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Old 01-09-2013, 06:23 PM   #1
ElJimador
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Video ReDo questions from a newbie

Hi folks. I just bought a Premiere to make the jump over from Comcast's DVR service and the biggest reason I wanted to do so was the ability to save my recorded HD programs to my PC, edit out the commercials, then play them back through my DLNA blu ray player and on occassion burn some to DVD. I'm looking for the most user friendly software to do this and from what I've read on this forum and others it sounds like Video ReDo is probably the best option for me (I haven't ruled out kmttg but from the screen shots I've seen it looks a bit dense for someone just starting in this area, and if anyone has other suggestions I'm certainly still open to those as well).

Anyway, assuming I go with VDR, I'm trying to understand the difference between different output formats and therefore which version of VDR is probably best suited for me. Because as much as I've been tooling around on this subject lately, I don't really understand the difference between, say, MPEG-2 and MP4. If I can play both back through my BD player then is there a difference in the available resolutions and quality between them? My goal is to save the files in as close to HD broadcast quality as possible and I don't really care that much about disk space since I have plenty of room on my NAS for them. So what should I be looking at exactly to decide what kind of files I should save these as and whether it would be a good idea to pay a little more for the VDR TVSuite H.264 or whether I could get the same thing for my purposes for less with the VDR Plus?

I know there are free trials of VDR available and I expect to start doing plenty of experimenting on my own within the next week or so. Just thought I'd throw the question out here first in case anyone who's already been down this road might want to share from their experience. Thanks.

BTW, my first post here but really appreciate this forum. It's been a great resource in helping me make the decision to move over to Tivo.
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Old 01-09-2013, 08:11 PM   #2
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KMTTG is only used to transfer shows to/from the Tivos. There are no formats to choose from before downloading. When you download from a Tivo, it will be a .TiVo file, which is encoded with your Media Access Key. If your system has/had Tivo Desktop installed, you can play the .Tivo files on your computer, otherwise it needs to be decoded, which then it will be a .mpg file. KMTTG will not make DVDs.

You would need to use VideoReDo TVSuite to edit any commercials or any content to remove or add something. VideoReDo TVSuite will make DVDs. VideoReDo Plus is similar except for the DVD authoring feature. Using free trial, you would only be able to burn a small portion and not the entire video to DVD. (VRD is only for Windows, No MAC version)
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Old 01-09-2013, 08:59 PM   #3
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The main difference between Mpeg2 and H.264 (mp4) is file size.
The Tivo records in Mpeg2. If your blu ray player can play .mpg files and you have no space problems, VRD TV Suite version 3 would work for you.
The only "conversion" taking place is the removal of the .tivo encryption which happens very fast.
If you were to convert a .tivo file to any format other than .mpg, that would take more time and computer processing power.

Can you burn DVDs from your DLNA blu ray player? If so, VRD Plus (cheapest version) might suit your needs.
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Old 01-09-2013, 09:46 PM   #4
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I think a couple of wrong impressions were given in earlier posts. First VRD can be trialed uncrippled for 15 days. For this you need to perform the free-trial registration found in its menu system. Second I don't think the OP is interested in making DVD's, so unless he wants to have H.264 outputs he needs only the least expensive ("plus") version of VRD. Third, kmttg does a lot more than just transfer and decode .Tivo files to .mpg. It will also run VRD and Comskip, and I believe it will make h.264 encodings using either Handbrake or x.264. Not sure about the details because I don't use kmttg. All this is free except when it runs VRD. VAP (link in signature) does similar things but it doesn't transfer files from the tivo.
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Old 01-10-2013, 01:43 AM   #5
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I was looking for an easy program to unwrap the .tivo file, edit the file and then beable to transfer it back to my TivoHD from the Now Playing List in the edited form. VideoRedo does all of that for me.
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Old 01-10-2013, 01:59 AM   #6
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FYI the newest beta has a new output profile for TiVo-TS which can save a .tivo file to an H.264 .tivo file which can then be pulled back to a TiVo using standard TiVo Desktop software. Only works with Premiere units though since they are the only ones that support the TiVo-TS format.

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Old 01-10-2013, 09:27 AM   #7
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Originally Posted by steve614 View Post
The main difference between Mpeg2 and H.264 (mp4) is file size.
The Tivo records in Mpeg2. If your blu ray player can play .mpg files and you have no space problems, VRD TV Suite version 3 would work for you.
The only "conversion" taking place is the removal of the .tivo encryption which happens very fast.
If you were to convert a .tivo file to any format other than .mpg, that would take more time and computer processing power.

