Fix thumbnail generation on Synology DSM and File Station for HEIC photos and HVEC videos

Fix-synology-heic-hvec-thumbnails.md

Fix thumbnail generation on Synology DSM and File Station for HEIC photos and HVEC videos

Synology DiskStation DSM update 7.2.2 broke support for HEIC and video thumbnails such as HVEC.

This guide will help you setting up a scheduled task using filebot to generate the missing thumbnails in the background for File Station for the web and DS File on mobile.

Install packages

Log into DSM.

You first need to add third party package sources:

1. Package Center ► Settings ► Package Sources ► Add ► Name: FileBot and Location: https://get.filebot.net/syno/
2. Package Center ► Settings ► Package Sources ► Add ► Name: SynoCommunity and Location: https://packages.synocommunity.com/

Then, install the following packages:

1. Package Center ► Community ► Install Java Installer package
2. Package Center ► Community ► Install FileBot package
3. Package Center ► Community ► Install FFmpeg 7 package
4. Package Center ► Community ► Install ImageMagick package

Enable SSH access

For the rest of the process, you'll need to enable SSH access on your Synology NAS:

1. Control Panel ► Terminal & SNMP ► Terminal tab ► Check Enable SSH service, choose the port number you like (22) then click "Apply".

You can now connect to your Synology NAS using SSH as an administrator using the ssh your_username@synology_ip command on macOS and Linux or using any ssh client such as PuTTY on Windows.

Create the script

1. Make a scripts folder in your home folder.
2. Create the generate-photo-thumbnails.sh script file with the following content (replace the value of PHOTO_FOLDER by your photo folder if it's different):

#!/bin/bash

# Change this value with the location of your photo folder
PHOTO_FOLDER='/volume1/photo'

# Use flock to prevent multiple instances
LOCKFILE="/tmp/$(basename $0).lock"
exec 200>"$LOCKFILE"
flock -n 200 || {
    echo "Another instance of the script is already running."
    exit 0
}

# Use the folder provided as argument. Otherwise, use PHOTO_FOLDER.
FOLDER_PATH="${1:-$PHOTO_FOLDER}"

echo "Generating thumbnails for ${FOLDER_PATH}"

# Generate HEIC photos thumbnails
filebot -find "$FOLDER_PATH" --filter 'def i = f.dir / "@eaDir" / f.name / "SYNOFILE_THUMB_M.jpg"; ext ==~ /(?i:HEIC|HEIF)/ && !i.exists() && (i.dir.exists() || i.dir.mkdirs())' \
    -exec /usr/local/bin/magick '{f}' -thumbnail '360x448>' -write '{folder}/@eaDir/{f.name}/SYNOFILE_THUMB_M.jpg' -thumbnail '120x160>' '{folder}/@eaDir/{f.name}/SYNOFILE_THUMB_S.jpg'

# Generate video thumbnails
filebot -find "$FOLDER_PATH" --filter 'def i = f.dir / "@eaDir" / f.name / "SYNOVIDEO_VIDEO_SCREENSHOT.jpg"; f.video && (i.dir.exists() || i.dir.mkdirs()) && !i.exists() && seconds > 0' \
    -exec /usr/local/bin/ffmpeg7 -hide_banner -loglevel error -an -ss '{seconds/5}' -i '{f}' -vframes 1 -vf scale=size=hd480:force_original_aspect_ratio=decrease -f mjpeg -y '{folder}/@eaDir/{f.name}/SYNOVIDEO_VIDEO_SCREENSHOT.jpg'

Run the script

It's better to make sure the script actually works before adding it as a scheduled task.

You can run the script on a specific folder by typing the following command: bash ~/scripts/generate-photo-thumbnails.sh "/volume1/photo/some_pictures_folder"

The process may take several minutes and even hours depending on the amount of files you have to process.

You may also want to run the script on demand right after uploading a new folder.

Please be aware that the script is CPU intensive, it's why it's not possible to run several instances of the script at the same time.

If everything is fine (you should see the thumbnails in the folder in DSM) you proceed to the next step.

Create the scheduled task

1. Log into your Synology using SSH.
2. Go to your home folder by typing: cd ~
3. Get the full path of your home folder by typing pwd (you'll get something such as /var/services/homes/your_username).
4. Log into DSM.
5. Control Panel ► Task Scheduler ► Create ► Scheduled Task ► User defined-script.
6. Under the "General Settings" tab, set "Task" to Generate photo thumbnails and set "User" with your username.
7. Under the "Schedule" tab, check "Run on the following days" and set "Repeat" to "Daily". Under "Time", select a "Start time" somewhere in the middle of the night (ie 4am).
8. Under the "Task Settings" tab, set the "User-defined script" to bash /var/services/homes/your_username/scripts/generate-photo-thumbnails.sh (refer to the returned value at step 3).
9. Click "OK".

