OBS Studio + PLUDO SDR TX DATV howto?

  • Hello, working to get everything ready to transmit DVB-S2 DATV via QO-100 from GG66LW.


    I noticed that Pluto with F5OEO firmware and OBS Studio is almost standard among the stations I watch on DATV, I tried to search several places on how to configure OBS Studio but either it was too basic or not clear. I just installed OBS Studio sftware here, I never used this software before for anything so I don't even know where to start configuring it. Along OBS studio I also installed VNC and FFMPEG ( well, ffmpeg is a difficulty apart, there is no installation, just throwing the files inside C:/FFMPEG ?? ) What about " Portsdown " is it needed? Is it a hardware or a software?


    So if you please have any information to share or indicate I would appreciate.


    PS: I am aware about this wiki: https://wiki.batc.org.uk/Custom_DATV_Firmware_for_the_Pluto but it is not clear/too advanced to me.


    Thank you.


    Ed PY2RN

  • Hi Ed,

    Portsdown is a hardware system for DATV: https://wiki.batc.org.uk/Portsdown_2020. I am using the 2019 version, but with vMix. I have tried OBS and Pluto, but without success so far. rtmp and udp don't work here. I am also interested to see the right settings and the proper script for H265. If you are using Pluto, I think you don't need any Portsdown hard- or software, just the right OBS settings. Maybe someone could point us to the right information.

    regards

    Gerhard OE3GBB

  • Hello Ed,


    you need no Portsdown. Its an additional Hardware.


    there are two different ways with the OBS Studio. RTMP streaming or UDP over the record mode. Both work with the Pluto.


    But before let me know what PC are you using? Is there a Nvidia GPU installed? May be a GTX 1050 ? The best way to encode the Video stream in H265.


    Robert

  • Hi Robert,

    I have seen your transmissions over the satellite. I am using a GTX1050 card in a i7-9xxx PC and it is working very well using vMix, Portsdown and Toms script. But I want to use OBS and pluto in the future, as my vMix trial license is just for another 4 weeks.

  • Hello Gerhard,

    yes, I tried diffent equipments, but finaly had the best results with the PLUTO and a GTX-1050 for H265 encoding.

    Your i7-9 is absolutely sufficient. The hardest job is encoding the H265 signal, and with the GTX-1050 you have a minimum load on the intel CPU. Can do additional other things at the same time, MiniTioune RX deocoding for example no problem.


    The trick for H265 encoding is to use the record mode from OBS as UDP multicast, not streaming point to point. You can in the record mode select the udp stream for the Pluto.



    The rest will be done from Evaristes (F5OEO) firmware in the Pluto and the ADALM-PLUTO DVB Controller, pre installed in Evaristes software package.



    These are in short form the mainly steps ...


    73´s de Robert

  • What you need are some profiles and examples to get you started. You also need an H265 encoder, e.g. Nvidia card of little box from China. Email me and I will try to help. OBS is the program to use, with UDP to the Pluto running Evaristes firmware. This can be USB or over Ethernet but if USB it needs to be on the same computer. The BATC Wiki should be easy to follow...maybe we need to work on it.


    Mike

  • One issue I and another local person has found with the Pluto when using the USB to Ethernet adaptor is a lock-up of the Pluto which can be caused by any sort of current surge on the system, so look for the ground mod to apply to the Pluto to help remedy this.


    If you run it from the Ethernet adaptor then it needs a separate 5 Volt power source. If you find the Pluto stops responding to the web browser trying to control it, then just try unplugging the USB adaptor from the Pluto give it a second or two and then plug back in, if that clears it then look to do the modification, or figure another way to equalise the power ground with signal ground in the device.


    That issue caused me hours of head scratching.


    I use OBS, with the H265 HDMI encoder to the Pluto via Ethernet adaptor.