Can you burn DVDs from your DLNA blu ray player? If so, VRD Plus (cheapest version) might suit your needs.
Thanks Steve, and to the others who've responded so far. Really appreciate the feedback. I can't burn DVDs from my player and although I don't expect to burn many since I'll be able to watch them all through DLNA, the more I think about it I would prefer to have that in the software too to make it easier when I do want to. So that rules out VRD Plus I guess. And though I said disk space isn't a concern to me, when I think about accumulating these files over time it does seem like it's probably well worth the $20 difference between the v3 and H.264 versions of TVSuite to get the H.264. (I've read a bit more since my original post and I hadn't realized that H.264 was that much more efficient in terms of the file sizes).

BTW, the owner's manual of my blu ray player (LG BD690) says that for video files the extensions it will play through either DLNA or disc/usb include .mpg, .mpeg, .mkv, and .mp4 (among a few others like .wmv, .avi, .divx, etc) with codec formats MPEG1 SS, MPEG2 PS, MPEG2 TS, and H.264/MPEG-4 AVC and audio formats Dolby Digital, DTS, MP3, AAC, and AC3. Since some of that is still Greek to me (codecs particularly), I'll just ask: any difficulty that anyone sees w/playback there with either version of TVSuite? I note for example that it doesn't include .ts as a supported file extension (although on the AVS forum thread for my player I've seen others say that it will play even though the manual doesn't say so).

I guess that's my only big trepidation out of all this (and what free trials are for), is that there's some detail I'm missing now that's going to make the DLNA playback not work or a lot more difficult to achieve then I'm currently imagining. Because really when it gets down to it, I really just want something that will take off the .tivo wrapper, let me edit out the commercials without too much trouble, and then let me save a single file for DLNA playback through my BD player (and the more I think about it, that I can easily rip to finished DVD that will play in anyone else's player too). If I can get that to work right without a bunch of additional steps then I'll see if I want to get into anything more advanced from there.
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Old 01-10-2013, 09:46 AM   #8
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FYI the newest beta has a new output profile for TiVo-TS which can save a .tivo file to an H.264 .tivo file which can then be pulled back to a TiVo using standard TiVo Desktop software. Only works with Premiere units though since they are the only ones that support the TiVo-TS format.

Dan
Thanks Dan. If I do go with the H.264 version I'll probably experiment w/this and see how playback through my Premiere compares to DLNA playback. I'd just rather not save both .tivo and non-.tivo versions of my recordings when my goal was not to be reliant on any one device and have recordings I could still play through DLNA if my Tivo turns into a brick or I decide to give it up down the road. However if I see advantages to playback through the Premiere (better UI or whatever) then I suppose your software probably makes it easy enough to just save my finished recordings as .tivo files and if then if I decide to later, convert them all over for DLNA playback instead?

Really looking forward to trying VRD.

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Old 01-10-2013, 02:08 PM   #9
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The TS files generated by the newest beta are also Premiere compatible. However TiVo Desktop doesn't work with them so you need a newish build of pyTiVo to be able to pull those over without transcoding.

Although basically all a .tivo file is is a PS or TS file with a special header. Most programs will ignore the head and skip to the actual audio and video data. Once the file is processed by VRD it's decrypted so as long as your playback device can skip the header it should be able to play them just fine. And if you ever run unto a device that can't skip the header it's trivial to remove it and end up with a standard .mpg or .ts file.

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Old 01-19-2013, 10:14 PM   #10
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Here's my blog post on how I did exactly this: http://benmoore.blogspot.com/2012/12...ury-video.html

It seems too easy. Maybe I've just been lucky so far.
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Old 01-29-2013, 05:46 PM   #11
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Just to update, it's been about 10 days now playing w/the TV Suite H264 version of VRD in trial and I'm really happy with it. I didn't realize though how long it takes to re-encode a program (especially a movie or a football game) to H264. Given that along w/some of the other free tools I've since found for video file conversion and DVD/BD authoring (Handbrake, AVCHDCoder, ImgBurn) my current lean is to go with the basic VRD Plus version to save my recorded programs as MPEG2 .TS (which I've found I can play back through my blu ray player) and then if I decide later I want to convert them to H264 or burn them to disc I'll have other tools to do that. The only tradeoff is that I'll definitely need to upgrade my 1TB NAS sooner but that seems worth it to save myself the re-encoding time plus the quality of keeping everything in its native format.

