Tvheadend

Goncalo Luiz wrote:

Hi,

I am considering going for a setup like this:

- Two USB DVB-2 tuners
- 1 Raspberry pi 3

The goal is to connect my Freeview dish to the tuners and use the pi to serve as a tvheadend backend, transcoding the selected channels to a number of LAN/WAN frontend players. The frontend would connect to the tvheadend backend, select a channel and if a tuner is available, the server would send the transcoded stream.

Before I go ahead and buy the components, I'd like to get some validation from the community this setup can work. I am particularly unsure if the Raspberry Pi 3 would be powerful enough to decode and transcode two DVB-2 (HD) streams simultaneously. I guess the Pi GPU could provide assistance on this (so long the licenses are enabled, which I would be able to do), but have no idea whether tvheadend would make use of the GPU for the transcoding part.

Have anybody ever attempted a similar setup ?

Thanks,
Gonçalo

Tvheadend only does software transcoding, there has been some experimental hardware transcoding work done focusing on intel & nvidia. Even if Tvheadend did support hardware transcoding on the Pi it wouldn't be powerful enough to transcode 2 concurrent streams.

You also have to think of bandwidth issues, the Pi still uses one measly USB bus shared between the Ethernet and the ports! Last time I tried streaming a complete Freesat mux (45Mbps) over the network it glitched like hell.

tvheadend works just fine with qsv and libfmx, but its a bitch to build, ultra complicated.

the hardware assisted h264 encoder for the pi has to manny flaws, its missing pps/sps and more information, so you cant even bring a transcoded stream from pi through tvheadend.

and btw just so you know, a pi can encode arround 150 fps SD, so thats way more than 2 channels.

danny skjodt wrote:

tvheadend works just fine with qsv and libfmx, but its a bitch to build, ultra complicated.

the hardware assisted h264 encoder for the pi has to manny flaws, its missing pps/sps and more information, so you cant even bring a transcoded stream from pi through tvheadend.

and btw just so you know, a pi can encode arround 150 fps SD, so thats way more than 2 channels.

Last time I tried even one stream it struggled but that was ages ago maybe things have improved!

Oh, ok, I was hoping the tvheadend transcoding was ready out of the box, I'm not looking for an ultra complicated installation here. Does this only apply to the pi, or would it be cumbersome on a i386 as well ?

The ultra complicated build is for intel quick sync, like i said rpi cant encode a proper stream folowing the specs of h264 properly, the tvheadend matroska muxer, and the demuxer for htsp clients cant hanle streams from a pi.

The most easy thing todo is to use a real pc some i7 2600 3770 or well you get the idea a powerfull 4 core machine. And then use software based encoding.

"*Last time I tried even one stream it struggled but that was ages ago maybe things have improved!*

What you have tried is most likely software based encoding then, tvheadend does not support the openmax encoder the rpi has, you need a piped method and to use gstreamer or omxtx for that, and like i said it wont pass the tvheadend matroska muxer og the htsp demuxer.

danny skjodt wrote:

"*Last time I tried even one stream it struggled but that was ages ago maybe things have improved!*

What you have tried is most likely software based encoding then, tvheadend does not support the openmax encoder the rpi has, you need a piped method and to use gstreamer or omxtx for that, and like i said it wont pass the tvheadend matroska muxer og the htsp demuxer.

Nope, this was way back when the Pi was first released (I received mine the day after the release), it was extremely buggy. I already know about omtx and gstreamer but never got around to trying them.

1 day after the release there was no transcoding support at all yet for the pi no omxtx and gstreamer had not even thought about it at that time, so must have been software based what you tried

And software based encoding on a pi1 would be bad, a pi2 can do about 1 channel.

danny skjodt wrote:

1 day after the release there was no transcoding support at all yet for the pi no omxtx and gstreamer had not even thought about it at that time, so must have been software based what you tried

And software based encoding on a pi1 would be bad, a pi2 can do about 1 channel.

Actually I'm confusing decoding with encoding here, I'm remembering trying the video demos not transcoding when the Pi was first released..

I've been up nearly 18 hours now, so you'll have to excuse my confusion.