# Previews / data size **URL:** \ **Category:** ℹ️ Support\ **Tags:** previewgenerator-app\ **Created:** [February 6, 2019, 9:09am UTC](https://help.nextcloud.com/t/previews-data-size/46990 "2019-02-06T09:09:45Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![s25a](https://help.nextcloud.com/letter_avatar/s25a/32/6_22734026db12803ebb3e059622ac3534.png) [@s25a](https://help.nextcloud.com/u/s25a)\ **Post date:** [February 6, 2019, 9:09am UTC](https://help.nextcloud.com/t/previews-data-size/46990/1 "2019-02-06T09:09:45Z")
Hi, I have installed this extension to have a much quicker preview for my pictures on my ios devices. I started the process and it took days and suddenly stopped. NExtcloud was not reachable. So what happened is that in the nextcloud/data/preview folder there have been thousand of sub folders with a size of more than 50GB, That stopped NC working because no more space left. I have a lot of pictures however I am not sure if I really need that amount of previews. Can someone help to find the right process to setup only the previews pictures for the nexcloud APP on IOS? Or do I really need all? Thanks S ---
**Author:** ![gas85](https://help.nextcloud.com/user_avatar/help.nextcloud.com/gas85/32/7772_2.png) [@gas85](https://help.nextcloud.com/u/gas85)\ **Post date:** [February 6, 2019, 11:06am UTC](https://help.nextcloud.com/t/previews-data-size/46990/2 "2019-02-06T11:06:46Z")
Fist of all you have to adjust what kind of previews you would like to have. I have had the same problem and have to setup my config.php as following to have only FullHD previews maximal (default is 4096): ``` 'enable_previews' => true, 'enabledPreviewProviders' => array ( 0 => 'OC\\Preview\\PNG', 1 => 'OC\\Preview\\JPEG', 2 => 'OC\\Preview\\GIF', 3 => 'OC\\Preview\\BMP', 4 => 'OC\\Preview\\XBitmap', 5 => 'OC\\Preview\\Movie', 6 => 'OC\\Preview\\PDF', 7 => 'OC\\Preview\\MP3', 8 => 'OC\\Preview\\TXT', 9 => 'OC\\Preview\\MarkDown', ), 'preview_max_x' => 1080, 'preview_max_y' => 1920, ``` More about previews config is here: [https://docs.nextcloud.com/server/latest/admin\_manual/configuration\_server/config\_sample\_php\_parameters.html#previews](https://docs.nextcloud.com/server/latest/admin_manual/configuration_server/config_sample_php_parameters.html#previews) After you change those settings you need to delete all files in preview folder and perform some DB cleanup and generate new previews. Here I open a ticket regarding documentation and solutions are listed there: > > > Hello, > by surfing in tickets I seen one new for me command - occ files:scan-app-data, unfortunately it is documented nowhere. > Regards! I wrote small script to put previews generation status into my NC Logs: [How to know if Preview Generator is working?](https://help.nextcloud.com/t/how-to-know-if-preview-generator-is-working/41072/6) ---
**Author:** ![s25a](https://help.nextcloud.com/letter_avatar/s25a/32/6_22734026db12803ebb3e059622ac3534.png) [@s25a](https://help.nextcloud.com/u/s25a)\ **Post date:** [February 6, 2019, 1:58pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/3 "2019-02-06T13:58:11Z")
Hi, thanks a lot. I added the config you provided above into my config.php in the nextcloud folder restarted php and apache and deleted all files in the Preview Foler. Than excecuted: `sudo -u www-data php occ preview:delete_old` Then restarted the process with `sudo -u www-data php occ preview:generate-all` It starts to generate again the folder unders Preview. In each folder there is the preview of one image…See screenshot. ![4](https://help.nextcloud.com/uploads/default/original/2X/3/3ad2a5b82755a9ee0f330603addff13754e7c2ef.jpeg) For what reason do I nee all those files? I just want to have a quick view in my IOS App. Thanks S And by the way it still generates much bigger files than in the config defined: ``` '***', 'passwordsalt' => '**', 'secret' => ***', 'trusted_domains' => array ( 0 => 'nextcloud. ****', ), 'datadirectory' => '/var/www/html/nextcloud/data', 