Streaming IPTS with Pluto

Discussion about this major DATV Project. See https://wiki.batc.org.uk/The_Portsdown_Transmitter
G3GJA
Posts: 166
Joined: Sun Nov 20, 2011 3:44 pm

Re: Streaming IPTS with Pluto

Post by G3GJA » Fri Sep 17, 2021 8:59 am

Mike, good to hear you've made progress.

Like you, I tried the scripts and installing FFMPEG separately and got nowhere, but with the FreeStreamCoder that has FFMPEG built in it was a breeze.

I should have mentioned that I am using a fairly new PC, a Dell Optiplex 3080. It has an Intel Core i5 10500 @ 3.1GHz and UHD 630 graphics, 16GB RAM @2666MHz and a Crucial 466GB NVMe SSD.

I suspect that a laptop may not cope because of the compromises made to extend battery life and size. Typically, processors are used having a U suffix indicating ultra low voltage. They have a much lower operating voltage and TDP (Thermal Design Power). In a laptop TDP is kept low because it's difficult to get the heat away and that means the CPU core speed will get throttled back under heavy load, exactly what coding does to a CPU.

One of my work laptops has a sixth generation Core i7 / 8GB RAM and a SSD that I will need to run OBS and FreeStreamCoder for an upcoming club demo. It will be interesting to see how it performs and compare its spec. with your laptop.

Clive G3GJA

g0mjw
Posts: 1709
Joined: Sat Sep 20, 2014 9:15 am

Re: Streaming IPTS with Pluto

Post by g0mjw » Fri Sep 17, 2021 9:02 am

Finally in this marathon thread you should test that it works before attempting to transmit on air. One way to do this is to use VLC.

So, let's say you want to test H265 nvidia hardware encoding from OBS-camera.

c:\ffmpeg\bin\ffmpeg -f dshow -i video="OBS-Camera" -thread_queue_size 512 -f dshow -i audio="OBS-Audio" -vcodec hevc_nvenc -s 1920x1080 -bf 0 -pix_fmt yuv420p -b:v 340k -r 15 -preset slow -profile:v main -rc cbr_hq -rc-lookahead 5 -acodec aac -aac_coder twoloop -ar 48000 -ac 1 -b:a 32k -f mpegts -muxrate 435k -streamid 0:256 -streamid 1:257 -max_delay 2500000 -pcr_period 40 -pat_period 0.4 -metadata service_provider="G0MJW" -metadata service_name="Mike" -y "udp://127.0.0.1:8282?pkt_size=1316"

That command does the encoding and sends it to the local host - i.e. the computer you are running it on. With that running, open VLC.
Then Media->Open Network Stream and enter the URL udp://@:8282 and play it. If all is well you should see your mpeg TS decoding nicely in VLC. If it doesn't work locally, it is not going to work remotely.

To use H264 with software encoding - note this won't work very well with fast movement as it is highly compressed.

c:\ffmpeg\bin\ffmpeg -f dshow -i video="OBS-Camera" -thread_queue_size 512 -f dshow -i audio="OBS-Audio" -vcodec libx264 -s 768x432 -r 15 -bf 0 -pix_fmt yuv420p -b:v 300k -preset slow -profile:v main -rc cbr_hq -rc-lookahead 5 -acodec aac -aac_coder twoloop -ar 48000 -ac 1 -b:a 32k -f mpegts -muxrate 440k -streamid 0:256 -streamid 1:257 -max_delay 1500000 -metadata service_provider="G0MJW" -metadata service_name="Mike" -y "udp://127.0.0.1:8282?pkt_size=1316"

for hardware encoding

c:\ffmpeg\bin\ffmpeg -f dshow -i video="OBS-Camera" -thread_queue_size 512 -f dshow -i audio="OBS-Audio" -vcodec h264_nvenc -s 768x432 -r 15 -bf 0 -pix_fmt yuv420p -b:v 300k -preset slow -profile:v main -rc cbr_hq -rc-lookahead 5 -acodec aac -aac_coder twoloop -ar 48000 -ac 1 -b:a 32k -f mpegts -muxrate 440k -streamid 0:256 -streamid 1:257 -max_delay 1500000 -metadata service_provider="G0MJW" -metadata service_name="Mike" -y "udp://127.0.0.1:8282?pkt_size=1316"

Hopefully these examples help.

mccla5214
Posts: 61
Joined: Sun Sep 05, 2021 1:45 am

Re: Streaming IPTS with Pluto

Post by mccla5214 » Fri Sep 17, 2021 10:08 am

Hi Mike,

Thanks for that post, I was wondering just how to get the Pluto to work directly with OBS. I'm putting in the GPS lock on the Pluto to keep it stabilized on 1296 and found a little Windows 10 block that looks like it would be fun to try with.

I'm just now finding out little issues like the Nvidia and Intel graphics card in my laptop don't play well so I see a new computer in my future with a decent GPU card. Any suggestions on what I might look for. I've been out of the desktop computer for quite a while since the company I worked for did everything with laptops (no need for anything bigger). I think the last CPU I had was an I5. I think I read in the last couple of days that they are up to I9 or something in that range. Looking forward to it.

Thanks again for the post, that should get me started down the road.

Mike/KA5TDA

g0mjw
Posts: 1709
Joined: Sat Sep 20, 2014 9:15 am

Re: Streaming IPTS with Pluto

Post by g0mjw » Fri Sep 17, 2021 10:49 am

Hi Mike

I have an ASUS laptop with built in Nvidia and 4k display. The more recent intel CPUs have H265 encoding built in so having Nvidia is less important, but really handy for applications that make use of CUDA cores.

