title: App build failed
body: <p>I didn't have any problem like this before. But, now I'm encountering this error while trying to build my project:</p>
  
  <pre><code>Error:Execution failed for task ':libraries:opencv:compileReleaseJavaWithJavac'.
  &gt; null value in entry: destinationDir=null
  </code></pre>
  
  <p>Here is more info I think can be relevant: </p>
  
  <pre><code> Starting to execute task ':libraries:opencv:generateReleaseSources'
  11:12:36.146 [INFO] [org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter] Skipping task ':libraries:opencv:generateReleaseSources' as it has no actions.
  11:12:36.146 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Finished executing task ':libraries:opencv:generateReleaseSources'
  11:12:36.146 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:generateReleaseSources (Thread[Daemon worker Thread 8,5,main]) completed. Took 0.0 secs.
  11:12:36.146 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.45 started (2 in use).
  11:12:36.146 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:incrementalReleaseJavaCompilationSafeguard (Thread[Task worker,5,main]) started.
  11:12:36.146 [LIFECYCLE] [class org.gradle.internal.buildevents.TaskExecutionLogger] :libraries:opencv:incrementalReleaseJavaCompilationSafeguard
  11:12:36.146 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Starting to execute task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard'
  11:12:36.147 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.44 completed (1 in use)
  11:12:36.164 [INFO] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Putting task artifact state for task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard' into context took 0.017 secs.
  11:12:36.242 [DEBUG] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Determining if task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard' is up-to-date
  11:12:36.242 [INFO] [org.gradle.api.internal.changedetection.rules.TaskTypeTaskStateChanges] Task :libraries:opencv:incrementalReleaseJavaCompilationSafeguard class loader hash: 7e6e9bf7a8a439398628229ea2c7266a
  11:12:36.242 [INFO] [org.gradle.api.internal.changedetection.rules.TaskTypeTaskStateChanges] Task :libraries:opencv:incrementalReleaseJavaCompilationSafeguard actions class loader hash: 8605ffca8bc4a746469163f1432ce86d
  11:12:36.349 [INFO] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Executing task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard' (up-to-date check took 0.107 secs) due to:
    Task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard' class path has changed from e6418cb36f855e1919b4fe4b69c7feba to 7e6e9bf7a8a439398628229ea2c7266a.
  11:12:36.349 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter] Executing actions for task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard'.
  11:12:36.351 [INFO] [org.gradle.api.internal.changedetection.changes.RebuildIncrementalTaskInputs] All input files are considered out-of-date for incremental task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard'.
  11:12:36.351 [DEBUG] [org.gradle.api.Task] Removing old bits to force javac non incremental mode.
  11:12:36.418 [DEBUG] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Removed task artifact state for {} from context.
  11:12:36.418 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Finished executing task ':libraries:opencv:incrementalReleaseJavaCompilationSafeguard'
  11:12:36.419 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:incrementalReleaseJavaCompilationSafeguard (Thread[Task worker,5,main]) completed. Took 0.272 secs.
  11:12:36.419 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.46 started (2 in use).
  11:12:36.419 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:javaPreCompileRelease (Thread[Task worker Thread 6,5,main]) started.
  11:12:36.419 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.45 completed (1 in use)
  11:12:36.419 [LIFECYCLE] [class org.gradle.internal.buildevents.TaskExecutionLogger] :libraries:opencv:javaPreCompileRelease
  11:12:36.419 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Starting to execute task ':libraries:opencv:javaPreCompileRelease'
  11:12:36.419 [INFO] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Putting task artifact state for task ':libraries:opencv:javaPreCompileRelease' into context took 0.0 secs.
  11:12:36.419 [DEBUG] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Determining if task ':libraries:opencv:javaPreCompileRelease' is up-to-date
