Introduction

Upmpdcli is primarily an UPnP Renderer front-end to the MPD music player. It has a number of additional or alternative functions.

The next section explains the network audio terms (UPnP, Media Renderer, etc.) if your knowledge needs a little brushing up. Else, you can jump to the upmpdcli overview section.

Do not scrap your old amp yet, with 100 Euros (a Raspberry Pi and a high quality DAC I2S daugtherboard) you can transform it into a state of the art network streamer.

Security

Warning
The UPnP protocols have no security provisions. Upmpdcli is not audited for security issues, and, as far as I know, it is full of exploitable bugs. Do not run it on an Internet-facing host.

UPnP and all that

UPnP AV

UPnP is a family of network protocols, designed for easily connecting stuff in home networks (mostly). Its name ("Universal Plug and Play") was chosen because little or no configuration is needed for the different elements to discover each other and play together.

The UPnP audio/video section (UPnP AV) implements a way for data stored on a network host (PC, NAS, etc.) to be displayed on another one (TV, audio streamer, etc.).

Generally, there are four building blocks in a network audio solution:

  • An audio File/Data server stores the (bulky) audio data and makes it available to clients using an appropriate protocol (NFS, SMB, HTTP, etc. depending on client).

  • The directory/tags manager extracts audio tags from the files (usually accessing them directly or through a network file sharing protocol), and builds a database used for searching or browsing the collection.

  • Audio players (renderers) take encoded audio data and actually make sound, using some kind of DAC (Digital Analog Conversion) device, such as an internal or USB sound card.

  • The user interface is a remote control which sits in your hand (or it’s the PC in front of you). You use the application which runs on it to choose songs from the database and control the playback. It interacts both with the tags database and player parts (usually not with the file server, except maybe to fetch cover art).

Network Audio Elements
Figure 1. Network Audio

In the UPnP world:

  • The tags manager is named Media Server (more precisely, the Content Directory service inside the Media Server device). Data is usually stored on the Media Server, but it could also live elsewhere. Data access is almost always performed through HTTP.

  • The player is named Media Renderer. It usually does not implement much user interface.

  • The remote control is named Control Point

The good people who specified UPnP AV got something wrong: the playlist is owned by the Control Point, not by the Renderer. This means that the Renderer will not play the next track if the Control Point goes to sleep, and that havoc is almost guaranteed if several Control Points try to share a Renderer. This is the main reason for using OpenHome (see next).

OpenHome

The OpenHome family of open protocols were designed by Linn to correct the weaknesses in UPnP AV. They implement extended services over the base UPnP mechanisms.

Principally, the OpenHome playlist lives on the Renderer. It will continue playing if the Control Points goes to sleep, and it can be shared. This is a compelling advantage and most well-known Control Points (e.g. BubbleUPnP, Kazoo, PlugPlayer…​) support OpenHome.

Beyond this, OpenHome also defines additional services, for example for accessing Internet radios. The different possible origins of audio data inside an OpenHome Renderer are named Sources, e.g. Radio Source, Playlist Source. Sources are switchable from any Control Point supporting OpenHome.

OpenHome Sources are designated by a type and name, and a Renderer can have any number of them (for example, Upmpdcli uses additional sources to control its Sender mode).

Songcast

Songcast is an open protocol designed by Linn for real-time network audio. Its only relationship with UPnP is that UPnP services are used to control the connections. Songcast allows playing the same audio on multiple players, with almost perfect synchronization, or capturing audio on a computer to play it on another system.

The protocols links two types of entities:

  • A Songcast Sender generates an audio stream.

  • One or several Songcast Receivers receive and play the stream.

Linn supplies free audio capture drivers functionning as Songcast Senders, for MS-Windows and Mac OS X. This enables playing the audio of any application (Windows Media Player, Spotify, Tidal, etc.) onto one or several Songcast Receivers, without any need for the applications to know about Songcast.

Gapless ?

This is a relatively small issue, but people are very sensitive to it, it is important from some music pieces (Goldberg variations with gaps: not nice) and you will hear about it all the time if you read forums, so, a quick explanation follows.

Some music tracks need to flow into each other when played consecutively, for example tracks on some live albums (the background noise from the audience never stops), or some classical music pieces.

When playing from separate audio files, it is not trivial for a renderer to ensure a seamless flow: the audio hardware has an input pipe which must be kept full at all times, else it will stop, and a period of silence will ensue: not gapless !

To avoid this, the renderer has to know in advance which file it will process after the current one, to be able to begin filling the audio pipe with data from the next track before it empties at the end of the current one.

There are two ways that this can be achieved: either the renderer is also in charge of the play queue, so it knows the whole sequence all the time (e.g. MPD, OpenHome, …), or the controller indicates the next track to the renderer before the current track finishes (e.g. UPnP SetNextTransportURI).

Upmpdcli overview

Upmpdcli is primarily a UPnP Media Renderer frontend, using a slave MPD to actually process the audio data. It supports UPnP gapless track transitions and the OpenHome ohMedia services (including a Radio service to listen to Internet streams).

The Grand Scheme of Things
Figure 2. The Grand Upmpdcli Scheme of Things

Additionally:

  • Upmpdcli implements control functions for the Linn Songcast protocol, allowing the local machine to behave as a Songcast Receiver or Sender (with help from the closely related sc2mpd package, for processing the audio streams).

  • Upmpdcli provides a Media Server interface, mostly used for accessing external streaming services (Spotify, Highresaudio, Qobuz, Deezer). The uprcl module provides a local Media Server based on the Recoll medata extraction and search functions.

Upmpdcli can be installed on most Linux systems. It is frequently used on small single board computers like the Raspberry Pi. As far as I know, all audio-oriented distributions currently use it as their UPnP Media Renderer interface, and it is also present in a number of commercial devices.

Upmpdcli is mostly configured through values set in a configuration file but, for basic operation without a configuration file, a few of the main parameters can be set on the command line or in the environment.

Most parameters can only be set in the configuration file, which is designated with the -c command line option. The usual location is /etc/upmpdcli.conf.

The configuration file has a simple name = value format, and is fully described in the configuration reference section.

upmpdcli has many configuration parameters, which may make the configuration intimidating. However, most parameters only relate to one function of the program and they are grouped in sections, many of which are probably not relevant to you. In each section, the most important parameters are presented first, and you probably will never need to bother with the bottom of the list.

The upmpdcli-config graphical tool can help you edit the configuration file, it can present the same information as this manual, directly linked with the controls used to modify the parameters.

Upmpdcli Media Renderer

This section goes in a little more detail about miscellaneous aspects of the Media Renderer, and describe a few of the most used configuration parameters. See the configuration reference section for more details (I would very much like to link each parameter to its definition but Asciidoc won’t let me do it, so they link to the top of the appropriate section.).

If several instances of upmpdcli run on the same network, you will want to give them distinct names. The name which is displayed by most Control Points can be set with the friendlyname configuration parameter. Some Linn Control Points (e.g. Kazoo) use another value, set with ohproductroom.

Upmpdcli usually controls the MPD instance running on the same host. However, there may be reasons to do otherwise, and the host name and port where mpd should be reached can be set with mpdhost, and mpdport.

The Upmpdcli Media Renderer has two active interfaces by default: UPnP AV and OpenHome. Only OpenHome Control Points can share the renderer. If you use an UPnP AV Control Point, it must be the only one. This is not enforced, and misuse will result in miscellaneous weirdnesses. In some special situations, it may be useful to limit the interface to UPnP AV or OpenHome only (or disable both), which can be done with the openhome and upnpav parameters.

Audio formats

Upmpdcli can accept most audio formats supported by MPD, meaning about anything, including DSD.

Upmpdcli normally checks that the format of a resource to be played is compatible with what it thinks MPD can do. This check is sometimes pessimistic and can be disabled by setting checkcontentformat to 0.

You should know that MPD has difficulties with some formats when accessed through HTTP which is how the Media Server transfers the data.

Specifically, WAV and AIFF files, especially with samples wider than 16 bits are a frequent source of trouble (because they are little used and little tested for streaming). Support will vary depending on the MPD versions and exactly what input plugins are configured (among ffmpeg, libaudiofile and libsndfile). Often, the same files play just fine locally, it’s the combination of HTTP access and file format which causes problems.

