title: can't make work together opencv and kivy with buildozer on android smartphone
body: <p>I have a problem can't make work together opencv and kivy with buildozer on android smartphone. On pc works fine but when I packaging with buildozer and put in on android device it seems that opencv don't work properly and immediately crashes, I have already tried to grant permissions to camera but nothing, here is my code:</p>
  <pre><code>from kivy.app import App
  from kivy.uix.boxlayout import BoxLayout
  from kivy.uix.image import Image
  from kivy.graphics.texture import Texture
  from kivy.clock import Clock
  import cv2
  
  
  class MainApp(App):
      def video(self, *args):
          x, frame = self.cap.read()
          buffer = cv2.flip(frame, 0).tostring()
          texture = Texture.create(size=(frame.shape[1], frame.shape[0]), colorfmt='bgr')
          texture.blit_buffer(buffer, colorfmt='bgr', bufferfmt='ubyte')
          self.img.texture = texture
          
      def build(self):
          boxlayout = BoxLayout()
          self.img = Image()
          boxlayout.add_widget(self.img)
          self.cap = cv2.VideoCapture(0)
          Clock.schedule_interval(self.video, 1.0 / 30.0)
          return boxlayout
  
  if __name__ == '__main__':
      MainApp().run()
  </code></pre>
  <p>buildozer.spec file:</p>
  <pre><code>[app]
  
  # (str) Title of your application
  title = My Application
  
  # (str) Package name
  package.name = myapp
  
  # (str) Package domain (needed for android/ios packaging)
  package.domain = org.test
  
  # (str) Source code where the main.py live
  source.dir = .
  
  # (list) Source files to include (let empty to include all the files)
  source.include_exts = py,png,jpg,kv,atlas
  
  # (list) List of inclusions using pattern matching
  #source.include_patterns = assets/*,images/*.png
  
  # (list) Source files to exclude (let empty to not exclude anything)
  #source.exclude_exts = spec
  
  # (list) List of directory to exclude (let empty to not exclude anything)
  #source.exclude_dirs = tests, bin, venv
  
  # (list) List of exclusions using pattern matching
  # Do not prefix with './'
  #source.exclude_patterns = license,images/*/*.jpg
  
  # (str) Application versioning (method 1)
  version = 0.1
  
  # (str) Application versioning (method 2)
  # version.regex = __version__ = ['&quot;](.*)['&quot;]
  # version.filename = %(source.dir)s/main.py
  
  # (list) Application requirements
  # comma separated e.g. requirements = sqlite3,kivy
  requirements = python3,kivy,opencv,numpy
  
  # (str) Custom source folders for requirements
  # Sets custom source for any requirements with recipes
  # requirements.source.kivy = ../../kivy
  
  # (str) Presplash of the application
  #presplash.filename = %(source.dir)s/data/presplash.png
  
  # (str) Icon of the application
  #icon.filename = %(source.dir)s/data/icon.png
  
  # (str) Supported orientation (one of landscape, sensorLandscape, portrait or all)
  orientation = portrait
  
  # (list) List of service to declare
  #services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY
  
  #
  # OSX Specific
  #
  
  #
  # author = © Copyright Info
  
  # change the major version of python used by the app
  osx.python_version = 3
  
  # Kivy version to use
  osx.kivy_version = 1.9.1
  
  #
  # Android specific
  #
  
  # (bool) Indicate if the application should be fullscreen or not
  fullscreen = 0
  
  # (string) Presplash background color (for android toolchain)
  # Supported formats are: #RRGGBB #AARRGGBB or one of the following names:
  # red, blue, green, black, white, gray, cyan, magenta, yellow, lightgray,
  # darkgray, grey, lightgrey, darkgrey, aqua, fuchsia, lime, maroon, navy,
  # olive, purple, silver, teal.
  #android.presplash_color = #FFFFFF
  
  # (string) Presplash animation using Lottie format.
  # see https://lottiefiles.com/ for examples and https://airbnb.design/lottie/
  # for general documentation.
  # Lottie files can be created using various tools, like Adobe After Effect or Synfig.
  #android.presplash_lottie = &quot;path/to/lottie/file.json&quot;
  
  # (str) Adaptive icon of the application (used if Android API level is 26+ at runtime)
  #icon.adaptive_foreground.filename = %(source.dir)s/data/icon_fg.png
  #icon.adaptive_background.filename = %(source.dir)s/data/icon_bg.png
  
