[MPlayer-users] Re: Playing xcd image files

[Jonathan Rogers]

Jonathan Rogers wrote:
> Specifically, the DATAFILE lines seem to have an incorrect format, 
> compared to the cdrdao manpage. What are the numbers starting with "#"? 
> Are they offsets? The manpage doesn't have anything like that. I'll 
> attach the TOC file mode2cdmaker generated.

I must have been really tired or out of it when I tried this before. 
Now, cdrdao has no problem with it. I was able to burn my sample onto a 
CD-RW using the TOC I sent before and play it with MPlayer's vcd:// URI 
syntax. Now I just need to try to put a big movie on a 80 minute CD-R. I 
guess I was on the right track before, but it was good to hear the 
encouragement that it had worked for someone else. Thanks for the help.

Now there remains the question of how this will affect reliability of 
the media. My hope is that while it decreases the bit-for-bit 
reliability, playback reliability may be slightly better. I have no data 
or experience to back this up yet, but I do have a logical reason.

When I mount the ISO-9660 filesystem on a CD-R, the OS's IO subsystem 
(or possibly the drive itself) uses the error correction on the media to 
deliver reliable data to applications. However, as soon as too many bits 
have been lost, it will probably fail completely, causing many attempts 
at re-reading the affected area and pausing data flow to the application.

On the other hand, when MPlayer reads from the raw tracks, the OS won't 
try to detect or correct read errors. When MPlayer gets corrupted data, 
it may be able to conceal the errors by leaving out a frame or sample or 
even a whole packet. The show will go on, with a slight annoyance, but 
there won't be a fatal error. From what I understand, this is the logic 
behind CD Audio and VCD being written using Mode 2. Of course, I know 
very little about Linux's CD reading implementation or MPlayer's VCD 
reading, so this benefit may not be actual.

Jonathan Rogers