Transcoding Live TV to Android

[bgowland]

Sorry, it's difficult to advise particularly because TV broadcast standards vary around the world. I've only got experience of UK SD broadcasts and I've been able to use MX PLayer with SW decoding and also with the lower resolution / bitrate transcoding options. Playing back the rolling buffer files created by npvr for live tv is always going to add an extra layer of complexity.

As I said, I'll hopefully have a live feed rigged up again tonight so I'll do some testing and see what happens.

Cheers,
Brian

[JavaWiz]

I use XBMC for android with the NPVR plugin. Works great for me, although I must admit I don't watch a lot of live TV on my android.

[t^2]

Sorry, it's difficult to advise particularly because TV broadcast standards vary around the world. I've only got experience of UK SD broadcasts and I've been able to use MX PLayer with SW decoding and also with the lower resolution / bitrate transcoding options. Playing back the rolling buffer files created by npvr for live tv is always going to add an extra layer of complexity.

As I said, I'll hopefully have a live feed rigged up again tonight so I'll do some testing and see what happens.

Cheers,
Brian

Any news?

[bgowland]

Any news?

Unfortunately no, not yet. I can't get a lock on any signal - not really sure what' has gone wrong.

[bgowland]

Well now my main aerial is magically picking up signals again, I've done a few tests with different channels and different transcode presets.

All of the channels I receive are DVB-T SD although some have a slightly higher resolution and bitrate than others. Using my Nexus 7 (7in 1280x800) and MX Player with SW decoding selected, I tried 2 BBC channels (normally having the higher res/bitrate) and 2 ITV channels (normally slightly lower).

I can't get the High 1600K preset to work at all on any channel. The High 1200K preset works for some channels but in all cases quickly goes into a freeze-play-freeze-play... cycle - this was also true for the Med 800K and 600K for ITV channels although the freeze/play behaviour took longer to happen. The BBC channels did seem quite happy with the Med 600K preset though. The only way I could get ITV channels to transcode smoothly was to use Low 400K although there was notable picture imperfections (occasional slight fuzziness or slight blurring) - the BBC channels looked awful at Low 400K (extremely blocky and blurred colours). I didn't bother at all with Low 250K as I know it's virtually unusable on most devices.

That's all I can tell you really - it's really hit or miss. It is possible that tweaking the ffmpeg command-line parameters in config.xml might help with different broadcast standards and their stream codecs. I did ask sub if it would be possible to have multiple ffmpeg 'profiles' in the config.xml and he was OK with that idea but the option didn't make it to the current npvr release and he told me to chase him on the subject.

Cheers,
Brian

[t^2]

Well now my main aerial is magically picking up signals again, I've done a few tests with different channels and different transcode presets.

All of the channels I receive are DVB-T SD although some have a slightly higher resolution and bitrate than others. Using my Nexus 7 (7in 1280x800) and MX Player with SW decoding selected, I tried 2 BBC channels (normally having the higher res/bitrate) and 2 ITV channels (normally slightly lower).

I can't get the High 1600K preset to work at all on any channel. The High 1200K preset works for some channels but in all cases quickly goes into a freeze-play-freeze-play... cycle - this was also true for the Med 800K and 600K for ITV channels although the freeze/play behaviour took longer to happen. The BBC channels did seem quite happy with the Med 600K preset though. The only way I could get ITV channels to transcode smoothly was to use Low 400K although there was notable picture imperfections (occasional slight fuzziness or slight blurring) - the BBC channels looked awful at Low 400K (extremely blocky and blurred colours). I didn't bother at all with Low 250K as I know it's virtually unusable on most devices.

That's all I can tell you really - it's really hit or miss. It is possible that tweaking the ffmpeg command-line parameters in config.xml might help with different broadcast standards and their stream codecs. I did ask sub if it would be possible to have multiple ffmpeg 'profiles' in the config.xml and he was OK with that idea but the option didn't make it to the current npvr release and he told me to chase him on the subject.