Raw PCM streams are another special case. The reason is that these streams do not, by definition, carry metadata to define the exact format (sample rate, bits per sample, number of channels, byte order). upmpdcli has no way to transfer these parameters to MPD (this is a limitation of the client protocol). The parameters can be transferred from the Media Server to the player along with the MIME type though. In consequence, only recent versions of Upmpdcli and MPD (0.20 and later) do support audio/L16, but not with any Media Server (it must output the audio formats parameters with the MIME type). See this issue for more details: https://www.lesbonscomptes.com/upmpdcli/github-issues/upmpdcli-html/issue-36.html

In general, there are few reasons to use these linear formats, when FLAC will produce exactly the same bits, with less network load (which largely compensates the small additional CPU load).

There are situations where the linear formats are needed though, and where it may be necessary to use the right MPD and plugins versions.

Radio stations

Upmpdcli implements an OpenHome Radio service which allows selecting and listening to internet radio stations when using an OpenHome-compatible Control Point (e.g. Kazoo, Lumin, Bubble UPnP, etc.).

This facility uses Python 3.x, which must be available on the system for the radio links to work.

Radio channels can be accessed by using the Control Point application to select the Radio OpenHome source.

Radio stations can be defined in the configuration (at the end because of the use of section indicators), or in in a separate file by setting the radiolist parameter in the main configuration.

An example of a simple radio station definition follows. The only mandatory value is the url one, which should point to the actual audio stream or to the station playlist link which will redirect to it (more detail in the radio scripts section. artUrl points to a static logo image for the station.

[radio Radio Eins]
url = http://opml.radiotime.com/Tune.ashx?id=s25111
artUrl = http://cdn-radiotime-logos.tunein.com/s25111q.png

Radio definitions may also include paths to scripts to be executed for retrieving the metadata and album art for the currently playing song. See the radio scripts section for more detail.

Upmpdcli and Songcast

Upmpdcli implements the Receiver UPnP service, and uses an auxiliary process (sc2mpd) for transporting the audio data. sc2mpd is based on the sample program which comes with the Linn Songcast OpenHome open source implementation

Upmpdcli can also manage a Sender subsystem, which is implemented by using a separate mpd instance sending audio to an mpd2sc command (part of the sc2mpd package). The latter is a modified version of the OpenHome WavSender sample program. This allows playing the usual Upmpdcli playlist or a a radio channel on several synchronized players, but also doing the same thing with a captured analog source (e.g. arecord output).

Note
You should know that it is possible to control the Songcast Sender from another local network PC to snoop on what you are listening (Radio or Playlist). This is detectable from the Renderer state, but not obvious. In any case, the playlist itself is public (there are no privacy provisions in UPnP), so this is probably not a major additional issue. The system will not capture anything besides what mpd, or an explicitely setup additional source are playing (e.g. Skype phone conversations are out of reach).

Upmpdcli Songcast Control Point compatibility

Upmpdcli Senders and Receivers can be mixed with Linn ones and controlled from Upplay or Bubble DS (an maybe other control points).

Neither Linn nor upmpdcli receivers can be linked to an upmpdcli Sender using Linn Kazoo (tested with release 4.11.226), the reason is unknown.

Upmpdcli Receivers before release 1.2.14 are not visible in Linn Kazoo. Later versions can be linked, and stream, from a Linn Sender.

Linn Kazoo can control the playlist in an upmpdcli instance which has been put in Sender mode by another CP (i.e. currently using the PL-To-Sender source). The Lumin IOS app will reset the Source to Playlist when connecting, so it is unusable in this context.

Upmpdcli Songcast Receiver

sc2mpd can play the Songcast audio stream in two modes:

  • By directly using the alsa audio driver.

  • By using mpd to play the stream offered from a local HTTP interface (hence the sc2mpd name)

Table 1. Upmpdcli Receiver in alsa and mpd modes
alsa mpd

Upmpdcli Receiver

Upmpdcli Receiver

What approach is used is decided by the scplaymethod configuration parameter, which can be set to mpd or alsa.

The mpd mode is the default, because it needs no configuration, but there are multiple problems with it. If you go the alsa route, you will need to set scalsadevice in the configuration, but you probably had to set it in the MPD configuration too, so this may not be too much of an issue.

Note
when using the alsa approach, sc2mpd will open the audio driver directly. The sc2mpd process is started by upmpdcli, which normally runs with user id upmpdcli. A frequent cause preventing the Receiver from working is that the driver open fails because upmpdcli user has no permission to access it. One solution is to create an audio group (if it does not exist), make the devices writable by audio, and add upmpdcli (and others) to the audio group.

When using mpd, more bufferisation occurs and there may be a significant delay (up to around 10 S) between the time when Songcast is activated and the time sound appears.

Note
When using mpd, from a Mac (24 bits audio) you need an appropriately configured and recent MPD version (usually configured with --disable-audiofile), else you risk producing high volume noise. As Debian and Ubuntu tend to lag quite bit on MPD progresses, I have set up backport repositories for appropriately configured recent mpd versions, for Ubuntu, Debian i386/amd64 and Raspbian. Unfortunately, not only the MPD version is significant, there are sometimes also problems in the input plugins libraries.

Given the bufferisation and delay control issues when going through MPD, only the alsa method is usable in multi-room configurations. Even with a single player, the mpd method will experience skips from time to time. The reasons are explained in the multiroom synchronization section.

The following steps are taken for establishing a Songcast connection:

  • If upmpdcli finds an executable sc2mpd command in the PATH when starting up, it advertises a Receiver service.

  • The Songcast application on the desktop finds out about the Receiver through the normal UPnP mechanisms and can be instructed to use it. It then tells the Receiver in upmpdcli to start playing.

  • upmdpcli starts the sc2mpd process, which gets ready to receive data through Songcast, and either play it directly or make it available through HTTP.

  • If the `mpd` method is in use, upmpdcli instructs mpd to play the URL for the sc2mpd output.

Note
Songcast can use IP multicast for lower load on the network when playing on several hosts. Unfortunately, multicast and WIFI don’t mix well in many cases. If you have wireless Receivers experiencing sound drop issues, try selecting unicast in the Songcast advanced configuration panel on the desktop.

Songcast Receiver Volume control

This section used to claim that the upmpdcli Songcast Receivers implemented no software volume control and that you needed to use either a local mixer or the little round things on the pre-amps.

Actually, as of sc2mpd version 1.1.6, there are two possible ways to control the volume on an upmpdcli Songcast receiver, one of which has existed for a long time. Both approaches are based on the fact that a control point connected to the upmpdcli instance can set the volume level using the normal UPnP/OpenHome interfaces.

The first method, which has been available for a long time is to use the externalvolumecontrol feature, and set up the corresponding scripts to set and retrieve the volume from the audio mixer (e.g. using amixer or such). This will adjust the volume without any change to the Songcast stream.

The second method, available for sc2mpd versions 1.1.6 and later can scale the audio stream according to the local mpd volume setting. The volume control goes from the control point to upmpdcli, which sets it in mpd, from which sc2mpd retrieves it to set the scale factor. This is not active by default, you can enable it by setting the scusempdvolume variable to 1 in the local upmpdcli.conf. This only works if if scplaymethod is alsa.

Upmpdcli Songcast Sender

Upmpdcli Sender mode allows you to broadcast the Playlist or Radio source (or the output of any process which can write to a Fifo, e.g. arecord) to other Songcast Receivers. The local upmpdcli plays through its Receiver too, in order to achieve good synchronisation. Unlike the Songcast applications on Windows or Mac, the audio is not captured from the driver, so that you won’t be able to cast other applications transparently (but there are specific workarounds).

You can set umpdcli in Sender mode from an OpenHome Control Point, by selecting the Source of type Playlist, name PL-to-Songcast or type Radio, name RD-to-Songcast (and others if using the extension mechanism). With upplay, for example, you can select the source from the File→`Select Source` menu entry.

