diff --git a/README.md b/README.md
index abc6bfc..a54bc0a 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ using multiple cores is supported.
 ## Usage ##
 
 ```
-Usage: $0 [-adhrsvzZ] imagefile.img [newimagefile.img]
+Usage: $0 [-adhrsvzZn] imagefile.img [newimagefile.img]
 
   -s         Don't expand filesystem when image is booted the first time
   -v         Be verbose
@@ -17,6 +17,7 @@ Usage: $0 [-adhrsvzZ] imagefile.img [newimagefile.img]
   -Z         Compress image after shrinking with xz
   -a         Compress image in parallel using multiple cores
   -d         Write debug messages in a debug log file
+  -n         Accept an input that is not a file (e.g. a tf card)
 ```
 
 If you specify the `newimagefile.img` parameter, the script will make a copy of `imagefile.img` and work off that. You will need enough space to make a full copy of the image to use that option.
@@ -28,6 +29,7 @@ If you specify the `newimagefile.img` parameter, the script will make a copy of
 * `-Z` will compress the image after shrinking using xz. `.xz` extension will be added to the filename.
 * `-a` will use option -f9 for pigz and option -T0 for xz and compress in parallel.
 * `-d` will create a logfile `pishrink.log` which may help for problem analysis.
+* `-n` will shrink the file system of a tfcard, and create an image file from that if `newimagefile.img` is specified.
 
 Default options for compressors can be overwritten by defining PISHRINK_GZIP or PSHRINK_XZ environment variables for gzip and xz.
 
@@ -48,10 +50,10 @@ chmod +x pishrink.sh
 sudo mv pishrink.sh /usr/local/bin
 ```
 
-## Example ##
+## Example 1 ##
 
