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By looking more closely to the transcoding process, I understood that it seems to be a header/url conversion only, by default for mp3 streams. So I tried to force some sort of actual stream conversion. To do so I installed the avconv package and tried to experiment with the settings.

Since I could not find a way to force the transcoding from mp3 to mp3, I tried with the transcoding of an aac radio stream converted to mp3 to the car player. (of course this setup does work ok with windows Media player)

To do so, I created a 'Test aac.m3u' playlist:
#EXTM3U
#EXTINF:300,[T3;mp3] Test AAC
http://air.radiorecord.ru:80/rr_aac

I updated the stream/converter field with avconv and the stream.transcode with aac:mp3

From the attached debug log, I can see that everything seems to maybe start ok, but i am wondering if the beginning of the transfer process could be incomplete before the timeout (timeout has value '2000') and closed too early. Is there a way to experiment this with some greater values for some of of the timeout options ?

Thanks

-Michel
Did any music play when you did this?
Yes for both attempts from today, the local mp3 files did played ok.

But no luck with the radio streams...
(07-01-2016 17:50)Michel Lopez Wrote: [ -> ]I restarted my testing with a basic configuration, storing 2 mp3 files and this updated playlist directly to the root folder of the shared folder. Then I manually forced a re-scan, and shut down the device, before moving to the garage to restart everything, in the car environment.

This time all the entries are properly detected and displayed. Since the car player does auto start playing, it always start playing one of the music file as soon the UPnP server is properly detected & enabled. I then have been able to navigate to the other entries and of course tried to get to the radio stream. The radio does not work and the entry become grayed out, and not available. Of course when the radio stream has failed, the player automatically goes back to playing music.

Just in case I also retried after setting some value to delayHLS, but with no change. Both trace files are attached.

Thanks.

-Michel

This trace log is very helpful. Some interesting points from the first log:

1) The first request to play the radio stream is at 07:08:09. Contacting the remote stream takes 12 seconds (a very long time).

2) The second request to play the radio stream is at 07:09:07. Contacting the remote stream takes 36 seconds (an extremely long time).

3) The third request to play the radio stream is at 07:09:43.133, while the second request is still being processed and before MinimServer has sent a response to the second request.

4) The renderer cancels the third request at 07:09:43.773. The trace log shows that a timing bug in MinimStreamer caused the output stream for the second request to be corrupted when the third request was cancelled. I don't think it is safe to draw any conclusions from what happens after this corruption has occurred. This bug willl be fixed in the next release of MinimStreamer.

5) While 1) to 4) above are happening, there is continuous activity related to streaming the file "Axel Bauer - Cargo.mp3"

The second log is simpler. There is only one request for the radio stream and it takes 8 seconds to contact the remote stream. The radio stream data is streamed successfully for about 1 second before the renderer closes the connection. There is no corruption of the radio stream and it isn't clear why the renderer closed the connection. The delayHLS change that you made for this test run doesn't have any effect on the non-HLS radio station that you are using for testing.

I don't think it is useful to transcode AAC to MP3. The log for this shows some AAC errors from avconv and these might be related to the subsequent problems. I don't see any problems in this log related to the timeout=2000 setting. I would like to focus on the simplest case of getting an MP3 radio stream to play without any transcoding.

I have installed Audi MMI Connect on my Android tablet. The MMI Connect UPnP server seems to stay active for only about a minute after I launch MMI Connect for the first time. By capturing some debug information during this short window, I see that the following DIDL-Lite metadata values for radio streams in MMI Connect are different from what MinimStreamer is producing:

size="500000000" duration="05:00:00.000" bitrate="the-stream-bitrate"

MinimServer/MinimStreamer doesn't have any way to get the bitrate and I don't think this value is important for playing the stream.

It would be possible for MinimServer/MinimStreamer to send the above values for size and duration. These values might be important for playing the radio stream. I will produce a test build that does this and send you a PM with instructions on how to install it.
Thanks a lot for looking into this.

About the timing issues, those could be related to the network being 'only' 3G with this type of on-board car device. That said, the reception in my garage in very weak, so that could explain the 'extremely long time'. But for this type of 'in moving car' configuration the variation of the network quality is expected.

About the constant audio activity that you saw, if you try to connect to the Audi MMI app, with, for example, Windows Media Player (yes this does work perfectly and will remove the one minute issue), you will see that they have somehow tweaked the starting steps of the streaming process, so that there is a special default music with a voice message saying 'the data communication is established' that is played until the actual stream starts.

Thanks again for looking into this. Please do let me know what I can do to help.

