Best Captures for RF?

[therock003]

What equipment and procedure should i follow in order to capture tv content from an rf source to as best a quality as possible?

For example at the moment I use a deck DVD recorder,but i kinda hate it.Cause after i capture i have to dub the content into a dvd,and the content must be under 1 hour to fit the best quality (HQ),then i need to copy and extract from the dvd to the comuter,then i need to encode to mpeg-4.It's all a big mess.

So i'm planning on getting a tv-card with rf input (not an antenna) that can capture directly at mpeg-4 with great quality.

So the only thing left is for me to manually remove commercials.

So what do you suggest?

[lordsmurf]

Capturing directly to MPEG-4 with great quality simply is not possible. There must be an intermediary step, as your going from interlace analog to progressive XVID (or whatever MPEG-4 flavor you choose). Direct capture in this format will result in craptastic video with visual flaws aplenty.

[yoda313]

FYI Rf input (when it is not for antenna/cable directly) is not the best. You are infinitely better off using svideo or in a pinch rca composite. It will work with the antenna out from the source you want but it won't be as sharp as you want.

I had tested the rf out from my hddvr and it wasn't very sharp on the coax input on the capture device. The svideo was a lot better. Just a suggestion.

[therock003]

Capturing directly to MPEG-4 with great quality simply is not possible. There must be an intermediary step, as your going from interlace analog to progressive XVID (or whatever MPEG-4 flavor you choose). Direct capture in this format will result in craptastic video with visual flaws aplenty.

Y is capturing directly to mpeg-4 worse than mpeg-2?What does mpeg-2 have to offer that makes it more suitable for capturing purposes?

FYI Rf input (when it is not for antenna/cable directly) is not the best. You are infinitely better off using svideo or in a pinch rca composite. It will work with the antenna out from the source you want but it won't be as sharp as you want.

I had tested the rf out from my hddvr and it wasn't very sharp on the coax input on the capture device. The svideo was a lot better. Just a suggestion.

What do you mean exactly?I have an antenna placed on my roof and there's a cable drawn from there and it ends to a desired destination.May that be a TV,DVD Recorder a capturing device.What i meant was that i was looking for a capturing device that allows rf input ie hooking up the cable rather than rf reception with cards integrated antenna.Cause i've sen some that come with antennas,and such small antennas dont provide good results.

[yoda313]

What i meant was that i was looking for a capturing device that allows rf input ie hooking up the cable rather than rf reception with cards integrated antenna.Cause i've sen some that come with antennas,and such small antennas dont provide good results.

Oh I thought you meant you were trying to capture vhs off of the rf output - that doesn't look very good. However just about any capture device that has an rf jack will allow tuning through either an antenna or cable/satellite. You can set it up in the configuration of the capture program.

What lordsmurf is getting at about mpeg 4 and divx/xvid capturing is that they are lossy formats. They are compressed compared to mpeg2. Mpeg2 is the dvd format that will allow you to author a normal dvd that will be readable by just about any dvd player. Mpeg4 formats like divx and xvid are a different animal and are generally lower in quality than mpeg2 depending of course on what bitrates and resolution you use.

[therock003]

Oh I thought you meant you were trying to capture vhs off of the rf output - that doesn't look very good. However just about any capture device that has an rf jack will allow tuning through either an antenna or cable/satellite. You can set it up in the configuration of the capture program.

Well i understand that a card that has an rf input will capture the signal from the antenna you dont need to be highly intelligent to figure this one out,i meant quality wise which would be the best option,i wouldnt want to go and buy the first card i find with rf input.

What lordsmurf is getting at about mpeg 4 and divx/xvid capturing is that they are lossy formats. They are compressed compared to mpeg2. Mpeg2 is the dvd format that will allow you to author a normal dvd that will be readable by just about any dvd player. Mpeg4 formats like divx and xvid are a different animal and are generally lower in quality than mpeg2 depending of course on what bitrates and resolution you use.

Y,s mpeg2 lossless?No its not.Is it better?No it's certainly not.Just because it
is ancient and needs more disk space it doesnt make it in any way better.

Will capturing from mpeg-2 and converting to mpeg-4 lose quality?You most certainly will,thats why i'm asking for a card that captures directly to mpeg-4,so that there will be no need for conversion to take place,and file will be stored in the newer anfd better mpeg-4 encoding.

Back to my original quations now.Please i am waiting for suggestions.

[edDV]

Well i understand that a card that has an rf input will capture the signal from the antenna you dont need to be highly intelligent to figure this one out,i meant quality wise which would be the best option,i wouldnt want to go and buy the first card i find with rf input.

Y,s mpeg2 lossless?No its not.Is it better?No it's certainly not.Just because it
is ancient and needs more disk space it doesnt make it in any way better.

