Sefy's VCD vs SVCD: audio rate

[Giuliano]

I was considering that standard TMPEnc audio rating in SVCD for audio is 128 Kb/s, instead the Sefy's SxVCD one is 224.

Is it better to give that 100Kb/s difference to the video or to the audio ?
In a Dolby Pl downmixing from an AC3 source, worths the 100Kb/s audio the difference, or is it very difficult to hear it ?

thanks in advance.

Giuliano

[adam]

Well I don't know what version of TMPGenc your using but all my svcd templates have 224 as a preset for svcd. Anyway, yes it really can make a huge difference in quality, especially if you have a decent hardware setup. At 224 your audio will be near cd quality. 192 is probably acceptable, 160 is really pushing it and I would personally never go as low as 128 for anything worth watching. An extra 100kbits for video will not make a massive difference but it will help, whether or not its worth it depends on what priority you place on audio.

[Giuliano]

I Use TMPGEnc 2.52.34
And that' what i found in the SVCD template (PALversion)

MPEG.Audio.StreamType_ReadOnly = True
MPEG.Audio.SamplingFrequency = 44100
MPEG.Audio.SamplingFrequency_ReadOnly = True
MPEG.Audio.ChannelMode = 0
MPEG.Audio.ChannelMode_ReadOnly = False
MPEG.Audio.CantUseMono = True
MPEG.Audio.BitRate = 128000
MPEG.Audio.BitRate_ReadOnly = True
MPEG.Audio.CalcCRC = True

Any difference from yours ?

By the way: I knew that TMPGenc last 30 days, with MPEG2.
The statup window report only to be 14 day.
That's to say that also registrered useres don't have MPEG2 encoding for more than 30 days. Is it right ?

Giuliano

[Sefy]

I agree with Adam on this, audio at 224k sounds much better then 128k, especialy on a good home quality system, and if i have to reduce, i try to go as little as 192k and not below, unless the original source was already in low quality.

[mikehg]

Hehe...I must be tone deaf!...For standard movie dialog I can't tell the slightest differerence between 64K and 224K. In fact a few people that have watched the movies made remarks of how crisp and clear the audio was :)

[siaododo]

Yeah, I really couldn't tell the difference btwn 128k & 224k. All the XVCD's that I made have 128k for audio. I save the extra 100k for the video. I thought they sounded pretty good on my stereo system.

[Sefy]

I suppose this would be the same as NTSC and NTSC Film quality, some see it, some done, same with Audio, some hear the diffrence and some don't, as long as you are happy with the quality, that's the important part

[videoguy79]

I agree with Sefy; use whatever bitrate you feel is a comprimise between good sound and file size. When space is not an issue, I use 384kbps, 48Khz audio to take full advantage of my reciever. For mostly spoken dialouge, 128kbps is ok, though I would personally not use anything lower (esp 64Kbps, LOL!!). Remember that mp2 is not mp3. . .mp3 does better at lower bitrates than mp2 or mp1, so a 128kbps mp2 will not sound as good as a 128kbps mp3 (mp3 uses a MDCT transform and more complex spectral analysis than does mp2 or mp1) but a little better than a 128kbps mp1. According to the MPEG audio papers I have seen, CD quality bitrates are as follows: mpeg-1 layer 1: 384kbps, mpeg-1 layer 2: 224kbps, mpeg-1 layer 3: 128kbps.

[mikehg]

I think it depends a lot on the source and content of the film. Taking a clean audio rip from a DVD I'm sure produces better results at low bitrates. If the film is mated with a lot of High fidelity soundtracks, then I would definately go as high as possible. When I first started making Svcds I heard several people make comments about "maybe as low as 96k if you're desparate":) so I made several test clips about 5 minutes each at all available bitrates and burned them on a cd. I played each clip randomly while my girlfriend listened to see if it was just me or if there was a big difference. She couldn't tell the difference between any of them that contained normal speech. And funny enough she picked one with a music soundtrack that was 160K over the 384k.

Well, I'm done rambling....Take care,
Mike H.