  # (list) Permissions
  android.permissions = CAMERA, READ_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE
  
  # (list) features (adds uses-feature -tags to manifest)
  #android.features = android.hardware.usb.host
  
  # (int) Target Android API, should be as high as possible.
  #android.api = 27
  
  # (int) Minimum API your APK / AAB will support.
  #android.minapi = 21
  
  # (int) Android SDK version to use
  #android.sdk = 20
  
  # (str) Android NDK version to use
  #android.ndk = 19b
  
  # (int) Android NDK API to use. This is the minimum API your app will support, it should usually match android.minapi.
  #android.ndk_api = 21
  
  # (bool) Use --private data storage (True) or --dir public storage (False)
  #android.private_storage = True
  
  # (str) Android NDK directory (if empty, it will be automatically downloaded.)
  #android.ndk_path =
  
  # (str) Android SDK directory (if empty, it will be automatically downloaded.)
  #android.sdk_path =
  
  # (str) ANT directory (if empty, it will be automatically downloaded.)
  #android.ant_path =
  
  # (bool) If True, then skip trying to update the Android sdk
  # This can be useful to avoid excess Internet downloads or save time
  # when an update is due and you just want to test/build your package
  # android.skip_update = False
  
  # (bool) If True, then automatically accept SDK license
  # agreements. This is intended for automation only. If set to False,
  # the default, you will be shown the license when first running
  # buildozer.
  # android.accept_sdk_license = False
  
  # (str) Android entry point, default is ok for Kivy-based app
  #android.entrypoint = org.kivy.android.PythonActivity
  
  # (str) Full name including package path of the Java class that implements Android Activity
  # use that parameter together with android.entrypoint to set custom Java class instead of PythonActivity
  #android.activity_class_name = org.kivy.android.PythonActivity
  
  # (str) Extra xml to write directly inside the &lt;manifest&gt; element of AndroidManifest.xml
  # use that parameter to provide a filename from where to load your custom XML code
  #android.extra_manifest_xml = ./src/android/extra_manifest.xml
  
  # (str) Extra xml to write directly inside the &lt;manifest&gt;&lt;application&gt; tag of AndroidManifest.xml
  # use that parameter to provide a filename from where to load your custom XML arguments:
  #android.extra_manifest_application_arguments = ./src/android/extra_manifest_application_arguments.xml
  
  # (str) Full name including package path of the Java class that implements Python Service
  # use that parameter to set custom Java class instead of PythonService
  #android.service_class_name = org.kivy.android.PythonService
  
  # (str) Android app theme, default is ok for Kivy-based app
  # android.apptheme = &quot;@android:style/Theme.NoTitleBar&quot;
  
  # (list) Pattern to whitelist for the whole project
  #android.whitelist =
  
  # (str) Path to a custom whitelist file
  #android.whitelist_src =
  
  # (str) Path to a custom blacklist file
  #android.blacklist_src =
  
  # (list) List of Java .jar files to add to the libs so that pyjnius can access
  # their classes. Don't add jars that you do not need, since extra jars can slow
  # down the build process. Allows wildcards matching, for example:
  # OUYA-ODK/libs/*.jar
  #android.add_jars = foo.jar,bar.jar,path/to/more/*.jar
  
  # (list) List of Java files to add to the android project (can be java or a
  # directory containing the files)
  #android.add_src =
  
  # (list) Android AAR archives to add
  #android.add_aars =
  
  # (list) Put these files or directories in the apk assets directory.
  # Either form may be used, and assets need not be in 'source.include_exts'.
  # 1) android.add_assets = source_asset_relative_path
  # 2) android.add_assets = source_asset_path:destination_asset_relative_path
  #android.add_assets =
  
  # (list) Gradle dependencies to add
  #android.gradle_dependencies =
  
  # (bool) Enable AndroidX support. Enable when 'android.gradle_dependencies'
  # contains an 'androidx' package, or any package from Kotlin source.
  # android.enable_androidx requires android.api &gt;= 28
  #android.enable_androidx = False
  
  # (list) add java compile options
  # this can for example be necessary when importing certain java libraries using the 'android.gradle_dependencies' option
  # see https://developer.android.com/studio/write/java8-support for further information
  # android.add_compile_options = &quot;sourceCompatibility = 1.8&quot;, &quot;targetCompatibility = 1.8&quot;
  