Question, BTW: am I correct in that assumption that saving the files in the same MPEG-2 .TS format they're broadcast should preserve the best quality? I've tried watching the same show saved as .TS and H264 and so far I haven't been able to see much difference but I haven't really had time to compare them too closely either.
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Old 01-29-2013, 06:21 PM   #12
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Question, BTW: am I correct in that assumption that saving the files in the same MPEG-2 .TS format they're broadcast should preserve the best quality?
Yes. TV is broadcast in the MPEG-2 format. Since the Tivo records the signal "as is" the resulting file is as pure as you're going to get, and VideoReDo will preserve that.

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I've tried watching the same show saved as .TS and H264 and so far I haven't been able to see much difference but I haven't really had time to compare them too closely either.
I think you would be hard pressed to tell the difference.
The H264 format retains HD quality while reducing file size. It takes a lot of computer processing power and that's why it takes so long to recode.
If you have other software programs that convert video to H264 faster than VRD, I would question the quality of the output file.
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Old 01-29-2013, 07:51 PM   #13
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Thanks Steve. So far the only other tool I've used to convert to H264 is Handbrake which seems to take just as long (and using AVCHDCoder to author an ISO to burn to disk takes even longer). Which I guess really shouldn't be that much of a concern since I can just let these programs run overnight or when I'm at work. I'm just thinking why bother with it to reduce the file size when storage isn't that expensive now and only seems to be getting cheaper? When I first posted here I hadn't really done anything with video files yet and I thought that converting to H264 would actually increase the quality at the same time it reduced the file size. Now that I'm learning a little more I think my preference is going to be to save all files in their original format as long as I can play them back through my blu ray player (which for blu ray rips means converting .M2TS and VC-1 since my player won't play nice with those and basically saving everything else as MPEG2 .TS or H264 MKV).

Like I said though, I'm only about 10 days into all this fun stuff. So I'll probably be posting more questions and changing my mind plenty more times before I form any concrete opinions about anything. Anyway, thanks for the feedback. It really helps.
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Old 01-30-2013, 02:49 PM   #14
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Recoding video is one of the hardest things for a PC to do. So it's one of the few things left that scales directly with the speed of your computer. The faster your computer, and the more cores it has, the faster it will be able to convert video. In my case I have a quad core i7-2700K with hyper threading. I can convert MPEG-2 HD to H.264 in about 2/3 real time. Meaning it takes about 40 minutes to convert a 1 hour program. We have at least one customer on our forums with the top of the line 6 core Intel processor and he has reported getting about 1/2 real time.

If you scale the video down and lower the bitrate it will go faster. I can convert an hour long video to SD in about 15 minutes.

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Old 01-31-2013, 12:35 AM   #15
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Thanks Dan. I've got an i7 too (2670) so I figured it the processor was doing its job and the time the conversions to H264 were taking was just the time they're supposed to take and certainly not any reflection on your software. I just didn't realize what a workout it would be for more laptop. As laptops go it's a beast (17" HP Pavilion with dual SSD and SATA hard drives) but the other day I left VRD, Handbrake and AVCHDCoder all running jobs overnight and woke up to a BSOD talking about a memory dump due to faulty or mismatched memory and some other code referencing my Intel Graphics (which unfortunately is integrated so not easily upgraded if I wanted to). So I'm taking a few steps to upgrade (updating the Graphics firmware, upgrading from 6 to 16GB RAM, and getting a laptop cooler to hopefully keep the thing from overheating again) but if you have any other suggestions for tweaks that might help, let me know. Thanks.
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Old 01-31-2013, 12:46 AM   #16
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Thanks Steve. So far the only other tool I've used to convert to H264 is Handbrake which seems to take just as long (and using AVCHDCoder to author an ISO to burn to disk takes even longer).
Yes. There are a few things that can speed things up. One is to not translate the MOOV atom to the beginning of the file. This can cause some issues, but pyTivo, at least, uses QT-faststart, which can stream the MOOV atom at the outset on the fly. Another is to get a faster CPU with more cores.

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Which I guess really shouldn't be that much of a concern since I can just let these programs run overnight or when I'm at work.
I've sometimes left the conversions running on multiple PCs simultaneously for weeks.

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I'm just thinking why bother with it to reduce the file size when storage isn't that expensive now and only seems to be getting cheaper?
Two reasons:

1. Although drive space continues to fall in price, a 30% or more savings is still a 30% or more savings. Remember, too, it is not just purchase price, but also power,once one starts adding more and more spindles to a system. Certainly coding to h.264 has saved me at least $300 so far, significantly delaying necessary upgrades to both my RAID systems.

