Puoi controllare le informazioni sulla build di OpenCV con getBuildInformation().
Se il codice esempio di libri o siti Web non funziona, verificare che le funzionalità necessarie siano abilitate.
In questo articolo vengono descritti i seguenti contenuti.
- Se hai problemi con OpenCV, controlla le informazioni sulla build
- Ottieni informazioni sulla build di OpenCV:
getBuildInformation() - Esempio di codice in Python
- Verifica con il codice
- Verifica con la riga di comando
Se hai problemi con OpenCV, controlla le informazioni sulla build
OpenCV ha molte funzionalità, ma alcune di esse devono essere abilitate in fase di compilazione.
Se copi e incolli un codice di esempio da libri o siti Web e non funziona correttamente, non è perché il codice è sbagliato, è perché l’ambiente in cui lo stai provando non ha abilitato le funzionalità necessarie.
Ad esempio, il supporto per I/O video, CUDA e Qt deve essere in fase di compilazione.
Ottieni informazioni sulla build di OpenCV:getBuildInformation()
Puoi controllare le informazioni sulla build di OpenCV con getBuildInformation().
getBuildInformation() contiene le informazioni di compilazione come stringa.
Esempio di codice in Python
Verifica con il codice
Puoi controllare le informazioni sulla build come segue:
import cv2
print(cv2.getBuildInformation())
#
# General configuration for OpenCV 4.0.1 =====================================
# Version control: unknown
#
# Extra modules:
# Location (extra): /tmp/opencv-20190105-31032-o160to/opencv-4.0.1/opencv_contrib/modules
# Version control (extra): unknown
#
# Platform:
# Timestamp: 2019-01-05T01:41:15Z
# Host: Darwin 18.2.0 x86_64
# CMake: 3.13.2
# CMake generator: Unix Makefiles
# CMake build tool: /usr/local/Homebrew/Library/Homebrew/shims/mac/super/gmake
# Configuration: Release
#
# CPU/HW features:
# Baseline: SSE SSE2 SSE3 SSSE3 SSE4_1 POPCNT SSE4_2
# requested: DETECT
# disabled: SSE4_1 SSE4_2 AVX AVX2
# Dispatched code generation: SSE4_1 SSE4_2 FP16 AVX AVX2 AVX512_SKX
# requested: SSE4_1 SSE4_2 AVX FP16 AVX2 AVX512_SKX
# SSE4_1 (0 files): +
# SSE4_2 (0 files): +
# FP16 (0 files): + FP16 AVX
# AVX (4 files): + AVX
# AVX2 (11 files): + FP16 FMA3 AVX AVX2
# AVX512_SKX (1 files): + FP16 FMA3 AVX AVX2 AVX_512F AVX512_SKX
#
# C/C++:
# Built as dynamic libs?: YES
# C++ Compiler: /usr/local/Homebrew/Library/Homebrew/shims/mac/super/clang++ (ver 10.0.0.10001145)
# C++ flags (Release): -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Wno-long-long -Qunused-arguments -Wno-semicolon-before-method-body -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -DNDEBUG -DNDEBUG
# C++ flags (Debug): -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Wno-long-long -Qunused-arguments -Wno-semicolon-before-method-body -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -g -O0 -DDEBUG -D_DEBUG
# C Compiler: /usr/local/Homebrew/Library/Homebrew/shims/mac/super/clang
# C flags (Release): -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Wno-long-long -Qunused-arguments -Wno-semicolon-before-method-body -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -DNDEBUG -DNDEBUG
# C flags (Debug): -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Wno-long-long -Qunused-arguments -Wno-semicolon-before-method-body -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -g -O0 -DDEBUG -D_DEBUG
# Linker flags (Release):
# Linker flags (Debug):
# ccache: NO
# Precompiled headers: NO
# Extra dependencies:
# 3rdparty dependencies:
#
# OpenCV modules:
# To be built: aruco bgsegm bioinspired calib3d ccalib core datasets dnn dnn_objdetect dpm face features2d flann fuzzy gapi hfs highgui img_hash imgcodecs imgproc java_bindings_generator line_descriptor ml objdetect optflow phase_unwrapping photo plot python2 python3 python_bindings_generator reg rgbd saliency shape stereo