Image renditions not created when uploading a PNG image into DAM - CommonsGfxRenderer gfx: cannot get image for rendition

[#1]

AEM 6.4 (Service Pack 8 (6.4.8.0)) fails to create image renditions for PNG and GIF files, other file types work as expected. This usually works, but out of the blue we see following WARN messages in error.log while uploading a PNG file:

05.01.2021 09:50:56.972 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.adobe.xmp.worker.files.ncomm.XMPFilesNComm [PERF][EXECUTE_START] | /content/crx/tmp/cq-dam-wf-file6534904148032421539.tmp | XMP extraction
05.01.2021 09:50:56.972 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.adobe.xmp.worker.files.ncomm.XMPFilesNComm [XMPFilesProcessor-19349] PROC: Executing request extractXMP
05.01.2021 09:50:56.972 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.adobe.xmp.worker.files.ncomm.XMPFilesNComm [PERF][EXECUTE_END] | /content/crx/tmp/cq-dam-wf-file6534904148032421539.tmp | XMP extraction
05.01.2021 09:50:56.972 *WARN* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.impl.handler.GenericAssetHandler Using FormatHandlers for extracting metadata
05.01.2021 09:50:56.978 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.adobe.granite.asset.core.impl.metadata.xmpjcr.XmpToJcrVisitor No custom schema available, using default XMP schema service
05.01.2021 09:50:56.988 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.video.FFMpegThumbnailProcess execute: asset [/content/dam/test03.png] is not of a video mime type, asset ignored.
05.01.2021 09:50:56.989 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.process.CommandLineProcess execute: mime type [image/png] of asset [/content/dam/test03.png] is not in list of accepted mime types [[image/eps, image/x-eps, application/postscript, application/eps, application/x-eps]], ignoring.
05.01.2021 09:50:56.990 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.video.FFMpegTranscodeProcess execute: asset [/content/dam/test03.png] is not of a video mime type, asset ignored.
05.01.2021 09:50:56.997 *WARN* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.impl.gfx.CommonsGfxRenderer gfx: cannot get image for rendition: /content/dam/test03.png/jcr:content/renditions/original
05.01.2021 09:50:56.999 *WARN* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.impl.gfx.CommonsGfxRenderer gfx: cannot get image for rendition: /content/dam/test03.png/jcr:content/renditions/original
05.01.2021 09:50:57.001 *WARN* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.impl.gfx.CommonsGfxRenderer gfx: cannot get image for rendition: /content/dam/test03.png/jcr:content/renditions/original
05.01.2021 09:50:57.007 *WARN* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.core.impl.gfx.CommonsGfxRenderer gfx: cannot get image for rendition: /content/dam/test03.png/jcr:content/renditions/original
05.01.2021 09:50:57.010 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.pim.impl.sourcing.upload.process.ProductAssetsUploadProcess payload path :/content/dam/test03.png/jcr:content/renditions/original
05.01.2021 09:50:57.015 *INFO* [JobHandler: /var/workflow/instances/server0/2021-01-02/update_asset_27:/content/dam/test03.png/jcr:content/renditions/original] com.day.cq.dam.scene7.impl.process.AbstractScene7UploadProcess Skip S7 upload due to cannot find configuration for file: /content/dam/test03.png

We're able to fix the issue temporarily by restarting Day Communique 5 DAM Core Implementation (com.day.cq.dam.cq-dam-core) bundle, however it gets broken after few days again.

[#2 · Accepted solution]

That's a strange behavior, because restarting a bundle should not change any internal state.

The only thing I could imagine for this is that a service is stopped from that bundle during these days.

Before you restart that bundle, can you check the list of services exported from that bundle and their state and compare it the same after you have restarted the bundle?