Recherche avancée

Sur d’autres sites (10620)

• ffmpeg4.4 missing in OpenCV3.4.13 + Android Studio4.2.1 ? No tutorial gives answer how to fix

  8 juin 2021, par Fab

  Finally opencv is working in my Android Studio project (solved with help of https://www.youtube.com/watch?v=-0Yx1UzozzQ). But theres is no Video I/O information visible so I guess i didnt connected ffmpeg correctly in my project and it isnt used at all !?

  


  My steps so far :

  


  


  • ffmpeg download : https://www.videohelp.com/software/ffmpeg

    


  


  • added ffmpeg to path like explained here :
https://soundartifacts.com/how-to/186-how-to-install-ffmpeg-on-windows-10-amp-add-ffmpeg-to-windows-path.html#video
powershell shows installation.

    


  


  • when printing Core.getBuildInformation() in the project I see that the Video I/O section is empty and I assume there has to be some information about FFMPEG etc...see picture :
enter image description here

    


  


  


  

  • I dont get any error messages. I try to VideoCapture.open("somestring") and returned is just false.

  


  


  I know there are a lot of similar questions but I cant identify which one really addresses my issue.
Really appreciate your help. Thanks, Fabian

  


• Android.mk : how to include ffmpeg and Opencv

  28 janvier 2013, par Mark

  this is my project situation : I compiled ffmpeg in windows using this tutorial and I imported the ffmpeg folder (with inside libffmpeg.so file) generated inside my android project (under jni folder).
  In my project I have a jni_part.cpp where I inserted my jni function to operate with opencv.
  In my Android.mk I'm using the code below to import opencv and compile the jni_part.cpp

  include $(CLEAR_VARS)
  
  include ../../sdk/native/jni/OpenCV.mk
  
  LOCAL_MODULE    := mixed_sample
  
  LOCAL_SRC_FILES := jni_part.cpp
  
  LOCAL_LDLIBS +=  -llog -ldl 
  
  LOCAL_SHARED_LIBRARY := ffmpeg-prebuilt
  
  include $(BUILD_SHARED_LIBRARY)

  But what code I should use to import also ffmpeg ? I tried to use this code :

  include $(CLEAR_VARS)
  
  LOCAL_MODULE := ffmpeg-prebuilt
  
  LOCAL_SRC_FILES := ffmpeg-0.8/android/armv7-a/libffmpeg.so
  
  LOCAL_EXPORT_C_INCLUDES := ffmpeg-0.8/android/armv7-a/include/
  
  LOCAL_EXPORT_LDLIBS := ffmpeg-0.8/android/armv7-a/libffmpeg.so
  
  LOCAL_PRELINK_MODULE := true
  
  include $(PREBUILT_SHARED_LIBRARY)

  but if from my jni_part.cpp code I try to include some ffmpeg files/libraries "#include <libavutil></libavutil>avstring.h>" I get this error :

  **** Build of configuration Default for project OpenCV Tutorial 4 - Mix Java+Native OpenCV ****
  
  
  
  C:\android-ndk-r8c\ndk-build.cmd 
  
  Prebuilt       : libffmpeg.so <= jni/ffmpeg-0.8/android/armv7-a/
  
  Install        : libffmpeg.so => libs/armeabi-v7a/libffmpeg.so
  
  "Compile++ thumb : mixed_sample <= jni_part.cpp
  
  jni/jni_part.cpp:24:32: fatal error: libavutil/avstring.h: No such file or directory
  
  compilation terminated.
  
  make: *** [obj/local/armeabi-v7a/objs/mixed_sample/jni_part.o] Error 1
  
  
  
  **** Build Finished ****

  Someone could help me please ? I need to do this to include ffmpeg codec with the hope to use the function cvCaptureFromAVi...
  Thanks in advance

• How to bind ffmpeg4.4 to OpenCV3.4.13 to work in Android Studio4.2.1 (Java)

  8 juin 2021, par Fab

  Finally opencv is working in my Android Studio project (solved with help of https://www.youtube.com/watch?v=-0Yx1UzozzQ). But theres is no Video I/O information visible so I guess i didnt connected ffmpeg correctly in my project and it isnt used at all !?

  


  My steps so far :

  


  


  • ffmpeg download : https://www.videohelp.com/software/ffmpeg

    


  


  • added ffmpeg to path like explained here :
https://soundartifacts.com/how-to/186-how-to-install-ffmpeg-on-windows-10-amp-add-ffmpeg-to-windows-path.html#video
. Powershell shows that ffmpeg is installed.

    


  


  • when printing Core.getBuildInformation() in the project I see that the Video I/O section is empty and I assume there has to be some information about FFMPEG etc...see picture :
enter image description here

    


  


  


  

  • I dont get any error messages. I try to VideoCapture.open("somestring") and return value is always false.

  


  


  I know there are a lot of similar questions but I cant identify which one really addresses my issue.
Really appreciate your help. Thanks, Fabian