DVB capture questions [Archive]

symonjfox

14th May 2003, 13:36

You need a DVB card. You must chose your own between DVB-C (cable), DVB-S (satellite), DVB-T (terrestral).

I use a DVB-S board (Twin Han 1030) but I advise you to spend something more and buy a Sky Star 2 board (less problems and better compatibility).

All those boards save streams directly in MPEG 2 TS or PVA. Some can record directly to MPEG 2 PS (program stream, the one used with your computer). Obiously you can losslessly convert them to MPEG 2 PS. You don't need to reencode those streams to hffyuv because the record is EXACTLY what your station wants to broadcast to you, so it's just a waste of time.

You can't skip commercials. If you want it, you must stop the recording and restart when they are over.
I prefer to record everything and cut them off using TRIM (11223,34555) command in avisynth.

numlock

14th May 2003, 15:36

One more question. Since it is MPEG-2 will I have to reencode the whole file after I cut out the commercials are is it possible to do it without reencoding ? From my experience whenever I had to edit MPEG-2 files I had to reeencode it.

TIA

ultimatebilly

14th May 2003, 15:50

There are a few programs that can cut and edit mpeg2-streams without reencoding...
I think one of them is mpeg-vcr, another one m2-edit, and there are probably more I can't remember at the moment or don't know about...
You can cut the video with TMPEG, but not the ac3...
I think you can cut the ac3 with nandub, but I never tried, and don't know if it works...
And I think it may be problematic if you cut the video and audio in 2 different applications, because for example TMPEG creates often some overlapping (because it doesn't force you to cut on keyframes...).
There was a freeware java-tool, called ds.jar, which was able to cut mpeg2 and ac3 simultanously if I remember correctly, but unfortunately it is not available anymore, because the author chose to remove it from the net, assumably due to legal issues...
But I never worked with DVB myself, so I may be wrong about its ability to cut...
But I read something interesting just at the moment:
Apparently Vidomi is able to cut mpeg2 streams containing ac3, if you set it to "MPEG copy code"...
Here is the manual:

http://www.pctvsat.com/html/mpeg_2_ac3_schneiden.html

It is in german, but I think the pictures should be sufficient...
It uses ds.jar to demux audio and video, but you may be able to get the ac3 with nandub (can it parse mpeg2-streams???) or virtualdubmod, and demux the video with tmpeg...
But, as I said before, I'm only guessing here, I have no real clue about this whole think...
Hope this helped anyway...

symonjfox

14th May 2003, 18:57

My way (the simplest way :) ) is:

1- Record to MPEG 2 PS using ProgDVB (freeware) or WinDTV (included with my board).
2- Demux (separate audio and video) using Pvastrumento (wich will cut off bad frames and perfectly resynch audio and video).
3- Avisynth

I create something like this

Loadplugin("C:\Programmi\AviSynth 2.5\plugins\MPEG2Dec3.dll")
Loadplugin("C:\Programmi\AviSynth 2.5\plugins\MPasource.dll")
V=mpeg2source("d:\temp\baucete.d2v",ipp=false,CPU=4)
V=Bilinearresize(V,352,576)
V=Letterbox(V,8,8,8,8)
V=Converttoyuy2(V)
A=mpasource("d:\temp\audio031.mp2", normalize=true)
Audiodub(V,A)
Trim(8140,37975) ++ Trim(46991,85910) ++ Trim(96552,141279) ++ Trim (151196,166736)
As you can see I use this script just for creating CVDs. Else I would keep a bigger resolution and YV12 color space.

Not all channels can be converted to DVD video without a recompression, since there are many channels that have particular resolution, not supported by DVD standard (maybe your player will play it ... maybe not, who knows?).

I found these resoltions over Hotbird satellite.
720*576 (standard D1)
704*576 (non standard)
544*576 (non standard)
480*576 (non standard, maybe playable since it's SVCD res)
352*576 (standard 1/2 D1).

I have no DVD-R so I can't tell you. I'm stuck to SVCDs and CVDs and (off course) Xvid :)

For not recompress everything, you should demultiplex using Pvastrumento and then remultiplex using BBmpeg using DVD settings.

Zhnujm

14th May 2003, 20:53

if you want to create a dvd out of the capture i would recommend you tmpeg dvd author as you can cut out the commercials with it during auhtoring without reencoding (at i-frames).
also all non standard dvb resolutions could be played with most dvd players (i have not seen one that cant).

