How-To: MacOS X Firewire HDTV recording - Page 10 - AVS Forum
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post #271 of 2181 Old 04-11-2004, 11:45 AM
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Don't know what I did but I have audio now in VLC! Heh. Life on the bleeding edge eh? FWIW I popped over to the office to check out WinDVD and see if it would play my HBO file but it says invalid file format - as mentioned earlier I can't play it on the Mac either. I did rename the files from the .m2t format to .trp. The INHD file works fine - just like on the Mac as with all the non-premium movie channels.

I guess I'll touch base with my Mac contact at Comcast and see what he has to say. I've read that the Moto 620x on Comcast can record pay movie channels, so it must be something about the STB. Quote below from the Comcast Firewire Moto 620X thread:
Quote:


I haven't come across any obvious limitations when it comes to recording. I get all the premium HD channels here and they all come in over firewire and as is apparent from other people, play back without a hitch.


Dave Cook
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post #272 of 2181 Old 04-11-2004, 12:10 PM
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Quote:


Originally posted by FriarWyer
That indeed is a strange problem. Sounds like a potential bug in the 6200's firmware.

You can try:

Channel up (key release state) would be:

00487C3000

Channel down (key release state) would be:

00487C3100

FriarWyer,

Thanks! It worked as advertised!

Regards,
Joe


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post #273 of 2181 Old 04-11-2004, 01:06 PM - Thread Starter
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Originally posted by jsb_hburg
FriarWyer,

Thanks! It worked as advertised!

Joe so sending "00487C3000" changes the channel up 1 and "00487C3000" changes the channel down 1 on your Moto? It does nothing on my SA box and returns "Not Implemented". I assume you'll use this as a workaround to change to say 190 by first changing to 189 with command "00487C670400BDFFFF" and then sending "00487C3000" to go up 1 to 190.

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post #274 of 2181 Old 04-11-2004, 01:19 PM
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Quote:


Originally posted by rcliff
Joe so sending "00487C3000" changes the channel up 1 and "00487C3000" changes the channel down 1 on your Moto? It does nothing on my SA box and returns "Not Implemented". I assume you'll use this as a workaround to change to say 190 by first changing to 189 with command "00487C670400BDFFFF" and then sending "00487C3000" to go up 1 to 190.

Cliff,

I sent 00487C30000000FFFF to channel up one time and 00487C31000000FFFF to channel down one time. I think the SA implementation of FireWire is flawed for the moment.

Regards,
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post #275 of 2181 Old 04-11-2004, 01:28 PM
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I sent 00487C30000000FFFF to channel up one time and 00487C31000000FFFF to channel down one time. I think the SA implementation of FireWire is flawed for the moment.

The correct format of the command packet is only 487C3000, not 00487C30000000FFFF. The 0 after the 30 specifies how many additional operation_id specific bytes follow. For chan-up, and chan-down operation_ids, there are no additional operation_id specific bytes.
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post #276 of 2181 Old 04-11-2004, 01:37 PM
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Originally posted by FriarWyer
The correct format of the command packet is only 487C3000, not 00487C30000000FFFF. The 0 after the 30 specifies how many additional operation_id specific bytes follow. For chan-up, and chan-down operation_ids, there are no additional operation_id specific bytes.

I used 00487C3000 and 00487C3100 and they work exactly as advertised! Thanks again! It's faster by a second. I was wrong about having to backfill the rest of the command with 0s and Fs. I saw errors without the leading 00.

Regards,
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post #277 of 2181 Old 04-11-2004, 02:31 PM
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While watching the 'Sox and 'Jays today I noticed that the video I capture with my G5 has MUCH more field of view than my TV in "Natural" mode which is what I have to use for HDTV. Does anyone know how I can adjust this on my TV?

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post #278 of 2181 Old 04-11-2004, 02:48 PM
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Originally posted by Cooknn
While watching the 'Sox and 'Jays today I noticed that the video I capture with my G5 has MUCH more field of view than my TV in "Natural" mode which is what I have to use for HDTV. Look at all the picture I'm missing! http://www.ftmyers.com/yikes.jpg Apparently I'm not alone according to a post over at www.hdtvoice.com.

The area outside the lines is what my Mac captures over the Firewire and the area inside the lines is what I am seeing on my Toshiba TheaterwideHD. Does anyone know how I can adjust this on my TV?