stitching structured_light superres surface_matching tracking video videoio videostab xfeatures2d ximgproc xobjdetect xphoto
# Disabled: text world
# Disabled by dependency: -
# Unavailable: cnn_3dobj cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev cvv freetype hdf java js matlab ovis sfm ts viz
# Applications: apps
# Documentation: NO
# Non-free algorithms: YES
#
# GUI:
# Cocoa: YES
#
# Media I/O:
# ZLib: /usr/lib/libz.dylib (ver 1.2.11)
# JPEG: build-libjpeg-turbo (ver 1.5.3-62)
# WEBP: build (ver encoder: 0x020e)
# PNG: /usr/local/lib/libpng.dylib (ver 1.6.36)
# TIFF: /usr/local/lib/libtiff.dylib (ver 42 / 4.0.10)
# OpenEXR: /usr/local/lib/libImath.dylib /usr/local/lib/libIlmImf.dylib /usr/local/lib/libIex.dylib /usr/local/lib/libHalf.dylib /usr/local/lib/libIlmThread.dylib (ver 2.2.0)
# HDR: YES
# SUNRASTER: YES
# PXM: YES
# PFM: YES
#
# Video I/O:
# FFMPEG: YES
# avcodec: YES (ver 58.35.100)
# avformat: YES (ver 58.20.100)
# avutil: YES (ver 56.22.100)
# swscale: YES (ver 5.3.100)
# avresample: YES (ver 4.0.0)
# AVFoundation: YES
#
# Parallel framework: TBB (ver 2019.0 interface 11003)
#
# Trace: YES (with Intel ITT)
#
# Other third-party libraries:
# Intel IPP: 2019.0.0 Gold [2019.0.0]
# at: /tmp/opencv-20190105-31032-o160to/opencv-4.0.1/build/3rdparty/ippicv/ippicv_mac/icv
# Intel IPP IW: sources (2019.0.0)
# at: /tmp/opencv-20190105-31032-o160to/opencv-4.0.1/build/3rdparty/ippicv/ippicv_mac/iw
# Lapack: YES (/usr/local/opt/openblas/lib/libopenblas.dylib /usr/local/opt/openblas/lib/libopenblas.dylib)
# Eigen: YES (ver 3.3.7)
# Custom HAL: NO
# Protobuf: build (3.5.1)
#
# OpenCL: YES (no extra features)
# Include path: NO
# Link libraries: -framework OpenCL
#
# Python 2:
# Interpreter: /usr/local/opt/python@2/bin/python (ver 2.7.15)
# Libraries: /usr/local/Cellar/python@2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/lib/libpython2.7.dylib (ver 2.7.15)
# numpy: /usr/local/lib/python2.7/site-packages/numpy/core/include (ver 1.15.4)
# install path: lib/python2.7/site-packages/cv2/python-2.7
#
# Python 3:
# Interpreter: /usr/local/opt/python/bin/python3 (ver 3.7.2)
# Libraries: /usr/local/opt/python/Frameworks/Python.framework/Versions/3.7/lib/python3.7/config-3.7m-darwin/libpython3.7.dylib (ver 3.7.2)
# numpy: /usr/local/lib/python3.7/site-packages/numpy/core/include (ver 1.15.4)
# install path: lib/python3.7/site-packages/cv2/python-3.7
#
# Python (for build): /usr/local/opt/python@2/bin/python
#
# Java:
# ant: NO
# JNI: /Library/Java/JavaVirtualMachines/openjdk-11.0.1.jdk/Contents/Home/include /Library/Java/JavaVirtualMachines/openjdk-11.0.1.jdk/Contents/Home/include/darwin /Library/Java/JavaVirtualMachines/openjdk-11.0.1.jdk/Contents/Home/include
# Java wrappers: NO
# Java tests: NO
#
# Install to: /usr/local/Cellar/opencv/4.0.1
# -----------------------------------------------------------------
getBuildInformation() restituisce str.
print(type(cv2.getBuildInformation()))
# <class 'str'>
Verifica con la riga di comando
Il comando python (o python3) può eseguire il codice direttamente con l’opzione -c.
Puoi controllare le informazioni sulla build di OpenCV eseguendo il seguente comando in un terminale.
$ python3 -c 'import cv2; print(cv2.getBuildInformation())'
[ ... ]
È conveniente usare pipe e reindirizzamento quando lo esegui sulla riga di comando.
Ad esempio, se grep è disponibile, puoi controllare l’elemento desiderato come segue:
$ python3 -c 'import cv2; print(cv2.getBuildInformation())' | grep FFMPEG
FFMPEG: YES
$ python3 -c 'import cv2; print(cv2.getBuildInformation())' | grep Video -A10
Video I/O:
FFMPEG: YES
avcodec: YES (ver 58.35.100)
avformat: YES (ver 58.20.100)
avutil: YES (ver 56.22.100)
swscale: YES (ver 5.3.100)
avresample: YES (ver 4.0.0)
AVFoundation: YES
Parallel framework: TBB (ver 2019.0 interface 11003)