Fixed problems when passing true or false options to the convert function. Increased default contrast, useful in the Gray mode when the Lineart mode fails. Updated the readme.

README.md

@@ -13,7 +13,7 @@ will be automatically appended to the tail of the file.
   with a resolution of 600 DPI, using Unpaper and with image enhancing options 
   on the output file `out.pdf`
 
-      ./specrescan out.pdf
+        ./specrescan out.pdf
 
 - Same as before but for double sided paper
 
@@ -22,7 +22,27 @@ will be automatically appended to the tail of the file.
 - Scan in colour, with a resolution of 300 DPI, using the flatbed,
   on the output file `out.pdf`
 
-      ./spectrscan -m Color -r 300 -s Flatbed out.pdf
+        ./spectrscan -m Color -r 300 -s Flatbed out.pdf
+
+- Disable unpaper (same procedure for imagemagick):
+
+        ./spectrscan -ufalse out.pdf
+        ./spectrscan --unpaper_options=false out.pdf
+
+If the scanned text results unreadable try using the `Gray` mode instead
+of the default `Lineart`.
+
+Currently, passing options to unpaper and imagemagick is not working. You 
+should edit the options directly in the script. By default, contrast is set at 
+a very high level. You can edit
+
+    imagemagick_options="-normalize -level 70%,100%,1.0"
+
+with something like:
+
+    imagemagick_options="-normalize -level 20%,100%,1.0"
+
+and see what happens.
 
 ## Path
 
@@ -106,6 +126,8 @@ http://www.jduck.net/blog/2008/01/05/ocr-scanning/
 
 https://www.ubuntu-user.com/Magazine/Archive/2013/18/Scanning-and-editing-text-with-OCR
 
+http://www.jpeek.com/articles/linuxmag/2006-08/
+
 ## Dependencies and explanations
 
 - [GNU Bash](http://www.gnu.org/software/bash/bash.html)

spectrscan

@@ -24,7 +24,7 @@
 tmp_dir="$(pwd)/.spectrscan-$RANDOM"
 src_dir="$(pwd)"
 
-imagemagick_options="-contrast-stretch 0.5%x10% -compress lzw"
+imagemagick_options="-normalize -level 70%,100%,1.0"
 mode="Lineart"
 resolution="600"
 source="ADF"
@@ -144,30 +144,35 @@ exists_output_file()
 
 convert_single()
 {
+    # First convert to pdf with the image enhancements, then apply unpaper.
+    # This giuves better results because it avoids missing information in
+    # the finakl result.
     local filE="$1"
 
-    pamfix -truncate "$filE" > "$filE".tmp.pnm
+    pamfix -truncate "$filE" > "$filE".tmp.pnm.bis
 
-    if [ "$unpaper_options" = "true" ]; then
-        unpaper --overwrite -q "$filE".tmp.pnm "$filE"
-    elif [ "$unpaper_options" = "false" ]; then
-        mv "$filE".tmp.pnm "$filE"
+    if [ "$imagemagick_options" != "true" ] \
+        && [ "$imagemagick_options" != "false" ]; then
+        convert $imagemagick_options "$filE".tmp.pnm.bis "$filE".tmp.pnm
     else
-        unpaper --overwrite -q $unpaper_options "$filE".tmp.pnm "$filE"
+        mv "$filE".tmp.pnm.bis "$filE".tmp.pnm
     fi
 
     # OCR stuff goes here.
 
+    printf "\n UNPAPER = $unpaper_options \n"
 
-    if [ "$imagemagick_options" = "true" ]; then
-        convert "$filE" "$filE".pdf
-    elif [ "$imagemagick_options" = "false" ]; then
-        convert "$filE" "$filE".pdf
+    if [ "$unpaper_options" = "true" ]; then
+        unpaper --overwrite -q "$filE".tmp.pnm "$filE".pnm
+    elif [ "$unpaper_options" = "false" ]; then
+        mv "$filE".tmp.pnm "$filE".pnm
     else
-        # Contrast enhancement and pdf.
-        convert $imagemagick_options "$filE" "$filE".pdf
+        unpaper --overwrite -q $unpaper_options "$filE".tmp.pnm "$filE".pnm
     fi
-} 1>/dev/null 2>/dev/null
+
+    convert -compress lzw "$filE".pnm "$filE".pdf
+
+} #1>/dev/null 2>/dev/null
 
 pnm_to_pdf()
 {
@@ -178,6 +183,8 @@ pnm_to_pdf()
     # n = number of new pages
     # Time complexity: O(n/#cores)
     export -f convert_single
+    export unpaper_options
+    export imagemagick_options
     parallel --bar convert_single ::: "$(ls spectrscan_*.pnm)"
 }
 
@@ -212,7 +219,7 @@ pdf_cat()
 cleanup()
 {
     popd
-    rm -rf "$tmp_dir" 
+    rm -rf "$tmp_dir"
 } 1>/dev/null 2>/dev/null
 
 chain()
@@ -293,8 +300,10 @@ source:,unpaper-options::"
     while true ; do
         case "$1" in
             -h | --help )           shift; help; return 2                   ;;
-            -i | --imagemagick-options ) \
-                                    imagemagick_options="$2"; shift 2       ;;
+            -i | --imagemagick-options )
+                case "$2" in
+                    * )             imagemagick_options="$2"; shift 2       ;;
+                esac ;;
             -m | --mode )
                 case "$2" in
                     "" )            getopt_error && return 1                ;;
@@ -320,7 +329,7 @@ source:,unpaper-options::"
                     * )             source="$2"; shift 2                    ;;
                 esac ;;
             --list-sources )        shift; get_supported_sources; return 2  ;;
-            -u | --unpaper-options ) \
+            -u | --unpaper-options )
                                     unpaper_options="$2"; shift 2           ;;
             -- )                    shift; break                            ;;
             * )                     return 1                                ;;