I have a composite (phono / BNC) A/V signal from a digital source which I want to record onto a laptop.
I bought a phono to USB wire thinking I could just plug it in and the signal would be there, but the idea did not work.
I tried it on XP and W7, using both Windows MovieMaker and VLCplayer, but was unable to find the picture signal.
The signal is digital, the laptop is digital. I thought it would be a simple procedure, am I missing something ?
I would be grateful for some insight - how can I get this operation to work ?
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USB - universal serial bus. what part of that says video? and besides that composite is not digital.--
"a lot of people are better dead" - prisoner KSC2-303
Wow! I con't believe they make such a cable. What would it be used for?
For your purpose you need something that will convert the analog signal to digital. If USB is your only digital input source (ie. no firewire) you need a capture card/device to USB. Something like the Hauppauge USB-Live-2 Video Capture or similar.
Is your laptop USB2? If not you may have some problems...
--dES"You can observe a lot by watching." - Yogi Bera
As suggested below, Hauppage et al quite happily use USB for video
composite (as opposed to component) is just a copper wire. A copper wire can carry 6v, 240v, or a varying voltage(a signal)
As I understand it, the difference between analogue and digital is the shape of the wave as it varies from 0v to 3v, 6v or whatever.
So my phono/BNC copper wire has a square waveform, a digital signal.
anyone know why it won't show on my laptop screen ?
If I had an analogue signal, I would need a converter, but my signal is digital (see above).
My laptop has USB2, and, being a laptop, it has all the I/O ports a laptop has....
what adapter would I need to convert phono/BNC into firewire ?
Isn't firewire an analogue device ?
Easycaps is the cheapest device just make sure its the genuine product and not the cheap ebay knock off ... that'll get you up an running
Most cables are just "copper wire", but they are designed to take certain signals optimally - a "composite" cable is SPECIFICALLY a continuous analog, 1v peak-to-peak serial baseband Video-only signal with luma & both chroma combined, using an RCA/phono or BNC connector.
Firewire is digital-only, as is USB. They are generic serial data stream pipelines, but when they incorporate video, it is not continuous but packetized, and the digital video signals used are almost ALWAYS component, not composite.
There never has been and never will be a single simple wire conversion between those 2 worlds - it's too complicated for that. Needs an A->D conversion, a composite->component separation, and a levels-matching at minimum before formatting for Fw or USB serial protocols.
So either you are lying about this wire/cable purchase or you were seriously taken in a foolish snake-oil purchase. Or someone is using a very non-standard (bad) method for incorporating analog OUTPUT breakouts via a USB port (in order to save space).
*Even if your SOURCE was digital, by the time it is going out a composite RCA video connection, it is no longer digital but analog, which means you will have to convert it BACK to digital (with accompanying quality loss). If it truly is digital, use a different connection methodology with does incur the D->A->D penalty.
It would help if you actually gave use models of equipment to reference.
one of the items in the OP's link goes so far as to say "Connect your AV equipment to HDD player. Note: PC can't use the cable directly"
However, the descriptions for others are more deceptive. They say "Connect Your USB Equipment To Your Stereo/Video System. Ideal For Computers And Laptops." I'll wager most of the people buying from those listings are deliberately being swindled.
Examples of what is actually needed to get a composite video signal and analog stereo audio into a laptop:
Last edited by usually_quiet; 6th Jul 2016 at 12:48. Reason: typo
Maybe this will clarify it
There are millions of digital signals, that doesn't mean you PC is set up to receive them or understand them
TV is digital during the RF broadcast and after the the tuner and video circuits demodulate aka decode it
But you PC doesn't have a RF tuner built in
Satellite radio is digital, your PC doesn't get that either
USB is a signal interface port
Hard ware that plugs into USB , delivers signals in a format the PC is expecting, determine by the identifier the hardware gives the PC
You plug in a memory stick or external hhd or camera
That device talks to the PC
A simple cable does not do that
You need a video acquisition device, USB video converter to transfer,/input video signals into the PC
You cannot record at 1920x1080 from composite using a Hauppauge HD-PVR. Only 576i or 480i are available. Composite is strictly a standard definition connection.
You would need to use the HD-PVR's component video input and a source with component video out to record at 1920x1080.
[Edit]...and the original HD-PVR only records up to 1080i.
Last edited by usually_quiet; 6th Jul 2016 at 21:08.
Still haven't told us WHAT equipment you are attempting to use as a source...
digital cannot go down a composite media. So why would the designer make 2 analogue outputs from the same unit ?
There is definitely a big quality difference between the two, and only the 'analogue' will make a picture when connected to old TV (phono) conns
I'm getting more confused rather than less. Is that normal with video ?
What does this "Composite is strictly a standard definition connection." mean pls ?
I would tell you but you still haven't truthfully and fully answered me in my model requests...
Not gonna play the "piecemeal troll BS" game.
herder, as far as my statement about composite video being a standard definition goes, please feel free to consult the Wikipedia composite video article.
If there is a "BNC digital connection," it is definitely not composite. It could be one of a couple of other things that resemble a composite connection to the uninformed, but are not. Like Cornucopia, I too have had enough.
Last edited by usually_quiet; 14th Jul 2016 at 14:49. Reason: grammar