unhappy user on sv-av100 forum

[bjoraker]

Found this post on dedicated Panasonic sv-av100 forum following my post on videoredo and how much I like it. Any comments?

http://www.jackbrown.us/camera/

I gave this prog a try in order to merge mpeg2 streams from my AV100.
What struck me and why I cannot recommend it:

Before merging, I counted the amount of frames of the two seperate streams. I merged the two streams with this program and the amount of frames in the new merged file does not correspond to the sum of the two seperate files ! Strange...

Therefore, I stick to tmpge which has a mpeg-merger as well. Also no re-encoding. I checked that with Avicodec http://avicodec.duby.info

Thomas Scheen

[DanR]

I wish I knew how many frames were lost, but my guess would be just a few. When you merge two files, VideoReDo will often drop a few frames from the end of the file. It does this on purpose. Here's why:

In an MPEG program stream, the audio packets are usually offset by 100-500 msec from the video packets. Therefore, when you reach the end of the file, you have video packets without corresopnding audio packets. This is undetectable when the video is played back.

VideoReDo will drop the final few frames for which there is no corresponding audio. It does this so that the next segment is guarenteed to start out in sync. You can count frames, but the real test is what happens when you burn the resulting merged file to a DVD. You can check around on other msg boards and you'll find many cases where the output of other merging tools playback fine on a software player but create sync problems when burned to DVD.

The original author of this message didn't say whether or not frames were removed because VideoReDo tried to correct sync errors in the original file. This is another possibility, but probably less common on a digital camcorder.

If you haven't given VideoReDo a try, please do so and let me know if you think there's a problem with the merge function. If there is, I want to know about it so it can be fixed.

[Anonymous]

Dan, Mea culpa - You were right !

It was only yesterday that I discovered that the joiner function of Tmpgenc is buggy. I did the following test:
I recorded a 30 sec clip (where one can see myself clapping my hands)with my AV100 and copied it 20 times. I joined the 20 clips with tmpgenc and discovered: After 2 to 3 min., the sound gets out of sync. Quite drastically after 10 min. (about 0,5 seconds) which is of course absolutely inacceptable.
Did the same with Videoredo and no problems at all (except for the cumbersome File-chosing process, see my posts in Support)

Anyway, thanks. Happy AV100 user now.

Thomas Scheen

[DanR]

Thomas, Build 220 is available now for testing and it addresses your issue with the joiner. If you open the windows explorer, select multiple files and drag them to VideoReDo or its desktop icon it will add each of the files to the joiner automatically.

[Anonymous]

It works. And quite fast I must say.
According to which criteria are the clips put into the joiner-list ? Would it be a lot of work to put the oldest (date & time from file properties) mpeg-clip first in the joiner list, the second-oldest second and so on ?

Anyway, I really appreciate your Easter-Overtime-Work.
Thanks a lot,

Thomas Scheen

[DanR]

According to which criteria are the clips put into the joiner-list ? Would it be a lot of work to put the oldest (date & time from file properties) mpeg-clip first in the joiner list, the second-oldest second and so on ?I just did some additional testing and there doesn't appear to be any particular. In my initial testing, they were always added alphabetically, but that appears to have been coincidental. I'll look into sorting the files, at least by name. Not sure about date/time.