F5OEO / rpidatv

Digital Television Transmitter on Raspberry Pi
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TS bitrate is different of the value put in the command. #35

Closed csarmo closed 8 years ago

csarmo commented 8 years ago

I was running the rpidatv program several times with several .ts files. The program run without error, i use the SDR# aplication to watch the RF signal generates by the raspberry pi. The problem i have is when i try to demodulate the RF with leandvb. I got the PSK symbol clouds for half a second then the PSK gone. I was looking some of the issues concerning to the leandvb in its official page and i found two of the issues that could be the cause:

I think my problem is the second one, so i use some .ts with known bitrate, but i noticed that the rpidatv, during execution in the terminal fprint:

TS bitrate should be "bitrate"

is lower that the one i setup in the rpidatv command (in the "-s" parameter). I'm using the B+ raspberry. Please help with this, if i wrong about those values, or if there's a real issue with my rpi model.

F5OEO commented 8 years ago

You can take, any transport stream file : modulation/demodulation should work , decoding video could be too slow or too fast, but that's an other problem.

-s is samplerate, not bitrate ! Bitrate is SampleRate_2_188/204*FEC That explain your interrogation.

Have you get the latest leandvb ? What is your command line for leandvb and rpidatv?

csarmo commented 8 years ago

I use the wget http://www.pabr.org/radio/leandvb/leandvb.cc command, i think this is the latest leandvb. I use for the transmitter: sudo ./rpidatv -i media.ts -s 250 -c 1/2 -m RF -f 437.5 -l In the receiver part i use the command mentioned in the leandvb official page: rtl_sdr -f 437500000 -s 2400000 - | ./leandvb --gui | vlc -

F5OEO commented 8 years ago

Last leandvb is now on https://github.com/pabr/leansdr You have to set the symbolrate to leandvb You can inspect the example script : https://github.com/F5OEO/rpidatv/blob/master/scripts/leandvb2video.sh

csarmo commented 8 years ago

Ok i was on my way to try that but i have had some issues concerning the rtl_sdr library. Any way thanks.