 ```bash
-[user@localhost PiShrink]$ sudo pishrink.sh pi.img
+sudo pishrink.sh pi.img
 e2fsck 1.42.9 (28-Dec-2013)
 Pass 1: Checking inodes, blocks, and sizes
 Pass 2: Checking directory structure
@@ -73,6 +75,28 @@ The filesystem on /dev/loop1 is now 773603 blocks long.
 Shrunk pi.img from 30G to 3.1G
 ```
 
+## Example 2 ##
+
+```bash
+sudo pishrink.sh -n /dev/sdb pi.img
+pishrink.sh v0.1.3
+pishrink.sh: Gathering data ...
+
+pishrink.sh: Checking filesystem ...
+rootfs: 69602/155648 files (0.4% non-contiguous), 457517/599771 blocks
+resize2fs 1.46.5 (30-Dec-2021)
+pishrink.sh: Shrinking filesystem ...
+resize2fs 1.46.5 (30-Dec-2021)
+Resizing the filesystem on /dev/sdb2 to 597213 (4k) blocks.
+The filesystem on /dev/sdb2 is now 597213 (4k) blocks long.
+
+pishrink.sh: Creating image ...
+5310185+0 records in
+5310185+0 records out
+2718814720 bytes (2.7 GB, 2.5 GiB) copied, 294.339 s, 9.2 MB/s
+pishrink.sh: Shrunk pi.img from 8, to 2.6G ...
+```
+
 ## Contributing ##
 
 If you find a bug please create an issue for it. If you would like a new feature added, you can create an issue for it but I can't promise that I will get to it.
diff --git a/pishrink.sh b/pishrink.sh
index f16af49..4699b62 100755
--- a/pishrink.sh
+++ b/pishrink.sh
@@ -165,7 +165,7 @@ EOF1
 help() {
 	local help
 	read -r -d '' help << EOM
-Usage: $0 [-adhrsvzZ] imagefile.img [newimagefile.img]
+Usage: $0 [-adhrsvzZn] imagefile.img [newimagefile.img]
 
   -s         Don't expand filesystem when image is booted the first time
   -v         Be verbose
@@ -174,6 +174,7 @@ Usage: $0 [-adhrsvzZ] imagefile.img [newimagefile.img]
   -Z         Compress image after shrinking with xz
   -a         Compress image in parallel using multiple cores
   -d         Write debug messages in a debug log file
+  -n         Accept an input that is not a file (e.g. a tf card)
 EOM
 	echo "$help"
 	exit 1
@@ -185,8 +186,9 @@ repair=false
 parallel=false
 verbose=false
 ziptool=""
+notfile=false
 
-while getopts ":adhrsvzZ" opt; do
+while getopts ":adhrsvzZn" opt; do
   case "${opt}" in
     a) parallel=true;;
     d) debug=true;;
@@ -196,6 +198,7 @@ while getopts ":adhrsvzZ" opt; do
     v) verbose=true;;
     z) ziptool="gzip";;
     Z) ziptool="xz";;
+    n) notfile=true;;
     *) help;;
   esac
 done
@@ -219,10 +222,14 @@ if [[ -z "$img" ]]; then
   help
 fi
 
-if [[ ! -f "$img" ]]; then
-  error $LINENO "$img is not a file..."
-  exit 2
+if [ "$notfile" = false ]; then
+  echo "$notfile"
+  if [[ ! -f "$img" ]]; then
+    error $LINENO "$img is not a file..."
+    exit 2
+  fi
 fi
+
 if (( EUID != 0 )); then
   error $LINENO "You need to be running as root."
   exit 3
@@ -261,19 +268,21 @@ done
 
 #Copy to new file if requested
 if [ -n "$2" ]; then
-  f="$2"
-  if [[ -n $ziptool && "${f##*.}" == "${ZIPEXTENSIONS[$ziptool]}" ]]; then	# remove zip extension if zip requested because zip tool will complain about extension
-    f="${f%.*}"
-  fi
-  info "Copying $1 to $f..."
-  cp --reflink=auto --sparse=always "$1" "$f"
-  if (( $? != 0 )); then
-    error $LINENO "Could not copy file..."
-    exit 5
-  fi
-  old_owner=$(stat -c %u:%g "$1")
-  chown "$old_owner" "$f"
-  img="$f"
+  if [ "$notfile" = false ]; then #Skip copy if input is device
+    f="$2"
+    if [[ -n $ziptool && "${f##*.}" == "${ZIPEXTENSIONS[$ziptool]}" ]]; then	# remove zip extension if zip requested because zip tool will complain about extension
+      f="${f%.*}"
+    fi
+    info "Copying $1 to $f..."
+    cp --reflink=auto --sparse=always "$1" "$f"
+    if (( $? != 0 )); then
+      error $LINENO "Could not copy file..."
+      exit 5
+    fi
+    old_owner=$(stat -c %u:%g "$1")
+    chown "$old_owner" "$f"
+    img="$f"
+  fi  
 fi
 
 # cleanup at script exit
@@ -292,17 +301,21 @@ fi
 partnum="$(echo "$parted_output" | tail -n 1 | cut -d ':' -f 1)"
 partstart="$(echo "$parted_output" | tail -n 1 | cut -d ':' -f 2 | tr -d 'B')"
 if [ -z "$(parted -s "$img" unit B print | grep "$partstart" | grep logical)" ]; then
-    parttype="primary"
+  parttype="primary"
 else
-    parttype="logical"
+  parttype="logical"
+fi
+if [ "$notfile" = false ]; then
+  loopback="$(losetup -f --show -o "$partstart" "$img")"
+else
+  loopback=""$img""2""
 fi
-loopback="$(losetup -f --show -o "$partstart" "$img")"
 tune2fs_output="$(tune2fs -l "$loopback")"
 rc=$?
 if (( $rc )); then
-    echo "$tune2fs_output"
-    error $LINENO "tune2fs failed. Unable to shrink this type of image"
-    exit 7
+  echo "$tune2fs_output"
+  error $LINENO "tune2fs failed. Unable to shrink this type of image"
+  exit 7
 fi
 
 currentsize="$(echo "$tune2fs_output" | grep '^Block count:' | tr -d ' ' | cut -d ':' -f 2)"
@@ -378,21 +391,37 @@ if (( $rc )); then
 fi
 
 #Truncate the file
-info "Shrinking image"
-endresult=$(parted -ms "$img" unit B print free)
-rc=$?
-if (( $rc )); then
-	error $LINENO "parted failed with rc $rc"
-	exit 15
-fi
+if [ "$notfile" = false ]; then 
+  info "Shrinking image"
+  endresult=$(parted -ms "$img" unit B print free)
+  rc=$?
+  if (( $rc )); then
+    error $LINENO "parted failed with rc $rc"
+    exit 15
+  fi
 
-endresult=$(tail -1 <<< "$endresult" | cut -d ':' -f 2 | tr -d 'B')
-logVariables $LINENO endresult
-truncate -s "$endresult" "$img"
-rc=$?
-if (( $rc )); then
-	error $LINENO "trunate failed with rc $rc"
-	exit 16
+  endresult=$(tail -1 <<< "$endresult" | cut -d ':' -f 2 | tr -d 'B')
+  logVariables $LINENO endresult
+  truncate -s "$endresult" "$img"
+  rc=$?
+  if (( $rc )); then
+    error $LINENO "trunate failed with rc $rc"
+    exit 16
+  fi
+else #Skip truncate if input is device
+  if [ -n "$2" ]; then
+    target="$2"
+    info "Creating image"
+    fdiskresult=$(fdisk -l "$img")
+    count=$(tail -1 <<< "$fdiskresult" | tr -s ' ' | cut -d ' ' -f 3)
+    bs=$(head -3 <<< "$fdiskresult" | tail -1 | tr -s ' ' | rev | cut -d ' ' -f 2 | rev)
+    count=$(expr "$count" + 1)
+    dd if="$img" of="$target" bs="$bs" count="$count"
+    img="$target"
+  else
+    info "File system shrinked from $beforesize to $aftersize, no image created"
+    exit 0
+  fi
 fi
 
 # handle compression