This is overscan. On my DLP, I see the full picture over DVI since there is very little if any overscan. A calibrator or a very experienced service tech can adjust the overscan. Over component, it is about 5%. It can be dialed back so you can see the full picture as much as possible.

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post #279 of 2181 Old 04-11-2004, 03:42 PM
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Quote:


Originally posted by jsb_hburg
A calibrator or a very experienced service tech can adjust the overscan. Over component, it is about 5%. It can be dialed back so you can see the full picture as much as possible.

Thanks for the heads up. I bought the extended on-site warranty with Best Buy so I'll try my luck at getting a tech over here to adjust it. Damn that's a lot of extra real estate

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post #280 of 2181 Old 04-11-2004, 03:59 PM - Thread Starter
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Quote:


Originally posted by Cooknn
Thanks for the heads up. I bought the extended on-site warranty with Best Buy so I'll try my luck at getting a tech over here to adjust it. Damn that's a lot of extra real estate

Good luck with best buy tech I would be shocked if they do anything for you if your set is actually working. There is no way they will adjust the set for overscan based on a warranty claim if the set is operating within factory specs. You need an ISF calibrator to work on your RPTV and not only will you end up with less overscan but a properly calibrated display.

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post #281 of 2181 Old 04-11-2004, 06:20 PM
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Quote:


Originally posted by rcliff
Joe so sending "00487C3000" changes the channel up 1 and "00487C3000" changes the channel down 1 on your Moto? It does nothing on my SA box and returns "Not Implemented". I assume you'll use this as a workaround to change to say 190 by first changing to 189 with command "00487C670400BDFFFF" and then sending "00487C3000" to go up 1 to 190.

Here is the log for channel up...

Code:
=============== Sent AVC Command ===============
cType:   Control
subUnit: 0x48
opCode:  Unknown (0x7C)
FCP Command Frame:
00 48 7C 30 00 

=============== Received AVC Response ===============
response: Accepted
subUnit: 0x48
opCode:  Unknown (0x7C)
FCP Response Frame:
09 48 7C 30 00

Regards,
Joe


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post #282 of 2181 Old 04-11-2004, 06:53 PM - Thread Starter
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Quote:


Originally posted by jsb_hburg
Here is the log for channel up...

Code:
=============== Sent AVC Command ===============
cType:   Control
subUnit: 0x48
opCode:  Unknown (0x7C)
FCP Command Frame:
00 48 7C 30 00 

=============== Received AVC Response ===============
response: Accepted
subUnit: 0x48
opCode:  Unknown (0x7C)
FCP Response Frame:
09 48 7C 30 00

I get the identical log except I receive "response: Not Implemented". I get the same results on the SA box, the Sony Box, and Mits RPTV. It seems your Moto box has more AV/C control properly implemented.

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post #283 of 2181 Old 04-11-2004, 10:47 PM
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Originally posted by rcliff
Good luck with best buy tech I would be shocked if they do anything for you if your set is actually working. There is no way they will adjust the set for overscan based on a warranty claim if the set is operating within factory specs. You need an ISF calibrator to work on your RPTV and not only will you end up with less overscan but a properly calibrated display.

I want to add that you will never be able to completely eliminate overscan. The edges start to bow and warp at a certain point. And it's not necessarily desirable anyway since most things get filmed with overscan taken into account... and the overscan allows a 1.85:1 image to fill your screen without black bars.

Your target would be between 5% to 10% overscan. I'd call 5% very low, and 10% a bit high. You can do this yourself if you can get into the service menus, and have a disk that shows geometry patterns on your screen (Avia / Video Essentials).

-Pie

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post #284 of 2181 Old 04-12-2004, 06:36 AM
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Quote:


Originally posted by FriarWyer
I'm pretty sure I know what is going on here. It was recently reported to Apple's FireWire developer mailing list that using VirtualDVHS on a system with the older PCI-Lynx type FireWire link chip causes the system to kernel-panic. The G3 B&W system uses PCI-Lynx instead of the more modern OHCI that is in all recent systems.

This is due to how the FireWireMPEG.framework initializes the DCL program in the MPEG2Receiver object.

For now, I'd suggest that you install a OHCI FireWire card into one of the PCI slots in the system, and connect your STB or HDTV to that card instead.