The sc2mpd configuration must be set with scplaymethod = alsa for the XX-to-Songcast sources to appear. See the configuration section, and the section about synchronisation.

When entering Sender mode, upmpdcli will start an auxiliary MPD process (after stopping the main one), configured to send audio to the mpd2sc OpenHome Sender process. It will then also start its own Songcast Receiver mode, transfer the playlist, stop the main MPD and start the auxiliary one…​

The resulting state is that the upmpdcli instance can be managed in Playlist mode from the Control Point. The audio is played locally through the Songcast Receiver. Other Receivers can be connected and will play in good synchronization.

Sender/Receiver mode

This looks complicated, but in practise, starting the mode and connecting other Receivers from the upplay control panel is quite straightforward.

Managing external sources

In the Sender modes described above, upmpdcli (or rather its slave mpd process) is the source of the audio stream. The mpd2sc program (which is just a slight modification of a Linn sample) reads the mpd output from a FIFO and sends it to Songcast Receivers (including the local one).

There is nothing special with the mpd output (it is just PCM audio), and it is also possible to set things up for mpd2sc to read from another source.

This is made reasonably easy because the pipe is actually built by a script (the default one is named 'scmakempdsender'), and upmpdcli has built-in functionality for choosing different ones (creating OpenHome sources for each script it finds in a specific directory). There is a sample script in the distribution, which itself is flexible enough to allow connecting several inputs without programming (anything arecord can read).

Still the details are a bit too much involved for the main body of the manual, so I have moved them to an annex.

Songcast multiroom configurations and synchronization issues

Multiple Songcast Receivers can connect to the same Sender, for synchronized playing of a the same audio stream.

The Mac and Windows Songcast applications only let you activate one Receiver.

The easiest way to manage multiple connections is to use an appropriate control point, such as Upplay on Linux and Windows, BubbleDS on Android, or Linn Kazoo (multiple platforms).

For the record, the upmpdcli package also includes the scctl command line utility, which can list the state of the local Songcast Receivers, make a Receiver play from the same URI as another one (for building multi-room groups), or return a Media Renderer from Receiver to normal operation. There is also a small Web application which can be accessed from a desktop web browser to control the groups. This has only be tested with upmpdcli as Receiver implementation, but I’d guess that there is a good chance it would work with others. Quite frankly, I think that you’d better use the Control Point approaches if at all possible.

Synchronisation issues

The short version is: for good syncrhronization, all sc2mpd instances must be configured to play directly to the audio driver with scplaymethod = alsa. See the configuration section.

Longer version: Songcast is a real-time audio stream. As the Sender and Receiver sample clocks (the 44.1 or 48 KHz clocks) are independant, audio reproduction on the two systems will slowly drift. If nothing is done, after a time, the Receiver will have to skip samples or add a period of silence (depending if its clock is slower or faster), which is quite audible and ennoying, and will happen "from time to time", depending of how much the clocks differ.

The only way to control this is to adjust the rate of reproduction on the Receiver, which can be done in two ways:

  • Linn hardware uses timestamps embedded in the audio stream to adjust their hardware sample clock.

  • sc2mpd in alsa mode uses sample rate conversion to adjust the stream.

  • sc2mpd in mpd mode can’t do a thing about it.

This is not specific to Songcast of course, all real time audio network transports have to do something similar (e.g. Roon does individual stream adjustments on the server).

Independantly of the clock issue, all Receivers should use approximately the same amount of buffering for the audio to be reasonably synchronous (with no more shifts than moving around would produce anyway). This is impossible to achieve when going through mpd, and the second reason why sc2mpd must be set in alsa mode for multiroom setups. In mpd mode, the Receivers can be out of sync by several seconds.

Support for Streaming Services

Streaming Services and UPnP

Streaming services like Highresaudio or Spotify give access to a huge catalog of music through a WEB programming interface which is also usable by programs other than their own applications.

The only thing that they have in common with UPnP is that most of them use HTTP to retrieve the audio stream (as a short-lived URL). Spotify is an exception, and uses a specific protocol for streaming.

Given the importance of these services for music consumers, many UPnP Control Points and Renderers have been extended with specific interfaces to the different services.

There are three main ways to integrate the streaming services in an UPnP framework, and knowing which way you are using will avoid confusion:

  • The first approach is to have a UPnP Media Server act as a proxy for the service: the catalog is browsed through a standard UPnP interface (the Media Server translates this to the service API behind the scenes), and the audio URIs are also accessed in an almost standard way (after a bit of magic inside the Media Server). The one inconvenient of this approach is that the special functions of the service (like managing the user favourites lists) are mostly inaccessible. The advantage is that any naive UPnP Control Point can access the streaming service. The Media Server inside upmpdcli implements this method.

  • The second approach is to do everything inside the Control Point. The CP uses the service API for browsing (and possibly do things like managing favourites). The CP also mediates the HTTP access to the audio streams (the URIs the CP sends to the Renderer point to itself, and it arranges to forward the data from the service). This is implemented, for example, by Bubble UPnP. The drawback of this approach is that the Control Point device must not go to sleep or out of reach, else the music will stop (maybe at the next track).

  • The third approach is to distribute the function between CP and Renderer. The Control Point performs the browsing and access to special functions, and the Renderer knows how to access the service streams. This is the OpenHome approach and can be considered the best of both worlds, at the price of complexity and compatibility issues. This method is implemented by the Linn Kazoo Control Point, and a number of Renderers, the Linn and Lumin ones of course, but also, lately by upmpdcli.

    • At the moment, the upmpdcli implementation is not useful any more, as changes in services access methods have made it such that none of them is currently usable with upmpdcli through this method.

Accessing Streaming Services through the upmpdcli Media Server

The Media Server function in Upmpdcli gives access to external streaming services: Spotify, Highresaudio and Qobuz currently work unconditionally (1.5.5). I am not sure about Tidal support: in any case it will only work if you can find a working application token (Tidal), and even then, maybe not as their access control API is evolving.

A plugin for Deezer has been added recently (2021-02-23 git or future 1.5.9), and currently only provide access to 128 kb/s mp3 streams.

You will need a valid subscription for any service that you want to use (for Spotify, this means a premium account, the free ones will not work).

When the function is activated, upmpdcli creates a separate auxiliary Media Server, with the sole purpose of presenting the streaming server catalog. You will see it appear on the network if streaming service parameters are present in the configuration file. The Media Server name is the friendlyname for the Upmpdcli instance, with -mediaserver appended.

Streaming is not limited to the local Upmpdcli Renderer, and the Media Server will happily send music to other Renderers (within the limitations set by the service).

Two conditions must be true for the Media Server to appear with an entry for a streaming service:

  • The code for the service plugin must be installed. This comes generally in a separate package (e.g upmpdcli-qobuz).

  • The user variable for the service must be present in the configuration file (e.g qobuzuser).

Some other parameters (e.g. a password) may be needed for the access to work, depending on the specific service. See the service-specific notes below.

Note
The streaming services passwords are stored in the upmpdcli configuration file ('/etc/upmpdcli.conf'). The installer does not make this file r/w by owner only. You should probably change the mode after setting the password: chmod 600 /etc/upmpdcli.conf.
Note
I have no reason to believe that upmpdcli is technically mis-using the streaming services in any way, but it is definitely not approved by any of them, and you are using it under your own responsibility.

Using Qobuz through the Upmpdcli Media Server

This is based on the service API from the Kodi add-on, by Joachim Basmaison and Cyril Leclerc, with the upper-level code adapted from the Tidal add-on. The WEB API is not officially supported by Qobuz, and may just stop to work one day.

Note
the Qobuz search does not allow searching a specific field (like the artist name or song title). All objects matching a query in any field are returned. This means that, e.g., the field choice of upplay search is ignored.

You need a valid Qobuz subscription.

The configuration parameters are described in the configuration section

Using Deezer through the Upmpdcli Media Server

You will need a premium (paid) account.

The plugin is based on code from the Kodi add-on, by Jakub Gawron (kubatek94) and ? (Valentin271).

It uses the Deezer "television" API and only provides access to 128 kb/s MP3 streams.

The configuration parameters are described in the configuration section. Only deezeruser and deezerpass actually.