  11:12:36.419 [INFO] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Executing task ':libraries:opencv:javaPreCompileRelease' (up-to-date check took 0.0 secs) due to:
    Task has not declared any outputs.
  11:12:36.419 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter] Executing actions for task ':libraries:opencv:javaPreCompileRelease'.
  11:12:36.424 [DEBUG] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Removed task artifact state for {} from context.
  11:12:36.424 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Finished executing task ':libraries:opencv:javaPreCompileRelease'
  11:12:36.424 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:javaPreCompileRelease (Thread[Task worker Thread 6,5,main]) completed. Took 0.005 secs.
  11:12:36.424 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.47 started (2 in use).
  11:12:36.424 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:compileReleaseJavaWithJavac (Thread[Task worker Thread 7,5,main]) started.
  11:12:36.424 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.46 completed (1 in use)
  11:12:36.424 [LIFECYCLE] [class org.gradle.internal.buildevents.TaskExecutionLogger] :libraries:opencv:compileReleaseJavaWithJavac
  11:12:36.424 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Starting to execute task ':libraries:opencv:compileReleaseJavaWithJavac'
  11:12:36.436 [INFO] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Putting task artifact state for task ':libraries:opencv:compileReleaseJavaWithJavac' into context took 0.011 secs.
  11:12:36.561 [DEBUG] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Determining if task ':libraries:opencv:compileReleaseJavaWithJavac' is up-to-date
  11:12:36.561 [INFO] [org.gradle.api.internal.changedetection.rules.TaskTypeTaskStateChanges] Task :libraries:opencv:compileReleaseJavaWithJavac class loader hash: 7e6e9bf7a8a439398628229ea2c7266a
  11:12:36.561 [INFO] [org.gradle.api.internal.changedetection.rules.TaskTypeTaskStateChanges] Task :libraries:opencv:compileReleaseJavaWithJavac actions class loader hash: 18198991b357e4282b88db10fdb1e992
  11:12:36.768 [INFO] [org.gradle.api.internal.file.collections.DirectoryFileTree] file or directory 'Q:\Malaria\AndroidProject\NLM_Malaria_Screener\libraries\opencv\src\release\java', not found
  11:12:36.849 [DEBUG] [org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter] Removed task artifact state for {} from context.
  11:12:36.849 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter] Finished executing task ':libraries:opencv:compileReleaseJavaWithJavac'
  11:12:36.849 [LIFECYCLE] [class org.gradle.internal.buildevents.TaskExecutionLogger] :libraries:opencv:compileReleaseJavaWithJavac FAILED
  11:12:36.849 [INFO] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] :libraries:opencv:compileReleaseJavaWithJavac (Thread[Task worker Thread 7,5,main]) completed. Took 0.426 secs.
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 6,5,main]] finished, busy: 0.057 secs, idle: 4.282 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker,5,main]] finished, busy: 0.402 secs, idle: 3.937 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 3,5,main]] finished, busy: 0.538 secs, idle: 3.801 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 5,5,main]] finished, busy: 0.763 secs, idle: 3.576 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 4,5,main]] finished, busy: 0.171 secs, idle: 4.168 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 2,5,main]] finished, busy: 0.573 secs, idle: 3.766 secs
  11:12:36.849 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Daemon worker Thread 8,5,main]] finished, busy: 0.247 secs, idle: 4.092 secs
  11:12:36.849 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry] Worker root.47 completed (0 in use)
  11:12:36.850 [DEBUG] [org.gradle.execution.taskgraph.AbstractTaskPlanExecutor] Task worker [Thread[Task worker Thread 7,5,main]] finished, busy: 2.221 secs, idle: 2.118 secs
  11:12:36.850 [ERROR] [org.gradle.internal.buildevents.BuildExceptionReporter]
  11:12:36.850 [ERROR] [org.gradle.internal.buildevents.BuildExceptionReporter] FAILURE: Build failed with an exception.
  11:12:36.850 [ERROR] [org.gradle.internal.buildevents.BuildExceptionReporter]
  11:12:36.850 [ERROR] [org.gradle.internal.buildevents.BuildExceptionReporter] * What went wrong:
  11:12:36.850 [ERROR] [org.gradle.internal.buildevents.BuildExceptionReporter] null value in entry: destinationDir=null
  </code></pre>
  
