Artwork not showing

[paulr]

Hi, I have a library of flac files on a NAS and Minimserver 2.2 running ok on there.
I have a NAIM streamer with it's own control point app and served by Minimserver.
I also have a Bluesound box which has it's own way of indexing the content etc (i.e. it does not use Minim).
I use JRiver on my pc which also has it's own database.
Artwork is embedded in each music file, there be the odd missing one, some albums may have a jpeg file present in the album folder.
My problem is that the Naim app has suddenly stopped displaying upwards of 90% of the album artwork and I'm trying to troubleshoot this. I cant find anyone else in the Naim community with this happening i.e. I don't think its the Naim app, I don't believe there is a general minim problem, but that something has happened on my setup.
Both the Bluesound and Jriver apps show the artwork ok.
The artwork has not changed, not on 70000 files anyway, my minimserver settings have not changed.
Also I’ve noticed, while troubleshooting, the ‘recently added’ contains only stuff from a month or so ago, it should be much more than this. Both Jriver and Bluesounds’ recent views hold much more stuff i.e. more like what I’d expect.
I’m pretty certain something has happened to cause minimserver to be ‘corrupted’.
Two sides to this – 1, what has happened, 2, how do I put it right.
Any pointers would be greatfully recieved.

[simoncn]

The MinimServer limit for recently added files is 300 by default. There is a configuration setting to increase this to a maximum of 1000.

As the BlueSound and JRiver apps show the artwork OK, it sounds like the problem might be with the Naim app's artwork cache. Can you try another app that uses MinimServer to confirm that MinimServer is returning correct artwork, such as BubbleUPnP or mconnect? I think there is a way to rebuild the Naim app artwork cache but I would need to do some investigation to find out how to do this. MinimServer doesn't use an artwork cache.

[paulr]

Thanks Simon. The recently added file does indeed contain 300 entries - therefore red herring.
Good suggestion to tryi other players/control point.
Bubble upnp not available for iOS.
Mconnect Lite (free) does not have a facility to connect to minim (not that I can see anyway).
I've installed VLC on my iphone, it connects to minimserver, and instantly displays what I expect, except not all artwork. I've checked a few albums and it looks like VLC is showing the album artwork as the naim app.
Gets a bit more murky as time goes on. How come Naim and VLC apps show the same artwork? Surely they have their own cache?

[simoncn]

I am not sure why you couldn't get mconnect Lite to find MinimServer. This does work.

In any case, your test with VLC shows that the issue is in some way related to MinimServer, as VLC is using artwork provided by and loaded from MinimServer.

MnimServer has a library cache (not an artwork cache) and it is possible that this cache might have been damaged or corrupted in some way. If so, I would expect that the library contents would not be displayed correctly.

To rebuild this cache file, do the following:
1) On the MinimServer Properties page, set the startupScan property to full
2) Do a MinimServer rescan

Does this show correct artwork with VLC?

[paulr]

Thanks Simon - re mconnect - I know it's not your software, but I can't see anything anywhere in the settings to display/connect to minim.....
I've done as you suggest regarding rescanning, it's running now.
On the naim forum (not an official support route) they have suggested trimming some of the larger artwork I do have as it may not be helping things anyway (42k of my 70k tracks are 1000 pixels or less and 2.8k at between 3k and 4k).

On a general note, is there info around the architecture of this stuff? (i.e. what a upnp server does, what it stores? what does the relevant app do (eg VLC/Naim), what does the app store? What does the player do? what does the player store?). What happens when I open an player app (e.g. VLC and display the library? How does the artwork get to my control point?

I'm asking because VLC was VERY quick to show me the contents (seconds), it cant surely have built it's own db/cache that quickly.....
I did have a scout around but couldnt seem to find what I was after. I hope you can understand where I'm coming from with wanting the info.
I'm very grateful for your input to date.
I'll report back once the scan has finished.

[paulr]

Good news!
Did as you suggested Simon and did the full scan - artwork is back! Naim seems to have caught up, VLC seems to be catching up....
Thank you for the input and suggestions, really appreciated.
I'm ok with 'these things happen' - at least now I know if the same happens again I can get round it.
I would though be grateful if I could be directed to info re the general questions above.

[simoncn]

(08-09-2025 14:52)paulr Wrote:  On a general note, is there info around the architecture of this stuff? (i.e. what a upnp server does, what it stores? what does the relevant app do (eg VLC/Naim), what does the app store? What does the player do? what does the player store?). What happens when I open an player app (e.g. VLC and display the library? How does the artwork get to my control point?

There is a 136-page document describing the UPnP architecture. For a very brief summary, see below.

In the UPnP architecture there is a server, a control point and a renderer. These can be dedicated hardware devices or software applications. Sometimes a single device plays multiple roles. The UPnP architecture defines the protocols that the server, control point and renderer use to discover each other on the network and communicate with each other.

The server manages the library and typically runs on the same device that is used to store the library files. It uses the UPnP protocol to communicate with the control point (for browsing the library and providing artwork and metadata from the library) and it uses the HTTP prrotocol for communication with the renderer (for streaming audio files). The server reponds to UPnP requests sent by the control point and HTTP requests sent by the renderer. The server doesn't send any UPNP requests itself.

The control point provides the user interface for browsing the library, showing metadata and artwork and selecting audio files for playing. In traditional UPnP, the server defines the library browsing structure/index and the control point sends UPNP requests to the server to navigate the library. More recently, some control points (for example, LUMIN and JPLAY) download the entire library contents and create their own library browsing structure using this information.

To play a file, the control point sends UPnP requests to the renderer specifying an HTTP URL to use for streaming the file. This URL typically points to the server but this isn't required. This gives the server the opportunity to perform various types of audio processing such as transcoding the audio to a different format or changing the volume level or frequency response curve.

Quote:I'm asking because VLC was VERY quick to show me the contents (seconds), it cant surely have built it's own db/cache that quickly.....

This means VLC is not using a cache for artwork or library contents but is reading this from the server every time (traditional UPnP).

[Edward630]

That does sound frustrating, especially with such a large library. A couple of things you could try based on my own headaches with MinimServer + Naim:

1. Rescan the library fully – not just a refresh. Sometimes Minimserver’s cache gets out of sync and artwork + “recently added” lists behave strangely until you force a proper rebuild.
2. Check the Minimwatch logs (if you’re running it) – they often show hidden errors like files it skipped or issues with reading embedded art.
3. Artwork size/format – Naim apps can be picky if artwork is unusually large (some recommend <1MB JPEGs, ideally square). Even if Bluesound and JRiver show it fine, the Naim app might choke on certain files.
4. Database corruption – I’ve had to wipe Minimserver’s cache folder and let it rebuild from scratch before, which sorted similar odd behaviour.

Since your Bluesound and JRiver are showing everything correctly, I’d lean towards it being a Minimserver indexing glitch rather than a file issue. If you haven’t already, maybe back up your Minimserver settings, clear the index/cache, and let it do a full rescan overnight.

Curious to hear if anyone else has had the same issue with the Naim app recently – could still be a compatibility quirk.

[paulr]

Simon, thank you for the info, helps to understand, apologies for late reply, I’ve only just seen it

[radiante]

Hi everyone.
I'm having a very similar problem. I use the Heos app to play files (stored on my NAS) through my Denon stereo. Until a couple of months ago, everything worked perfectly, but now the file covers only appear the first time. If I exit the disk and re-enter, the song images no longer appear.
Let me explain: the cover art for each song is tagged inside the song file itself in 500x500 jpeg format.
Using other apps (such as "hi-fi cast"), everything works perfectly.
I don't understand what the problem could be.