22nd May 2003, 18:49

I cut out the commercials using PVACut 3.50 / PVAView. Works like charm (I-frames only), no re-encoding.

bb

ronnylov

23rd May 2003, 16:35

Originally posted by symonjfox
I found these resoltions over Hotbird satellite.
720*576 (standard D1)
704*576 (non standard)
544*576 (non standard)
480*576 (non standard, maybe playable since it's SVCD res)
352*576 (standard 1/2 D1).

704x576 is a valid PAL DVD resolution so it should say "(standard cropped D1)" in your table. I have a DVD-R burner and the authoring programs accept 704x576 as valid resolution and it plays without problems on all players I have tested.

Avisynth is only useful when reencoding. I have used m2-edit pro and womble mpeg2vcr to edit. I'll test PVACut because it is probably easier than demuxing pva with PVAS, remuxing to mpg with bbmpeg, edit with m2-edit, demux again with tmpgenc and author with dvdmaestro as which has been the dreadful time consuming method I have used so far...

kastro68

28th May 2003, 21:27

Originally posted by symonjfox
You need a DVB card. You must chose your own between DVB-C (cable), DVB-S (satellite), DVB-T (terrestral).

I use a DVB-S board (Twin Han 1030) but I advise you to spend something more and buy a Sky Star 2 board (less problems and better compatibility).

Hi,
I'm a complete noob at DVB capturing...actually, i would be worst than a noob, because I haven't even tried it yet...and I'm not familiar with the jargon yet. I am familiar with analog capture via virtualdub though.

I was planning on trying out DVB-S capturing and have some questions before I actually go out and buy a DVB-S card.
-does it matter what country I live in? I can receive satellite signals...and the dish is already up.
-Are there different types of satellite signals? I read in some post that there is...eg different transfer rate. Would I need a DVD-S board, regardless of the signal type?
-would there be a significant difference in quality compared to say feeding the satellite video via s-video or banana plug into the video card, and capturing using virtualdub?
-would the sound be fed in through sound card? or does the DVB-S board also handle sound? My thoughts from what i read in other posts is that the sound and video gets captured muxed. I guess this question isn't really that important.

I had some more questions but it I forgot what they were... I'll post them if I remember.

Thanks.

symonjfox

29th May 2003, 14:02

1- It should not be a problem in which country you live AFAIK. If there's a Sat recever that can play fine, a DVB card should go too.
I live in Italy but I heard a lot of Canadian people that have my DVB-S board. Maybe if you want to watch PAY PER VIEW channels ... there are different systems from Europe and other continents, but here I can't help you.

2- AFAIK there are mainly 3 kind of trasmissions: DAB (audio only), DVB (audio+video) and DATA. All kind should work fine on any DVB board, but any board has its own good and bad.
Channels can be very different, depends on resolution and datarate, but there's NO problem, a good DVB card does handle them correctly.

3- Yes, it is!! mainly 4 reasons:
1: YV12 colour space (more speed on editing)
2: if you have a DVD-R burner you can do a DVB 2 DVDR conversion with NO recompression (high quality)
3: Less disk space required: try to capture a 25 fps 720x576 YUY2 film using HFFYUV compression and try to capture the same directly in MPEG2 ...
4: when you're recording something you can do something else with your computer (yes, it's better having 2 hard disk, one for system and programs and the other JUST for capturing).

4- Audio is a normal MP2 file. It is generally decompressed by software, but it takes low CPU timing. Off course when capturing, will stay the ORIGINAL MP2 that generally is 192 or 256 kbs, so good quality. There might be some trasmissions in AC3 but I have never seen that.

I hope to be useful for someone :D

benf2

29th May 2003, 15:21

@symonjfox
are these cards you refer to for C-Band or will they work with DirectTv?

trbarry

29th May 2003, 17:12

-would there be a significant difference in quality compared to say feeding the satellite video via s-video or banana plug into the video card, and capturing using virtualdub?

Let me add (or expand on) one more point here.

3.5) S-video is analog and bandwidth limited. There is lots of noise introduced in the digital->analog and analog->digital steps doing this and most PC capture cards really don't do this all that well. So a pure digital capture path can have much better quality.

- Tom

kastro68

29th May 2003, 17:21

that cleared up a lot of uncertainty.
are there any dvb-S cards that you recommend? or features to look for in dvb-s cards?

how much would one of these cards normally cost? I checked some pricelists on the net, but they don't seem to list any dvb boards.

thanks again.

symonjfox

29th May 2003, 18:59

@ benf
mmm ... I don't know. I'm sorry.