VirtualDVHS will always detect and use a FireWire card in a PCI slot, instead of the built-in FireWire.

Additionally, I'll look to see if I can suggest a simple code change to the MPEG2Receiver.cpp that could work-around this known bug (now that root cause has been established).

This problem should be addressed in a future OS update.

Well I am almost ready to give up on this... I also installed Jaguar, the SDK and the Pre-Release Firewire Components and I still cant get this to work... the good news is on Jaguar the whole system don't crash just Virtual DVHS.

I also tried using the Belkin PCI Firewire card from my PC with both Jaguar & Panther and got the same results.

Quote:


Originally posted by rcliff
dlan, please excuse the request for all of this but quite often this points to a simple solution that may have been overlooked. I don't see a glaring problem with your config and it should work as far as I can tell yet I don't know of anyone else that has done this specifically with a B&W G3. I may be able to get a hold of a B&W G3 to test on Monday.

Cliff,
Is there any chance you will be able to test this on a B&W anytime this week?
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post #285 of 2181 Old 04-12-2004, 07:10 AM
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Originally posted by Cooknn
While watching the 'Sox and 'Jays today I noticed that the video I capture with my G5 has MUCH more field of view than my TV in "Natural" mode which is what I have to use for HDTV. Look at all the picture I'm missing! http://www.ftmyers.com/yikes.jpg Apparently I'm not alone according to a post over at www.hdtvoice.com.

Sorry to hear about your overscan problem. I have asked, how did make the .jpg ? It looks great ! I am new to Macs and I assume it is very easy but would appreciate knowing.

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post #286 of 2181 Old 04-12-2004, 07:53 AM
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Quote:


Originally posted by Killroy
...

I would also recommend the first generation iMac and I have seen them for less than $400 around town. The first generations were a bit easier to upgrade the hard drive but nothing else. And if you add a multi-bay firewire enclosure, you will have a pretty inexpensive system.

As for the early iMacs, make sure it has FireWire. It should have a DV designation. My first "iMac" did not have FireWire. A cheap, used eMac would be a good recording set up. An outboard MPEG2-TS decoder with FireWire would be needed for playback, however.

Regards,
Joe


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post #287 of 2181 Old 04-12-2004, 10:52 AM
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Yeah, well, when I first saw this thread (actually, the first AV/C Mac thread), I was REALLY excited because I figured that a G4 cube would be PERFECT for this for us. Our t165 is in the bedroom, so a fanless (headless) small box would be ideal, and I figured since the last selling price of a new cube was under $1k, they'd HAVE to have come down a lot in price. Right? Yeah, go look at eBay.

Refurbished ones sell for more than the $999 price I thought about buying one for a few years ago.

With that said, I'm pretty enthused about the result of my first real test recording to my TiBook. Playback is fine (from a 720p signal - Alias last night) on the t165 and on my 1Ghz TiBook in VLC, if I mess with interlacing and use "discard". A clip from the Patriot looked great too. I'm such a fan of this. Thanks for the help. My only issue is that I couldn't get my external 2.5" bus powered FW drive into the mix with the single FW bus.

I'm sure I'd pay $99 or perhaps more for a software PVR product based on this. Someone's GOT to be working on this somewhere.
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post #288 of 2181 Old 04-12-2004, 12:23 PM - Thread Starter
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Originally posted by bakerzdosen
I was REALLY excited because I figured that a G4 cube would be PERFECT for this for us. Our t165 is in the bedroom, so a fanless (headless) small box would be ideal, and I figured since the last selling price of a new cube was under $1k, they'd HAVE to have come down a lot in price. Right? Yeah, go look at eBay.

Refurbished ones sell for more than the $999 price I thought about buying one for a few years ago.

The cube has become somewhat of a collectors item. It was a great little box but was only built for less than 1 year before it was axed.

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post #289 of 2181 Old 04-12-2004, 02:38 PM - Thread Starter
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Quote:


Originally posted by dlan
Cliff, is there any chance you will be able to test this on a B&W anytime this week?

Looks like the B/W I had in mind is in use with OS9. The fact that Killroy seems to have had the same problem as you is not very encouraging. It may be worth reporting this to Apple as the B/W is still officially supported under Panther and should not be generating Kernel panics with the new AV/C firewire components. I also would have thought a PCI firewire card would have resolved this.