You still aren't clear if you are capturing RF only off air or if by cable system as well?

These are options for RF input

* Normal NTSC VHF/UHF TV - Over the air analog will disappear Feb '09. NTSC only tuners can no longer be manufactured. Analog NTSC (two digit channels) will remain on cable until at least 2012.

* ATSC Digital tuners - These come in SD 480i only and SD/HD output versions.

* ClearQAM tuner - This will tune non-encrypted digital channels from a cable system. These will include the locals (including HD) and some others.

So you first need to decide what your input needs are. Some tuners do ATSC+ClearQAM+Analog NTSC. Some also encode analog source to MPeg2 (e.g. Hauppauge HVR-1600). Digital broadcasting is already MPeg2 so needs no encoding.

One box, the Hauppauge HD PVR encodes everything to h.264 MPeg4.

Will capturing from mpeg-2 and converting to mpeg-4 lose quality?You most certainly will,thats why i'm asking for a card that captures directly to mpeg-4,so that there will be no need for conversion to take place,and file will be stored in the newer anfd better mpeg-4 encoding.

Back to my original quations now.Please i am waiting for suggestions.

Back to capture what to MPeg4? Not many tuners are doing that today. Most manufacturers are upgrading products for digital broadcasting. The Plextors are analog NTSC only. Expect many new products in the fall.
http://plextor.com/english/products/PX-TV402Uspecifications.htm

There is a new SD option to cap to h.264 off external tuners or cable boxes, the Black Magic Video Recorder.
http://blackmagic-design.com/products/videorecorder/


PS: My bad. therock003 is in Greece. You have other options there. Check out that Plextor Convertx PVR PX-TV402U if it comes in a PAL version. It won't get digital FreeView. A Google search for PAL to MPeg4 tuner didn't find much. The computer you show won't play h.264 MPeg4.

Conversions for Europe
- NTSC VHF/UHF TV would be PAL VHF/UHF TV
- ATSC Digital tuner would be DVB Digital tuner
- ClearQAM tuner would be DVB-T cable tuner.

[therock003]

Well Yes here on Greece we dont have plans to turn everything digital as of yet.Ok well let's break it down.

So far there are only to options when it comes to TV.There's having an Antenna up your roof and hooking up a cable from there to the RF.(Or having a small portable Antenna that connects to the RF of the TV).

And then there's via Satelite, where you need a digital receiver,and you need to pay subscription to get a package where you can browse the package's exclusive channels plus the publicly available channels in (dsr format).

I do have a subscription and satellite dish equipped but the subscribers card is on my dads home and i have access to this channels only when he visits this home (Once a week) so dsr doesnt look like an option since i cant get into a second subscription.Paying once is enough as it is.

So that leaves the RF transmission.The quality that comes from the antenna is not bad,but i described what my issue is with recording from my deck dvd.

Question
Is RF analogue and Satelite Digital?

Well the LNB cable which the satelite signal results to,is analogi snt it?So a DAC conversion must take place from dish to lnb cable right?So incoming signal from satelite isnt exactly digital but analog?Am i right?

EDIT:BTW this blackmagic device what is it?Are thes component inputs?So i need to somehow have an output from my tv and hook this to the inputs and transfer via usb to pc?Is that it?

[edDV]

...
So that leaves the RF transmission.The quality that comes from the antenna is not bad,but i described what my issue is with recording from my deck dvd.

Question
Is RF analogue and Satelite Digital?

Well the LNB cable which the satelite signal results to,is analogi snt it?So a DAC conversion must take place from dish to lnb cable right?So incoming signal from satelite isnt exactly digital but analog?Am i right?

EDIT:BTW this blackmagic device what is it?Are thes component inputs?So i need to somehow have an output from my tv and hook this to the inputs and transfer via usb to pc?Is that it?

RF from your antenna is analog PAL modulated to an analog RF channel. To tune this you need a classic analog tuner card. The job of the tuner card is to demodulate RF to composite PAL, then convert from composite analog PAL to component digital, then optionally convert to MPeg2 or a variation of MPeg4.

Satellite is digital MPeg modulated over analog RF similar to digital broadcasting or digital cable. A digital tuner demodulates RF to MPeg. Most people think of all three as "digital".

You require a card or device that tunes analog PAL and encodes to MPeg4 such as the Plextor Convertx. There are many cards that convert to MPeg2 such as the Hauppauge PVR series.

Compared to MPeg2, MPeg4 is more compressed (smaller files) but also needs a faster computer to play or edit the file. MPeg2 is the more practical solution since most current display cards will decode MPeg2 without loading the CPU.

The BlackMagic Video Recorder is for use with an external hardware tuner like a cable or satellite box. It will accept analog composite, S-Video or YPbPr components and output h.264 MPeg4 over USB2. If your TV or DVD recorder output PAL composite or S-Video, then the BlackMagic device will convert that to MPeg4.

