AC-3 versus MP2?

[rkr1958]

My question is simple ... How I got there was not ...

My question, which is better an authored DVD using the video (*.m2v) and audio (*.mp2) streams produced by a TMPGEnc Plus encode of captured DV AVI or an authored DVD using the video (*.m2v) from the encoded TMMPEG-2 and AC-3 audio stream encoded from the PCM audio stripped from the DV AVI?

How I got there ... My 3-year son has "The Letter Factory" DVD and "The Talking Words Factory" VHS tape from Leap Frog. Each run 30 to 35-minutes. For convience I thought I'd back them both up to DVD using TMPGEnc DVD Author. I ripped "The Letter Factory" DVD to my harddrive using DVD Decryptor. I then included the main movie into my DVD project. I noted that the video was CBR MPEG-2 at 8000 kbs and the audio was Dolby Digital AC-3 2ch at 192 kbs.

Next, I recorded "The Talking Words Factory" VHS tape to my DV camera via the A/V RCA cable. I then captured the DV AVI to my harddrive and encoded it using TMPGEnc Plus. I used the DVD template but "unlocked" it in order to increase the video bit rate to 8000 kbs to match the DVD rip. However, DVD Author refused to include the MPEG-2 into my project because it's mp2 audio did not match the AC-3 of the DVD rip.

After trial and error and some searching ... and to make a very long story not so long ... I De-Multiplex the encoded MPEG-2 into *.m2v (video) and *.mp2 (audio) streams. I used Gold Wave to strip to PCM audio from the DV AVI capture. (I assume I could have also used VirtualDub for this step instead of Gold Wave). I downloaded ffmpegGUI (freeware, tools > audio encoders) to encode the PCM to AC-3 at 192 kbs to match the DVD ripped audio. I found that I had problems with this encoding if I tried to directly encode using the DVD AVI steams instead of the PCM stream extracted using Gold Wave.

DVD Author accepted these *.ac3 audio with the *.m2v videosteams into my project with the main movie from the DVD rip. I authored and played the authored DVD using WinDVD. Everything played fine on my computer and so I then burned the authored DVD using Nero. (I expect no problems playing the DVD in my Settop player).

Anyway, I noticed that the AC-3 audio stream (at 192 kps) is 49,220 KB and the .mp2 stream produced by TMPGEnc (at 384 kps) is 98,440 KB. This got me wondering ... so my question ... Also a second question for anyone still with me ...

Should I always encoded my audio separate from my video when I convert DV AVI to a DVD? If so ... assuming I'd used TMPGEnc Plus for the video what's best for the audio and what settings should I use? Is ffmpegGUI ok?

Another question ... if I had encoded the audio to AC-3 at 384 kps whould DVD Author have accepted that with the DVD rip AC-3 audio which was at 192-kps?

All this was fun ... I learned something new tonight ...

[redwudz]

My personal opinion is that AC3 is better, but if the audio isn't critical to you, MP2 is a lot easier.

[johns0]

I think its better to encode all the audio to ac3 which i do with ffmeggui and its more likely to play on more dvdplayers than mp2 except for certain pioneer dvd players which dont like ffmpeg ac3.I rather encode at 192,384 is good but uses a little more space but might give a little better sound with dvd`s that need the dynamic range but heck i dont care myself,i rather use 192kbps ac3.