@ Kastro 68

They don't cost a lot. I bought my board with 150€. But I found many other cards up to 350€. For example mine hasn't any Hardware MPEG2 decoder, so I must use Elecard codec (included) but it uses up to 70% of my CPU while watching.
Many other cards (hauppage) have many features that others don't have. I'm really annoyed from my board (VP 1030): has a very low quality on signal and drivers and programs doesn't work very well. It's ideal just for watching, but not for recording.

kastro68

29th May 2003, 20:13

http://www.ciao.co.uk/Hauppauge_WinTV_DVB_s__Review_5320150

Hi, I've been doing some research on dvb-s cards and came across this statement from the above article "So if you want to receive a DVB satellite signal (DVB is the European Digital standard, it is used all over the world execpt the US and Japan, a bit like NTSC) the WinTV-DVB-s is defenitly a must"

I live in Australia and was planning on getting free-to-air Japanese tv shows via satellite. If DVB is not used in Japan[or US], does that mean I can't capture japanese tv programs? Or is it the case that as long as I can watch it on tv, i can feed it into the DVB-s via LNB?

And for those interested about dvb-s cards, here is a link that i'm sure you'll find useful http://www.hauppauge.co.uk/html/digitaltv_prod.htm#dvbs

Edit: the second link above lists the Hauppauge dvb-s products. There were two boards...WinTV-Nexus-S and WinTV-Nova

Both cards have the same features, except:
- Nexus-s has Reception of DVB Data services (max Download speed 8 - 10Mbit/s)
- Nova has Reception of DVB Data services (max Download speed 40 Mbit/s)

If I were to capture free-to-air satellite shows, would this "reception" difference matter? eg. Would it affect the quality of the tv show? Logically I say it wouldn't, since it is digital. Does it only apply for using the satellite for downloading data, eg off the internet? I'm not planning on using the dvb-s card for anything other than watching/capturing satellite shows.

thanks

ronnylov

29th May 2003, 21:02

It seems that Japan use a digital TV system called ISDB-S for satellite and ISDB-T for terrestial digital TV. http://www.dibeg.org/PressR/ITU/ITU.htm

In USA, Taiwan and some other countries they use a system called ATSC. Hauppage has a PCI-card for ATSC capture.

In Europe and Asia DVB-S is the system they use.

I don't think a DVB-S card will work on ISDB or ATSC channels.

kastro68

30th May 2003, 08:23

@ronnylov

I read the link that you posted. But I don't even know what most of the acronyms meant. I don't even know what ITU means.

Does this mean I need a different satellite board other than a DVB-s if i want satellite channels from japan? Or is it a limitation of my satellite dish? Would I need a different board for different satellite broadcasting systems? eg one for ISDB-S, one for ATSC and one for DVB-S?

Thanks

benf2

30th May 2003, 13:14

@ronnylov

Do you recall any brands that offer the US sat. capture cards...I am having a terrible time trying to find anything. Hell, i would buy a TIVO if it would capture high def channels, but it doesnt.

There has to be a solution for people in the US to record to the Hard Drive and keep it digital without having to go analog 1st. like all-in-wonder, etc...

ronnylov

30th May 2003, 15:20

@kastro68
ITU is an international standardization organization. I can't say for sure that you can't receive japanese channels with a dvb-s board. Some channels may be sent on different systems like I can receive CNN also in Europe. Can you receive japanese channels with your satellite dish today? What kind of receiver is it, digital or analogue? I think the receiver part differs but you may still be able to use the same satellite dish.

@benf2
I found this link on Hauppage web site:
http://www.hauppauge.com/html/products.htm#digital
The WinTV-D is listed under "WinTV ATSC (U.S.) Digital TV receiver products". I'm not sure if it's a satellite, terrestial or cable receiver.

benf2

30th May 2003, 15:28

i will ck it out ...thanks

kastro68

30th May 2003, 17:25

Originally posted by ronnylov
@kastro68
Can you receive japanese channels with your satellite dish today? What kind of receiver is it, digital or analogue? I think the receiver part differs but you may still be able to use the same satellite dish.

The Satellite dish is set up for what is going to be my home in a few months... I haven't moved in yet. The seller told me the receiver was digital, it also had digital written on the box...I assumed that all satellite receivers were digital. The guy that sold it also flipped through some japanese channels at his store. My dad set up the dish, but I haven't had a chance to go look at it yet...maybe this Sunday.

