Reliable transfer of .TS files?

pyTiVo?

 

Sorry, I mis-read your question. After realizing you want to pull the .ts file from TiVo, I tried transferring a .ts file from my Premiere XL4 to a Windows PC using a lesser-known program called TiVoPlayList.

http://www.tvreviewer.com/tivoplaylist/

After scanning through the video to check for any problems, the show seemed to look and sound fine. But I also downloaded the same file using kmttg and found the size and quality to be identical. I'm not a hardcore videophile so maybe I'm just not seeing the dropped video frames you described. Are they obvious and constant or subtle and random?

 

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All of the available transfer utilities receive the same data from a TiVo when transferring, in either .PS or .TS format. If you're not getting everything(ie dropped frames), it's happening further up the pipeline than the transfer utility(inside the TiVo during the re-muxing process, or from the cable company). They just open an http connection and accept whatever data TiVo sends.

If there are very small glitches in the video signal coming from your cable co, I *believe* the ps format may be innately more tolerant of these issues than ts. Someone with more knowledge of video coding would have to confirm and/or expand on that though, it's beyond my ability of expertise.

 

It does, but, it won't give different results.

Apart from the difference between PS and TS transfers, there should be no other differences.

 

I think the main reason why is because the TS files require less processing by the Tivo box since it's basically sending the original broadcast to the PC while the PS files are often remuxed by the Tivo and thus any errors in the stream are fixed or taken care of. TS streams basically have all the error correction bits and are thus more robust when being sent to a unit while PS streams don't have all the error correction bits and are not used for OTA or QAM broadcasts as a result. What's nice with using the TS option is that your recording is much less likely to cut off in the middle or anywhere in the stream when it's transferring to your PC which leaves you with an incomplete recording. Whereas the PS stream will sometimes do that. I often find certain times when it's more likely to affect the majority of all recordings I've done to when it only happens once every two months. Usually in the summer is when I've noticed it to happen much more frequently while in other parts of the year it rarely occurs. But with those recordings that don't fully transfer over PS, they will transfer completely with TS, and I don't recall the last time a situation where the TS stream wouldn't completely transfer. However, with the TS stream I sometimes find that in parts of a recording there may be glitches in the stream that aren't present at all in the PS stream, and these glitches occur at the exact same location if I try to transfer the recording again. But I have found that sometimes say if I used Tivo Desktop to transfer a recording in TS format and I transfer the same recording in kmttg in TS format then the glitch won't be there at all. Then there's times when no program seems to make a difference. So best practice is to use PS format when transferring recordings even if it's slower you will not run the chance of having glitches in your recordings that weren't present in the original recording. However, if a recording cannot transfer completely then use the TS format and try kmttg, Tivo Desktop, and Tivo Web Server(even though kmttg uses this method too) and see if there is a difference with each case.

In terms of finding a more reliable method of transferring TS files, I have found that wired or wireless doesn't really make a difference since TCP would handle any errors made across the network. But as I stated above some programs may transfer the recording better than others but it's not always the case.

 

Which Tivo model are you using by the way just out of curiosity.

 

What tool you use to download doesn't produce different results. Tivo does all the work. No different then saying who pushes the button to turn on a TV makes a difference.

The difference is what took you use to decrypt. Tivo desktop uses the direct show filter. KMTTG has an option to use direct show filter, or use videoredo to decrypt which is about the same. BT default KMTTG uses tivolibre.

A fair comparison requires using the same decryption tool

 

Add my Roamio base model to the list. Try downloading the same recording from the TiVo a few times and you'll most likely get glitches in different parts of each download.

Here's a post I have on the suject at the VideoRedo support forum http://www.videoredo.net/msgBoard/showthread.php?35729-5-1-2-740-QSF-H-264-TS-logs-42-frames-removed-output-is-4-381-frames-2-26-shorter&p=122413#post122413

 

Do you notice the some of the glitches occur at the same locations in the downloaded file or does that never happen since for me it always seems to be the same glitches.

 

Are we comparing apples to apples? Are your recordings broadcast H.264 video w/AC3 audio? Are you downloading them in TS format? What are you using to download them?
Any glitch in the original recording may either transfer or prevent transfer.
A TS stream has to be intact in order to encapsulate the payload.
Glitch free recordings on the TiVo sometimes come over via TS ttg with their own TiVo made glitches (loss of sync and/or continuity in the ts stream delivered). I have one example recording left on my TiVo that I had to download 11 times to get a perfect transfer. In addition to discontinuities in the TS stream it would lose TS sync in one or more of 5 well defined areas of the TS stream. The last (11th) ttg TS download was sans glitches.
This has been my experience with my Roamio base unit and YMMV.

P.S. TiVo's official response is that TiVo Desktop is no longer available or supported. Doesn't work on the new Bolt, so it's antiquated tech that's been replaced by the new technology we all asked for called streaming! (You voted for it)

 

Are you determining whether there are any glitches using VideoRedo's QuickStream fix to see if there were any frames removed or are you using another possibly faster method? Also what setup on the tivo side do you use that you found ultimately reduces the glitches the most(i.e. not having any of the channels tuned to a working channels, having device on standby)?

I've read that Tivo Desktop does still work with the Bolt but that they don't officially support it so good luck talking to CSR about it (which usually doesn't make a difference anyway)

 

Loading the unencrypted TiVo files in a hex editor and examining the transport stream looking for loss of sync. Easiest after setting the hex editor line length to a ts packet size of 188 bytes.

Haven't determined anything reliable, I just keep downloading a program until I get a clean transport stream with no sync loss.

 

I know on your VideoRedo posts that you said you tried so many different things that you don't really know what resulted in the Tivo file transferring without any glitches, but have you tried transferring the same recording multiple times with the same configuration and it produces different results(i.e. one the recording transfers glitch-free while another time it doesn't)?

 

That's my next experiment. I have a one hour H.264 recording scheduled tonight. I'm going to download it a couple minutes after it's done recording, then wait until morning and download it again, then again tomorrow afternoon, etc. without messing with anything like delete/recover, standby, changing all channels, etc. I find if you look at the std (console) output of tivolibre using the -d debug flag it will tell you where it finds/recovers the TS packet sync loss which makes it easier to go to that location in a hex editor while examining the encrypted TiVo file you downloaded. If the TS sync loss in the encrypted TiVo files occur in different locations in different downloads of the same program from the TiVo, that pretty much points to the TiVo doing it as far as I'm concerned.