The Official 169time AVX-1 Technical Status Discussion - Page 102

I dont think there will be any problem for both 169time or the 5000 HD guys to come up with a Mpeg 4 solution.

Until we see the new hardware no one knows if it will allow the access points to allow the modification. Any claims from ether camp this early on is pure speculation.

Hopefully we still have a years worth of recording left with our current setup.

Yes i have no doubt that the guys will come up with mpeg4 mods but what the heck will we playback everything on, i am assuming that i am screwed with my DVHS setup

I'm not to worried about E*, it is gonna take them a few years by that time Blu-ray should be going very well and may be able to record and playback mpeg4???

-Gary

Also John, both my 5u's acted the very same way with my 169time E* 6000, neither 5u would see the HDVR in my Dish 6000,

After much trouble Richard finally suggested i may have a much older firmware that was not able to work with the 5u or 40k for that matter

well i did end up having a old firmware, 1.8 to be exact, my board is on it's way to Richard right now to be updated to 1.86, i betcha that will solve all my troubles, i will report, that will probably be your fix also

-Gary

169time has a firewire upgraded prototype receiver with mpeg4 decoding working in their lab. We're ready for the mpeg4 transition, but there are no mpeg4 transmissions for subscribed boxes.

Personally I think the mpeg4 announcements are more to pacify the bean counters that are concerned about the continued subsidizing of unprofitable HDTV distribution by profitable SD distribution. Paying respect to the painfully slow historical progress for HDTV equipment deployment, there is some reason for me to think we won't be seeing widespread or universal mpeg4-only HD Satellite transmission for a quite a long while.

169time invented HDTV recording upgrades, and beat the copycats by four years. Information about the 169time mpeg4 upgrade prototype is confidential and well guarded for many obvious reasons.

When mpeg4 happens, 169time customers will be ready first. Here's how- For new purchasers of 169time upgrades, 169time guarantees to apply 50% of the purchase price for upgrades toward the initial release of the mpeg4 box upgrade solution. The 50% discount will be given in exchange for the HDVR board (current upgrade) purchased now. In the case of purchasing a complete upgraded box from 169time, the 50% is based on the upgrade price, not the whole box price. The offer applies to upgrades or upgraded boxes purchased from 169time starting 2/1/05 and until further notice.

On a different subject, a hard drive based AVX1 was actually working in the 169time lab back in 2001 before we started shipping the unit that supported tape based recording. 169time will ship a Linux based DVR that includes the AVX-1 function when its user interface features are ready.

Good news Richard but mpeg4 basically makes all our dvhs decks paper weights right???

-Gary

Since a D-VHS deck is just a bit bucket, you should be able to record the MPEG4 stream. You'll need to a stand alone MPEG4 decoder with firewire in order to view them.

The Firewire interface to the JVC DVHS decks accepts as input MPEG-2 transport streams such as a camcorder DV stream. Therefore it will not work with an MPEG-4 stream - that stream would have to be converted to a MPEG-2 transport stream to be recorded by the DVHS recorder.

bwooster, are you sure? It certainly won't play them back, but I don't see any indication that it wouldn't record them for playback through an external firewire device.

Don't the DVHS decks record the incoming signal with mpeg2 at 28 Mbps??

I think we are screwed with mpeg4 and dvhs decks

Jvc would have go back to the drawing board and release a compatible unit

oh well i'm not worried, mpeg4 is a while off for me with E*

-Gary

The ~ 28 Mbps standard is a proprietary JVC DTheater thing. The JVC decks can play them back but I am not sure that the chipset in them supports writing them onto a DVHS tape.

ATSC MPEG-2 transport streams (that follow the MPEG spec) are at most ~ 19 Mbps.

I was speaking of the recording speed in HS mode which is mpeg2 28 Mbps correct??

-Gary

Buzzz XXX

Wrong. There are already specifications that outline how to carry Mpeg-4 video and audio on an Mpeg-2 transport stream. The iso 13818-1 (mpeg2 systems) spec is very flexible. The jvc would have no problem recording a transport stream that includes mpeg-4. As a previous poster stated, the Jvc would require a PC or STB that supports mpeg-4 playback. I have it on good authority that both 169time and the R5000 guys have been able to record and playback HD mpeg-4 to JVC/Mitsubishi DVHS deck.

Techtom

MPEG-2 Transport streams vary in the rate at which data is streamed from them. The max data rate is about 19.2 Mbps. Some of the data in the transport stream has nothing to do with the video / audio such as the channel of the station that you are watching. Some transport streams have more than one program in them. For example, if I record ABCs HD channel (7.1 in my area) I also get a standard definition channel (7.2) with the transport stream. If I play the tape back on my deck I can switch between which program from the transport stream that I wish to watch.

