be-at.tv changed their internal urls - how to download?

[blimey]

Maybe I just can't hear the few ms of audio gaps.

Below is a link to a small snippet (the first 6 min, or 30 .beat files) of time-warp-2013/chris-liebing (Session 002646/Recording 001460) that was concatenated with ffmpeg. Please tell me if you detect any audio gaps;

001460_FHF.mp4

(uncheck the box before "Use our download manager and get recommended downloads" in order to get the file without the garbage install wrapper)

But you're right that it is unlikely that the downloader or download method has any effect, so long as the downloaded .beat files were able to be converted with BeatConvert.php.

[sebastian]

@blimey: No gaps at your file. And no gaps if I'm converting the same session too at home.

So it's a session based problem. :-)

Here's the one that always does gaps between each file:
hxxp://www.be-at.tv/brands/jaarbeurs-utrecht/timewarp-2012/marcel-fengler

Maybe KSV could have a look at it? :-)

[blimey]

Originally Posted by sebastian

So it's a session based problem. :-)

Here's the one that always does gaps between each file:
hxxp://www.be-at.tv/brands/jaarbeurs-utrecht/timewarp-2012/marcel-fengler

Does that one play without any gaps whatsoever when playing it on the website in their flash player? How common are these "gapped" sessions?

It is possible that the beat people just did some bad encodes, or made some other sort of mistake. Unless it is very common, or if the "gapped" sessions play entirely gap-free on the website.

[sebastian]

It plays entire gap-free on their website.
Didn't try many other sessions yet though.

[blimey]

Originally Posted by sebastian

Here's the one that always does gaps between each file:
hxxp://www.be-at.tv/brands/jaarbeurs-utrecht/timewarp-2012/marcel-fengler

I did the first 30 .beat files of timewarp-2012/marcel-fengler (Recording 001196) with ffmpeg and it seems ok to me. I'd have to do the whole thing to be 100% sure of sync, but it seems right so far. Check it -- if it is "gapped", point out where;

001196_FHF.mp4

(uncheck the box before "Use our download manager and get recommended downloads" in order to get the file without the garbage install wrapper)

[sebastian]

Very strange. Your recording is ok, no problems.
What version of ffmpeg are you using? I tried several static builds from http://ffmpeg.zeranoe.com/builds/

[blimey]

Actually, there is a sync problem. I'm looking into it now and will report back later.

If you follow the music in the web player, or in the individual converted beat file, you can see that the music is in a different place compared to my joined file just before they go to the guy at the panel for the very first time around 2:20-2:30.

Checking it further now.

[sebastian]

Any news? I also wonder why ffmpeg behaves differently at you and me while joining the files.

[blimey]

Yes, I was able to get that session (timewarp-2012/marcel-fengler, recording 001196) in sync.

This session has 463 beat files (0000-0462). After processing them all with the BeatConvert.php script, you may notice that if you play any one individual flv file, the ending time of each individual file tracks along respective to the whole session time.

For example 0462.flv has an ending time of 132:27 (the end time of the whole session).
0461.flv has an ending time of 132:24 (where it ends relative to the whole).
And so on, for all the earlier files.

The flv containers for all of these pieces are encoded in such a way that the collection "appears" as one big individually encoded flv file to the flash player. This is due to the way they split up the original flv file. I'll spare the details about that.

Anyway, you can simply reconstruct the original flv file from all the pieces using simple binary file operations.

To put it as simply as possible, you leave 0000.flv as-is, then cut the first 32 bytes from each of the remaining files (0001.flv through 0462.flv), and then join them all together (in order) and you have the original flv in one file.

When I say join them, I mean in terms of binary file operations, not video operations.

I used "replace pioneer 2.73" to quickly do these binary file operations in a GUI, but a script could easily be constructed.

Once you have the original flv file in one piece, you can copy it to another container like mkv using ffmpeg (the best way).

Flvextract won't work on the original flv because of some anomalies in the 264 bitstream they used. And if using mp4box, some special commands are needed for the same reason. But if you just stream copy the original flv to mp4 or mkv container using ffmpeg it will work straight away. Or you can just leave the original flv alone if you can use it that way.

[sebastian]

Thank you so much for your investigation on this problem.
I'll try it this weekend and keep you posted. :-)

If anyone also knows a command line based app to strip the bytes, please let me know, so I could do the whole process via a batch file. :-)