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-   -   MPEG Layer II audio is not officially supported by NTSC (http://www.digitalfaq.com/archives/encode/14193-mpeg-layer-ii.html)

sparskter 04-05-2006 02:58 PM

MPEG Layer II audio is not officially supported by NTSC
 
Hello there :D
Quote:

MPEG Layer II audio
The MPEG Layer II format (commonly using the .MP2 or .MPA file extension) is not the same as the MPEG Layer III (MP3) audio format. While both forms of MPEG audio, they are not the same. DVD and CD-based video does not use MP3 audio. For NTSC video, MPEG audio is not officially supported. This being said, also realize most DVD players can playback the MPEG audio. If the player can play S/X/VCD formats, then it will most likely playback the MPEG Layer II. Most MPEG video chips are also hard-coded to play the audio. For PAL users, MPEG Layer II is currently supported, though recent shifts in the DVD Forum has hinted that this will change in the future. The biggest advantage to leaving the audio as MP2 is to preserve it's quality, assuming it was clean sounding from the beginning. Encoding to PCM merely makes the file larger and encoding to AC3 can potentially harm the quality, especially if the MP2 was a low bitrate. In general, using 256k 48hz is optimal. And 192k is minimum. Most X/S/VCD formats used 224k.
Advantage: size and ease of conversion from XVCD/SVCD/CVD/VCD
Disadvantage: quality and player support
http://www.digitalfaq.com/dvdguides/...burn/intro.htm

For NTSC video, MPEG audio is not officially supported
For PAL users, MPEG Layer II is currently supported

Could anyone confirm this please ? If it is true or not, both sentences above.

best to all

sparskter

Dialhot 04-05-2006 03:50 PM

All that is true.

kwag 04-05-2006 07:31 PM

Re: MPEG Layer II audio is is not officially supported by NT
 
Quote:

Originally Posted by sparskter

For NTSC video, MPEG audio is not officially supported
For PAL users, MPEG Layer II is currently supported

Could anyone confirm this please ? If it is true or not, both sentences above.

FALSE :!:
MPEG audio is defined in DVD specifications :arrow: http://www.dvddemystified.com/dvdfaq.html#2.4.12
Correct facts are always here: http://www.dvddemystified.com/dvdfaq.html
Quote:

[2.4.12] Is MP3 compatible with DVD?

Not officially. MP3 is the MPEG Layer 3 audio compression format. (MP3 is not MPEG-3, which doesn't exist.) The DVD-Video spec allows only Layer 2 for MPEG audio (MP2).
-kwag

Dialhot 04-05-2006 07:43 PM

Karl, read carefully : what is said is that the layer 2 is the only layer authorized for MPEG Audio on a DVD. It is NOT written that MP2 enters in the spec for ALL format of DVDs.

And NTSC DVDs do not have MP2 in their spec.
See part 3.6.2 au DVDDemystified :
Quote:

MPEG audio is not used much on DVDs, although some inexpensive DVD recording software programs use MPEG audio, even on NTSC discs, which goes against the DVD standard and is not supported by all NTSC players.

kwag 04-05-2006 07:51 PM

Quote:

Originally Posted by Dialhot
Karl, read carefully

Yes, I did :D

Quote:

MPEG audio is multi-channel digital audio, using lossy compression from original PCM format with sample rate of 48 kHz at 16 or 20 bits. Both MPEG-1 and MPEG-2 formats are supported. The variable bit rate is 32 kbps to 912 kbps, with 384 being the normal average rate. MPEG-1 is limited to 384 kbps. Channel combinations are (front/surround): 1/0, 2/0, 2/1, 2/2, 3/0, 3/1, 3/2, and 5/2. The LFE channel is optional with all combinations. The 7.1 channel format adds left-center and right-center channels, but is rare for home use. MPEG-2 surround channels are in an extension stream matrixed onto the MPEG-1 stereo channels, which makes MPEG-2 audio backwards compatible with MPEG-1 hardware (an MPEG-1 system will only see the two stereo channels.) MPEG Layer 3 (MP3) and MPEG-2 AAC (also known as NBC or unmatrix) are not supported by the DVD-Video standard. MPEG audio is not used much on DVDs, although some inexpensive DVD recording software programs use MPEG audio, even on NTSC discs, which goes against the DVD standard and is not supported by all NTSC players.
From the above paragraph:

"Both MPEG-1 and MPEG-2 formats are supported."

Or:

"which goes against the DVD standard"

Now, which is the correct definition, if the document contradicts itself :?: :lol:

-kwag

Dialhot 04-05-2006 08:27 PM

If the document is inconsistent then stop using it as the holy bible ;)

Since the DVD is born, that means a lot before the usenet FAQ has been compiled into the "DVD Demystified" document, the MPEG Audio is out of the spec for NTSC DVDs.

Beside this, it's a well known fact that Philipps threaten to leave the DVD consortium if it does not accept to put MP2 in the spec of the PAL disc.

Go on the MPEG.org site, and read the title of the documents that have been written on this toppic (unfortunately the documents themselves are not anymore available :-().

http://www.mpeg.org/MPEG/dvd.html#dvd-resources

Quote:

MPiG (Dolby vs. Philips audio war) by Espen Braathen
Wanna know why the DVD consortium decided to use different audio standards for PAL (Europe) and NTSC (USA/Japan) DVD discs ? That all because of Philips greediness!
To be more accurate, on the same site you will also see that MP2 is optional on NTSC disc, the same way as AC3 is optional on a PAL disc. That means that a NTSC player is not mandatory to play MP2 streams because such disc MUST have an AC3 stream, but that mean also that you can find MP2 on an NTSC disc.

http://www.mpeg.org/MPEG/DVD/Book_B/Audio.html

Note that since this initial definition have been made, the situation has changed as PAL producers definitely droped the MPEG2 audio for their disc.

kwag 04-05-2006 11:49 PM

That's pretty screwed up stuff :roll:
Thanks for the info and clarification Phil :)

-kwag


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