DAT vs. MPG

[johneboy]

As the subject suggests, what is the difference between the DAT file that is on a VCD as apposed to the original MPG we put on it?
There are programs such as VCDGear that converts DAT to MPG.
Is the file actually re-encoded, or is the header info changed?

[adam]

The header info is just changed. Dat files contain an additional file header, other than that the only other difference I know of is just the name of the ext.

[johneboy]

The header info is just changed. Dat files contain an additional file header, other than that the only other difference I know of is just the name of the ext.

So in other words, i could just copy the DAT file off an existing VCD, rename the ext to MPG, and reburn as VCD?

[MOVIEMASTERING]

dat=mpg just rename it so

[johneboy]

dat=mpg just rename it so

so the programs that say that they convert DAT to MPG, just rename it?
or do they rewrite the header information?
and if so, whats the point?

[Redeye07]

So in other words, i could just copy the DAT file off an existing VCD, rename the ext to MPG, and reburn as VCD?

I've done just that several times with complete success. I also wonder what the significant difference is besides the extension.

[adam]

As I said before a dat and and mpg are not the same because the dat file has an additional file header added. Programs like vcdgear simply remove this header, though I'm sure its not nearly as simple as it sounds. Also there may be other differences as well, this is just all that I know of.

If you rename a dat to mpg you are changing nothing, the file is still the same. Most vcd authoring programs will readily accept a dat file and correctly author it into a new vcd. Presumably these programs recognize the existing file header and do not attempt to add another one. For safety's sake you should always just convert the dat to mpg because as I said before, they are not the same thing.