How do I make Shotwell regenerate all the thumbnails?

Question

For some unknown reason all thumbnails are lost in my Shotwell, instead all icons are grey. The images themselves are all okay and I can open them all in Shotwell.

There are only empty folders in .shotwell/thumbs/ so it looks like the thumbnails don't doesn't get generated at all.

I have also tried to re-install Shotwell (by purge it first) without any change.

score 15 · Accepted Answer · edited Jul 03 '14 at 11:54

This shell script will regenerate your thumbnails of sizes 128px and 360px so you'll see at least something in viewer.

sqlite3 ~/.local/share/shotwell/data/photo.db \
  "select id||' '||filename from PhotoTable order by timestamp desc" | 
  while read id filename; do
    for size in 128 360; do
      tf=$(printf ~/.cache/shotwell/thumbs/thumbs${size}/thumb%016x.jpg $id);
      test -e "$tf" ||  {
        echo -n "Generating thumb for $filename ($tf)";
        convert "$filename" -auto-orient -thumbnail ${size}x${size} $tf
        echo
      }
    done
  done

score 7 · Answer 2 · edited Apr 15 '13 at 20:40

An easy way for Shotwell to regenerate thumbnails (this is a workaround):

Go to your Photos page.
Edit -> Select All
Ctrl+R (rotate)
When finished rotating, Ctrl+Z (undo).

This will force Shotwell to regenerate all photos and honor any transformations it has stored for them.

As phq mentioned, there is an outstanding bug to fix this so you won't need this workaround. Until then, this is the recommended way to solve this problem. The script posted above will not honor transformations, meaning it's possible for your thumbnails to not look like your photos in Shotwell.

hultqvist · Answer 3 · 2015-01-31T08:48:33.280

5

Update With shotwell 0.18 thumbnails are now generated when manually viewed.

Don't remove .shotwell/thumbs!

According to this bug in launchpad, thumbnails are only generated on import.

Thumbnails are only generated at import. If the thumbnails are removed from disk they are not regenerated.

edited Jan 31 '15 at 08:48

answered Dec 01 '10 at 13:19

hultqvist

724

score 5 · Answer 4 · edited Apr 13 '17 at 12:23

I just used the shell script given in this answer, but I have about 22000 thumbnails to generate.

So here is a bash version of this script, using ~/.shotwell instead of ~/.local/shotwell (which is what I have) and using as many cores as my processor have (8 times faster in my case!):

#!/bin/bash

# under linux, use this to launch as many convert as your processor core number
#MAX_PROCESSES=`cat /proc/cpuinfo |grep ^processor | wc -l`
# or use a static value
MAX_PROCESSES=4

sqlite3 ~/.shotwell/data/photo.db "select id||' '||filename from PhotoTable order by timestamp desc" | 
  while read id filename; do
      for size in 128 360; do
      tf=$(printf ~/.shotwell/thumbs/thumbs${size}/thumb%016x.jpg $id);
      test -e "$tf" ||  {
              echo "Generating thumb for $filename ($tf)";
              convert "$filename" -auto-orient -thumbnail ${size}x${size} $tf &
          RUNNING="`jobs -p |wc -l`"
          while [ "$RUNNING" -ge "$MAX_PROCESSES" ]
          do
          sleep 0.3
          RUNNING="`jobs -p |wc -l`"
          done
      }
      done
  done

score 3 · Answer 5 · answered Apr 15 '13 at 19:35

3

Shotwell version 0.13.11 on Ubuntu 12.10 Thumbnails seem no longuer to be located in .shotwell/thumbs but now in .cache/shotwell You may check user has full rigths to read thumbs. Having access to pictures but not to thumbs may cause grey thumbs.

answered Apr 15 '13 at 19:35

Ludovic Cheron

31
1

score 2 · Answer 6 · answered Sep 02 '19 at 11:56

Shotwell 0.28.4 (Braunschweig) will sometimes not create video thumbnails. The following script derived from the accepted answer fixes this:

#!/bin/bash
declare -A default_thumbnail_sizes
declare -A default_thumbnail_checksums
default_thumbnail_sizes[128]="3038"
default_thumbnail_checksums[128]="dc292dd5c9eacadee4fa02c2062d364d8a3a42cb4a58b99abb42dd1950803e4d"
default_thumbnail_sizes[360]="12333"
default_thumbnail_checksums[360]="1f5859761cbbc44f7444b5a61ffd7b2dfe560017d8376905df67db51a4641926"

sqlite3 ~/.local/share/shotwell/data/photo.db \
  "select id||' '||filename from VideoTable" |
  while read id filename
  do
    for size in 128 360
    do
      tf=$(printf ~/.cache/shotwell/thumbs/thumbs${size}/video-%016x.jpg $id);
      exit_code="$?"
      if [[ "$exit_code" != "0" ]]
      then
        echo $id
        continue
      fi

      if [[ -e "$tf" ]]
      then
        tfilelength=$(stat -c '%s' $tf)
        if [[ "$tfilelength" != ${default_thumbnail_sizes[$size]} ]]
        then
          continue
        fi

        tchecksum=$(sha256sum $tf)
        if [[ "$tchecksum" != ${default_thumbnail_checksums[$size]}* ]]
        then
          continue
        fi
      fi

      echo -n "$filename --> $tf";
      ttf=/tmp/$(basename "$tf")
      rm -f "$ttf"
      ffmpeg -i "$filename" -loglevel quiet -vf "thumbnail,scale=${size}:-1" -frames:v 1 "$ttf"
      exit_code="$?"
      if [[ -e "$ttf" && $exit_code == "0" ]]
      then
        echo ": SUCCESS"
        mv -f -v "$ttf" "$tf"
        echo
      else
        echo ": FAILED ($exit_code)"
        echo
      fi
    done
  done

score 2 · Answer 7 · answered Nov 23 '17 at 20:36

2

For version 0.26.3 (up-to-date as of Nov. 2017), with Shotwell closed, just delete the thumbnails in

/home/user_name/.cache/shotwell/thumbs/thumbs128 and in
/home/user_name/.cache/shotwell/thumbs/thumbs360

and fire up Shotwell, again.

answered Nov 23 '17 at 20:36

nutty about natty

6,978

How do I make Shotwell regenerate all the thumbnails?

7 Answers7