opencv - java.library.path hadoop 中没有 libopencv_core.so

Question

我在 hadoop 中工作，当我为我的图像处理程序创建可运行的 jar 时，突然发生了这个错误，它与 opencv native 库路径有关

在使用 eclipse 时我可以设置路径:

//System.loadLibrary(Core.NATIVE_LIBRARY_NAME);

但是在使用 hadoop 执行可运行的 jar 时它会出错。谁能指正一下？

    hduser@master:/home/mnh/Desktop$ hadoop jar  opencv19.jar /usr/local/hadoop/input/cars.mp4 /usr/local/hadoop/cars89
17/06/07 16:15:37 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
17/06/07 16:15:39 INFO client.RMProxy: Connecting to ResourceManager at master/192.168.137.52:8050
17/06/07 16:15:40 WARN mapreduce.JobSubmitter: Hadoop command-line option parsing not performed. Implement the Tool interface and execute your application with ToolRunner to remedy this.
17/06/07 16:16:08 INFO input.FileInputFormat: Total input paths to process : 1
17/06/07 16:16:08 INFO mapreduce.JobSubmitter: number of splits:1
17/06/07 16:16:09 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1496831815466_0009
17/06/07 16:16:09 INFO impl.YarnClientImpl: Submitted application application_1496831815466_0009
17/06/07 16:16:09 INFO mapreduce.Job: The url to track the job: http://master:8088/proxy/application_1496831815466_0009/
17/06/07 16:16:09 INFO mapreduce.Job: Running job: job_1496831815466_0009
17/06/07 16:16:20 INFO mapreduce.Job: Job job_1496831815466_0009 running in uber mode : false
17/06/07 16:16:20 INFO mapreduce.Job:  map 0% reduce 0%
17/06/07 16:16:29 INFO mapreduce.Job: Task Id : attempt_1496831815466_0009_m_000000_0, Status : FAILED
Error: no libopencv_core.so in java.library.path
17/06/07 16:16:37 INFO mapreduce.Job: Task Id : attempt_1496831815466_0009_m_000000_1, Status : FAILED
Error: no libopencv_core.so in java.library.path
17/06/07 16:16:45 INFO mapreduce.Job: Task Id : attempt_1496831815466_0009_m_000000_2, Status : FAILED
Error: no libopencv_core.so in java.library.path
17/06/07 16:16:54 INFO mapreduce.Job:  map 100% reduce 100%
17/06/07 16:16:55 INFO mapreduce.Job: Job job_1496831815466_0009 failed with state FAILED due to: Task failed task_1496831815466_0009_m_000000
Job failed as tasks failed. failedMaps:1 failedReduces:0

17/06/07 16:16:56 INFO mapreduce.Job: Counters: 12
    Job Counters 
        Failed map tasks=4
        Launched map tasks=4
        Other local map tasks=3
        Data-local map tasks=1
        Total time spent by all maps in occupied slots (ms)=26582
        Total time spent by all reduces in occupied slots (ms)=0
        Total time spent by all map tasks (ms)=26582
        Total vcore-seconds taken by all map tasks=26582
        Total megabyte-seconds taken by all map tasks=27219968
    Map-Reduce Framework
        CPU time spent (ms)=0
        Physical memory (bytes) snapshot=0
        Virtual memory (bytes) snapshot=0

Answer 1

您收到的错误消息与工作人员无法使用 OpenCV 有关，因为它没有安装在相应的机器上。所以解决方案是在安装了 Nodemanager 组件的集群机器上安装 OpenCV(那些将执行任务的机器)。为了能够使用 System.loadLibrary() 方法加载库，您需要将 so 文件的位置添加到 PATH系统变量。