Did you try the standard Mac troubleshooting? Zap Pram, reset CUDA, PMU, etc? What kind of firewire card are you using?

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post #290 of 2181 Old 04-12-2004, 03:01 PM
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Quote:


Originally posted by dozens
Sorry to hear about your overscan problem. I have asked, how did make the .jpg ? It looks great ! I am new to Macs and I assume it is very easy but would appreciate knowing.

While playing the file fullscreen on VLC, press Apple-Shift-3 to create a screenshot PDF. You can then export to a JPG file using Preview.

Regards,
Joe


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post #291 of 2181 Old 04-12-2004, 03:22 PM
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Originally posted by rcliff
Looks like the B/W I had in mind is in use with OS9. The fact that Killroy seems to have had the same problem as you is not very encouraging. It may be worth reporting this to Apple as the B/W is still officially supported under Panther and should not be generating Kernel panics with the new AV/C firewire components. I also would have thought a PCI firewire card would have resolved this.

Did you try the standard Mac troubleshooting? Zap Pram, reset CUDA, PMU, etc? What kind of firewire card are you using?

I don't even know what these tools are.
I am using this Belkin Firewire card
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post #292 of 2181 Old 04-12-2004, 05:15 PM - Thread Starter
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Quote:


Originally posted by dlan
I don't even know what these tools are.
I am using this Belkin Firewire card

To zap pram turn off your Mac and then restart holding the 4 keys "command(apple)-option-P-R" all simultaneously and hold until the machines chimes 3 times. A few seconds between each.

To reset the logic board, turn off the machine, fold open the case and look for a small black button about 1/8" in diameter within a silver square hosing about 1/4" square. On the B/W I think it's near the DIMM slots IIRC. Push this once and then restart. You'll have to reset the clock afterward.

I aslo looked at your link to the firewire card and don't see any mention of OHCI compliance. You might want to consider trying another card if the above doesn't work.

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post #293 of 2181 Old 04-12-2004, 05:59 PM
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Thanks cliff... I will get another firewire card and try it out just in case.
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post #294 of 2181 Old 04-12-2004, 06:55 PM
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I went into service mode tonight after letting the TV warm up for an hour. Headed over to INHD since that was the station that I tested with yesterday. There was very little overscan in service mode. Minor adjustments got it perfect. I even took another screenshot from my Mac and compared to the output on the TV. No difference. The issue yesterday either had something to do with the transmission of the baseball game to INHD or possibly there is a big difference between 720p and 1080i. I'll have to look at that when there's another game on. Would be interesting to see if there is a difference between a basketball game and a baseball game...

Quote:


Originally posted by EatingPie
I want to add that you will never be able to completely eliminate overscan. The edges start to bow and warp at a certain point. And it's not necessarily desirable anyway since most things get filmed with overscan taken into account... and the overscan allows a 1.85:1 image to fill your screen without black bars.

Your target would be between 5% to 10% overscan. I'd call 5% very low, and 10% a bit high. You can do this yourself if you can get into the service menus, and have a disk that shows geometry patterns on your screen (Avia / Video Essentials).

-Pie


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post #295 of 2181 Old 04-12-2004, 07:15 PM - Thread Starter
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Originally posted by Cooknn
I went into service mode tonight after letting the TV warm up for an hour. Headed over to INHD since that was the station that I tested with yesterday. There was very little overscan in service mode. Minor adjustments got it perfect. I even took another screenshot from my Mac and compared to the output on the TV. No difference. The issue yesterday either had something to do with the transmission of the baseball game to INHD or possibly there is a big difference between 720p and 1080i. I'll have to look at that when there's another game on. Would be interesting to see if there is a difference between a basketball game and a baseball game...

Yea, that's it, it must have been the baseball Did anyone check the pitcher?

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post #296 of 2181 Old 04-12-2004, 07:45 PM
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Hello,

Here is a zip file for a very simple interface for the Motorola 6200 only.

http://mac_hdtv_timer.home.comcast.n...meShifterX.zip repaired link

It has the various record and stop scripts controlled by buttons. All the scripts still need to be saved to the script library as before to support iCal integration. Hopefully, a better interface will surface.


