diff --git a/Dockerfile-core b/Dockerfile-core
index 073e5e1..443db85 100644
--- a/Dockerfile-core
+++ b/Dockerfile-core
@@ -18,6 +18,8 @@ RUN echo "APT::Acquire::Retries \"3\";" > /etc/apt/apt.conf.d/80-retries && \
 # XML utils
       libxml2-utils \
       xmlstarlet \
+# OCR-D uses ImageMagick for pixel density estimation
+      imagemagick \
     && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
diff --git a/Dockerfile-core-cuda10.0 b/Dockerfile-core-cuda10.0
index ede7d03..f1a2d60 100644
--- a/Dockerfile-core-cuda10.0
+++ b/Dockerfile-core-cuda10.0
@@ -18,6 +18,8 @@ RUN echo "APT::Acquire::Retries \"3\";" > /etc/apt/apt.conf.d/80-retries && \
 # XML utils
       libxml2-utils \
       xmlstarlet \
+# OCR-D uses ImageMagick for pixel density estimation
+      imagemagick \
     && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
diff --git a/Dockerfile-core-cuda10.1 b/Dockerfile-core-cuda10.1
index 96967db..569a567 100644
--- a/Dockerfile-core-cuda10.1
+++ b/Dockerfile-core-cuda10.1
@@ -18,6 +18,8 @@ RUN echo "APT::Acquire::Retries \"3\";" > /etc/apt/apt.conf.d/80-retries && \
 # XML utils
       libxml2-utils \
       xmlstarlet \
+# OCR-D uses ImageMagick for pixel density estimation
+      imagemagick \
     && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*