Some of the packets in a transport stream can be "null" packets that contain no information but are used to say, maintain a constant stream rate.

Some transport streams are much less than 19.2 Mbps and this can result in varying HD quality.

You can buy documents from the ISO that detail the MPEG standards. Another good book is "Digital Television Fundamentals".

This is getting really off-topic so I will try to summarize things a bit. From ISO/IEC 13818, "Generic coding of moving pictures and associated audio information: Systems", page xi,

"The Transport Stream is a stream definition which is tailored for communication or storing one or more programs of coded data according to ITU-T Rec. H.262 | ISO/IEC 13818-2 and ISO/IEC 13818-3 and other data in environments in which significant errors may occur."

"Tranport streams may be fixed or variable rate."

Lower on the page it says, "several operations on a Transport Stream are possible with minimum effort. Among these are..."

One of the listed operations is extracting a program from the tranport stream and producing a differemt output stream, for example a "program stream" (DVDs use MPEG-2 Program Streams which are for environments where errors are unlikely).

So for example, my DVHS deck records the ABC transport stream but then the decoder can extract one program, say the HD one, and then let me watch it (or I can watch the SD one).

Now the data in the transport stream must be decoded by the JVC deck. It has to take the packets in the stream that belong to the program that you wish to watch and then use the packets to construct a block of data that belongs to say audio, or video. That data must conform to the ISO specs and the hardware and software in the deck must be able to decode it and then present it to say the component outputs or digital audio output. The deck can ignore data it does not understand - for example, the early JVC decks did not work with DTS data in transport streams. You can play a DTS DTheater tape in these older decks, but they won't know what to do with the DTS data packets and so will ignore them.

Now MPEG-4 is designed to build on the work of MPEG-2. I have not finished reading it but you can look at, "The MPEG-4 Book" which is a great reference. Look at page 268 at section 7.4 "Transporting MPEG-4 Over MPEG-2". On page 274 it states, "transport over MPEG-2 Systems of isolated MPEG-4 elementary streams is limited to streams that do not realy on MPEG-4 System functionality - this means audio and video streams".

What this all means is that you CAN embed MPEG-4 audio and video into an MPEG-2 streams. The problem is that you need an MPEG-4 decoder to play them back properly.

So what you can do is the following:

1) modify a satellite box to get access to the MPEG-4 stream
2) isolate the MPEG-4 audio and video and then encode it into a valid MPEG-2 stream
3) record the MPEG-2 stream with your DVHS deck
4) when you playback the MPEG-2 stream you need to extract the MPEG-4 audio and video from the stream and then play it back - current DVHS decks cannot do this

OR you can

1) modify a satellite box to get access to the MPEG-4 stream
2) isolate the MPEG-4 audio and video and then re-encode it into MPEG-2 stream audio and video in a format that your deck CAN decode
3) record the MPEG-2 stream with your DVHS deck
4) playback the MPEG-2 stream from your deck

Now this isn't an easy process and remember that MPEG-4 is NOT just about audio and video. The MPEG-2 streams cannot transport data that relies on MPEG-4 System functionality.

bwooster, have you tried it? I ask because supposedly others have and it works.

as for real-time transcoding of MPEG4 to MPEG2, that isn't going to happen

To madpoet: Have I tried what?

Do you mean have I hooked up a satellite box that outputs a MPEG-4 stream to a DVHS deck and seen if it can record it?

I don't have such a satellite box - I am not even sure if one exists.

VOOM was supposed to be using MPEG-4 audio and video encoding. The VOOM boxes may be embedding their MPEG-4 audio and video in an MPEG-2 stream. I don't know.

Do the VOOM boxes even have Firewire outputs to connect to a DVHS deck? Can they be modified to do it? I don't know.

Do the VOOM boxes have a firewire input so that the DVHS decks could playback a stream to them? I don't know.

Can DVHS decks playback MPEG-4 encoded audio and video? No - they are not built for that.

Nope, have you tried some method of recording existing mpeg4 to DVHS. Voom does not have firewire and cannot be modified for it (plus they aren't using MPEG4 yet anyway). I'm just saying, you're arguing that it can't work when people who createit seem to indicate it can

Please reread my rather long post from before.

I am not arguing that it cannot work. In fact, as I stated, the MPEG-4 standard was DESIGNED with some backward compatibility in mind, just as the MPEG-2 standard was DESIGNED to allow for future expansion (such as the addition of DTS audio to transport streams).

Clearly MPEG-4 audio and video CAN be encoded in an MPEG-2 transport stream. MPEG-4 features that rely on the MPEG-4 Systems functionality CANNOT be encoded into an MPEG-2 transport stream.

But your DVHS deck does not decode MPEG-4 audio or video data.