In the latest version - 7.2.2 just the SYNOVIDEO_VIDEO_SCREENSHOT.jpg did not work for me.

@vimaljoseph I found an issue where filebot fails if the video duration can't be determined. The workaround is to just skip the videos with no duration by adding seconds > 0 in the filter. This is a solution I found on Reddit.

The script was updated accordingly, you may want to give it a try as your issue may have the same root cause.

In addition, change your task settings to send the output log when it fails by email, it helps a lot for debugging.

Hi, I wanted to thank you, you helped me a lot. I also wanted to ask if there is a way to do it with .Webp

I also wanted to ask if there is a way to do it with .Webp

The problem here is that DSM fundamentally doesn't recognise *.webp as image files, so even if you create the SYNOPHOTO_* thumbnail files, File Station and friends won't request or display thumbnails.

I also wanted to ask if there is a way to do it with .Webp

The problem here is that DSM fundamentally doesn't recognise *.webp as image files, so even if you create the SYNOPHOTO_* thumbnail files, File Station and friends won't request or display thumbnails.

I can confirm. The script can be easily modified to include .webp files but the thumbnails remain invisible.

This does not work on DSM 7.2.3 with the latest iOS 26.
Thumbnails for new files are generated correctly with the script in the eaDir folder, but File Station still shows a generic icon instead of the preview.
For older HEIC files from 2024, DSM generates thumbnails properly when the folder is opened in File Station.
I also tried copying the contents of eaDir/old_file_with_correct_thumbnails.HEIC to eaDir/new_file_with_generic_icon.HEIC, but File Station continues to show a blank icon.
It looks like newer HEIC files are somehow not supported (or partially supported) by DSM or File Station.

For older HEIC files from 2024, DSM generates thumbnails properly when the folder is opened in File Station.

The thumbnails are generated in JPEG format using Imagemagick. You may need to update the Imagemagick package to the latest version to support iOS 26 HEIC files.

Yes., it's much easier to run with docker, scripts are from the forum:

sudo docker run --rm -e PUID=0 -e PGID=0 -v 'data:/data' -v "/volume1:/volume1" rednoah/filebot \
	-find "/volume1/Media/Movies" --filter 'def i = f.dir / "@eaDir" / f.name / "SYNOVIDEO_VIDEO_SCREENSHOT.jpg"; f.video && !i.exists() && seconds > 0 && (i.dir.exists() || i.dir.mkdirs())' \
	-exec ffmpeg -an -ss '{seconds/5}' -i '{f}' -vframes 1 -vf scale=size=hd480:force_original_aspect_ratio=decrease -f mjpeg -y '{folder}/@eaDir/{f.name}/SYNOVIDEO_VIDEO_SCREENSHOT.jpg'

# or

SHARE='/volume1/Media'

docker run --rm -e PUID=0 -e PGID=0 -v 'data:/data' -v "$SHARE:$SHARE" rednoah/filebot \
	-find "$SHARE" --filter 'def i = f.dir / "@eaDir" / f.name / "SYNOVIDEO_VIDEO_SCREENSHOT.jpg"; f.video && !i.exists() && seconds > 0 && (i.dir.exists() || i.dir.mkdirs())' \
	-exec ffmpeg -an -ss '{seconds/5}' -i '{f}' -vframes 1 -vf scale=size=hd480:force_original_aspect_ratio=decrease -f mjpeg -y '{folder}/@eaDir/{f.name}/SYNOVIDEO_VIDEO_SCREENSHOT.jpg'

and for the photos:

SHARE='/volume1/Media'

docker run --rm -e PUID=0 -e PGID=0 -v 'data:/data' -v "$SHARE:$SHARE" rednoah/filebot \
	-find "$SHARE" --filter 'def i = f.dir / "@eaDir" / f.name / "SYNOFILE_THUMB_S.jpg"; ext ==~ /(?i:HEIC|HEIF)/ && !i.exists() && (i.dir.exists() || i.dir.mkdirs())' \
	-exec convert -verbose '{f}' -thumbnail '1280x1280>' -write '{folder}/@eaDir/{f.name}/SYNOFILE_THUMB_XL.jpg' -thumbnail '360x360>' -write '{folder}/@eaDir/{f.name}/SYNOFILE_THUMB_M.jpg' -thumbnail '120x120>' '{folder}/@eaDir/{f.name}/SYNOFILE_THUMB_S.jpg'