-Michel
(08-01-2016 19:07)Michel Lopez Wrote: [ -> ]About the constant audio activity that you saw, if you try to connect to the Audi MMI app, with, for example, Windows Media Player (yes this does work perfectly and will remove the one minute issue), you will see that they have somehow tweaked the starting steps of the streaming process, so that there is a special default music with a voice message saying 'the data communication is established' that is played until the actual stream starts.

I wasn't able to make this work. WMP didn't show any music or radio stations in the MMI connect library and the UPnP server disappeared after a couple of minutes.

How do I add music to the MMI connect library on my tablet? How do I get WMP to show this added music and the favourite radio stations that I have saved in MMI connect?
I gave up using this app on my (very old) Android tablet, as it is crashing a lot. To debug this, I am using this app on an old unused Iphone 4, without a SIM card. As usual when both the phone and the PC are connected to the same network, nothing is needed to get the Audi MMI to show up in the list of Windows Media Player. The 1 minute timeout is also present on the Iphone app and can only be addressed (from my findings) by getting some renderer/control point connected before this timeout.

In some case Windows Media Player does not seems to be able to browse the full content list provided by this app, to address this you need to go to the radio tab in the Audi App and set to favorite some radio entries. By doing this you will be able to browse them easily from Windows Media Player.

I also got good results to look into the details of the streams with the AV Media Controller application included in the former Intel UPnP developer tools available from http://opentools.homeip.net/dev-tools-for-upnp
[attachment=1062] [attachment=1063] [attachment=1064]
(08-01-2016 20:20)Michel Lopez Wrote: [ -> ]I gave up using this app on my (very old) Android tablet, as it is crashing a lot. To debug this, I am using this app on an old unused Iphone 4, without a SIM card. As usual when both the phone and the PC are connected to the same network, nothing is needed to get the Audi MMI to show up in the list of Windows Media Player. The 1 minute timeout is also present on the Iphone app and can only be addressed (from my findings) by getting some renderer/control point connected before this timeout.

In some case Windows Media Player does not seems to be able to browse the full content list provided by this app, to address this you need to go to the radio tab in the Audi App and set to favorite some radio entries. By doing this you will be able to browse them easily from Windows Media Player.

I also got good results to look into the details of the streams with the AV Media Controller application included in the former Intel UPnP developer tools available from http://opentools.homeip.net/dev-tools-for-upnp

Thanks for this. Using AV Media Controller, I can see some local music under MMI on my Android tablet. I can't see any internet radio stations. Under Internet Radio, all I see is "No internet connection" (or something like that, as the UPnP server has now disappeared and I can't check the exact wording). I have saved a favourite station but this isn't visible.

In the MMI app UI, I can see radio stations but I can't see any local music. There is something called Media centre that shows a WiFi symbol with no music content.

I see the MMI server in WMP but there is no content underneath it. Having WMP and/or AV Media Controller connected doesn't prevent the UPnP server from disappearing.

What exactly do you do after starting WMP to make it connect to the MMI server and view content underneath it?

I don't have an iPhone. I have an iPad but MMI isn't available for iPad. I have an iPod touch but it is limited to iOS 6.1.6 and MMI requires iOS 9.
I have not been that far with the Android version of the app, for quite some time, so I am not sure. Because it is always crashing, almost at launch, since the last Android system update, I can't repro.

I know that this app is designed both to share a list of worldwide radios streams and the local audio files. I never actually looked into the music sharing aspect of this app, but have already seen that it detect and share automatically the supported music files available in the usual system folder, without any configuration option or management menu. I think that the list of radio streams is pulled from some internet servers and is not stored in the app. Maybe with some sort of cache, but with a network trace I clearly see the request at every launch of this app. I am still trying to find a way to capture the same raw traffic with the car setup.

I am surprised when you said "MMI isn't available for iPad" as I do have installed this app on my Ipad and it is working perfectly fine on it. Of course it is an app designed for Iphone, but both from my French and US App Store accounts, nothing is preventing this app installation on Ipad. (Maybe you could try, on your Ipad, this direct link https://itunes.apple.com/gb/app/mmi-connect/id570608111 as it says 'Compatibility: Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch').

When starting this app on either an Iphone or an Ipad, selecting "Demo mode" and then one of the demo car from the list will let you go to the Internet Radio tab. When done, in Windows Media Player the UPnP server will appear in the list and you just need to select it to browse the content by going to the music node.

[attachment=1066]

The 1 minute timeout still apply, but if you are able to start playing one of the stream, the UPnP server should not disappear for a few minutes longer.
Thanks for this. I used the URL that you posted to install MMI connect on my iPad (the App Store won't let me do that) and I can now see internet radio stations in WMP. However, the UPnP server still switched off after a minute or two even though WMP was playing music from a radio station when this happened. What is the simplest way to restart the UPnP server?
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