bundles/scansnap: do ocr in a separate process to speed up scanning

bundles/scansnap/files/ocr.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+set -euo pipefail
+
+DATE=$(date +%F_%H-%M-%S)
+
+cd "$1"
+
+convert *.tiff no_ocr.pdf
+ocrmypdf -l deu no_ocr.pdf has_ocr.pdf
+
+rm -f *.tiff
+rm -f no_ocr.pdf
+
+chown nobody:nogroup has_ocr.pdf
+
+mv has_ocr.pdf "/srv/scansnap/${DATE}.pdf"
+
+cd /
+
+rm -r "$1"

bundles/scansnap/files/scan.sh

@@ -2,17 +2,8 @@
 
 set -euo pipefail
 
-DATE=$(date +%F_%H-%M-%S)
-OUTFILE="/tmp/${DATE}"
+OUTFILE=$(mktemp -d)
 
-scanimage --source 'ADF Duplex' --format tiff --mode Gray --resolution 300 --page-width 210 --page-height 297.3 -x 210 -y 297.3 --batch=${OUTFILE}_p%04d.tiff
+scanimage --source 'ADF Duplex' --format tiff --mode Gray --resolution 300 --page-width 210 --page-height 297.3 -x 210 -y 297.3 --batch=${OUTFILE}/p%04d.tiff
 
-convert ${OUTFILE}_*.tiff ${OUTFILE}.pdf
-ocrmypdf -l deu ${OUTFILE}.pdf ${OUTFILE}.OCR.pdf
-
-rm -f ${OUTFILE}_*.tiff
-rm -f ${OUTFILE}.pdf
-
-chown nobody:nogroup "${OUTFILE}.OCR.pdf"
-
-mv "${OUTFILE}.OCR.pdf" "/srv/scansnap/${DATE}.pdf"
+/etc/scanbd/scripts/ocr.sh "$OUTFILE" &

bundles/scansnap/files/scanbd.conf

@@ -35,8 +35,8 @@ global {
         action scan {
                 filter = "^scan.*"
                 numerical-trigger {
-                        from-value = 1
-                        to-value   = 0
+                        from-value = 0
+                        to-value   = 1
                 }
                 desc   = "Scan to file"
                 script = "scan.sh"

bundles/scansnap/items.py

@@ -19,10 +19,17 @@ files = {
             'svc_systemd:scanbd:restart',
         },
     },
+    '/etc/scanbd/scripts/ocr.sh': {
+        'mode': '0755',
+        'needs': {
+            'directory:/srv/scansnap',
+        },
+    },
     '/etc/scanbd/scripts/scan.sh': {
         'mode': '0755',
         'needs': {
             'directory:/srv/scansnap',
+            'file:/etc/scanbd/scripts/ocr.sh',
         },
     },
 }