  # (list) Gradle repositories to add {can be necessary for some android.gradle_dependencies}
  # please enclose in double quotes 
  # e.g. android.gradle_repositories = &quot;maven { url 'https://kotlin.bintray.com/ktor' }&quot;
  #android.add_gradle_repositories =
  
  # (list) packaging options to add 
  # see https://google.github.io/android-gradle-dsl/current/com.android.build.gradle.internal.dsl.PackagingOptions.html
  # can be necessary to solve conflicts in gradle_dependencies
  # please enclose in double quotes 
  # e.g. android.add_packaging_options = &quot;exclude 'META-INF/common.kotlin_module'&quot;, &quot;exclude 'META-INF/*.kotlin_module'&quot;
  #android.add_packaging_options =
  
  # (list) Java classes to add as activities to the manifest.
  #android.add_activities = com.example.ExampleActivity
  
  # (str) OUYA Console category. Should be one of GAME or APP
  # If you leave this blank, OUYA support will not be enabled
  #android.ouya.category = GAME
  
  # (str) Filename of OUYA Console icon. It must be a 732x412 png image.
  #android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png
  
  # (str) XML file to include as an intent filters in &lt;activity&gt; tag
  #android.manifest.intent_filters =
  
  # (str) launchMode to set for the main activity
  #android.manifest.launch_mode = standard
  
  # (list) Android additional libraries to copy into libs/armeabi
  #android.add_libs_armeabi = libs/android/*.so
  #android.add_libs_armeabi_v7a = libs/android-v7/*.so
  #android.add_libs_arm64_v8a = libs/android-v8/*.so
  #android.add_libs_x86 = libs/android-x86/*.so
  #android.add_libs_mips = libs/android-mips/*.so
  
  # (bool) Indicate whether the screen should stay on
  # Don't forget to add the WAKE_LOCK permission if you set this to True
  #android.wakelock = False
  
  # (list) Android application meta-data to set (key=value format)
  #android.meta_data =
  
  # (list) Android library project to add (will be added in the
  # project.properties automatically.)
  #android.library_references =
  
  # (list) Android shared libraries which will be added to AndroidManifest.xml using &lt;uses-library&gt; tag
  #android.uses_library =
  
  # (str) Android logcat filters to use
  #android.logcat_filters = *:S python:D
  
  # (bool) Android logcat only display log for activity's pid
  #android.logcat_pid_only = False
  
  # (str) Android additional adb arguments
  #android.adb_args = -H host.docker.internal
  
  # (bool) Copy library instead of making a libpymodules.so
  #android.copy_libs = 1
  
  # (list) The Android archs to build for, choices: armeabi-v7a, arm64-v8a, x86, x86_64
  # In past, was `android.arch` as we weren't supporting builds for multiple archs at the same time.
  android.archs = arm64-v8a, armeabi-v7a
  
  # (int) overrides automatic versionCode computation (used in build.gradle)
  # this is not the same as app version and should only be edited if you know what you're doing
  # android.numeric_version = 1
  
  # (bool) enables Android auto backup feature (Android API &gt;=23)
  android.allow_backup = True
  
  # (str) XML file for custom backup rules (see official auto backup documentation)
  # android.backup_rules =
  
  # (str) If you need to insert variables into your AndroidManifest.xml file,
  # you can do so with the manifestPlaceholders property.
  # This property takes a map of key-value pairs. (via a string)
  # Usage example : android.manifest_placeholders = [myCustomUrl:\&quot;org.kivy.customurl\&quot;]
  # android.manifest_placeholders = [:]
  
  # (bool) disables the compilation of py to pyc/pyo files when packaging
  # android.no-compile-pyo = True
  
  # (str) The format used to package the app for release mode (aab or apk).
  # android.release_artifact = aab
  
  #
  # Python for android (p4a) specific
  #
  
  # (str) python-for-android URL to use for checkout
  #p4a.url =
  
  # (str) python-for-android fork to use in case if p4a.url is not specified, defaults to upstream (kivy)
  #p4a.fork = kivy
  
