Losing audio data converting AC3 to MP3, Help!

[blueprint]

This is causing me to make xViD/Lamemp3 videos in which the video and audio length mismatch. It doesnt matter if i encode with the Lame codec or FrauhofferII, or which app i use to create the mp3, it ends up losing some ms. This is creating out-of-sync videos.

I've tried changing the sampling frequency from 48Khz to 44.1Khz, and different bitrates from 128Kbps to 320Kbps but no difference.

If i direct stream the AC3, the stream lengths match and sync is preserved.

I have updated FFDSHOW and the AC3 Filter/Decompressor but it still happens.

Does this sound familiar? Any suggestions?

[Soopafresh]

Save direct stream with AC3 so the audio is in sync.

Download the script in this thread and run the Avi_Gain_Regular.bat file on your AVI/AC3 file.

https://forum.videohelp.com/topic314909.html

That'll convert the audio to MP3 and remux it.

[blueprint]

Seems like you do everything with scripts Soopa, don't you do anything manually nowadays?

Lets see, Avi_Gain_Regular.bat u say...

OOOOOOOOOOOOOOOMMMMMMMMMMGGGGGGGGGGGGGGGGGGGGGGGGG GGGGGGGGGG

IT WORKED!!! Audio is the same length as the original...

Your MS-DOS .bat file just did what Cool Edit Pro/Soundforge/Audacity could not, and encode a wav/ac3 to mp3 with no file length change... Is the trick Normalising it?

I love you Soopa. I felt a tear swelling then!

Can u explain how that worked? Its pretty loud now, can i increase the volume only slightly? And why 224Kbps... any chance u can make me a new .bat with 128Kbps and just a small volume increase?

I'll be using AVI Gain for all my movie mp3 encodes now

[blueprint]

Proof:

[Soopafresh]

Sure thing, but you can change the info just as easily.

Just open up Notepad and open the .BAT file . Look for these lines:



and change to this (the "rem" command will disable the audio normalizing, so in theory it shouldn't be louder than the source any longer):



Thanks for your kind words, happy to help out.

[blueprint]

Cool that worked, theres only one problem. Your .Bat files seem to fill up the User Metadata with a heavy spam of the codec, in this case DivX, when i hover my mouse pointer over it, it goes off the screen.

Whats going on there? Can u fix? Or is there a way to delete the Junk data? Is it taking up much space?





Also from the things u are doing to the sound, can u summise why this mp3 encoder works properly and why everything else i use doesn't?

[Soopafresh]

Aha...That's the DivX Multiplexer at the end creating that garbage. Talk about giving themselves props. Bummer, because it is a really good muxer. If you don't absolutely need to change it, the extra junk might be worth the quality of mux. I think there are some apps out there that would let you clean it out.

Delete the blue line, and replace it with the green one.

[blueprint]

What is that doing, using the FFMpeg encoder instead? Okay, lets try it!

Thats no good, it created a VBR mp3 so i got a warning on loading and the length is different again... lol

Can u specify CBR audio?

Don't worry about the Junk Metadata, it gets erased if i do anything else to the file.

THANKYOU AGAIN 8)

[Soopafresh]

I sent you a PM on the syntax for using Mencoder as the muxer.