add ffmpga support

Change-Id: I75829b20a5921f72bb0d2d41f5565babf90b912d

jdk/Dockerfile

@@ -21,6 +21,7 @@ COPY sources.list /etc/apt/sources.list
 RUN apt-get update \
     && apt-get install haveged -y \
     && apt-get -y install language-pack-zh-hans language-pack-zh-hans-base \
+    && apt-get -y install ffmpeg \
     && rm -rf /var/lib/apt/lists/*
 
 ADD server-jre-8u172-linux-x64.tar.gz /usr/local/
@@ -40,3 +41,4 @@ ENV LC_ALL zh_CN.UTF-8
 ENV JAVA_HOME /usr/local/jdk1.8.0_172
 ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
 ENV PATH $PATH:$JAVA_HOME/bin
+ENV FFMPEG /usr/bin/ffmpeg