  # (str) python-for-android branch to use, defaults to master
  #p4a.branch = master
  
  # (str) python-for-android specific commit to use, defaults to HEAD, must be within p4a.branch
  #p4a.commit = HEAD
  
  # (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
  #p4a.source_dir =
  
  # (str) The directory in which python-for-android should look for your own build recipes (if any)
  #p4a.local_recipes =
  
  # (str) Filename to the hook for p4a
  #p4a.hook =
  
  # (str) Bootstrap to use for android builds
  # p4a.bootstrap = sdl2
  
  # (int) port number to specify an explicit --port= p4a argument (eg for bootstrap flask)
  #p4a.port =
  
  # Control passing the --use-setup-py vs --ignore-setup-py to p4a
  # &quot;in the future&quot; --use-setup-py is going to be the default behaviour in p4a, right now it is not
  # Setting this to false will pass --ignore-setup-py, true will pass --use-setup-py
  # NOTE: this is general setuptools integration, having pyproject.toml is enough, no need to generate
  # setup.py if you're using Poetry, but you need to add &quot;toml&quot; to source.include_exts.
  #p4a.setup_py = false
  
  # (str) extra command line arguments to pass when invoking pythonforandroid.toolchain
  #p4a.extra_args =
  
  
  #
  # iOS specific
  #
  
  # (str) Path to a custom kivy-ios folder
  #ios.kivy_ios_dir = ../kivy-ios
  # Alternately, specify the URL and branch of a git checkout:
  ios.kivy_ios_url = https://github.com/kivy/kivy-ios
  ios.kivy_ios_branch = master
  
  # Another platform dependency: ios-deploy
  # Uncomment to use a custom checkout
  #ios.ios_deploy_dir = ../ios_deploy
  # Or specify URL and branch
  ios.ios_deploy_url = https://github.com/phonegap/ios-deploy
  ios.ios_deploy_branch = 1.10.0
  
  # (bool) Whether or not to sign the code
  ios.codesign.allowed = false
  
  # (str) Name of the certificate to use for signing the debug version
  # Get a list of available identities: buildozer ios list_identities
  #ios.codesign.debug = &quot;iPhone Developer: &lt;lastname&gt; &lt;firstname&gt; (&lt;hexstring&gt;)&quot;
  
  # (str) The development team to use for signing the debug version
  #ios.codesign.development_team.debug = &lt;hexstring&gt;
  
  # (str) Name of the certificate to use for signing the release version
  #ios.codesign.release = %(ios.codesign.debug)s
  
  # (str) The development team to use for signing the release version
  #ios.codesign.development_team.release = &lt;hexstring&gt;
  
  # (str) URL pointing to .ipa file to be installed
  # This option should be defined along with `display_image_url` and `full_size_image_url` options.
  #ios.manifest.app_url =
  
  # (str) URL pointing to an icon (57x57px) to be displayed during download
  # This option should be defined along with `app_url` and `full_size_image_url` options.
  #ios.manifest.display_image_url =
  
  # (str) URL pointing to a large icon (512x512px) to be used by iTunes
  # This option should be defined along with `app_url` and `display_image_url` options.
  #ios.manifest.full_size_image_url =
  
  
  [buildozer]
  
  # (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
  log_level = 2
  
  # (int) Display warning if buildozer is run as root (0 = False, 1 = True)
  warn_on_root = 1
  
  # (str) Path to build artifact storage, absolute or relative to spec file
  # build_dir = ./.buildozer
  
  # (str) Path to build output (i.e. .apk, .aab, .ipa) storage
  # bin_dir = ./bin
  
  #    -----------------------------------------------------------------------------
  #    List as sections
  #
  #    You can define all the &quot;list&quot; as [section:key].
  #    Each line will be considered as a option to the list.
  #    Let's take [app] / source.exclude_patterns.
  #    Instead of doing:
  #
  #[app]
  #source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
  #
  #    This can be translated into:
  #
  #[app:source.exclude_patterns]
  #license
  #data/audio/*.wav
  #data/images/original/*
  #
  
  
  #    -----------------------------------------------------------------------------
  #    Profiles
  #
  #    You can extend section / key with a profile
  #    For example, you want to deploy a demo version of your application without
  #    HD content. You could first change the title to add &quot;(demo)&quot; in the name
  #    and extend the excluded directories to remove the HD content.
  #
  #[app@demo]
  #title = My Application (demo)
  #
  #[app:source.exclude_patterns@demo]
  #images/hd/*
  #
  #    Then, invoke the command line with the &quot;demo&quot; profile:
  #
  #buildozer --profile demo android debug
  </code></pre>