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post #297 of 2181 Old 04-12-2004, 07:57 PM
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Originally posted by rcliff
Yea, that's it, it must have been the baseball Did anyone check the pitcher?

Haha! I was referring to the broadcast

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post #298 of 2181 Old 04-12-2004, 09:10 PM
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Originally posted by Cooknn
I went into service mode tonight after letting the TV warm up for an hour. Headed over to INHD since that was the station that I tested with yesterday. There was very little overscan in service mode. Minor adjustments got it perfect. I even took another screenshot from my Mac and compared to the output on the TV. No difference. The issue yesterday either had something to do with the transmission of the baseball game to INHD or possibly there is a big difference between 720p and 1080i. I'll have to look at that when there's another game on. Would be interesting to see if there is a difference between a basketball game and a baseball game...

D'oh, didn't realize it was a 720p on a 1080i TV! That's a non-integral conversion, so the algorithm probably uses some fudge to get a better image. That's probably the issue. See if you can compare a 1080i image, like the Tonight Show or HBO... those both go out at 1080i.

But it sounds like you're good from your check in the service menus, and that's the most important.

-Pie

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post #299 of 2181 Old 04-12-2004, 09:15 PM
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Quote:


Originally posted by FriarWyer
The timecode generation in VirtualDVHS is somewhat of a hack. The calculation of the current timecode is based on the position in the file, and the current instanteous bit-rate. For streams that have a highly variable bit-rate, it is not very accurate, especially the farther you go into the file.

Any other suggestions for a better algorithm? For sequential playback, I could just count frames (pass the stream through a demuxer and look for mpeg pichdrs), but I wanted a scheme that can handle time-code calculations in a random access method as well.

Didn't see your post, and went into the source myself... was going to post the exact same question!! I actually slapped my head when I realized the algorithm used the (HIGHLY) variable bitrate as a constant in the calculation!

I hacked the MPEGtransmitter class to allow access to the currentMPEGTime field, but this didn't work either... though I know just about nothing about MPEG streams and have no real idea what this variable holds.

Is there a time embedded in the packet? Is there a good overview of the .ts packet format? And lastly... Friar are you the guy who created the customized VirtualDVHS app?

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post #300 of 2181 Old 04-12-2004, 10:47 PM
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Didn't see your post, and went into the source myself... was going to post the exact same question!! I actually slapped my head when I realized the algorithm used the (HIGHLY) variable bitrate as a constant in the calculation!

I hacked the MPEGtransmitter class to allow access to the currentMPEGTime field, but this didn't work either... though I know just about nothing about MPEG streams and have no real idea what this variable holds.

Is there a time embedded in the packet? Is there a good overview of the .ts packet format? And lastly... Friar are you the guy who created the customized VirtualDVHS app?


Regarding the currentMPEGTime variable in the MPE2Transmitter, it doesn't have any relationship to the concept of file relative time-code. It's used by the transmitter's stream-bit-rate follower code to determine when to send ts packets over FireWire (and when not to), as well as for generating the soure-packet-header that's prepended to every ts packet in the FireWire stream.

Regarding a good overview of the ts packet format, it's called IEC 13818-1.

Regarding time-code embedded in the stream, even if there is a time-code in the packets (which there can be at the mpeg video es level), I wouldn't use it, because it has no bearing on the time-code relative to the file position, which is the useful parameter for a program like this.

I think a good solution is to create a secondary file during the recording of a stream, to save frame start locations, such as filename.nav, or filename.pos, to go along with the stream file, filename.m2t.

As ts packets are saved to the .m2t file, feed them to a ts reader/demuxer, that can detect frame starts. Record some information such as frame-start ts packet position in the stream (in bytes (save 64bits per frame), or in ts packets ( save 32bits per frame). Possibly, save picture type (I,P,B), and some other info for each frame that could help in trick modes playback as well.

For playback, try to open both the stream file, and the navigation file (if it exists). If the navigation file doesn't exist, revert to today's sloppy time-code method, But, if the navigation file does exist it then becomes a way to determine exact time-code based on current playback position, as well as it allows for random navigation within the file.

This feature should be enabled/disabled through a button on the preference pane, so that people running on slower systems, (you know who you are), wouldn't incur the extra CPU overhead required to pull this scheme off.

And lastly.. No, I'm not the guy who created the customized VirtualDVHS app.
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