You should not have problems with the two graphics cards, most likely it is an issue with the drivers than the hardware. Save many $ by re-installing the drivers. Modern laptops have far too few ports.

If you are building a desktop from new note graphics cards are hard to come by at the moment but you already have the 1660. My recent desktop used AMD as it was best value. Mine is a Ryzen 5 3600 but the 5600 is out now. You need a graphics card with these CPUs. I build from scratch. It isn't that difficult. Following Paul's Hardware is a good idea.

https://www.youtube.com/c/paulshardware

The PC I built last year has:

Ryzen 5 3600
Gigabyte Aorus X570 AORUS ELITE (Socket AM4/X570/DDR4/S-ATA 600/ATX)
Gigabyte GeForce GTX 1660 SUPER OC 6G - £225 when I bought it, £430 now.
Corsair CMK16GX4M2B3200C16 Vengeance LPX 16 GB (2 x 8 GB) DDR4 3200 MHz C16 XMP 2.0 High Performance Desktop Memory Kit
Samsung 970 EVO Plus 500 GB PCIe NVMe M.2 (2280) Internal Solid State Drive (SSD) (MZ-V7S500)
Corsair CP-9020178-UK RM650x 80 PLUS Gold 650 W Fully Modular ATX Power Supply - Black
Corsair CC-9011077-WW Carbide Series 100R Silent Mid-Tower ATX Computer Case - Black

Bear in mind that was a year ago. I went for a mid-range motherboard with a large number of USB ports. The latest Intel CPUs have caught up on AMD but it won't make a huge difference. We don't need the latest fastest hardware for this, better to invest in RF power amplifiers than high spec PCs. The best time to buy hardware is Oct/nov before the prices go up for Christmas. Avoid buying graphics cards!

Mike

mccla5214
Posts: 61
Joined: Sun Sep 05, 2021 1:45 am

Re: Streaming IPTS with Pluto

Post by mccla5214 » Wed Sep 29, 2021 8:38 pm

Update on Portsdown 4 sending with Pluto,

Have tried 333, 500, 1000. 500 won't work at all, the MiniTouner Express never locks. The 333 and 1000 both stop after several hours of transmitting. Don't know how to narrow it down to a problem in the Pluto or the PD4. All I have to do is stop transmit wait about 5 seconds (if I do it faster it won't start transmitting) then turn transmit back on and it will go back to working. I've tried both Test Card and PI Cam as sources to eliminate it being something in FSC. Both do the same thing. I'll try and put a clock in front of the PI Cam to time how long it takes.

If anyone has any suggestions as to what I can look at in the PD4 OS, let me know and I'll try and narrow the issue down further.

The streaming with FreeStreamCoder is working well. It has issues with my NVidia graphics card but that will be corrected when I get the new computer in that was suggested. Just waiting on chip prices to drop.

Thanks all for the assistance,

Mike/KA5TDA

mccla5214
Posts: 61
Joined: Sun Sep 05, 2021 1:45 am

Re: Streaming IPTS with Pluto

Post by mccla5214 » Sat Oct 02, 2021 9:50 pm

Have run several tests to determine how long it takes for PD4 with PLUTO on USB to stop transmitting and it ranges from 9 hours 19 minutes to 6 hours 50 minutes. Three of the runs were 6.83 hrs. (two of them were identical at 6.83) and 6.75 hrs.

My next step is to move Pluto off the USB and put in on ethernet to see if it is something to do with the USB connection.

Mike/KA5TDA

g0mjw
Posts: 1709
Joined: Sat Sep 20, 2014 9:15 am

Re: Streaming IPTS with Pluto

Post by g0mjw » Sun Oct 03, 2021 8:02 am

I don't think it was ever intended for continuous transmissions. Possibly a memory leak. This doesn't sound like a standard application to me. Consider it a timeout timer for free. Best to reset once an hour maybe.

Mike

mccla5214
Posts: 61
Joined: Sun Sep 05, 2021 1:45 am

Re: Streaming IPTS with Pluto

Post by mccla5214 » Sun Oct 03, 2021 2:17 pm

Hi Mike
Thanks for the update. What is the recommended way of transmitting DVB-S on a 24/7 basis? I wanted to have a -S signal on 23cm to allow other Hams a cheap method of picking up a DATV signal using a standard STB here in the US.
Mike

g0mjw
Posts: 1709
Joined: Sat Sep 20, 2014 9:15 am

Re: Streaming IPTS with Pluto

Post by g0mjw » Sun Oct 03, 2021 3:44 pm

There is no recommended way I am aware of but you could always do it in Gnuradio which would be easy with a pre-recorded TS looping, in fact you could even go so far as to record the I/Q and simply send it over and over again from a digithin. What's wrong with having a short break every few hours?

Mike

G8GKQ
Site Admin
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Re: Streaming IPTS with Pluto

Post by G8GKQ » Tue Oct 05, 2021 3:24 pm

Mike

The recommended way of transmitting DVB-S on a 24/7 basis with the Portsdown is to use a LimeSDR Mini as the transmit device and select either "Boot to Continuous TX" or "Boot to Keyed TX" in the console menu. This will reboot the Portsdown every 12 hours to clear any hang-ups (or memory leaks, although I am not aware of any).

There are at least 3 repeaters that have used this set-up in the UK for well over a year with no problems.

The Pluto (when used with the Portsdown) is simply not reliable enough for 24/7 DATV operation. I don't know why, but I am not going to investigate it as we have a proven alternative solution.

Dave

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