Using Spotify through the Upmpdcli Media Server

You will need to install the upmpdcli-spotify module.

You will need a premium account, the free ones do not work for this.

Spotify is the only service which does not use regular (short-lived) HTTP URLs for accessing the streams, but rather a non standard transfer protocol, implemented in a specific library.

The upmpdcli interface is based on a slightly modified version of the Spotipy Python package and the old libspotify library.

The libspotify library is not distributed or installed with upmpdcli, you need to install it separately. Currently, the easiest way to obtain it is from the Mopidy repository. You can use the 'deb' packages on a Debian-derived system, else copy the dynamic object for your architecture to /usr/lib.

Note
Using this module is contrary to the current Spotify terms of service, and you use the (supposedly deprecated) library under your own responsability.

The authentication method is also more complicated than for the others, and will have you jump through a few hoops in addition to setting the password in the configuration file.

You will need to set some configuration parameters, which are described in the configuration section and then obtain an oauth2 authorization token: follow the instructions in the Spotify authorization annex.

Upmpdcli radio list plugin

This is a minuscule plugin which just exports the Upmpdcli radio list as a playlist, so that other renderer on the network can use it.

Of course, the functionality is reduced when compared to using the list through the upmpdcli’s own OpenHome Radio service: there will be no dynamic art or special metadata features: artScript and metaScript entries are just ignore.

Still the server will convert .pls and other playlist entries into actual stream URLs, and it may be convenient for maintaining the radio list in one place.

Upmpdcli local Media Server: uprcl

You will need to install the upmpdcli-uprcl module.

The current (2020-12) upmpdcli code base includes a Media Server function for local music files, analog to MinimServer or ReadyMedia/MiniDLNA. The plugin module is named uprcl.

Why yet another Media Server ? Mostly because my favorite, MinimServer is great, and free, but not open-source, so I find it prudent to have an alternative. Also, fun :)

uprcl only implements a small fraction of MinimServer vast list of capabilities at this point, but it’s slowly making progress, and I find it works well enough, at least with the upmpdcli renderer, to now be my main Media Server.

Some uprcl features:

  • Mostly written in Python, except for the part shared with the streaming media server plugins, which is in C++.

  • Tries to mimick the MinimServer tree view and functionality. We’re not quite there yet, many functions and niceties are still missing.

  • Uses Recoll and python-recoll (hence the uprcl name) for harvesting the metadata and searching.

  • Uses Python Sqlite3 (on a memory DB) for the tags tree.

  • Can retrieve some parameters from the MinimServer configuration file. Will support more in the future.

The list of MinimServer functions which are not supported would be too long. Here follows what uprcl does support, at least partially, at this point (1.4.3pre):

  • contentDir will be used if uprclmediadirs is not set in '/etc/upmpdcli.conf'

  • excludePattern

  • aliasTags

  • indexTags

  • showExtras

  • Multidisc albums (partial).

All in all, not a lot of the customization options are supported for now. I’d love feedback about what is missing most.

Installation and configuration: have a look at the configuration variables

Note
uprcl needs Python 3.5 at least. This means that it does not work on Debian Jessie (8.x)
Note
'python-mutagen' which is optional for default Recoll installations is required for uprcl (this is for the case where you install by hand, the package takes care of it).

The UPnP Media Server search function is based on a specific query language. This language is quite verbose, and most control points will not let you access it directly. Instead, they will usually provide a generic entry field in which you enter search terms. Behind the scenes, they generate an UPnP search language string. This could be for example something like: upnp:class = "object.item.audioItem" and dc:title contains "heaven"

If it supports search at all, the Media Server will then interpret the query string and return the results.

If the Media Server is Upmpdcli/Uprcl, there is another step: the UPnP query string is translated into a Recoll one and Recoll is called to perform the actual search. There is no way to directly enter a Recoll search through the control point. However, two important Recoll capabilities should still be visible through the layers:

Stemming

Stemming is the capability to expand a search to the common derivatives of a word. For example, a search for floor would be expanded to also look for floors, flooring, floored, etc. By default, stemming is enabled for Uprcl search. It can be turned off for any term by capitalizing the term (Entering Stones will only search for stones, not stone or stoned). Uprcl/Recoll searches are case-insensitive apart from this usage of capitalization.

Phrase searches

By default, Uprcl/Recoll searches do not observe the order of terms: red house will be matched by a search for house red (or houses red). You can change this behaviour by quoting a sequence of words. A search for "red house" will only look for a text containing the words in order. This supposes that the Control Point does not change the user entry, but this is the case for at least some of them. Stemming expansion does not occur within phrase searches.

Other Recoll capabilities, such as proximity searches should also be accessible, but probably less useful when searching music titles or artist names.

Upmpdcli configuration file reference

Upmpdcli configuration

Upmpdcli general parameters

logfilename

Log file name. Defaults to stderr. This can also be specified as -d logfilename.

loglevel

Log level. Can also be specified as -l loglevel.

pkgdatadir

XML and other constant data storage directory. Default: '$prefix/share/upmpcli' (e.g.: '/usr/share/upmpdcli').

pidfile

Name of lock file used to store the current process pid. Only used if the process is launched by user root. Used by the init system, and to avoid multiple instances. The only reason to change the value is if you actually want to have several instances running (also change cachedir in this case).

UPnP network parameters

upnpiface

Network interface to use for UPnP. libupnp/pupnp only supports communicating on a single interface and will use the first found, this allows forcing the use of another interface.

upnpip

IP address to use for UPnP, alternative to using an interface name.

upnpport

Port number used for UPnP. libupnp/pupnp defaults to using the first free port after 49152. Note that clients do not need to know about the value, which is automatically discovered.

useipv6

Enable use of IPV6. By default we only use IPV4.

Media Renderer parameters

friendlyname

"Friendly Name" for the Media Renderer. This will be displayed by most Control Points to identify the Renderer. Some OpenHome Control Points may display the 'ohproductroom' value instead.

avfriendlyname

Specific friendly name for the UPnP/AV Media Renderer. The default is to append "-av" to the friendlyname value.

upnpav

Enable UPnP AV services (0/1). This is set by default, but it may useful to switch it off with some OpenHome Control Points which are too easily confused by the presence of UPnP AV services.

openhome

Enable OpenHome services (0/1). This defaults to 1, as OpenHome queuing is superior for most usages. There should be little reason to turn it off.

lumincompat

Disable the OpenHome Credentials service. At some point, this was necessary to enable Lumin to see upmpdcli instances: for some unknown reason, Lumin 1.10 did not discover upmpdcli with Credentials enabled. Credentials does not work at this point anyway (12/2020), but it is enabled anyway, because some Kazoo versions crash if it is not enabled.

ohinfotexttodata

Store metadata into the OpenHome "metatext" variable. The OpenHome Info service are supposed to hold different data, mostly for radios, with permanent radio data (icon, url, radio name) set in the "Metadata" variable, and information about the current title recorded in the "Metatext" variable. Setting this option will have upmpdcli store any non-empty Metatext data in the Metadata variable. This will help some players display the album art for the current title (e.g. Kazoo).

saveohcredentials

Save the streaming services login parameters to disk. This allows sharing the password with the upmpdcli media server streaming service proxy, if you are also using it. Avoids having to enter the password in the regular configuration file. Depending on your situation, you may see this as a security risk. The default is true, because I don’t see this as a real issue in the general case.

checkcontentformat

Check that input format is supported. Extract the protocolinfo information from the input metadata and check it against our supported formats. Set this option to 0 if a control point or media server sends good audio data with bad metadata.

opensslcmd

Path to the openssl command The OHCredentials service needs openssl 1.1.x or newer. Path to the openssl command to use if the system one (in /usr/bin) is too old. Not set by default.

iconpath

Path to the Renderer icon. The image will be displayed by Control Points which support it. The UPnP protocol has provisions for a renderer to send the URL to a descriptive icon as part of the device description. Due to current (and probably permanent) upmpdcli limitations, the image file must be a 64x64 32 bits-per-pixel png file. Default: '$pkgdatadir/icon.png'. The icon will only be read once, when upmpdcli starts up.

cachedir

Directory used to store cached data Only used for the OpenHome queue metadata for now. The default value is ~/.cache/upmpdcli for normal users or /var/cache/upmpdcli when upmpdcli is started as root.

presentationhtml

Path to the presentation HTML document You can change it to replace the default presentation page. The page will only be read once, when upmpdcli starts up. It can’t presently be used for status updates (but I guess that you could put a redirect in there, to something more dynamic served by a real HTTP server). Default: '$pkgdatadir/presentation.html'.

enablel16

Advertise L16 format support L16 is a raw linear 16 bits audio stream and the source of many issues because it does not include identifying information. It is disabled by default, only enable it if you know that you need it.