2. If you are sending video back to the TiVo, h.264 / MP4 transfers much faster than MPEG-II video, especially for 720p. This is even true for the Premiere (about a factor of 2), but the difference is large for an S3 and positively huge (a factor of better than 4) on a THD.

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When I first posted here I hadn't really done anything with video files yet and I thought that converting to H264 would actually increase the quality at the same time it reduced the file size.
No. Unless one does some sort of specific video editing, conversions can only make the PQ worse, albeit in some cases not noticeably so. What it does do is allow one to compress the video farther than one can with MPEG-II without a significant loss of PQ.
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Old 01-31-2013, 12:47 AM   #17
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You should never run multiple encodes at the same time. That actually produces results that are wose then running them one at a time because the computer has to try and allocate resources to all of em at once.

In VideoReDo you should ty the batch manager. Then you can queue up several encodes to run over night and it will actually encode them one at a time in sequence.

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Old 01-31-2013, 08:29 AM   #18
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Recoding video is one of the hardest things for a PC to do.
Indubitably.

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So it's one of the few things left that scales directly with the speed of your computer. The faster your computer, and the more cores it has, the faster it will be able to convert video. In my case I have a quad core i7-2700K with hyper threading. I can convert MPEG-2 HD to H.264 in about 2/3 real time. Meaning it takes about 40 minutes to convert a 1 hour program.
Yeah. This machine has an older, 2.8 GHz, six core Phenom II, and without shuttling the MOOV atom, it can recode 1080i MPEG-II files to h.264 / MP4 just a bit faster than real-time.

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We have at least one customer on our forums with the top of the line 6 core Intel processor and he has reported getting about 1/2 real time.
Yeah, one of my servers runs a 4.0 GHZ 8 core Vishera CPU with 8G of RAM. It just converted a 32 minute video in just under 20 minutes.

Last edited by lrhorer : 01-31-2013 at 08:35 AM.
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Old 01-31-2013, 08:34 AM   #19
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You should never run multiple encodes at the same time. That actually produces results that are wose then running them one at a time because the computer has to try and allocate resources to all of em at once.
There is absolutely nothing wrong with running one encode at a time on multiple computers. Please re-read what I wrote. "...running on multiple PCs simultaneously" != "...running multiple simultaneous conversions on a PC".

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In VideoReDo you should ty the batch manager. Then you can queue up several encodes to run over night and it will actually encode them one at a time in sequence.
How do you think I ran recode jobs for weeks on end?
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Old 02-01-2013, 01:03 AM   #20
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I was actually responding to ElJimador, your post just snuck in there while I was typing. He mentioned running jobs simultaneously in VRD, Handbrake and AVCHDCoder.

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Old 02-01-2013, 10:28 AM   #21
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Although drive space continues to fall in price, a 30% or more savings is still a 30% or more savings. Remember, too, it is not just purchase price, but also power,once one starts adding more and more spindles to a system. Certainly coding to h.264 has saved me at least $300 so far, significantly delaying necessary upgrades to both my RAID systems.
Excellent point. I started looking more seriously into a NAS upgrade since my last post and the more I'm getting into that the more I'm seeing the value of converting to H264, and I hadn't even considered the power consumption part of it. So yeah, I've changed my mind on that.

BTW, any NAS recommendations? I had originally just been thinking about getting a 3 or 4TB box like my current WD MyBookLive but as I'm starting to realize how quickly that might fill up even converting everything to H264 I'm thinking now about something more expandable like a 2 or 4 bay Synology. I'm just noticing that price jump when you look at anything over 3TB and I'd rather not get anything now that's not going to remain incorporated in my setup as I grow. (The 1TB NAS I have now I'll just keep reserved for pics and music).
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Old 02-01-2013, 10:34 AM   #22
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You should never run multiple encodes at the same time. That actually produces results that are wose then running them one at a time because the computer has to try and allocate resources to all of em at once.

In VideoReDo you should ty the batch manager. Then you can queue up several encodes to run over night and it will actually encode them one at a time in sequence.

Dan
Thanks Dan. I thought having a quad core processor meant that I should be able to run more than 1 encode at a time (again, not really appreciating how much work these jobs are for your CPU). I'll stick to that going forward and will try out the batch manager too. Appreciate the tip.
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Old 02-01-2013, 03:42 PM   #23
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Video encoders are multi-threaded, meaning they will use all 4 cores to do one encode and speed up the process. It's much faster to run theme one at a time.

