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skdvr
09-02-2010, 08:46 AM
OK, this may be a bit long winded but I am going to try to explain fully what I have happening here...

Last week I had a 4 day shoot at a local college. The first days program was 2 hours and 20 min, the other three days where right around an hour long. Three camera shoot recorded to MPEG 2 Studio Profile with the Tricaster Broadcast.

Get back to the Studio on monday and transfer all the files from the HDD of the TCB to an external HDD. I notice that the first shoot that is 2 hours and 20 min long is 53GB, and each of the hour long files are between 7.5 and 8GB. So that struck me as odd that it was SO much larger than the other files even though it is just over double the time. I transfer all the files and hook it up to my PC to drop them into Premiere to edit them down before burning a DVD. While the files are transferring to my PC, I click on the Edit Tab on the TCB and drop the first file into the timeline. It shows the clip as being 4 hours and 59 min long. About half way through the clip there will be 1 frame of video and then a few frames of black, then 1 frame of video and a few more frames of black. It continues this way until the end of the clip. Here is a link to a short clip of it on youtube. (http://www.youtube.com/watch?v=zqN-keUeNrA).

So I go to my PC with Premiere and import all 4 files... The three 1 hour segments work just fine. I can scrub through them, play them, what ever, no problems. The first clip (That TCB showed with the black clips) goes into the timeline no prob in Premiere and shows the correct length, but if I try to scrub through the clip or play the clip it locks Premiere up and I have to close it (or wait 10 min or so). So I thought that some how the clip on the TCB got corrupted, so I changed the name of the clip on the external HDD and hooked it up to the TCB and imported the clip into the timeline in the edit mode and it again showed the clip as being 5 hours long. I took the external HDD over to another PC that has Speed Edit and it too showed the clip as being 5 hours long.

Since I could not really edit the clip in Premiere I exported an Uncompressed AVI from premiere just to see what happened and that file works just fine. So at least I now have something that I can edit down (I had a problem with my backup too).

I tried to export a AVI file from the TCB just to see what happened and it did still show the black clips.

I talked to Tec Support yesterday and they told me that they have not seen this before and have no ideas, so I thought I would throw it out to you guys and see if any one has any thoughts. This is actually the second time it has happened to me, I have now lost confidence in my TCB's recording ability. I really do not like the standard MPEG 2 recording mode, it just looks like junk when going to DVD, at least since the Studio Profile is 4:2:2 it converts well to 4:1:1, BUT those black clips are a killer.

If there is anything that you would like me to try please ask away.

Phil

SBowie
09-02-2010, 08:48 AM
If there is anything that you would like me to try please ask away.Is there any chance at all that for the longer, problematic clip, someone simply forgot to turn Record off?

skdvr
09-02-2010, 09:05 AM
No... We where broadcasting this over the College CC TV and to an over flow room so we kept the feed live, but ended the recording when the kids started walking out.

Thanks for asking...

Phil

skdvr
09-02-2010, 09:43 AM
I analyzed two of the files. This first one is from the Bad Clip


General
Complete name : V:\Premiere\Wash U\Footage\Tricaster\8-26-10\8-26.mpg
Format : MPEG-PS
File size : 53.1 GiB
Duration : 2h 19mn
Overall bit rate : 54.6 Mbps

Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : [email protected]
Format settings, BVOP : No
Format settings, Matrix : Default
Format settings, GOP : N=1
Duration : 2h 19mn
Bit rate mode : Variable
Bit rate : 53.1 Mbps
Nominal bit rate : 25.0 Mbps
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:2
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 5.128
Stream size : 51.6 GiB (97%)

Audio
ID : 192 (0xC0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Duration : 2h 19mn
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Stream size : 382 MiB (1%)

Here is the results from one of the other good clips


General
Complete name : V:\Premiere\Wash U\Footage\Tricaster\8-27-10\8-27.mpg
Format : MPEG-PS
File size : 7.90 GiB
Duration : 1h 11mn
Overall bit rate : 15.9 Mbps

Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : [email protected]
Format settings, BVOP : No
Format settings, Matrix : Default
Format settings, GOP : N=1
Duration : 1h 11mn
Bit rate mode : Variable
Bit rate : 15.2 Mbps
Nominal bit rate : 25.0 Mbps
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:2
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 1.470
Stream size : 7.55 GiB (96%)

Audio
ID : 192 (0xC0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Duration : 1h 11mn
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Stream size : 195 MiB (2%)

Don't know if that will help anyone but I thought that it would not hurt...

Phil

SBowie
09-02-2010, 11:14 AM
Having kicked this around a bit here, it seems possible that the problem file may have resulted from the record function failing to exit properly (unless you actually powered down) after the people left. Failing similar reports, it may be hard to repeat this in local testing. :(

skdvr
09-02-2010, 02:51 PM
Hmmm, not sure I'm following you. Here is workflow at the end of the event. When the College staff walked out of view from the camera I stopped the recording, and the file does end as soon as they walk out of frame. The TCB was left on with a static wide shot of students leaving. When I was finished with the broadcast I faded to black and then switched to the Admin mode to transfer files from my back up recoding device (CitiDisk HDV) to an external HDD. While that was transfering I did loose my power that was being fed to me, but that should have only affected the files that I was transfering from the CitiDisk to the external HDD. I was just using the TCB in admin mode to facilitate the transfer.

