Composite vs S-Video vs DVB Stream

[XiNull]

I've been trying to create the "Perfect Quality" recording...well as good as my satellite receiver delivers. I have an HDTV and anything that's VCR quality really sucks to watch.

I have seen XSVCD's which can fit onto a 800MB CD that are identical if not better than what I get from my dish. That's what i'm trying to duplicate. Right now I'm trying to determine what type of equipment to use to produce the best quality I can.

Now i know that S-Video is better than Composite. But does the capture with S-Video really make a difference in quality over Composite? And what kind of difference? What kind of advantages does S-Video has over Composite?

And what about DVB direct capture now...is it of greater quality than Composite or S-Video? I would think so since it's a capture of the stream coming in from the dish, but I asked a friend to send me a sample from his DVB card and the results were dissapointing. The video was missing frames and the audio wasn;t sync'ed. Is this to be expected of DVB capture or is my friend simply not capturing correctly?

Any kind of comments or suggestion would be really appreciated. I'm not looking to find the best card or the best capture device...I know that's pretty much up to the software you use. I'm looking for the best Technology (or Type of equipment) to use to capture.

After all Garbage In is Garbage Out!

Thanks,
XiNull

[trevlac]

Now i know that S-Video is better than Composite. But does the capture with S-Video really make a difference in quality over Composite? And what kind of difference? What kind of advantages does S-Video has over Composite?

If you have a sat reciever with s-video out, there should be a big improvement over composite. A composite signal mixes the b&w info with the color info. This has to be seperated to be displayed. The seperation degrades the image. Also, a composite signal is intended for broadcast. So it's bandwidth is by it's intended nature more limited. If you have a higher bandwidth source (like sat tv), conversion to composite will reduce the detail in the picture. (This last comment applies to NTSC. PAL has a higher broadcast bandwidth).

Just view s-video as a bigger pipe. If you have more stuff to go thru, you will get a better result. If you are starting with a trickle, you don't get a benifite from a bigger pipe.

And what about DVB direct capture now...is it of greater quality than Composite or S-Video? I would think so since it's a capture of the stream coming in from the dish, but I asked a friend to send me a sample from his DVB card and the results were dissapointing. The video was missing frames and the audio wasn;t sync'ed. Is this to be expected of DVB capture or is my friend simply not capturing correctly?

I have little doubt that DVB can be converted to analog, and reconverted to digital, with no noticeable difference in quality. It all depends upon your equipment and the compression you are using. On the other hand, coppying the digital stream would be much easier.


Hope this helps

[XiNull]

Thanks for all the info...very helpfull.

Does anyone else have any opinion about DVB capture? Or experience with it and could share information about their captures and if they can produce a higher quality than capturing with S-Video or Composite?

I dont want to spend money on a DVB card and find out that the quality is not what I expected, so i'm aquiring the most information i can get!

Thanks,

[SatStorm]

I move that to the DVB forum

I capture direct the DVB stream years now.
You are in USA (or Canada), so I bet you mean capture the analogue way the DVB transmission, not grabb direct the DVB stream.

Anyway, the DVB stream is the best you can have from that source.
S-Video is far better composite: It has lest colour issues (less colour shifting, better luma). With composite you need excellent cables and you need to adjust the NTSC flows after the capture. With S-Video you need to adjust less (or nothing)

DVB transmissions based on mpeg 2 and as we all know, mpeg depends the quality on the bitrate. If the DVB transmissions has low bitrate, the picture you gonna recieve is bad. Worst SVCD / CVD! From what I read, American providers don't care that much for picture quality but for more channels per TP

[proxyx99]

I From what I read, American providers don't care that much for picture quality but for more channels per TP

You said "quality"? This word is not present in the cable dictionary since the inception of NTSC. More channels? That's more like it. Especially with reruns and back to back advertising.

[trevlac]

From what I read, American providers don't care that much for picture quality but for more channels per TP

But we are used to NTSC TV in the 1st place. So there is much room for improvement.

BTW: You can get at the streams. I was looking at one the other day. Guess what! ~2500 average bitrate 544x480. But damb, I always thought those old svcds looked pretty good. I think the big advantage is that they start with good source. Like making an svcd from dvd.


I thought you were at Mount Olympia ?

[satviewer2000]

Your friend either does not have a sufficiently powerful computer and/or hardware to run DVB properly, or isn't using the right software. I have DVB and I can capture even HD material without a single lost pixel.

DVB gives the BEST possible quality, as you are basically downloading what they are sending, bit for bit. You are getting a 1 to 1 digital data transmission of what is being sent by the satellite. Any other method uses an analog signal, which of course degrades the signal quality.

[PC Master]

To compare, what would be the best -- copying a CD directly (no data loss), or popping it in a CD player, and feeding the audio output to a PC? The copy method will give you a perfect 1:1 copy of the original data.

This should not be confused with quality loss resultant of conversion from your source (CD audio, DVB video) to another format (MP3 audio and XviD video, for example).