Cheers,
Brian

No transcode setting works for me on any channel. The only thing that works is no transcoding. However, something else has changed (believe a MXplayer update) and I can no longer get audio to work with MXplayer. I can get sound to play in BSPlayer with the video but no matter how I set up BSplayer it doesn't playback video as smoothly as MXplayer. If I could at least get MXplayer to play (with audio) the non-transcoded stream then that would be usuable at least.

Don't know if this is useful info for you, but I can tell you that Media Browser (using the Media Browser Android app) transcodes perfectly to my Galaxy SIII.

[t^2]

Just for the fun of it I used NPVR on my HTPC to serve un-transcoded live TV to VLC (set http://localhost:8866/live?channel=88 as the input for VLC's stream) and used VLC to transcode it out to port 8080. I used MXplayer to play it on my Android Galaxy SIII. VLC transcoded it no problem and MXplayer played it no problem. All bit rate and resolution combinations that I tried worked fine (fps was left to source). Wonder what's up with nDroid that it can't get-r-done?

[mvallevand]

Just for the fun of it I used NPVR on my HTPC to serve un-transcoded live TV to VLC (set http://localhost:8866/live?channel=88 as the input for VLC's stream) and used VLC to transcode it out to port 8080. I used MXplayer to play it on my Android Galaxy SIII. VLC transcoded it no problem and MXplayer played it no problem. All bit rate and resolution combinations that I tried worked fine (fps was left to source). Wonder what's up with nDroid that it can't get-r-done?

This makes sense to me. VLC does more than just transcode, it provides a buffering and transcoding http streaming server. Also the ffmpeg that comes with NextPVR is obsolete and someone is going to need to take the effort to come up with good transcoding command line options and most users don't bother to tune it for their broadcast streams.

I use VLC quite successfully with X-NEWA and suggested that Brian try it too. The NEWA interface is moving to JSON which will make VLC easier to implement for other apps.

Martin

[t^2]

So this means what in general? Basically nDroid (or anything else NPVR related) can not transcode live TV now (an perhaps for the foreseeable future)? What is JSON?

[t^2]

Well now my main aerial is magically picking up signals again, I've done a few tests with different channels and different transcode presets.

All of the channels I receive are DVB-T SD although some have a slightly higher resolution and bitrate than others. Using my Nexus 7 (7in 1280x800) and MX Player with SW decoding selected, I tried 2 BBC channels (normally having the higher res/bitrate) and 2 ITV channels (normally slightly lower).

I can't get the High 1600K preset to work at all on any channel. The High 1200K preset works for some channels but in all cases quickly goes into a freeze-play-freeze-play... cycle - this was also true for the Med 800K and 600K for ITV channels although the freeze/play behaviour took longer to happen. The BBC channels did seem quite happy with the Med 600K preset though. The only way I could get ITV channels to transcode smoothly was to use Low 400K although there was notable picture imperfections (occasional slight fuzziness or slight blurring) - the BBC channels looked awful at Low 400K (extremely blocky and blurred colours). I didn't bother at all with Low 250K as I know it's virtually unusable on most devices.

That's all I can tell you really - it's really hit or miss. It is possible that tweaking the ffmpeg command-line parameters in config.xml might help with different broadcast standards and their stream codecs. I did ask sub if it would be possible to have multiple ffmpeg 'profiles' in the config.xml and he was OK with that idea but the option didn't make it to the current npvr release and he told me to chase him on the subject.

Cheers,
Brian

Anyway, for what it's worth, I finally got NPVR to transcode live TV to my device (Android/Galaxy SIII). However, success wasn't accomplished with nDroid. I had to do it via a convoluted route in NEWA. The steps I took are noted here.

So NVPR does appear to have the core functionality to do this task. It would be nice if a nice GUI/app front end (like nDroid) could take care of the mechanics of getting it done.