USB cam directly on RPI

Discussion about this major DATV Project. See https://wiki.batc.org.uk/The_Portsdown_Transmitter
VK5YYY
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Re: USB cam directly on RPI

Post by VK5YYY » Sat Aug 25, 2018 3:16 am

Hi Dave

I don't have DATV Express board but I do have Pluto and Lime
Having tried Pluto and Lime with Charles's latest DATV Express software I was quite impressed
Evariste has sent pictures with lime and RPi can't find any reference to Pluto and RPi DATV Tx
Will Portsdown someday support lime and pluto too, or has that already been done?
920 webcam, pluto/lime and Portsdown running the show would be a great combination
Compact, easy to construct, runs off one power rail and all together reasonable price for the outcome
Easy for me to say I'm a copier not a talented developer like yourself and the other great minds mentioned
My interest in Portsdown has waned after my business treated me to a DVB-S2X modulator
The 920 webcam is a game changer, lovely H264 picture with sound, it's got my interest back

Cheers Roger VK5YYY
Last edited by VK5YYY on Sat Aug 25, 2018 1:00 pm, edited 1 time in total.

G8GKQ
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Re: USB cam directly on RPI

Post by G8GKQ » Sat Aug 25, 2018 9:59 am

Hi Roger

There is experimental Portsdown code for the Lime Mini (DVB-S only). It needs to be loaded from the update screen. Lime USB support and DVB-S2 are eventually planned, but there are only so many hours in the day...

VK5YYY
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Re: USB cam directly on RPI

Post by VK5YYY » Sat Aug 25, 2018 12:59 pm

Sent pictures tonight to VK5RDC our local 23cm repeater which is 55km achieved with 250mW out of Portsdownunder into 18db Grid Dish
The 920 webcam's 1080P using H264 is very impressive once I figured out the settings
The stunning picture was very stable although the auto focus on the 920 webcam is nothing special, particularly close up, gets there eventually

Portsdownunder is sporting a new PA based on the new mini circuits PHA-23HLN+ which is good for a bit over 1/2 a watt
Better still mini circuits provided 4 samples free of charge and free shipping, next step to hybrid couple two for a watt
https://www.minicircuits.com/pdfs/PHA-23HLN+.pdf

The new PA makes Portsdownunder fully 5 volts and takes between 1.5 an 2 amps
Two 5000mAhr power banks, one for the RPi and one for the PA, although is will work on one, with the odd lightning flash
May I pass on the complements of the viewers I had tonight, one of them said the pictures look better than my professional DVB-S2 modulator
Thanks again Dave, your efforts are extremely appreciated, you've outdone yourself!

Cheers Roger VK5YYY

VK5YYY
Posts: 81
Joined: Sun Sep 27, 2015 1:47 am

Re: USB cam directly on RPI

Post by VK5YYY » Tue Oct 02, 2018 12:35 pm

Hi Dave

I read on the Wiki and heard you repeat it at CAT18 that the C920 web cam needs 2Msym and 7/8 Fec for 1080P video
Could it be that you actually mean greater than or equal to 2Msysm and 7/8 Fec to support the bit rate of the C920
The C920 works great at 5Msym and 3/4 Fec that we use in VK and it's smooth as silk
I just don't want you to undersell your marvelous little creation and people think there is a limitation to only those specific parameters
Has anyone tried any of the other Logitech range IE C930 or others with better/different features to see if they work
Roll on H264 with sound!

Cheers Roger VK5YYY

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keng8vdp
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Re: USB cam directly on RPI

Post by keng8vdp » Wed Feb 13, 2019 2:09 pm

Hello all,

Ive just completed first stage of my Portsdown and happy to say its working using the inbuilt testcard and contest card as the source.
Recieving perfect on a Tevion satelitte receiver.
If I plug in my Easycap and my 1v p/p testcard generator into that. Then select Video View In MENU 2 I can see my composite input
on the PI screen. Same if I plug in my logitech v-uj15 Webcam.

However , with either of these 2 devices connected (not at same time !) and selected as "Source" Menue 1 / CompVid
I see NO video on my receiver when I transmit or on the PI screen. I see just a blank screen on RX ( the signal is there )

Ive tried booting the PI with it ( Easycap or Logitech ) already plugged in and also tried booting PI then plugging one in.
The result is the same. I see it in Video View Menue 2 , but not on the transmitted stream / PI screen or on my receiver.
The receiver appears to remain locked and appears the content is just a black screen , if you know what I mean.

Am I missing something. Maybe Im not understanding right.

Any help appreciated. Ken G8VDP

G8GKQ
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Re: USB cam directly on RPI

Post by G8GKQ » Wed Feb 13, 2019 5:59 pm

Hi Ken

Did you purchase your EasyCap from the BATC or elsewhere? The transmit software is very fussy about the exact chipset in the EasyCap, whilst the VideoView facility is more forgiving. There are 4 internal chipsets that I know of and they all look the same on the outside.

If you can get to the Linux prompt and type lsusb it will tell you what sort of device it is.

Dave

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keng8vdp
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Re: USB cam directly on RPI

Post by keng8vdp » Wed Feb 13, 2019 6:29 pm

Hi Dave, I've had the easycap for ages and that worked OK a bit back (2 years at least) using Portsdown in dirty mode.
Here's a video of it.
https://youtu.be/GocQzQdZZWA

The webcam I was just "hoping" and because I could see it in video view I again "hoped" it might work.

If it doesn't work then no harm.

Thanks Ken

Since I posted the above, my friend Gary M1EGI kindly brought his Capture device and we tried that and all was well. ( that's what friends are for )
Also tried his Logitech V-U0015 webcam and that worked too. ( that's what friends are for 2 )
Needless to say , I had ordered one from BATC within the hour and purchased a used Logitech V-U0015 for under a tenner.

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