What determines what channels you are able to receive via satellite? Is it the size of the dish, the direction the dish is pointing, elevation from the ground, or a combination of various other factors? Is it the receiver that determines what channels you can and can't watch?

thanks.

benf2

30th May 2003, 22:02

Well, i called tech support at Hauppage and apparently nothing on the market allows capturing in digital right from the sat recvr. It goes dig from the box to analog to the capture card and dig again to the hard drive. My Sat recvr has a DVI output...would be nice if a capture card allowed me to stream to it, so i can retain digital format quality.

kastro68

4th June 2003, 19:40

http://www.lyngsat.com/freetv/Japan.shtml

Apparently Japan does broadcast some programs via DVB.

Here is the list for FTA(free to air) south korean programs.

http://www.lyngsat.com/freetv/South-Korea.shtml

I just need to find out what the difference between c-band and ku-band is.

kastro68

6th June 2003, 22:25

Originally posted by benf2
Well, i called tech support at Hauppage and apparently nothing on the market allows capturing in digital right from the sat recvr. It goes dig from the box to analog to the capture card and dig again to the hard drive. My Sat recvr has a DVI output...would be nice if a capture card allowed me to stream to it, so i can retain digital format quality.

It might be possible to capture in digital if the DVB-S card allows you to connect directly to the LNB [low noise blockdownconverter] on the satellite dish.

I'm still not sure how the DVB-S cards work, since right now I'm reading up on Satellites, c-band footprints for the pacific region and how to use a compass.

Is the DVB-S card supposed to plug into the satellite receiver or directly to the LNB? I haven't got access to a DVB-S card just yet, so I can't check the ports.

Zhnujm

6th June 2003, 22:40

Originally posted by kastro68
Is the DVB-S card supposed to plug into the satellite receiver or directly to the LNB?
You connect it to the LNB, the card itself is a receiver. And you can of course capture digital with it.
(this is only for DVB cards, dont know about the other types)

kastro68

7th June 2003, 17:28

Originally posted by Zhnujm
You connect it to the LNB, the card itself is a receiver. And you can of course capture digital with it.
(this is only for DVB cards, dont know about the other types)

Thanks for clearing this up for me, because I wasn't sure.

Unfortunately for me, my LNB does not have dual output...this means I don't think I'll be getting a DVB-S card anytime soon since it would be a real hassle to unplug my dad's sat. receiver each time I need to cap. something.

I don't think I'll miss much...because my intentions for getting a DVB-S card was to capture DTH k-pop, j-pop MTVs and anime...BUT in australia only 2 korean channels are FTA and 1 is japanese. It's a shame that I don't live under the footprint of the Galaxy XR satellite (G10R), people in the Americas are really lucky.

Thanks again, you saved me from getting something that I prolly wouldn't have used.

joshyg2

5th August 2003, 17:55

Hi everyone,

I am very new to DVB and Digital Broadcasting, Im a bigger noob than kastro68. I too live in Australia.

Im don't know how you actually recieve channels, I thought you need a SmartCard to give you access. How can you recieve channels using a DVB card? Can you access any channels with a DVB card?

kastro68 if your planning to buy a card, or get a Satallite installed I found a company that will do it in Australia:

http://www.skyfox.com.au/
http://www.skyfox.com.au/pcsatcard.html

oh and another thing,

The Hauppauge WinTV NOVA-CI has a CI slot, what is it?

ronnylov

5th August 2003, 18:02

The CI slot is where you insert your Common Interface module and then you insert your smartcard into the CI module to decrypt your subscribed channels. So you will need a CI module that works with your smartcard.

auenf

8th August 2003, 16:43

Originally posted by joshyg2
Hi everyone,

I am very new to DVB and Digital Broadcasting, Im a bigger noob than kastro68. I too live in Australia.

Im don't know how you actually recieve channels, I thought you need a SmartCard to give you access. How can you recieve channels using a DVB card? Can you access any channels with a DVB card?

kastro68 if your planning to buy a card, or get a Satallite installed I found a company that will do it in Australia:

http://www.skyfox.com.au/
http://www.skyfox.com.au/pcsatcard.html

oh and another thing,

The Hauppauge WinTV NOVA-CI has a CI slot, what is it?

you may as well get a DVB-t card and hook it up to your current analogue aerial (which is what ive done, and if you look on the 3rd page of the enterprise thread, youll proably start drooling ;)

Enf...

joshyg2

13th August 2003, 02:16

yeah, but I don't wanna just recieve free to air channels. Im not gonna spend $300 on a card and just watch 5 channels.

if im gonna spend the money, im gonna spend more and get a satallite dish, a Hauppauge NOVA-CI DVB-S card and get a smartcard that will allow me to recieve all the pay channels, MTV, V, etc.