'dbtype' => 'mysql', 'version' => '15.0.2.0', 'overwrite.cli.url' => ' *****', 'dbname' => 'nextcloud', 'dbhost' => 'localhost:3306', 'dbport' => '', 'dbtableprefix' => 'oc_', 'dbuser' => 'nextcloud', 'dbpassword' => '***', 'installed' => true, 'memcache.distributed' => '\\OC\\Memcache\\Redis', 'memcache.locking' => '\\OC\\Memcache\\Redis', 'memcache.local' => '\\OC\\Memcache\\APCu', 'redis' => array ( 'host' => '127.0.0.1', 'port' => 6379, 'enable_previews' => true, 'enabledPreviewProviders' => array ( 0 => 'OC\\Preview\\PNG', 1 => 'OC\\Preview\\JPEG', 2 => 'OC\\Preview\\GIF', 3 => 'OC\\Preview\\BMP', 4 => 'OC\\Preview\\XBitmap', 5 => 'OC\\Preview\\Movie', 6 => 'OC\\Preview\\PDF', 7 => 'OC\\Preview\\MP3', 8 => 'OC\\Preview\\TXT', 9 => 'OC\\Preview\\MarkDown', ), 'preview_max_x' => 1080, 'preview_max_y' => 1920, ), ); ``` ---
**Author:** ![gas85](https://help.nextcloud.com/user_avatar/help.nextcloud.com/gas85/32/7772_2.png) [@gas85](https://help.nextcloud.com/u/gas85)\ **Post date:** [February 6, 2019, 2:27pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/4 "2019-02-06T14:27:47Z")
Basically you will have a lot of numbered sub folders in `preview`, each folder will contains few smaller previews of **one picture** in a **different size**. This will give you quicker pre generated previews in web and Client. > [@s25a](#): > > And by the way it still generates much bigger files than in the config defined: On your screenshot bigger file is marked as 753x511-max, so it is not even 1920x1080. Or what you means? ---
**Author:** ![s25a](https://help.nextcloud.com/letter_avatar/s25a/32/6_22734026db12803ebb3e059622ac3534.png) [@s25a](https://help.nextcloud.com/u/s25a)\ **Post date:** [February 6, 2019, 2:43pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/5 "2019-02-06T14:43:11Z")
Hi, thanks a lot for your quick answer. Yes that example was not good as the picture itself is below 1920_1080. For the high Res pictures it’s still 4096_ Maybe any mistake in the config? I used the config.php in the config folder. Thanks S ---
**Author:** ![gas85](https://help.nextcloud.com/user_avatar/help.nextcloud.com/gas85/32/7772_2.png) [@gas85](https://help.nextcloud.com/u/gas85)\ **Post date:** [February 6, 2019, 2:51pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/6 "2019-02-06T14:51:56Z")
> [@s25a](#): > > I used the config.php in the config folder. This is correct one > [@s25a](#): > > ``` > 'preview_max_x' => 1080, > 'preview_max_y' => 1920, > > ``` > > ), > ); Have you delete something here? Because it is one `),` too much at the end. ---
**Author:** ![s25a](https://help.nextcloud.com/letter_avatar/s25a/32/6_22734026db12803ebb3e059622ac3534.png) [@s25a](https://help.nextcloud.com/u/s25a)\ **Post date:** [February 6, 2019, 5:02pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/7 "2019-02-06T17:02:18Z")
Hi, > Have you delete something here? Because it is one `),` too much at the end No I have deleted nothing but added the config in the wrong place. After the ,(komma) not before and now it seems doing it in the right way. Thanks I have also executed these commands to limit the number of previews. ```auto ./occ config:app:set --value="32 64 1024" previewgenerator squareSizes ./occ config:app:set --value="64 128 1024" previewgenerator widthSizes ./occ config:app:set --value="64 256 1024" previewgenerator heightSizes ``` But this did change anything Thanks S ---
**Author:** ![wwe](https://help.nextcloud.com/user_avatar/help.nextcloud.com/wwe/32/72963_2.png) [@wwe](https://help.nextcloud.com/u/wwe)\ **Post date:** [December 4, 2024, 9:16am UTC](https://help.nextcloud.com/t/previews-data-size/46990/8 "2024-12-04T09:16:19Z")
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**Author:** ![wwe](https://help.nextcloud.com/user_avatar/help.nextcloud.com/wwe/32/72963_2.png) [@wwe](https://help.nextcloud.com/u/wwe)\ **Post date:** [December 11, 2024, 2:23pm UTC](https://help.nextcloud.com/t/previews-data-size/46990/9 "2024-12-11T14:23:40Z")