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Old 02-21-2013, 08:13 PM   #24
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Hi,
I just wanted to chime in.
1st about a year ago I also grabbed the VideoReDo trial and played with it for a while. I decided it was an excellent product that was worth it's price and I bought the TV Suite version figuring that although my immediate plans didn't need H.264 encoding or processing, that I might eventually.

I am currently using it in conjunction with kmttg, which is very easy to set up and use (just follow the instructions on the site). kmttg is great for queuing up downloads and decodes from your tivo, and I just discovered that it can run the VideoReDo adscan and create a videoredo project file for your review. I mostly don't bother removing the commercials because even once the ad scan is done you have to review and adjust all cuts and that can be a little time consuming.

While I'm posting, maybe I can ask those people if there is a kmttg profile that they find maintains the best quality and can be sent back to the tivo by pyTivo? I've got VideoReDo and I know that kmttg has ffmpeg and handbrake profiles as well. I'd like to save some space, but keep the quality as close to the original mpg2 as I can.

Also does the container format matter? I hadn't thought so, but I recently saw a comment by Dan203 where he said that mkv loses some timing and that mp4 was better if you were ever going to re-edit the video. I haven't found any other confirmation of this by googling, but Dan203 is a developer of VideoReDo so I'm looking for more information.
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Old 02-22-2013, 05:15 PM   #25
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It's not specifically the MKV format that's the problem. The MKV format actually supports higher resolution time stamps. But for some reason everyone has standardized on using millisecond resolution time stamps for MKV. For playback that's fine, but for frame accurate editing it's a problem because the math doesn't quite work out and you can end up with some rounding errors that cause a shift of +/- one frame. (it also causes issues with our syncing routines)

If you remux the file using MKVMerge and use the CLI option to set the time stamp resolution higher, say to 10,000 ticks per second, then it should work just as well as any other format. However 99% of the MKVs you download, or even the ones output by VideoReDo, will use the millisecond resolution which can potentially cause a problem.

All other formats will typically use a time stamp resolution of 90KHz or higher, which is why they work fine. Although I have seen a few MP4s with lower resolutions that cause a similar issue in VRD. However they're rare and all MP4s output by VRD use 90KHz ticks so they will work fine. Originally I tried outputting MKVs with higher resolution ticks too, but we got complaints because apparently some players just assume MKVs will use milliseconds and don't actually adhere to the set value. So for compatibility we dropped back to ms and just try to warn people of the issues.
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Old 02-22-2013, 11:34 PM   #26
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It's not specifically the MKV format that's the problem.
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All other formats will typically use a time stamp resolution of 90KHz or higher, which is why they work fine. Although I have seen a few MP4s with lower resolutions that cause a similar issue in VRD. However they're rare and all MP4s output by VRD use 90KHz ticks so they will work fine. Originally I tried outputting MKVs with higher resolution ticks too, but we got complaints because apparently some players just assume MKVs will use milliseconds and don't actually adhere to the set value. So for compatibility we dropped back to ms and just try to warn people of the issues.
Dan, thanks for the response, it was very clear and helpful. Just to make sure I really understood, the millisecond resolution is the same as 1KHz ticks, or equivalently 90KHz is the same as 1/90 millisecond resolution.

I've still got so much to learn about this stuff, starting with what exactly the container format provides. I'm guessing the timestamps are used to sync the various parts that are in the container (most notably the video with the audio?) and those parts don't carry their own timestamps?

I would have thought that the video and audio had inherent timing as long as they are based on the same start point they have a built in rate that would keep them in sync and intermediate sync points could always be calculated by starting from the beginning.
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Old 02-24-2013, 01:12 AM   #27
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Yes. Milliseconds are 1KHz or 1000 per second and 90KHz is 90000 per second. The reason ms isn't enough is because most video frame rates don't divide evenly into 1000. For example NTSC is 29.97fps. 1000/29.97 = 33.3667. That get's truncated to 33 and causes a rounding error.

The timestamps have a few uses. First off they tell the play clock when to display or play a frame. So no matter how fast the computer is able to demux and decode the frames it plays them at the proper time. This maintains both smooth playback and audio/video sync. In this case ms is OK because if the frame is displayed +/- 1/2 a ms it would never be noticed by the user.

However in VideoReDo we also use them for maintaining sync during output, even after some frames have been cut, and for doing the seeking to the start/end of cut points. If the time stamps are inaccurate then it can cause errors in both those portions of the code.