MPD parameters

mpdhost

Host MPD runs on. Defaults to localhost. This can also be specified as -h host

mpdport

IP port used by MPD Can also be specified as -p port. Defaults to the normal MPD port, 6600

mpdpassword

MPD password. Password for connecting to MPD (only necessary if password access is enabled in the MPD configuration file).

mpdtimeoutms

MPD connection timeout in milliseconds. If this is not zero, dialogs with mpd will timeout after the value. This will allow upmpdcli to stay responsive (return errors) if MPD ever becomes stuck.

ownqueue

Set if we own the MPD queue. If this is set (on by default), we own the MPD queue and will fearlessly clear it. Can also be specified as -q 0|1.

Audio control hooks

onstart

Command to run when playback is about to begin. Specify the full path to the program, e.g. /usr/bin/logger.

onplay

Command to run when MPD state switches to "PLAY". Specify the full path to the program, e.g. /usr/bin/logger.

onpause

Command to run when MPD state switches to "PAUSE". Specify the full path to the program, e.g. /usr/bin/logger.

onstop

Command to run when MPD state switches to "STOP". Specify the full path to the program, e.g. /usr/bin/logger.

onstandby

Command to run when the setstandby action is called. Specify the full path to the program. It is called with one 0/1 argument to change the standby state (1 for activating standby), and with no argument to query the state. In all cases, it should print the standby state (0/1) to stdout before exiting.

externalvolumecontrol

Use external command to manage the the sound volume (0/1). This is used in the case where MPD is unable to control the volume, but some other command can, for example if you have an external amp on which it is possible to set and read the volume through scripts. If set, the calls to MPD to set and read the volume will be replaced by executions of 'onvolumechange' and 'getexternalvolume'

getexternalvolume

Command to run for reading the sound volume. The command should write a 0-100 numeric value to stdout.

onvolumechange

Command to run to set the volume. Used when 'externalvolumecontrol' is set. Specify the full path to the program, which is called with the volume as the first argument, e.g. /some/script 85.

UPnP/AV tweaking

avtautoplay

Automatically fake a Play command when track is set. The UPnP/AV SetAVTransportURI, used to set the track to play, normally does not change the current transport state: an explicit Play command is required to start playing if the transport was stopped. Setting this parameter will synthetize a Play command after receiving SetAVTransportURI. This is needed by some control points which do not send the Play command.

OpenHome parameters

ohproductroom

The name of the room where the Product is located. Set to “Main Room” by default, displayed in place of the "friendly name" by some control points. ProductRoom is used to group the Product with other related Products in the same physical room (e.g. a source with a pre-amp). Products which are physically linked must always share the same ProductRoom name.

radiolist

Path to an external file with radio definitions. Radio stations can be defined in this file (main configuration file), or in an external file (or both). Using an external file can ease distribution to multiple machines, makes things clearer and is now the default. See the distributed file (name below) for information on how to define a radio station. In case you want to define radios in the main configuration file, they MUST occur at the end of the file (because they are defined as subsections, the last of which extends to the end of the file).

radioscripts

Radio metadata scripts directory. Path of a directory where the scripts used for fetching the channel metadata are located. The default is /usr/share/upmpdcli/radio_scripts. Note that the scripts are always first looked for in the locations defined by $PATH.

ohmanufacturername

Manufacturer name.

ohmanufacturerinfo

Manufacturer information.

ohmanufacturerurl

URL for manufacturer web site.

ohmanufacturerimageuri

Uri for manufacturer’s logo.

ohmodelname

Model name.

ohmodelinfo

Model information.

ohmodelurl

URL for model web site.

ohmodelimageuri

Uri for model’s icon.

ohproductname

User-visible product name. By default this is set to ModelName.

ohproductinfo

Product information.

ohproducturl

URL for product web site. This may be the UPnP presentation page.

ohproductimageuri

Uri for product image.

ohmetapersist

Save queue metadata to disk (0/1). This allows persistence of the metadata information across restarts, the default is 1, and there is no reason to turn it off.

ohmetasleep

Mimimum interval (Seconds) between two cache saves. Increasing this may improve playlist load speed on a slow device. The default is to start a new save as soon as the previous one is done (if the list changed again inbetween).

Media Server general parameters

msfriendlyname

Friendly name for the Media Server (if enabled). The default is to append "-mediaserver" to the friendlyname value.

plgmicrohttphost

Hostname/IP address used in proxy URLs. The default is to use the same host/address as the UPnP server. Using localhost/127.0.0.1 instead loses the ability to stream to a remote renderer, but allows for portable playlists.

plgmicrohttpport

IP port for the tidal/qobuz local HTTP service. The URLs for tracks streamed from these services point to a local microhttpd server running on this port (it uses redirection to the actual service URL when actually streaming). The default is 49149.

plgproxymethod

Decide if we proxy (copy: fetch/serve), or redirect the streaming services streams. Using redirect is much more efficient, but the proxy has a facility to retry when a stream is dropped by the service, which seems to happen esp. with Qobuz.

msiconpath

Path to the Media Server icon. The image will be displayed by Control Points which support it. Due to current (and probably permanent) upmpdcli limitations, the image file must be a 64x64 32 bits-per-pixel png file. Default: '$pkgdatadir/icon.png'. The icon will only be read once, when upmpdcli starts up.

Highresaudio streaming service parameters

hrauser

Hra user name. Your Hra login name.

hrapass

Hra password. The password for your Hra account.

hralang

Hra language setting (en/de). Some Highresaudio messages will be set in the appropriate language.

Spotify streaming service parameters

spotifyuser

Spotify user name. Your Spotify login name.

spotifypass

Spotify password. The password for your Spotify account.

spotifybitrate

Spotify preferred bitrate: 160 (default), 320 or 96. Unverified.

Tidal streaming service parameters

tidaluser

Tidal user name. Your Tidal login name.

tidalpass

Tidal password. The password for your Tidal account.

tidalapitoken

Tidal API token. The default token distributed with upmpdcli does not work any more. You will need to find a valid token and set here for the access to work.

tidalquality

Tidal stream quality. 'low' and 'high' are aac streams. 'lossless' is FLAC and will only work if your subscription allows it.

Qobuz streaming service parameters

qobuzuser

Qobuz user name. Your Qobuz login name.

qobuzpass

Qobuz password. The password for your Qobuz account.

qobuzformatid

Qobuz stream quality. 5 for mp3/320, 7 for FLAC, and 27 for hi-res (if your subscription allows streaming each of the formats).

Deezer streaming service parameters

deezeruser

Deezer user name. Your Deezer login name.

deezerpass

Deezer password. The password for your Deezer account.