I will restate the above sentence again to make sure that you read it properly.

Your DVHS deck does not decode MPEG-4 audio or video data.

Now it could store / ignore the data. For example, play a DTS DTheater tape in an old DVHS deck. You won't get a DTS audio stream out of the deck - it does not know how to deal with the DTS data in the transport stream.

I did NOT say that Voom was using MPEG-4. Please read my previous posts carefully. I DID say that they were "supposed to be using MPEG-4 audio and video encoding."

Where did I get this idea from? Why from the Voom press release on the subject! You can read it at:

<<a href="http://www.voom.com/util/press/press_112204_print.shtml" target="_blank">http://www.voom.com/util/press/press_112204_print.shtml>

In particular:

"Mr. Dolan explained that all the programming transmitted by both Rainbow 1 and Rainbow 2 will utilize a new encoding system from Harmonic, initially configured to run in MPEG-2 and software upgradeable to MPEG-4.

"Today's announcement is a step forward in our plans to advance VOOM to MPEG-4 later in 2005. All VOOM customers have been provided with set-top boxes capable of receiving the MPEG-4 signal and we remain committed to offering more than 400 full continental US channels before the end of 2005," continued Mr. Dolan. "

I don't know if Voom made the transition to MPEG-4 but if they did then you can certainly try to get access to it and then record it using your DVHS deck.

Now you wrote, "you're arguing that it can't work when people who createit seem to indicate it can."

Can you please elaborate on that? Who are these "people"? What is the source of the MPEG-4 stream? Was it just the audio and video that was recorded? How was the stream accessed? How was it output? As an MPEG-2 transport stream over firewire into a DVHS deck? Could the DVHS deck play any of the MPEG-4 data?

Now I CAN tell you a way of testing the playback of MPEG-4 audio and video from a DVHS deck but I think this discussion is getting way off topic. If you have read what I wrote before then you already know how to do the test.

Good luck to you in your efforts.

You said:

"The VOOM boxes may be embedding their MPEG-4 audio and video in an MPEG-2 stream. I don't know."

So I answered and explained they weren't. I never claimed you said they were, and you're getting a little too testy about this. I asked a legitimate question.

You also said:

"The Firewire interface to the JVC DVHS decks accepts as input MPEG-2 transport streams such as a camcorder DV stream. Therefore it will not work with an MPEG-4 stream - that stream would have to be converted to a MPEG-2 transport stream to be recorded by the DVHS recorder."

THis is the part that myself (and others) are questioning. You are stating your opinion as theoretical certainties, but there seems to be some serious debate about whether you are correct. So I asked a legitimate question... have you tried it? It's been stated (correctly) more than once that DVHS is a bit bucket. Are you sure that it will not simply function as a bit bucket for an MPEG4 stream? THat's all I'm asking.

You can use DVHS decks to back up computer files, so certainly it will back up MPEG-4 streams.

Gee I didn't think I have been getting testy. I think I have been rather polite. Read my previous posts and you will see several uses of the word "please".

Can you please explain what you mean when you say that the DVHS deck is a "bit bucket"?

As a programmer I know what "bit bucket" means but I am sure that you must mean something else than what a programmer means by the term.

Here is the definition from Wikipedia.org:

Bit Bucket:

From Wikipedia, the free encyclopedia.

The bit bucket was the container on Teletype machines or IBM key punch machines into which chad from the paper tape punch or card punch was deposited. In theory, the bit bucket was full of '1' bits, the '0' bits being represented by the places on the paper tape or punched card that the punch had not punched out.

The term was then generalized into any place where useless bits go including the trash can or rubbish bin. In Unix, this term is used to refer to /dev/null. In OpenVMS, this term refers to SYS$NULL:.

The term is also used to refer to that mysterious place on a computer where lost documents go, as in:

"What happened to that important spreadsheet that you were just editing?"

"Oh, it went into the bit bucket."

I feel certain that you must mean something else by your use of the term.

To madpoet:

Please look at the JVC HM-DH30000U manual (you can download it from the web) and read the specifications of the device from page 81. For video format it says "MPEG2 standard". For audio format it says "Encode MPEG1 Layer2", "Decode MPEG1 Layer2" and "Dolby Digital".

The device knows nothing about using MPEG-4 video or audio.

Please now turn to the HM-DH5U manual on page 89 and check out its specifications. For Video format it says "MPEG2 standard". For audio it says "Encode MPEG1 Layer2", "Decode MPEG1 Layer2/Dolby Digital" and "Linear PCM".

The device knows nothing about using MPEG-4 video or audio.

I have to ask you once again...please tell us who has been able to record and playback MPEG-4 audio / video streams from a DVHS deck without any additional hardware.

Thank you Compromise for reading what I have been writing!