Thanks again for looking into this...

Phil

SBowie
09-02-2010, 03:13 PM
If you stopped recording and transferred the file shortly afterward, then shut the machine off, then my notion wouldn't work. In that case, we'd have to suspect a file was somehow corrupted.

But if record module could have unintentionally continued for some lengthy period afterward (even though you deliberately ended recording), the file might actually be half full of 'black video'.

skdvr
09-02-2010, 03:24 PM
It is Odd to me that it is SO much bigger than the other 1 hour programs, if it was just black at the end I could see it more than the black being after every frame of video. Just one of those things I guess. Well at least that is what I thought after the first time it happened.

Thanks again.
Phil

treshawks
09-08-2010, 04:27 PM
Could it be that the problem file was recorded as Profile Studio and the successful files were recorded as Regular Studio?

I'm having a similar issue with a 1+ hour file 1920 x 1080 recorded set to Profile Studio on a TCXD300. Except I'm not having black frames. I'm just having trouble importing into FCP, converting the file(even with Speed Edit2). Each time I set up custom presets to export as 1920 x 1080 it reverts back to 720 x 480. I'm new at this though so take these comments with a grain of salt. I did confirm through properties that the recoded file is 1920 x 1080.

I did find out that VLC will play the file. But I'm still trying to get it converted to something FCP will import. I do have the quicktime mpeg2 plug in installed.

SBowie
09-08-2010, 04:39 PM
Each time I set up custom presets to export as 1920 x 1080 it reverts back to 720 x 480.Unless you're hitting a previously unknown bug, you should be able to create an HD SpeedEDIT project to match the recording, then set the "Use Project Size" switch in the custom render settings panel.

ACross
09-08-2010, 10:29 PM
In general, because we use MPEG2 files you could actually literally rip the power cord from the computer and the file (up to the point that power was lost of course) would be written correctly to disk.

A problem however that I have seen more than once is that when copying the media off to an external location that the copy does not actually complete for several reasons (e.g. network connectivity is lost, USB drive is disconnected for a brief second.)

When windows copies large files, what it does is first pre-allocate the disk space required for the file. This means that if the copy fails for some reason the file looks like it is the correct size but might well have no data in part of it. The way to check whether this occurred is to open the file up in a hex editor and look if the end of the file basically is entirely all 0's ... from the symptoms above I would pretty much bet that this is the case.

A.

ps. If you have any way of getting me the file, I would be happy to look at it for you.

skdvr
09-09-2010, 04:55 AM
In general, because we use MPEG2 files you could actually literally rip the power cord from the computer and the file (up to the point that power was lost of course) would be written correctly to disk.

A problem however that I have seen more than once is that when copying the media off to an external location that the copy does not actually complete for several reasons (e.g. network connectivity is lost, USB drive is disconnected for a brief second.)

When windows copies large files, what it does is first pre-allocate the disk space required for the file. This means that if the copy fails for some reason the file looks like it is the correct size but might well have no data in part of it. The way to check whether this occurred is to open the file up in a hex editor and look if the end of the file basically is entirely all 0's ... from the symptoms above I would pretty much bet that this is the case.

A.

ps. If you have any way of getting me the file, I would be happy to look at it for you.

Not sure if you are talking to me or to the guy with the HD problem, but here is my response just incase you are talking to me...:D

I transferred the file from the Tricaster to an external drive but left it on the TCB. So I guess I technically copied it and not transferred it. The reason I did that is that I could put the file on a Windows machine to edit with Premiere. I decided to try to open the file on the TCB because I had noticed the Huge file size difference between it (a 2 hour clip) and several other 1 hour clips. That is when I saw that when it opened it showed it was almost 5 hours long. It opens fine in Premiere, I just could not edit it becuase it would bog down my machine. It also opens fine with VLC player and Windows Media player, and plays it just fine with no black clips. Only in the Edit Media window of the TCB and on a seperarte Windows machine that has Speed Edit on it, does that file open up and show that it is 5 hours long and has the black clips showing up. I had uploaded a sample clip to your server after I called tech support, but last I heard you guys where still "Looking Into It". I do not know of a way to get you a small sample of the clip in its original MPEG format without it being re-compressed, but if you want the full 2 hour clip I would be happy to put it on a HDD and mail it to you, as long as you would send the HDD back to me.

To the question about recording the other programs with the normal MPEG 2 profile. I thought that at first when I saw the size difference. But after looking at the files I could tell visually that they where recorded with the Studio Profile, because I think that the standard profile looks soft. Plus when I opened the files in Media Info it does show (As you can see above) that it is a 4:2:2 file and the standard MPEG format is 4:1:1.

Thanks again for the help. I would really like to get something figured out with this...

Phil