From 2b63ba9e59c72c0570425591387da3e0e57de854 Mon Sep 17 00:00:00 2001
From: Patrick Jentsch <pjentsch@sfb1288inf-Laptop.fritz.box>
Date: Wed, 1 Jul 2020 11:03:34 +0200
Subject: [PATCH] Remove unused dependencies and use ghostscript for image
 split

---
 Dockerfile |  1 -
 ocr        | 39 ++++++++++++++++++++++++---------------
 2 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index d924438..66b86a0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -14,7 +14,6 @@ RUN apt-get update \
       ca-certificates \
       gnupg2 \
       ghostscript \
-      imagemagick \
       poppler-utils \
       python2.7 \
       python3.7 \
diff --git a/ocr b/ocr
index f26f8d4..020d200 100755
--- a/ocr
+++ b/ocr
@@ -98,12 +98,16 @@ class OCRPipeline(WorkflowRunner):
         n_cores = min(self.n_cores, max(1, int(self.n_cores / len(self.jobs))))
         for i, job in enumerate(self.jobs):
             output_dir = os.path.join(job.output_dir, 'tmp')
-            output_file_base = os.path.join(output_dir, 'page')
-            cmd = 'pdftoppm'
-            cmd += ' -r 300'
-            cmd += ' -tiff'
-            cmd += ' -tiffcompression lzw'
-            cmd += ' "{}" "{}"'.format(job.file, output_file_base)
+            cmd = 'gs'
+            cmd += ' -dBATCH'
+            cmd += ' -dNOPAUSE'
+            cmd += ' -dNumRenderingThreads={}'.format(n_cores)
+            cmd += ' -dQUIET'
+            cmd += ' -r300'
+            cmd += ' -sDEVICE=tiff24nc'
+            cmd += ' -sCompression=lzw'
+            cmd += ' "-sOutputFile={}/page-%d.tif"'.format(output_dir)
+            cmd += ' "{}"'.format(job.file)
             deps = 'setup_output_directory_-_{}'.format(i)
             lbl = 'split_input_-_{}'.format(i)
             split_input_jobs.append(self.addTask(command=cmd,
@@ -138,8 +142,9 @@ class OCRPipeline(WorkflowRunner):
                 files.sort(key=lambda x: int(re.search(r'\d+', x).group(0)))
                 files = map(lambda x: os.path.join(input_dir, x), files)
                 cmd = 'ocropus-nlbin "{}"'.format('" "'.join(files))
-                cmd += ' -o "{}"'.format(output_dir)
-                cmd += ' -Q "{}"'.format(n_cores)
+                cmd += ' --nocheck'
+                cmd += ' --output "{}"'.format(output_dir)
+                cmd += ' --parallel "{}"'.format(n_cores)
                 deps = 'split_input_-_{}'.format(i)
                 lbl = 'binarization_-_{}'.format(i)
                 binarization_jobs.append(self.addTask(command=cmd,
@@ -322,19 +327,22 @@ class OCRPipeline(WorkflowRunner):
         ' ##################################################
         '''
         pdf_compression_jobs = []
+        n_cores = min(self.n_cores, max(1, int(self.n_cores / len(self.jobs))))
         if self.compress:
             for i, job in enumerate(self.jobs):
                 file = filter(lambda x: x.endswith('.pdf'), os.listdir(job.output_dir))[0]  # noqa
                 original_file = os.path.join(job.output_dir, file)
                 compressed_file = os.path.join(job.output_dir, 'c_' + file)
                 cmd = 'gs'
-                cmd += ' -sDEVICE=pdfwrite'
-                cmd += ' -dCompatibilityLevel=1.4'
-                cmd += ' -dPDFSETTINGS=/ebook'
-                cmd += ' -dNOPAUSE'
-                cmd += ' -dQUIET'
                 cmd += ' -dBATCH'
-                cmd += ' -sOutputFile="{}"'.format(compressed_file)
+                cmd += ' -dNOPAUSE'
+                cmd += ' -dNumRenderingThreads={}'.format(n_cores)
+                cmd += ' -dPDFSETTINGS=/ebook'
+                # -dCompatibilityLevel must be defined after -dPDFSETTINGS
+                cmd += ' -dCompatibilityLevel=1.4'
+                cmd += ' -dQUIET'
+                cmd += ' -sDEVICE=pdfwrite'
+                cmd += ' "-sOutputFile={}"'.format(compressed_file)
                 cmd += ' "{}"'.format(original_file)
                 cmd += ' && '
                 cmd += 'mv "{}" "{}"'.format(compressed_file, original_file)
@@ -342,7 +350,8 @@ class OCRPipeline(WorkflowRunner):
                 lbl = 'pdf_compression_-_{}'.format(i)
                 pdf_compression_jobs.append(self.addTask(command=cmd,
                                                          dependencies=deps,
-                                                         label=lbl))
+                                                         label=lbl,
+                                                         nCores=n_cores))
 
         '''
         ' ##################################################