From d33c8caa713e45361af66bc96a86f32cce15b3a5 Mon Sep 17 00:00:00 2001
From: Raman Gupta <rocketraman@gmail.com>
Date: Wed, 10 Mar 2021 22:07:03 -0500
Subject: [PATCH] performance: pnmtops to temp file

For some reason when piping the output of pnmtops directly to ps2pdf,
conversion is very slow (especially for color scans).

When writing to an intermediate temporary file, conversion is fast.

Before:

________________________________________________________
Executed in   19.20 secs   fish           external
  usr time    4.01 secs    0.32 millis    4.01 secs
  sys time   20.63 secs    5.30 millis   20.62 secs

After:

________________________________________________________
Executed in  368.06 millis    fish           external
   usr time  378.06 millis    0.00 millis  378.06 millis
   sys time  100.00 millis    2.79 millis   97.21 millis

An improvement of over 50 times!

This should resolve #19.
---
 scan_perpage | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/scan_perpage b/scan_perpage
index f7adfdf..a1793a5 100755
--- a/scan_perpage
+++ b/scan_perpage
@@ -59,6 +59,11 @@ IMAGE_PATH=$1
 IMAGE_DIR=$(dirname $1)
 IMAGE_FILE=$(basename $1)
 
+TIMEVERBOSE=
+if [[ $VERBOSE == 1 ]]; then
+  TIMEVERBOSE=time
+fi
+
 process_page() {
   log ""
   log "-------------------------------------------------------------------------------"
@@ -80,14 +85,16 @@ process_page() {
       if [[ $VERBOSE == 1 ]]; then
         UNPAPERVERBOSE="-v"
       fi
-      #runconstrained unpaper $UNPAPERVERBOSE --no-mask-scan --overwrite --dpi $RESOLUTION --no-blackfilter $IMAGE_FILE $PP_PREFIX$IMAGE_FILE | logstdout
-      runconstrained unpaper $UNPAPERVERBOSE --overwrite --dpi $RESOLUTION $IMAGE_PATH $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE | logstdout
+      #runconstrained $TIMEVERBOSE unpaper $UNPAPERVERBOSE --no-mask-scan --overwrite --dpi $RESOLUTION --no-blackfilter $IMAGE_FILE $PP_PREFIX$IMAGE_FILE | logstdout
+      runconstrained $TIMEVERBOSE unpaper $UNPAPERVERBOSE --overwrite --dpi $RESOLUTION $IMAGE_PATH $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE | logstdout
     fi
     if [[ $SEARCHABLE == 1 ]]; then
       log "Converting image data to searchable pdf..."
       # tesseract uses the input's DPI header, we need to convert to a format that supports this (like tiff)
-      runconstrained convert -density ${RESOLUTION}x${RESOLUTION} -units PixelsPerInch $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff | logstdout
-      runconstrained tesseract $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff $IMAGE_DIR/${IMAGE_FILE%.*} -l $LANGUAGE pdf | logstdout
+      log "...Running convert"
+      runconstrained $TIMEVERBOSE convert -density ${RESOLUTION}x${RESOLUTION} -units PixelsPerInch $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff | logstdout
+      log "...Running tesseract"
+      runconstrained $TIMEVERBOSE tesseract $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff $IMAGE_DIR/${IMAGE_FILE%.*} -l $LANGUAGE pdf | logstdout
       [[ -f $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff ]] && rm $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.tiff
     else
       log "Converting image data to pdf..."
@@ -101,9 +108,11 @@ process_page() {
       if [[ $VERBOSE = 1 && ! "$(pnmtops -verbose 2>&1 < /dev/null)" =~ "unrecognized option" ]]; then
         PNMVERBOSE="-verbose"
       fi
-      log "Using page options: $PAGEOPTS"
-      runconstrained pnmtops $PNMVERBOSE $PAGEOPTS $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE | ps2pdf $PS2PDF_OPTS - > $IMAGE_DIR/${IMAGE_FILE%.*}.pdf | logstdout
-      [[ -f $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.ps ]] && rm $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.ps
+      log "...Running pnmtops on $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE using page options: $PAGEOPTS"
+      runconstrained $TIMEVERBOSE pnmtops $PNMVERBOSE $PAGEOPTS $IMAGE_DIR/$PP_PREFIX$IMAGE_FILE > $IMAGE_DIR/${IMAGE_FILE}.ps | logstdout
+      log "...Running ps2pdf on $IMAGE_DIR/${IMAGE_FILE}.ps"
+      runconstrained $TIMEVERBOSE ps2pdf $PS2PDF_OPTS $IMAGE_DIR/${IMAGE_FILE}.ps $IMAGE_DIR/${IMAGE_FILE}.pdf | logstdout
+      [[ -f $IMAGE_DIR/${IMAGE_FILE}.ps ]] && rm $IMAGE_DIR/$PP_PREFIX${IMAGE_FILE}.ps
     fi    
   else
     log "Skipping empty page $IMAGE_FILE with white percentage $PERCENTAGE_WHITE"