I bought a DVD player a while ago that said it could play CD-Rs burned with mp3 audio files. I recently popped a disc with some mpeg-format movie files on it into it and found it would also play those, although they didn’t always have sound. Is there some type of compatibility thing whereby any player that will play mp3s will also play mpegs? Are the two formats related somehow, or is this just a accident peculiar to my DVD player?
Many DVD players will play plain MPEG files, but don’t count on every MP3-savvy player being able to do it.
Are the file formats related? Yes. MP3 is short for MPEG-1 Audio Layer 3. VCDs and some DVDs use layer 2, or MP2 for short. The MPEG audio formats were designed to work with MPEG video. Some DVD players use an audio decoding chip that can deal with all layers of MPEG audio; some only deal with the layers in the DVD spec; and some don’t decode MPEG audio at all.
Every DVD player is capable of decoding MPEG-2 video in some form, and every player that supports VCDs is capable of decoding MPEG-1 video in some form. However, the DVD and VCD specs are pretty specific about the exact format of the video streams, and although most players are more lenient than the spec requires, you can’t count on every player being able to play every MPEG stream. They may be hardwired to only work with certain frame sizes, bitrates, GOP lengths, and various other technical details given in the DVD specs. Also, the MPEG-2 video on a DVD is inside a container called a VOB, which combines the video, audio, and subpicture data into a single stream. .mpg files are transport or program streams, which are incompatible containers that basically do the same thing. All DVD players must be able to split VOBs, but there’s no guarantee that they can split other container types.
Conclusion: An arbitrary .mpg file you find on the internet and burn to a CD-R is unlikely to have a video or audio track that perfectly complies with the DVD spec, and those tracks are in a container that DVD and MP3 players have no inherent need to understand anyway. Some of the components you’d need to decode it are present in every DVD player, but some of them are unnecessary for playing either DVDs or MP3s and therefore aren’t present in every player. But a lot of new players will play .mpg files anyway, because it’s not that much extra work to support them, and cheap off-the-shelf MPEG decoder chips will work with non-DVD video formats.
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If a DVD player will play MP3-CDs, can it also play MP3-DVDs?
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Sorry, Lizard, but that’s a question that’s been in the back of my head for a while.
Probably, but not always. Some players, like this Panasonic S35, will only play MP3s from a CD.