    Adrian

  • Hi Ed,

    Portsdown is a hardware system for DATV: https://wiki.batc.org.uk/Portsdown_2020. I am using the 2019 version, but with vMix. I have tried OBS and Pluto, but without success so far. rtmp and udp don't work here. I am also interested to see the right settings and the proper script for H265. If you are using Pluto, I think you don't need any Portsdown hard- or software, just the right OBS settings. Maybe someone could point us to the right information.

    regards

    Gerhard OE3GBB

    Hi Robert,

    I have an i7/16GB Windows10 . My display cards are AMD Radeon HD 6450 (I have two in the PC)


    Thank you


    Ed PY2RN

  • I believe that the Radeon HD 6450 will help with hardware acceleration for MPEG2, H.264 and VC-1 high definition video formats, so if you are happy with H264 streaming to the Pluto it will be fine.

    My cards do not support H265 hence going down the HDMI box route. The box simulates another display screen and whatever picture and audio is sent to the HDMI port, it encode into H265, (or H264 if you set it for that). So older PC/graphics cards can be used.


    The software interacts between the Pluto firmware from F5OEO and the HDMI encoder and sets the parameters automatically.

    It does not necessarily give the highest definition possible but, I found it to be reliable in both video and audio. There is a drawback in that it does not seem to pass the correct aspect ratio through to Minitioune software, at least in the version I am running.


    Hope it helps


    Adrian

  • Which firmware is necessary on the Pluto? Will the UDP streaming work with the latest release or is the beta ("for the brave") needed?


    If no HW acceleration is available for H.265, is there a software encoder available for OBS?


    DD4YR

    Thanks Robert for that desription, couldn't find this trick somewhere else.


    73, Thorsten

  • Hello Thorsten,

    the beta "for the brave" is the better choice, because ther is a video stream analyser included with which you can easy adjust your video bitrate from obs for the correspending SR. Every SR needs a different video bitrate for best results. Rule of thumb is to set the video bitrate at about 75% of the SR. And reduce the audio bitrate to the minimum, 32kbps with OBS. And framrate 25.


    If you have no H265 encoding GPU you can use an external hardware encoder. Works also with the same Firmware from Evariste. See above what Mike (G0MJW) wrote..


    Software encoding (with DATV-Express transmit software) is very cpu intensive. It did not work well on my pc.

    With DATV-Express you dont need the firmware from F5OEO for the Pluto. But it seems, DATV-Express is no more supported :-(


    73´s de Robert

  • Morning Robert,


    thanks for the information.

    Ok, will try the beta (althought rtmp streaming seems to be broken).


    Unfortunately this HDMI-H.265 encoder seems to be rare and out if stock at ebay.

    Any ideas for further sources or alternative devices?


    With direct RTMP streaming from OBS to Pluto i can scale down audio e.g. to 8KBit/s (through the URL parameter).

    Can this be achieved with the UDP variant too?


    73, Thorsten

  • You can send the audio and video to ffmpeg running on your PC and then forward the TS as UDP to the Pluto. That TS can contain anything you want. You can also modify the Pluto scripts but they are held in a ramdisk so will not survive a reboot. For a while I was uploading modified scripts each time.


    The Radion HD 6450 is a very old card and does not have H265 encoding as far as I am aware. The Nvidia cards like the GTX1050/1060 are a better bet, or the Jetson Nano. Make sure it has H265 hardware encoding supported in OBS.

  • Just made some tests and recogniozed, that Pluto is produzing quite strong shoulders. I measured about -18 dB at very little output drive off the Pluto. After the amplifier and over the satellite I could see them when I adjusted my signal to the strength of the beacon. Then I tried same with Portsdown / LimeSDRmini. Shoulder out the mini were -30dB and no shoulders on the satellite.
    Shoulders at the Pluto signal are not related to the output drive.
    Has anyone recognized similar behaviour?

  • Gerhard,

    you wrote in the BATC WB chat, you´re using a SSB power amplifier.

    Is the drain current adjusted for DATV use? Maybe you are using the non linear part of the power amplifier.

    How much power do you use of this pa ?

  • How can we reduce the audio bitrate in OBS below 32kS? Would be interesting for RB-modes.

    Not in OBS directly, but via RTMP parameter at the Pluto (see attachment). Take a look at the Pluto's internal webpage, section "PC with Vmix or OBS".

    Actually the audio bitrate can be reduced far below 64kbit/s. I tried this down to 8 kbit/s, because i was short on bandwidth.

    Sound like though the phone, but sufficient... :D