Jerky at the end

[jeffoz1]

Hi, just bought the 840G TDK dual 8x+ 4x- burner and noobie to DVD copying although I’ve done many a VCD. I’m experimenting with DVD-R media with mixed results.

However the TDK DVD+RW 4x media burns and plays OK on my PC and standalone but seems to struggle toward the end of the disk. Here’s what I’ve done. I ripped DVD using Decryptor and burned the image file straight to the disk. It fits without re-encoding although the disk is almost full.

When I play back on the PC using Roxio’s DVD Max, the final chapter becomes jerky but it does finish. On the standalone, there is no jerkiness but it stops about five minutes before the end.

I’ve copied the last VOB from the disk back to the HD and it plays fine on DVD Max right to the end so the file on the disk is OK.

Wondered if anyone can shed some light on this as to whether the media or the burner is suspect. I would have thought that the burner and media coming from same company that I would not have this problem. I’ve enabled DMA and I’m not using labels. Thanks

[rcb]

you mention that your disk was almost full.

If you are getting close to the 4.3 gig disk capacity, that could be yuor problem. Some disks just don't do well when loaded to the "brim".

You might try a re-burn after shrinking back to around 4.0 gig and see how things go. Dvdshrink can do that job.

[jeffoz1]

Thanks rcb, you're right! I erased the +RW in question and put only the last VOB on by itself and the PC played it Fine.

My conclusion is that data on the outer rim of the this media must be slower to read in real time causing the jerky motion. Files are not corrupt however as I can copy them off the disk. I notice that DVDInfo shows the format to be non DVD-Video. I'll try some other burning settings.
Cheers

[jeex]

i've burned 4.38gb on a recordable dvd with no problems, most of the time.. the times when the problems do arise is when you use poor media..

i would suggest trying;

ritek
apple
verbatim (non-CMC)
tdk

there is other quality media out there that will work. and the problem with your disc may not happen in other players.. but i've never had a problem with the media mentioned above crapping out towards the end.

and your theory about data being read slower at the outside of the disc is completely false, it is actually read faster.

[whomacuddy]

I've had this problem with only RW media both +RW and -RW where the data becomes more difficult to read at the end particularly on stand alone players and older DVD-ROM Drives .

[instigator_008]

and your theory about data being read slower at the outside of the disc is completely false, it is actually read faster.

Are you sure? Elementary physics say that the outside edge of any circular object in rotation spins slower than the inside edge.

Either way, as you say its not that that causes the jerky video. oor media causes jerky video at the edge of the disc.

[whomacuddy]

The data is read faster as the disk rotates at a fixed RPM regardless of where abouts the disk is being scanned the outer edge is read faster as the circumference of the laser's circle is larger , so 3000RPM on the inside covers less data than 3000RPM on the outside of the disk , I believe CD Audio disks compensate for this by slowing down as they approach the outside .

[jeffoz1]

Thanks for all the inputs. I've tested and the jerkiness is caused by slower reads (the file is not corrupt when picked off). Whether it's due to dynamics or error-correction algorithms working overtime I'm not sure.

[garryheather]

The data is read faster as the disk rotates at a fixed RPM regardless of where abouts the disk is being scanned the outer edge is read faster as the circumference of the laser's circle is larger , so 3000RPM on the inside covers less data than 3000RPM on the outside of the disk , I believe CD Audio disks compensate for this by slowing down as they approach the outside .

As do DVD players, although buffers and variable bitrate can play a part in how much of this is discernable.

The same does not necessarily apply to DVD ROM drives where data is present, CLV, CAV and P-CAV all play a part here as to how fast the disc goes, and to a lesser extent when using +R, which adopts a different write strategy than -R which helps give it it's performance push in data applications when reading.