Artifacts and Defragging.

[bmiller]

I backed up a disc yesterday and when i played it in my Oppo there were 2 spots in the first 20 min. where there was a small line of artifacts that lasted about 2 sec.yet the audio disappeared. i was able to hear the audio when i stopped and rewound until a point just after the artifacts disappeared. The audio then played ok. When playing in powerdvd the audio was always there regardless of the artifacts. The oppo appears to be more sensitive.
I then started again. I created a BD50 .iso. I then defragged this drive. I then compressed and created a BD25 .iso on the second drive. I then defragged this drive. Checked video with powerdvd and artifacts have disappeared, at least in the spots where they were before. It appears keeping the disc defragmented before compressing and burning helps in reducing artifacts and audio drop outs. This may help some others who have run across this problem.

[Complication]

I suggest you look at the quality of your media and the speed of your PC. Any fragmentation in the files on your hard drive would automatically be removed when written to the actual DVD/BD disc so your Oppo would not be affected. Any errors on the disc are likely caused by bad media, the writer (fireware update?), or your PC's inability to keep up with the writer. It used to be that a writer would just error out in the middle of the process when your system could not keep up but now they just try to mitigate the problem and may create errors instead. Similar to your writer, PowerDVD would be affected by fragmentation if the I/O on your PC or hard drive is not able to keep up with the demands of playback (especially relevant in Blu-Ray).

The bottom line is that defrag is not generally related to being able to write a disc correctly, but it might be helping just enough on your system to allow you a better burn and/or PowerDVD playback. For most others it would not really help.

[bmiller]

I forgot to mention in my previous post that the .iso created by Dvdfab had the artifacts, and were not created from burning. After i played the BD25 burned disc and found the problem, i mounted the iso and played it with powerdvd. The artifacts appeared in exactly the same spots. I deleted the BD25 .iso created with dvd fab and proceeded to start all over. This time defragging as i went along. I played the newly created .iso produced by dvdfab and voila, no artifacts. I then burned the second disc, and no artifacts. maybe this is just coincidence, but i think i'll continue defragging.
I'm sure a lot of super fast newer pc's will be able to handle the massive amounts of data from Bluray much better than mine.