. DNN and face detector examples updated.
  • Switched to Gradle 7.6.3, the modern Android tool.

• Platform support:

  • #23021  Experimentally support CUDA as a first class language in CMake

• other:

  • TBD
  • OpenCV Summer of Code: HAN Liutong’s semi-automatic refactoring across multiple pull requests makes CPU-optimized code compatible with SIMD of variable vector length (RISC-V RVV)

See  ChangeLog for more details .