Experimenting with playing ISO files Options

[JustSumGuy]

Some people on this board report that they can't play some or any ISO files with their WDTV players. I, personally, haven't yet seen any instance in which the WDTV player won't play an ISO file at all, but several of them don't seem to play correctly. Note that this means some ISO files play perfectly on my WDTV right now (I'm using the latest official firmware that came out at the end of April 2009).

As for those that don't seem to play correctly, here's an experiment I've tried...

(1): I ripped a DVD (let's call it "Movie D" to distinguish it from A, B, and C, which play fine) onto one of my computers' hard drives (most of my machines run Windows XP Pro / SP3). The output was in normal VIDEO_TS/VOB folder format on the hard disk.

(2): I created an ISO copy from that DVD folder using ISOBuster.

(3): I played both the DVD folder and the ISO file using VLC 1.0.1 on my computer. They both played perfectly there.

(4): I copied both the DVD folder and the ISO file to the external disk that I then connected to my WDTV.

(5): The DVD folder version of "Movie D" played fine on the WDTV.

(6): When I played the ISO version however, it began playing properly, but before long it seemed to choke and sputter. The symptoms were much like you'd see if you tried playing a dirty DVD disc in a standalone player or on your computer: unexpected pauses, many dropped frames in a row, audio drop-outs, and other visual and audio artifacts.

I don't know why this occurs, but I don't see how it could possibly be a codec-related issue since the DVD folder format version plays perfectly.

I'll be performing additional experiments in an effort to find out, though. For example, I'm going to try different ISO creators, specifically UltraISO, to see if that makes any difference. I'm also going to explore more deeply to see if I can find some way to distinguish ISO files that play fine and those that don't.

One hypothesis I'll be exploring is whether or not disk fragmentation plays a role. Perhaps the problem I'm experiencing playing "Movie D" in ISO format arises because the NTFS file segments are spaced too far apart on my 1.5 TB disk. I'll test that by performing a Disk Keeper defrag and trying it again (but that takes a long time for a 1.5 TB disk, so I don't know when I'll be able to try that...)

If and when I learn anything useful, I'll report back. If anyone has any ideas or other thoughts to contribute, I welcome them!

[JustSumGuy]

Well, I'm still having the same problems playing some ISOs as well as some traditional DVD folders (i.e, VIDEO_TS) using my WD TV. I tried defragmenting the hard drive, but it made no difference.

But DvDrmann's comments have rung a bell: The only ISOs and/or DVD folders that don't play properly have all been ripped from DVD-9 or Blu-Ray discs. In other words, they were all from dual-layer discs. Why this should cause the problems I'm seeing I don't know, even though I've very recently learned that the placement of the layer-1 to layer-2 split can be extremely important when one copies a ripped dual-layer DVD back to blank media.

The other complicating factor is that not all the ISOs and DVD folders ripped from dual-layer discs cause the playback problems I'm seeing with a subset of them. Some of them play fine, but, for example, Battlestar Galaticta's Razor has horrible playback problems (that are not related to copy protection) such as infinitely repeating one part of one scene about 10 minutes into the program. It will NOT play properly on the WD TV no matter what I try, although it plays fine on a backup DVD copy (confirming that copy protection is very probably not involved). Note that Razor will not play properly on the WD TV in either ISO or DVD Folder format.

Any suggestions?