I'm working on trying to come up with a conversion routine that will properly convert ms to 90KHz without the error. However it's not as simple as it sounds. To maintain proper sync and playback speed the ms timestamps in MKV jump. So for example with 29.97 the frames will be...

33, 66, 100, ...

With every 3rd frame jumping an extra ms like that it makes it difficult to compensate for. especially considering every frame rate will have a different pattern and two files with the same frame rate might as well.
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Old 02-24-2013, 09:22 AM   #28
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Thanks Dan, that was a great explanation!

And I think I understand the VideoReDo problem when writing after frame edits have been made.

So most tools that remux an mkv into an mp4 don't normally change the timestamp resolution from 1KHz to 90KHz?

Hmm, normally NTSC at 90KHz (90000/29.97=3003.0030) the frames would be at:
0, 3003, 6006, 9009...
and you only jump an extra tick every 333 frames instead of every 3 frames.

Doing a straight conversion of the ms timestamps to 90KHz would give you:
0, 2970, 5940, 9000...

However, what if you converted a ms timestamp to a frame offset and that frame offset back to 90KHz? So for NTSC video:
66ms * (29.97 frames/s) = 1.978 frames, rounded to the nearest frame is 2.

A frame offset of 2 at 90KHz is at tick 6006, which is what it would be if the timestamp was originally 90Hz instead of having the 66 tick difference.

I think that this may occasionally be off a frame as you explained, however I think it avoids any cumulative errors.

Dan, I hope the above wasn't presumptuous but maybe it could help your algorithm. I know I don't know the intricacies of the problem (everything I do know, you've just explained to me!).

Mike
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Old 02-25-2013, 09:31 PM   #29
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This thread has been very helpful

I am newbie about to enter this arena also and am considering similar options too. This thread has been very helpful. Thanks to all.

One of the difficulties I am encountering reading this and so many threads on these related topics, is terminology. Could someone kindly thumbnail some of the terms being used: encoding, decoding, transcoding, codecs, decrypt (haven't seen encrypt, does it apply?)

For context, my needs are just to occasionally make a DVD playable on a PC or a player or occasionally make a snippet to upload to my Android (HTC Rezound) or Youtube to share with a friend. I guess editing out ads would be nice, but not critical. Because I don't have much volume in mind, MPEG2 will probably be fine.

I got faked out recently when a DVD I burned from my Tivo (Humax S2 with burner), would play on my PC (w/WMP), but not my friend's PC or player. I think I have just figured out from reading all these threads it is because my PC has Tivo Desktop with my MAK.

Thanks to this learning curve, I now realize that several Tivo DVD's I've burned over the years will be useless if my Tivo becomes a brick. I never realized that until now. I may have more converting to do than I thought.

Last edited by hershey4 : 02-25-2013 at 09:33 PM. Reason: left out target device smartphone
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Old 02-25-2013, 09:56 PM   #30
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Quote:
Originally Posted by hershey4 View Post
I am newbie about to enter this arena also and am considering similar options too. This thread has been very helpful. Thanks to all.

One of the difficulties I am encountering reading this and so many threads on these related topics, is terminology. Could someone kindly thumbnail some of the terms being used: encoding, decoding, transcoding, codecs, decrypt (haven't seen encrypt, does it apply?)

For context, my needs are just to occasionally make a DVD playable on a PC or a player or occasionally make a snippet to upload to my Android (HTC Rezound) or Youtube to share with a friend. I guess editing out ads would be nice, but not critical. Because I don't have much volume in mind, MPEG2 will probably be fine.

I got faked out recently when a DVD I burned from my Tivo (Humax S2 with burner), would play on my PC (w/WMP), but not my friend's PC or player. I think I have just figured out from reading all these threads it is because my PC has Tivo Desktop with my MAK.

Thanks to this learning curve, I now realize that several Tivo DVD's I've burned over the years will be useless if my Tivo becomes a brick. I never realized that until now. I may have more converting to do than I thought.
Decrypt = Removing the protection imposed by the Tivo and then it will be a regular mpeg2 file.
Encode = convert to another format to be used on a different device, ie: ipad, iphone, etc.

There is no 'decode' in a Tivo sense.

Transcode = the process the Tivo does to convert the video files to a proper format so it plays on the Tivo.

You can take the files off the Tivo DVDs, if it has .TiVo file extension, remove the protection with programs such as TivoDecode and there would be .MPGs instead. You would not need the Tivo involved.
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