Displaying half-star ratings

[simoncn]

On reflection, it seems better for MinimServer to do as you have done and compute a weighted average rating for the album instead of using the rating from the first track. To ensure a meaningful result for different numeric rating scales, this would be rounded to the nearest rating value that appears on one of the album tracks.

[DanielB]

(15-11-2023 08:15)simoncn Wrote:  On reflection, it seems better for MinimServer to do as you have done and compute a weighted average rating for the album instead of using the rating from the first track. To ensure a meaningful result for different numeric rating scales, this would be rounded to the nearest rating value that appears on one of the album tracks.

That makes more sense for non-classical music where the best tracks are heavily front loaded.

The problem is that whilst I can change the track rating from the minimserver scale to 20-100 with tagupdate will I be able to do such a thing with the album rating, or is your average based off the changed values? I ask as the MediaMonkey app expects to see 0,20,40,60,80,100, not that I think it'll display album rating.

I have asked bubbleupnp if he could add rating and there seems to be some interest there so hopefully that will be an option in future too.

[simoncn]

The averaged album rating would be calculated after tagUpdate processing has happened.

While looking at the code to confirm this, I noticed some difficulties with computing a weighted average. The most serious issue is that the user can put any string into a RATING tag for a FLAC file, not necessarily a numeric value.

One way to resolve this would be to use the mode (the central value when the tagged values are arranged in sorted order). The values would be sorted with the numeric sort algorithm for strings that MinimServer already uses when sorting lists (so that Volume 9 comes before Volume 10, etc.) This is reasonably simple to implement but might produce surprising results in some cases. The other option is to continue with the current implementation of using the first value found, which is simpler to implement and to explain and understand.

[DanielB]

(16-11-2023 15:44)simoncn Wrote:  While looking at the code to confirm this, I noticed some difficulties with computing a weighted average. The most serious issue is that the user can put any string into a RATING tag for a FLAC file, not necessarily a numeric value.

Obviously I don't know all the issues you've found, so some of this may not be applicable/possible.

Before asking bubbleupnp to add ratings I did a little research so I'm basing this on that, and I'm assuming that you want to produce the average using the incoming scale (rather than 1-5).

The following rules apply to all tracks of an album.
- If any rating is outside of 1-100 then don't calculate a rating at all.
- If all tracks are between 1-5 then output the rounded average.
- otherwise average and round to 20,40,60,80,100 (this assumes you don't want to use half-points which you haven't for MP3's).

(16-11-2023 15:44)simoncn Wrote:  The other option is to continue with the current implementation of using the first value found, which is simpler to implement and to explain and understand.

I just don't think the first rating is of any value though, it's akin to displaying the maximum value of the album (assuming that good songs are front loaded).

The mode is an improvement but that assumes you use an evenly distributed rating, and I really don't like using 3/it's ok, so an album for me would probably be either 2 or 4.

I'm sorry if I'm coming across as being critical, I don't mean to be, but for me if it can't be calculated properly then I just wouldn't bother at all. I'm not aware of any control points that make use of it so it's not a loss.

[simoncn]

Thanks for this feedback. It is very useful because I don't use ratings myself, so I don't know what other users would expect or find useful.

At present, the computed album rating (first track value) is used in two places: the upnp:rating property sent to the control point in album metadata and (if specified) in tag formatting of the album title.

i think it is best for now to remove the computed album rating. This means that no upnp:rating property will be sent to the control point in album metadata, only in track metadata. If the user specifies $rating in Album.displayFormat, the default MinimServer behaviour (used for tags such as Artist and Genre) will apply. This is to create a combined value of all tagged values in the tracks of the album with duplicates eliminated and separated with commas.

[simoncn]

The change to remove computed album ratings is now available in MinimServer update 246.