Local Media Server parameters

uprcluser

Bogus user name variable. Used for consistency with other Media Server plugins to decide if the service should be started (so, do set it if you want a Media Server).

uprcltitle

Plugin Title. This will be displayed as the plugin entry in the Media Server root directory.

uprclhostport

HTTP host and port for serving media files The Media Server HTTP server will run on this address and port, which will also be inserted on the URLs we produce. If the variable is not set, we will use port 9090 and the first non-loopback ipv4 address in "ip addr" output, which may be right or not. Example: 192.168.1.1:9090

uprclconfdir

uprcl Recoll index directory This is usually not defined and defaults to /var/cache/upmpdcli/uprcl. The name is a bit misleading because there is little real configuration data in there: it’s mostly programmatically generated from actual configuration found elsewhere (but also see uprclconfrecolluser).

uprclconfrecolluser

Name of the user Recoll config additions file This is the name of a file with additional parameters for the uprcl recoll.conf file, to which the contents will be appended before indexing. The default is /var/cache/upmpdcli/uprcl/recoll.conf.user. If set, should be an absolute path.

uprclminimconfig

Name of the Minim Server configuration file If set, this is the name of a Minim Server configuration file from which we should fetch parameters like aliasTags, etc. (See the manual). Not set by default, and optional.

uprclmediadirs

Media directories This is a space-separated list of directories to explore for music files. This is used directly as the recoll "topdirs" value, so you can use double-quote quoting for paths with embedded spaces. If not set, we will try to use contentDirs from the Minim config.

uprclpaths

Path translations. Translations from real paths to ones relative to the HTTP server doc tree. If this is not set, uprcl will use a null translation for each of the uprclmediadirs entries.

Upmpdcli Radios plugin parameters

upradiosuser

Bogus user name variable. Used for consistency with other Media Server plugins to decide if the service should be started (so, do set it if you want to see the radio list).

upradiostitle

Plugin Title. This will be displayed as the plugin entry in the Media Server root directory.

Songcast Receiver parameters

sclogfilename

Log file name for sc2mpd (default stderr) The value must not be the same as the one used for upmpdcli (except if empty).

scloglevel

Log verbosity for sc2mpd.

scplaymethod

sc2mpd play method (mpd/alsa). With this set as 'alsa', sc2mpd will send the audio directly to the sound driver, which is the only way to really avoid skips and control the synchronization in multi-room setups. For 'alsa', make sure that user upmpdcli has permission to access the audio devices !

schttpport

Port used by sc2mpd for MPD to connect to. Used only for scplaymethod=mpd. sc2mpd only accepts connections from localhost.

scalsadevice

Alsa device used by sc2mpd for playing audio. Only used for scplaymethod=alsa. Use 'aplay -L' to see the possible values.

sccvttype

sc2mpd resampling method. Only used for scplaymethod=alsa. sc2mpd uses libsamplerate. The default method is SRC_SINC_FASTEST and a Rasberry Pi 1 is fast enough to use it. Possible values: SRC_SINC_BEST_QUALITY, SRC_SINC_MEDIUM_QUALITY, SRC_SINC_FASTEST, SRC_ZERO_ORDER_HOLD, SRC_LINEAR. See the libsamplerate documentation for descriptions. Anything above SRC_SINC_FASTEST needs a serious CPU. BEST_QUALITY uses approx 25% cpu on a core i7 4770T. Obviously too much, actually might not be sustainable (it’s almost 100% of 1 cpu). MEDIUM_QUALITY is around 10% on the same machine, FASTEST is 4-5%. Given that this is measured for the full process, probably a couple % for the conversion in fact. NONE will turn resampling off: minimum CPU and best quality, but guaranteed glitches from time to time, depending on the clocks skew.

scusempdvolume

Scale songcast stream based on mpd volume value Allow controlling the volume from the Control Point by scaling the stream according to the mpd volume value. Only works when scplaymethod is 'alsa'.

sc2mpd

Path to sc2mpd. Only useful if it is not in /usr/bin and the location is not in the $PATH for the init scripts.

screceiverstatefile

Path to a screceiver state file. If set, the sender uri and metadata will be read from the file when initializing the Songcast Receiver service and written to the file when a Sender is set for the service. Useful for preserving the sender information between restarts.

Songcast Sender parameters

scstreamcodec

!!Standard Songcast receivers only support PCM!! Codec to use for the network stream. Set to empty or PCM to support foreign receivers. Or use FLAC or OPUS for lower network load.

scsenderpath

Path to starter script This is normally scmakempdsender which starts the auxiliary mpd and the sender process. Empty and searched in the PATH by default.

scstreamscaled

Scale the Songcast stream. If set, MPD software volume control will be applied to the stream. True by default: using a Control Point to set the volume on the upmpdcli instance which started the Sender affects the volume for all Receivers.

scsendermpdport

localhost port to be used by the auxiliary mpd.

scripts_dir

External sources script directory. Location for the scripts used to set up additional external sources. See the Songcast Sender support documentation page.

scscriptgracesecs

Grace period to wait for a script process to exit before it is forcely killed. In seconds. Default 2 S.

Installation from packages

The upmpdcli downloads page has a number of pointers to binary packages for a number of common distributions (Debian, Raspbian, Ubuntu, Fedora) and architectures (ARM and x86).

Building from source

Building upmpdcli on Linux

For building from source, you will need a C++ compiler with full C++11 support, and the development packages for the supporting libraries: libcurl, libmicrohttpd, libmpdclient, and libexpat.

Also the Python modules for streaming service support use the python-requests package, so you may need to install it (it is only needed at run time).

If you are using the source from the git repository, you will also need the autoconf, automake, libtool trio. Use the autogen.sh script to set things up.

So you need to either clone 3 git repositories:

or download the release tar files from the the upmpdcli download page

For upmpdcli, there are two specific configure options. Each needs the installation of additional dependancies:

  • --enable-confgui: build the configuration editor GUI. This will need the Qt development packages

  • -disable-spotify: do not include build the Spotify access module. This used to be disabled by default, but is now enabled because it does not create a build dependancy, as the interface include file is bundled, and the library itself is dynamically opened at run time, not linked. Of course, the library will need to be installed on the target machine for the Spotify access to work. Currently, the easiest way to obtain it is from the Mopidy repository.

Once the source is extracted, the procedure is standard for each of the three packages:

# Only for git source
sh autogen.sh
./configure --prefix=/usr --sysconfdir=/etc [other options]
make
sudo make install

Which you should apply first to the libnpupnp source, then to libupnpp, then to upmpdcli.

If you omit the --sysconfdir=/etc part, upmpdcli.conf will end up in /usr/etc/, which is ok, but confusing, as package installers put it in /etc/

Boot time startup

upmpdcli will try to change its uid to user upmpdcli if it is started by root. It will refuse to run if the user does not exist.

If started by root, upmpdcli will also write its process id to /var/run/upmpdcli.pid.

There are boot-time startup scripts in the debian/ directory inside the source tree (for Debian/Ubuntu/Mint/Raspbian etc.). There is also a systemd service file under systemd/ (for Fedora et al.).

The boot scripts are installed by the pre-built packages, so will just have to edit the configuration file after installing them, all the rest should just work.

Building libupnpp and upmpdcli on Mac OS X

I don’t run Mac OS X and I can’t support this directly. However a kind user has provided a build recipe based on homebrew.

You will first need to apply the patches from this file.

Then:

brew install mpd
brew install autoconf
brew install automake
brew install libtool
brew install libupnp libmpdclient expat jsoncpp libmicrohttpd expat curl
brew install pkg-config
brew install expat
export PKG_CONFIG_PATH=/usr/local/opt/expat/lib/pkgconfig
configure --prefix=/usr
make

Building OpenHome and sc2mpd

There are two parts in building sc2mpd:

  • Building the Openhome libraries

  • Building sc2mpd proper

First download a sc2mpd release or clone the sc2mpd Git repository.

Creating the the OpenHome source tree

Building the Openhome libraries is a bit of a black art for a number of reasons:

  • There are no released distributions for the OpenHome libraries, but only a number of git repositories for the different components. The state of the repositories is not completely consistent at all times (there will be moments when a component will not build with another).

  • The OpenHome build system is very complicated because it works on multiple platforms and multiple language bindings.

The first step is to create the openhome source tree. There are two possible ways, described just below.

In both cases, after creating the tree, you need to compile the openhome software. See the sc2mpd build section below.

OpenHome source tree, the easy way

Download the tar file of the appropriately patched openhome code from the upmpdcli downloads page (use the current one, the date on the one below is just an example), create an empty directory, untar it in it

cd /home/me
mkdir openhome
cd openhome
tar xf /path/to/openhome-sc2-20210305.tar.gz
OpenHome source tree, the complicated way

The sc2mpd source comes with a shell script named ohbuild.sh to help with this. It has several functions:

  • Cloning the OpenHome and checking out verified revisions

  • Applying a few minor patches to ensure that the build will work in a simplified environment (e.g. without a c# compiler).

