diff --git a/Dockerfile b/Dockerfile
index 01f2dcc..9cc2f5d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:focal
+FROM camicroscope/image-decoders:latest
 
 ### update
 ARG DEBIAN_FRONTEND=noninteractive
@@ -8,11 +8,10 @@ RUN apt-get -q -y dist-upgrade
 RUN apt-get clean
 RUN apt-get -q update
 
-RUN apt-get -q -y install git autoconf automake make libtool pkg-config cmake apache2 libapache2-mod-fcgid libfcgi0ldbl zlib1g-dev libpng-dev libjpeg-dev libtiff5-dev libgdk-pixbuf2.0-dev libxml2-dev libsqlite3-dev libcairo2-dev libglib2.0-dev g++ libmemcached-dev libjpeg-turbo8-dev
+RUN apt-get -q -y install git autoconf automake make libtool pkg-config apache2 libapache2-mod-fcgid libfcgi0ldbl g++ libmemcached-dev libjpeg-turbo8-dev
 RUN a2enmod rewrite
 RUN a2enmod fcgid
 
-RUN mkdir /root/src
 COPY . /root/src
 WORKDIR /root/src
 
@@ -29,32 +28,6 @@ RUN ln -s /etc/apache2/mods-available/proxy.conf /etc/apache2/mods-enabled/proxy
 COPY apache2.conf /etc/apache2/apache2.conf
 COPY ports.conf /etc/apache2/ports.conf
 
-WORKDIR /root/src
-
-### openjpeg version in ubuntu 14.04 is 1.3, too old and does not have openslide required chroma subsampled images support.  download 2.1.0 from source and build
-RUN git clone https://github.com/uclouvain/openjpeg.git --branch=v2.3.0
-RUN mkdir /root/src/openjpeg/build
-WORKDIR /root/src/openjpeg/build
-RUN cmake -DBUILD_JPIP=ON -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=Release -DBUILD_CODEC=ON -DBUILD_PKGCONFIG_FILES=ON ../
-RUN make
-RUN make install
-
-### Openslide
-WORKDIR /root/src
-## get my fork from openslide source cdoe
-RUN git clone https://github.com/openslide/openslide.git
-
-## build openslide
-WORKDIR /root/src/openslide
-RUN git checkout tags/v3.4.1
-RUN autoreconf -i
-#RUN ./configure --enable-static --enable-shared=no
-# may need to set OPENJPEG_CFLAGS='-I/usr/local/include' and OPENJPEG_LIBS='-L/usr/local/lib -lopenjp2'
-# and the corresponding TIFF flags and libs to where bigtiff lib is installed.
-RUN ./configure
-RUN make
-RUN make install
-
 ###  iipsrv
 WORKDIR /root/src/iipsrv
 RUN ./autogen.sh
diff --git a/iipsrv/src/IIPImage.cc b/iipsrv/src/IIPImage.cc
index a18887e..e4e3ba6 100644
--- a/iipsrv/src/IIPImage.cc
+++ b/iipsrv/src/IIPImage.cc
@@ -169,6 +169,7 @@ void IIPImage::testImageType() throw(file_error)
         suffix=="mrxs" || 
         suffix=="vms" || 
         suffix=="scn" || 
+        suffix=="dcm" || 
         suffix=="bif")
     	format = OPENSLIDE;
     else if( suffix == "jp2" || suffix == "jpx" || suffix == "j2k" ) format = JPEG2000;