[therock003]

First of i forgot to mention the system on my profile was a computer on my fathers office back in 2001.It has nothing to do with my modern computer which meets the standards for h264 playback and conversions and everything so there's nothing to worry concerning this factor.

Now as to the topic of the discussion we're getting somewhere.What you're posting is the kind of information i was hoping to get out.

But so far infromation about the source is missing.

-Like the Station that does the broadcast,does it have media in digital or Analog format?

-When it broadcasts it needs to convert them to analog so is this step where loss of infromation takes Place?

-Y is RF quality so bad sometimes and results to lots of background noise,week picture and other defects?Is it all due to the transmission protocol,data sent via radio frequency?

Also My DVDRecorder seems to have a component output which makes it ideal to transfer signal to the Blackmagic card and from there do whatever.

-The RF Demodulation is going to take part on the Recorder right?Before it leaves from the component.

-Are there any serious specifications that makedifferent tuner get better results when demodulating rf feed,or is it all about receiving the signal in the best possible condition?I mean is it different from TVT to TV and PVR equipment to demodulate RF Signal

-And the last question i would like to address for now,is this.Is Analog content always interlaced?Cause the videos i seem to capture from RF to my recorder so far seem to be badly interlaced,and i mean badly.

Does it leave the source as interlaced,or is it converted somewhere along the way?

Satelite vs RF though it clearly seems to tilt over to Satelite?

Lots of questions here,and i apologize for that,i really appreciate you taking the time to answer my questions.

[edDV]

...

But so far information about the source is missing.

-Like the Station that does the broadcast,does it have media in digital or Analog format?

-When it broadcasts it needs to convert them to analog so is this step where loss of information takes Place?

Greece like the rest of Europe transmits analog PAL from TV stations. Internally PAL TV stations use a mix of analog and digital source but today most of it is digital. Before transmission, digital is converted to analog PAL for transmission over RF to a particular channel frequency.

Most European nations are converting long term to DVB digital transmission. DVB is a modulation process to transmit digital television over analog RF.
http://en.wikipedia.org/wiki/Digital_Video_Broadcasting

-Y is RF quality so bad sometimes and results to lots of background noise,week picture and other defects?Is it all due to the transmission protocol,data sent via radio frequency?

Analog RF (over the air) transmission quality depends on the power and location of the transmitting antenna, distance to your home, objects in the line of sight path and your home antenna. Home antennas can be omnidirectional (low gain and subject to interference) or directional (higher gain and focused). If you are distant from the TV station transmitter, you need a larger and more directional roof top home antenna such as


UHF antenna

Digital broadcasting follows the same rules but also follows the all or nothing rule. As the signal strength degrades, digital station reception remains clear until sudden breakup and then no picture. This makes pointing the antenna at a digital station more difficult.

Also My DVDRecorder seems to have a component output which makes it ideal to transfer signal to the Blackmagic card and from there do whatever.

-The RF Demodulation is going to take part on the Recorder right?Before it leaves from the component.

The tuner (in this case in the recorder) will "tune" an RF channel, demodulate to PAL and then decode to analog components (YPbPr). The Blackmagic card will convert analog YPbPr to MPeg4 h.264.

Be aware that h.264 requires either a hardware decoder or a strong CPU for smooth playback. It is more demanding than MPeg2. HD resolutions are even more demanding.

-Are there any serious specifications that makedifferent tuner get better results when demodulating rf feed,or is it all about receiving the signal in the best possible condition?I mean is it different from TVT to TV and PVR equipment to demodulate RF Signal

Yes PAL tuners vary in performance. A DVD recorder tuner will have a middle to upper middle performance. More important is the antenna and pointing the antenna to the TV stations correctly.

-And the last question i would like to address for now,is this.Is Analog content always interlaced?Cause the videos i seem to capture from RF to my recorder so far seem to be badly interlaced,and i mean badly.

Does it leave the source as interlaced,or is it converted somewhere along the way?

Yes analog PAL is always interlace. So are most SD DVB (576i) an HD DVB (1080i). Some TV stations broadcast 720p progressive mostly for sports. Interlace is used because it makes more efficient use of transmission bandwith. Interlace is no problem for most TV sets. Computer viewing requires a deinterlacing player such as VLC or PowerDVD.

Satelite vs RF though it clearly seems to tilt over to Satelite?

That may or may not be the case. If you have good PAL reception at your location, the quality will be superior to highly compressed 576i MPeg2 or MPeg4 off the satellite. If you have poor PAL reception, the satellite will look better.

Greece specific websites:
http://en.wikipedia.org/wiki/Television_in_Greece
http://www.dvb.org/about_dvb/dvb_worldwide/greece/