  • Creating a tar file of a compact trimmed tree.

  • Running the build either from the cloned tree or the tar file.

The tar functions are mostly useful to help with building packages. For a normal build, the procedure would be as follows:

cd sc2mpd
mkdir /my/place/for/openhome
sh ohbuild.sh -b /my/place/for/openhome
Note
for sc2mpd 1.1.7 you will need to copy the ohpatches directory from the git code directory to the extracted tar file directory because I forgot to include it in the distribution.

Building sc2mpd

sc2mpd depends on a number of libraries, which are usually packaged on Linux, and which you need to install first:

  • The microhttpd library. Install the development and runtime packages which are currently named libmicrohttpd-dev and libmicrohttpd10 on Debian-derived systems (use libmicrohttpd and libmicrohttpd-devel for Fedora).

  • The libsamplerate library (libsamplerate0 on Debian, libsamplerate-devel for Fedora).

  • The libasound Alsa interface library (libasound2-dev on Debian, alsa-lib-devel for Fedora).

First build openhome. Change your current directory to the top of the sc2mpd source tree, then run:

sh ohbuild.sh /my/place/for/openhome

Once OpenHome is built and the auxiliary library development packages are installed, build sc2mpd, using the following commands inside the sc2mpd directory (you only need the autogen part for a cloned git tree, not for a tar extraction):

sh autogen.sh
./configure --prefix=/usr --with-openhome=/my/place/for/openhome
make
sudo make install

The build uses static Openhome libraries, so you can move the executable to another machine without needing the Openhome directory (don’t forget to install the libmicrohttpd, libsamplerate and libasound runtimes though).

After restarting upmpdcli, it should advertise the Receiver service and appear in the Songcast Sender menus.

Building a Debian package from an sc2mpd tar distribution

Here follows a synopsis of building a debian package for an sc2mpd tar distribution. You’ll need to replace the 1.1.1 and 20151223 versions with whatever you are building. Note that the 1.1.1 value must match what you have in the Debian changelog (or update the changelog).

The $distdir and $sc2mpd_src values stand for places where you store the tar files and the sc2mpd (git) source tree.

mkdir sc2mpd_build
cd sc2mpd_build
cp $distdir/sc2mpd-1.1.1.tar.gz sc2mpd_1.1.1.orig.tar.gz
cp $distdir/openhome-sc2-20180615.tar.gz sc2mpd_1.1.1.orig-openhome.tar.gz
tar xzf sc2mpd_1.1.1.orig.tar.gz
cp -rp $sc2mpd_src/debian sc2mpd-1.1.1/
cd sc2mpd-1.1.1
mkdir openhome
cd openhome
tar xzf ../../sc2mpd_1.1.1.orig-openhome.tar.gz
cd ..
debuild

Annex: setting up Spotify access authorization

Upmpdcli uses a hybrid approach for accessing Spotify: it uses the newer WEB API for browsing the catalog, and the old libspotify library for streaming.

As a consequence, two sets of authorization parameters must be specified: the library uses a classical user name ` password pair, to be set in the configuration file.

The WEB API uses a more modern (and more ennoying) oauth2 authentification/authorization method. This needs to go through a WEB browser. You will need to execute the following steps to set things up:

  • Download the zip file for the helper script. Right-click the link and use Save link as.

  • Unzip the file on any Linux machine with a web browser. This will create a 'upmpdcli-spotify-authinit' directory. The chosen machine can be the host where upmpdcli runs, or not: any Linux machine with a browser will do.

  • Check that the python3-requests package is available on the chosen host, or install it.

  • Run the helper script inside the unzipped directory. Replace 'username' with your Spotify user id.

    ./spotiauthinit.py username
  • The script will start a Web browser, and you will be asked to log in to Spotify and authorize upmpdcli to access your data.

  • At the end of the web interaction, you will be redirected to a non-existing page (an error will be displayed in the browser). Copy the link address from the address bar, and paste it to the spotiauthinit.py input line (you will have been prompted to do this by the script).

  • The script will then store the authorization token in a file named '/tmp/spotipy-<username>-token', which you will need to copy to the host where upmpdcli run, and move it to a file named '/var/cache/upmpdcli/spotify/token', or, if you changed the value of the cachedir parameter, to '[cachedir]/spotify/token'.

  • Make sure that /var/cache/upmpdcli and its contents belong to upmpdcli:

    sudo chown -R upmpdcli /var/cache/upmpdcli/spotify

Annex: Songcast installation walkthrough

If you want to play from a Mac or Windows machine, install the Songcast application

Note
Not all Songcast capture application versions work well with upmpdcli. Lately (03-2017), the latest version (4.8.535) seems to work fine. In the past, I’ve had good luck with 4.4.190 but not with the 4.5 ones (it is possible to get them to work with upmpdcli from the upplay control panel, but the Windows app claims that the upmpdcli receiver is unavailable.).

I could not get IP multicast to work with WIFI Receivers (the sound drops constantly).

There are well-known problems with multicast and WIFI (see for example this superuser.com question for detailed explanations). This seems to be dependant on the WIFI hardware (router/access points) used, so maybe you will have more luck than me.

If some of your Receivers use WIFI, and you experience sound issues, check that "Unicast" is selected in the Songcast configuration "advanced" panel on the desktop.

Under most conditions, WIFI data rates should be more than sufficient to transport Songcast streams (a bit over 1 Mbit/S for 48k/24bits, 700 Kbits/S for 44.1k/16 bits).

However, Songcast is probably best transported over a wired connection. If you are doing this over WIFI and experiencing glitches, the wireless is the first suspect.

If the Sender is a upmpdcli host, you should probably also install the upplay Control Point somewhere. Recent upplay versions include a tool to control Sender and Receiver instances. This is less necessary if the Sender is on Windows or Mac, as the Songcast application on these platforms includes a limited connection tool (no multiroom).

Download and install the upmpdcli and sc2mpd packages for your Linux system. See the download page here.

When using a single Receiver, things should just work, the UpMpd Receiver should appear in the Songcast app on the host (or in the upplay control panel).

Warning
There is no software volume control for the upmpdcli Songcast Receivers for now: use either a local mixer or the little round things on the pre-amps. Set the volume low when experimenting !
Note
The receiver side does not work too well on Raspberry Pis using an USB DAC (as far as I could see). The reason may be that the data rate of the uncompressed stream is just too much for the poor Pi Ethernet/USB chip. Things work just fine with an I2S DAC (or on HDMI probably). When on WIFI, the results are sometimes irregular too, depending on the quality of the connection. If you have no Ethernet cabling, Ethernet over power lines may work better than WIFI. The best combination of network and DAC link is definitely Wired and I2S (or HDMI).

When using multiple Receiver instances, you need to at least customize their names, and you want to take care of synchronization issues. You will need to take a look at a bit more documentation:

Annex: Setting up external audio sources for the Songcast Sender

The upmpdcli Sender modes are controlled by switching OpenHome Sources. By default, and if the sc2mpd package is installed, upmpdcli will create 'PL-to-Songcast' and 'RD-to-Songcast' sources for broadcasting its playlist or radio streams to Songcast.

As explained in the main body, there is nothing magical with this: mpd just streams to a FIFO which is read by the mpd2sc command, which then broadcasts it. This pipe is set up by a script (scmakempdsender).

Under certain conditions, if upmpdcli finds other scripts in a designated directory, it will create more sources, and start them when the corresponding source is selected (of course, it expects the script to create a Songcast Sender pipe).

The upmpdcli source comes with a sample script which sets things up for mpd2sc to read arecord output, allowing multiroom playing of an external analog source (line-in). The sample script is flexible enough to manage different inputs without code changes, and there are comments at the top which give detailed explanations. The parts of more general interest will be a bit expanded here (see below). If you want to use the script itself, you need to look at the comments. You will find the script under 'samplescripts/Analog-Input' in the source tree.

Based on the same mechanism (but quite different code inside the script) there is also a nice HOWTO explaining how to link a Bluetooth device to Songcast.