Yes you certainly CAN back data up using a DVHS recorder. You have to be very careful though.

Why? Because the DVHS tape stores MPEG-2 transport streams. These streams were designed to be used in an environment where packet loss is expected. The deck may not give you back the exact stream that you stored on it. So you have to add some layer of data duplication / checking summing / protection on top of the transport stream layer.

madpoet: I hope that Compromise and I have answered your question about storing MPEG-4 audio / video in an MPEG-2 transport stream. It CAN be done and it was DESIGNED to be doable (see "The MPEG-4 Book" for more on this).

The JVC DVHS decks store MPEG-2 transport streams. They CANNOT decode MPEG-4 audio or video data. Please check out the specifications in the DVHS manuals.

Now if you wanted to test the decks it is really easy. Grab an MPEG-4 file, say a music file like an AAC file. Embed it into an MPEG-2 transport stream and then record it onto a DVHS tape. Then play back the tape....you will hear....silence. The deck had no idea of how to decode the MPEG-4 audio so it just ignored it.

Now hook that DVHS deck up to your Macintosh and download the MPEG-2 stream onto your computer. Use software to extract the MPEG-4 AAC data from the MPEG-2 stream (this is really easy to do) and save it in a file. Play that file with QuickTime Player, iTunes or VLC and you will hear...music!

Do you get it now madpoet? You CAN record MPEG-4 audio and video data encoded in an MPEG-2 stream to a DVHS deck. You just can't get the deck to play it back.

I have to ask you once again...please tell us who has been able to record and playback MPEG-4 audio / video streams from a DVHS deck without any additional hardware.

I also believe you cannot play MPEG-4 back obviously as the decks do not have MPEG-4 decoders, however you can READ it back.

so where in business with say my 5u connected to a outbard device via firewire with a mpeg4 decoder, then the ouboard device with mpeg4 decoder would connect to the display, like for example the LG HDTV PVR if it had a mpeg4 decoder

-Gary

Bwooster,
What I and other on this list are objecting to is your initial incorrect statement:


Note that you said "recorded".

Now you are changing your argument:




By your definition, the Mitsubishi DVHS deck would fail to playback mpeg-2 because it requires "additional hardware", specifically the samsung SIR-T165 external firewire set top box.

The point is that MPEG-4 (AVC and AAC) elementary streams when properly encapsulated in an mpeg-2 transport stream can be recorded on a DVHS deck. To Playback a mpeg-4 recorded on a DVHS deck, and external mpeg-4 decoder is required.

No commercial external decoders with mpeg-4 and firewire are currently available, but there are prototypes in the works...


So don't Ebay that DVHS deck just yet...

Techtom

Thanks Tom, maybe he'll listen to you .

Techtom:

I said (as quoted by you):

>
The Firewire interface to the JVC DVHS decks accepts as input MPEG-2 transport streams such as a camcorder DV stream. Therefore it will not work with an MPEG-4 stream - that stream would have to be converted to a MPEG-2 transport stream to be recorded by the DVHS recorder.
>

This IS ABSOLUTELY CORRECT. Please read what I wrote. The DVHS decks do NOT work with MPEG-4 streams. MPEG-4 audio and video streams CAN be encoded in MPEG-2 transport streams and then recorded any played back by a deck. If there is something wrong with this statement then please explain it to me.

Also Techtom you said:

>
No commercial external decoders with mpeg-4 and firewire are currently available, but there are prototypes in the works...
<<br />
There is already a computer that comes with the capability to decode and playback MPEG-2 and MPEG-4 streams. It may already be able to playback MPEG-2 sterams with MPEG-4 audio and video data in it. If not then it should be easy to modify it to playback these streams. If you wish I can point you to the software and even the source code for it. The compiler and source code are free software so you can use them as you wish. This computer comes i several models and some have DVI and a digital audio output that can be hooked up to your AV equipment.

Nice to see you on here Richard!

Don't forget DirecTV's management changed fairly recently (now NewsCorp, also parent co. of FoxNews). They appear to embrace a slightly more proactive business model. One might even assume embracing Mpeg4 before most everybody else is 'out of character' with the plodding DirecTV we have all known and come to love for so long...

Just trying to suggest the 'painfully slow historical progress' might be a thing of the past (no pun intended). Please beware of hasty assumptions it'll be years before we see anything new; just the competition will keep a fire under their butts...

Thanks for all the heads-up work you HAVE done...

Two weeks ago I recorded the playoff game between New England and Pittsburgh,using jvc30000 and the new software without a problem. Tonight I recorded the Super Bowl and had no sound and major video problems. My settings were correct and the HS appeared to be working. I did not observe the flashing auto and HS. My tape seems to be worthless. I am very upset that the one event I wanted to have was a total failure