Joe Fenton

26th August 2003, 05:16

Well, I don't know about Europe or Japan, but here in the US, digital broadcast is all basically the same.

You start with DVD - MPEG2 Video and AC3 audio are your two main streams, together with a program stream and maybe some other streams like subtitles. The data stream may or may not be encrypted.

HDTV - broadcast HDTV in the US uses ATSC, but all that is is DVD data passed through a trellis encoder combined with a psuedo-randomizer. The trellis encoding/randomizer simply spreads the transmitted frequencies a bit more evenly for a better signal to noise ratio at the receiver. All a DVB-T card is is a trellis decoder with a stage to remove the psuedo-random value followed by standard DVD circuit.

DVB-S/DVB-C. The EXACT same circuitry. The only difference is the frequency of the IF stage going to the tuner. After that, it is the same circuitry as the DVB-T/DVD. The audio is usually PCM instead of AC3. Otherwise, the data is the same as a DVD. Of course, some DVDs use PCM audio too.

All encryption removal occurs in the chip that decodes each of the elementary streams. LSI makes the chips mentioned above, as do others like Motorola. A card is like this:

HDTV: Tuner -> Trellis -> Transport (stream demux) -> MPEG2 / AC3

DVB-S: Tuner -> Transport -> MPEG2 / PCM

DVB-C: Tuner -> Transport -> MPEG2 / PCM

DVD: DVD read -> Transport -> MPEG2 / AC3(PCM)

The same set of chips is used for the same named stages. The only difference is in the programming of the embedded CPU that is part of the Transport chip. This is usually a MIPS-II RISC CPU in the current LSI chipsets. This is the chipset you'll find in all Echostar (Dish Network) receiver boxes.

This makes it cheap for the companies involved since everything is standardized. Then they can gouge the customer while spouting some babble about needing sophisticated digital processing. :rolleyes:

If you had enough skill at making PC cards, you could make your own card that handled DVB-T, DVB-S, and DVB-C. The thing is, American companies don't want you doing that. You have to buy THEIR equipment and THEIR expensive services. If you were experienced enough with the encryption schemes used by satellite and cable companies, you wouldn't even need a smart card. BTW, the smart card is accessed by the Transport chip. It usually has a "standard smart card" interface.

Shameless1

28th August 2003, 02:55

Some cards, like the VisionPlus 1020 have a cable pass through. So you can connect the LNBF to the card, then connect the card to the set top reciever. The card has a relay that will pass through the signal until you use the card, then it takes the signal and the other reciever does not get a signal.

So you can use both, but not at the same time.

Shameless.

gnivler

16th September 2003, 13:17

[QUOTE]Originally posted by Joe Fenton

<snip>

All encryption removal occurs in the chip that decodes each of the elementary streams. LSI makes the chips mentioned above, as do others like Motorola. A card is like this:

HDTV: Tuner -> Trellis -> Transport (stream demux) -> MPEG2 / AC3

DVB-S: Tuner -> Transport -> MPEG2 / PCM

DVB-C: Tuner -> Transport -> MPEG2 / PCM

DVD: DVD read -> Transport -> MPEG2 / AC3(PCM)

My goal is to capture HDTV losslessly (at worst near-lossless) from the broadcast format; I have been working on the assumption I need a capture card which is capable of high resolutions (like 1920x1080); having read this now am I correct that a DVB-S card will capture the PS intact regardless of it's resolution? The end result being an MPEG2 file (at the broadcast resolution/format) with demuxed AC3 stream? And, if so would that MPEG2 file be usable in an avisynth script using mpeg2source() (and the mpeg2dec3.dll plugin)?

Edit: My source would be a pay service (Starchoice) so not ATSC/OTA I guess.

The software relating to capturing and viewing is also not clear to me; which ones are used, if capturing and preview/normal viewing is simultaneously possible - box is 2ghz Athlon XP w/ 1024mb DDR400 CAS2 and a 8mb ATA133 160gb dump drive.

I'm reading everything I can find but am still not understanding something about my goal. For instance there doesn't seem to exist an HD DVB-S card per-se...

Any info would be much appreciated, tia :D