The general idea is that upmpdcli will create an Openhome Source for each script it finds inside a designated directory. By default, the directory is /usr/share/upmpdcli/src_scripts, but it can be changed by setting the ohsrc_scripts_dir configuration variable inside /etc/upmpdcli.conf

For managing analog sources, entries inside the directory will typically be created as symbolic links to the sample script, which is installed as /usr/share/upmpdcli/Analog-Input. For doing other things, the scripts will not be links, but they must still be named a bit specially.

The scripts (or links) must be named like SourceType-SourceName, where SourceType MUST BE one of Analog, Digital, or Hdmi, (which are all the same, and for display purpose only), and you can choose SourceName as you wish, but it should contain no space characters.

The Source will appear with type Analog, Digital or Hdmi and name SourceName in an OpenHome Source select dialog (e.g from upplay).

The Analog-Input sample script has provisions for reading the device name and setup/teardown instructions from external files, so that it does not need to be modified. This is only relevant for the sample, please have a look at the comments for details.

Annex: the radio scripts

The radio URL script

The url field inside the radio definition can be a direct audio link or a link to the radio station playlist. This link will be interpreted by the 'fetchstream.py' ('rdpltostream' directory inside the source tree, or see '/usr/share/upmpdcli/rdpl2stream'). The Python code knows about the various playlist formats used by the stations.

The dynamic album art script

If set, artScript is the path to an executable script which can retrieve the image URL for the currently playing title. It can also be a simple script name if this is located in the PATH or in the 'radio_scripts' directory inside the upmpdcli directory (typically '/usr/share/upmpdcli').

Some radios (e.g. Radio Paradise) publish the album art for the currently playing title. The details vary. The artScript parameter, if set, should point to an executable script which prints this dynamic art Uri to stdout. The image will supercede the radio logo, to be displayed by control points. Beware that the path to the script must be accessible by the upmpdcli user, which may not be the case for your home. /usr/local/bin is your friend. The Upmpdcli installation has a very small set of scripts inside the '/usr/share/upmpdcli/radio_scripts' directory. This includes a very rough example for retrieving the Radio Paradise art URI, 'radio-paradise-get-art.sh'

The art script is executed each time the stream metadata changes (the data is obtained by mpd from Icy metadata in the stream).

Upmpdcli does not set a timeout for the artScript execution. A reasonable value should be used inside the script, to avoid freezing upmpdcli forever.

There is no reason to have an artScript if metaScript exists for the radio. metaScript can also return the image URL.

The dynamic metadata script

If set, metaScript is the path to an executable script which can retrieve the metadata (possibly including art Url) for the currently playing title. It can also be a simple script name if this is located in the PATH or in the 'radio_scripts' directory inside the upmpdcli directory (typically '/usr/share/upmpdcli').

The script should output the metadata in JSON format. An example output follows (the newlines and whitespace are just here for readability, any valid JSON will do):

{
    "title" : "The title of the current track",
    "artist" : "The artist playing",
    "album": "The album name",
    "artUrl" : "https://www.somesite.com/path/to/image.jpg",
    "audioUrl" : "http://some url",
    "reload" : 103
}

The reload value gives the number of seconds after which the script should be re-executed (the clever radio sets this to the remaining song time). By default, the script is executed every 10 S.

Any value not present will simply not be used (not an error). audioUrl is generally not set. If it is set, it’s the next audio Url to queue after the current one (this is used for radio streams which are a sequences of URLs rather than a continuous stream, for example the Radio Paradise FLAC station).

The 'radio_scripts' directory has two examples of radio metadata scripts, a simple one ('fip-meta.py'), and a quite complicated one ('radio-paradise-get-flac.py'). Both need the Python3 'requests' package to be installed.

Annex: command line and environment

In most situations, upmpdcli will be run as follows:

upmpdcli -D -c /etc/upmpdcli.conf

The -D option tells upmpdcli to fork and run in background. The -c option specifies a configuration file.

See the upmpdcli(1) manual page for more information about the command line.

Some of the essential configuration parameters can be set from the command line, a configuration file, or the environment in this order of priority. It would be rather confusing to use a mix of methods, so you should probably chose one.

All parameters have defaults, and a minimal installation will need no customisation at all.

What

Command line

Environment

Config variable

Configuration file name

-c config

$UPMPD_CONFIG

Host name or IP address where MPD runs

-h mpdhost

$UPMPD_HOST

mpdhost

TCP port for MPD

-p mpdport

$UPMPD_PORT

mpdport

UPnP "friendly name" for the device. This gets displayed in network search results.

-f friendlyname

$UPMPD_FRIENDLYNAME

friendlyname

Log file name. Leave empty for stderr

-d logfilename

logfilename

Verbosity level (0-4)

-l loglevel

loglevel

UPnP network interface

-i iface

$UPMPD_UPNPIFACE

upnpiface

UPnP port

-P port

$UPMPD_UPNPPORT

upnpport

Annex: the upmpdcli-config GUI configuration editor.

The upmdpcli-config tool presents a graphical interface for creating an upmpdcli configuration file. It presents different tabs with controls, directly matching the organisation of the parameters in the documentation. Both the tool and the manual are generated from data in the reference configuration distributed with the package (typically '/usr/share/upmpdcli/upmpdcli.conf-xml').

You can use the tool to create a configuration from scratch (just tweak what you want, then save the file), or for editing an existing configuration. The latter can be done either by passing the configuration file name on the command line, or by using the 'Open' menu entry. If you use the command line, the parameter automatically becomes the target of a future 'Save' command (you can change it by using 'Save as'). When using 'Open', you will be asked to choose an output destination when saving.

Each control has a label, and an longer explanation in a tooltip, which you can see by leaving the cursor on the label.

Once you are satisfied with the changes, you can save the file, and move it to its normal location if needed (e.g. '/etc/upmpdcli.conf').

Only the parameters which were changed in the configuration you edit (if not starting from scratched), and those which you change through the interface, will be saved to the output. Parameters unchanged from the defaults will not appear at all, allowing for a less cluttered file.

Annex: the scweb Songcast control interface.

This is only useful if you have no machine on which to run upplay, or Bubble DS Next. Either are easier to use than the web tool.

To avoid having to access the command line interface to control the Songcast groups, upmpdcli comes with a small Web server which uses scctl to actually do the work. This is found inside the web/ subdirectory inside the upmpdcli source tree.

The server is based on the Bottle Python Web Framework and it only depends on Python 3.

You can use the scweb-standalone.py script to manually start the interface:

python3 ./scweb-standalone.py

This will start a server on localhost, on port 8680 by default which is good for testing, but not very useful. Use the -a 0.0.0.0 option to let the server answer on all local addresses (or specify the address to use a specific interface):

python3 ./scweb-standalone.py -a 0.0.0.0

-p can be used to specify a port.

Once started, connecting to the server from any browser should hopefully display a reasonably self-explanatory interface.

Recent upmpdcli packages install the web app as a service named scweb. The service is not started by default though, you need to edit /etc/default/scweb.

Annex: building openssl for Debian Jessie

The OHCredentials service needs OpenSSL 1.1 but Debian Jessie only has 1.0. The following recipee builds a static version of the openssl command, which is installed with a specific name (upmpdcli-openssl). No libraries are installed and the standard command is left undisturbed, so that there is no risk of damaging the system.

Note that I am making no claims about the security of the encryption provided by this method. This should be fairly sufficient for a Tidal password going around your local network though (except maybe if you think that the NSA is interested in your playlists).

sudo apt install git make gcc
cd
git clone https://github.com/openssl/openssl.git
cd openssl
git checkout -b origin/OpenSSL_1_1_0-stable
./config
make
cc -o upmpdcli-openssl apps/*.o  apps/libapps.a libssl.a libcrypto.a -ldl -lpthread
sudo cp upmpdcli-openssl /usr/bin

Then edit '/etc/upmpdcli.conf' and add the following:

opensslcmd = /usr/bin/upmpdcli-openssl

We chose to copy the command to '/usr/bin', but this could be any place. Change the path in '/etc/upmpdcli.conf' in this case.

Restart upmpdcli, and the logins from Kazoo should work.