  <p>I don't know what "destinationDir" is... Please let me know where the problem may resides in, thanks!</p>
  
  <p>With "-s":</p>
  
  <pre><code>* What went wrong:
  null value in entry: destinationDir=null
  
  * Try:
  Run with --info or --debug option to get more log output.
  
  * Exception is:
  java.lang.NullPointerException: null value in entry: destinationDir=null
          at com.google.common.collect.CollectPreconditions.checkEntryNotNull(CollectPreconditions.java:33)
          at com.google.common.collect.ImmutableMap.entryOf(ImmutableMap.java:135)
          at com.google.common.collect.ImmutableMap$Builder.put(ImmutableMap.java:206)
          at com.google.common.collect.ImmutableSortedMap$Builder.put(ImmutableSortedMap.java:371)
          at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$LazyTaskExecution.getOutputFilesSnapshot(CacheBackedTaskHistoryRepository.java:327)
          at org.gradle.api.internal.changedetection.rules.OutputFilesTaskStateChanges.getPrevious(OutputFilesTaskStateChanges.java:39)
          at org.gradle.api.internal.changedetection.rules.AbstractNamedFileSnapshotTaskStateChanges.iterator(AbstractNamedFileSnapshotTaskStateChanges.java:98)
          at org.gradle.api.internal.changedetection.rules.OutputFilesTaskStateChanges.iterator(OutputFilesTaskStateChanges.java:29)
          at org.gradle.api.internal.changedetection.rules.CachingTaskStateChanges.reset(CachingTaskStateChanges.java:79)
          at org.gradle.api.internal.changedetection.rules.CachingTaskStateChanges.iterator(CachingTaskStateChanges.java:44)
          at org.gradle.api.internal.changedetection.rules.SummaryTaskStateChanges.firstDirtyIterator(SummaryTaskStateChanges.java:63)
          at org.gradle.api.internal.changedetection.rules.SummaryTaskStateChanges.access$000(SummaryTaskStateChanges.java:25)
          at org.gradle.api.internal.changedetection.rules.SummaryTaskStateChanges$1.computeNext(SummaryTaskStateChanges.java:49)
          at org.gradle.api.internal.changedetection.rules.SummaryTaskStateChanges$1.computeNext(SummaryTaskStateChanges.java:42)
          at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143)
          at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138)
          at org.gradle.api.internal.changedetection.changes.DefaultTaskArtifactStateRepository$TaskArtifactStateImpl.collectChangedMessages(DefaultTaskArtifactStateRepository.java:88)
          at org.gradle.api.internal.changedetection.changes.DefaultTaskArtifactStateRepository$TaskArtifactStateImpl.isUpToDate(DefaultTaskArtifactStateRepository.java:79)
          at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:51)
          at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
          at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:88)
          at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:46)
          at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:51)
          at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
          at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
          at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
          at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.execute(DefaultTaskGraphExecuter.java:236)
          at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.execute(DefaultTaskGraphExecuter.java:228)
          at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
          at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
          at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:61)
          at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:228)
          at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:215)
          at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:77)
          at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:58)
          at org.gradle.execution.taskgraph.ParallelTaskPlanExecutor.process(ParallelTaskPlanExecutor.java:50)
          at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:113)
          at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
          at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
          at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
          at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
          at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
          at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
          at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
          at org.gradle.initialization.DefaultGradleLauncher$3.execute(DefaultGradleLauncher.java:196)
          at org.gradle.initialization.DefaultGradleLauncher$3.execute(DefaultGradleLauncher.java:193)
          at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
          at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
          at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:56)
          at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:193)
          at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:119)
          at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:102)
          at org.gradle.launcher.exec.GradleBuildController.run(GradleBuildController.java:71)
          at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
          at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
          at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:41)
          at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
          at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:75)
          at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:49)
          at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:44)
          at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:29)
          at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
          at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:47)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
          at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
          at org.gradle.util.Swapper.swap(Swapper.java:38)
          at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
          at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:72)
          at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
          at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
          at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
          at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:297)
          at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
          at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
  </code></pre>
  
  <p>I have three build scripts:</p>
  
  <ol>
  <li><p>top level: </p>
  
  <p>// Top-level build file where you can add configuration options common to all sub-projects/modules.</p>
  
  <pre><code>buildscript {
      repositories {
          jcenter()
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:2.3.1'
  
          // NOTE: Do not place your application dependencies here; they belong
          // in the individual module build.gradle files
      }
  }
  
  allprojects {
      repositories {
          jcenter()
      }
  
  }
  </code></pre></li>
  <li><p>app</p></li>
  </ol>
  
  <p><a href="https://i.stack.imgur.com/R2xBK.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/R2xBK.jpg" alt="enter image description here"></a></p>
  
  <ol start="3">
  <li>opencv</li>
  </ol>
  
  <p><a href="https://i.stack.imgur.com/zsYdR.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zsYdR.jpg" alt="enter image description here"></a></p>