AVI with 128 Kb/s Audio Bitrate - What bitrate to use AC3

[allanc448]

I have a PAL AVI with 128 Kb/s stereo that I want to convert to play on my standalone NTSC DVD player that does not play DIVX.
I have successfully extracted, converted and played a 5 minute test using 448 kb/s as the bitrate for the audio.
My question is when converting the audio from WAV to AC3 using ffmpeggui should I be using the 448 or a lower value as the output bitrate?
Thank you in advance.

[Soopafresh]

As long as you have room for an audio file at 448K, it should be fine. That'll work for .AC3, but for some reason I recall you shouldn't go past 384K for MP2.

The ultimate test is to encode it at that rate and try it on your player.

[jimmalenko]

Soopafresh is correct re: MP2 = 384 and AC3 = 448. I guess the question is though, is 448kbps overkill for a 128kbps source ?

[ZippyP.]

224 should be OK for AC3 stereo, IMHO.

[allanc448]

As long as you have room for an audio file at 448K, it should be fine. That'll work for .AC3, but for some reason I recall you shouldn't go past 384K for MP2.

The ultimate test is to encode it at that rate and try it on your player.

The guide I was reading mentioned (in terms of the bitrate calculator) that 'AC3 was usually 448'.

[yoda313]

Hello,

I've done captures on my hauppauge wintv pvr 250 at 256 mp2 and it sounds just fine. Don't upcode it too much. You won't gain anything out of it and you'll actually take up more space that way too...

Kevin

[ZippyP.]

The guide I was reading mentioned (in terms of the bitrate calculator) that 'AC3 was usually 448'.

For 5.1 AC3 I would agree, more channels need more bitrate.

[monzie]

Use 192 (the default in FFmpeggui) in either Ac3 or mp2.....and as a bonus this setting seems to avoid synch problems (on 99% of all mp3 vbr's) so avoiding the need to convert to .wav first (believe me, I've been there got the T shirt etc etc)...you can always convert to wav then ac3/mp2 AFTER if you have synch probs on the odd 1% that doesnt convert in synch....just test in your AUTHORER before writing and burning.