Bad sound quality from avi's to DVD w/both Toast or XiliSoft DVD Creator?

[NoMoPackers]

Thank you for reading. So as not to waste anyone's time...i will try to gie as much info in this post as i can.


iMac Intel 2 GHz Core 2 Duo
2 GB RAM
Mac OSX 10.4.11

I have been trying to convert avi's , downloaded with Firefox tool "Download Helper" (very nice add-on if you haven't tried it) to DVD, using Xilisoft DVD Creator for Mac. I always test the file by playing it on my computer first, usually with QuickTIme, to make sure the quality is worthy of putting on disc, sometimes the sound and video isnt synced, etc. However, when I play it on my computer, it sounds terrific.

Xilisoft DVD Creator does a fine job of converting these files to VIDEO_TS folder and burning it to disc. Sometimes it is rather slow, but it does the job, while maintaining the video quality quite nicely. I have found that simply dropping an avi on Toast and directly burning a DVD (Toast does the converting), well...Toast doesn't manage to maintain as good of video quality. So, I prefer to use Xilisoft. But i did notice the following problem with both softwares.

When I play these DVD's back, the sound quality is vastly amplified and distorted. There are no preference settings in either of these programs (Xilisoft or Toast) to affect the sound quality, so I am not sure why it would change in the first place.

Is there a simple way to fix this problem? I rather enjoy the ease of the default settings for these programs, as they meet my standards. I am not savvy when it comes to working in "Terminal" mode or changing around a bunch of parameters numbers.

Any advice would be greatly appreciated.

Thanks,

Dana
NoMoPackers@gmail.com

[tomlee59]

I've never used that particular software, but it sounds from your description that it is one of those "easy to use" packages that gains its ease of use in part by taking total control of the process. The risk is that it might not make satisfactory choices, and the "total control" part might mean you can't tweak anything.

The first thing to check is whether there is a hidden "advanced features" option that you can unhide. If so, look for options like "audio bitrate" and "gain." If you are getting distortion due to excessive levels, cut back on gain. If the distortion is due to compression artifiacts, increase the bitrate.

If there are no such options, then you have a couple of choices: Ditch that software, or do some intermediate tweaking with another package. In that latter case, you have (once again) many options. My favorite is to use Audacity (free, feature-filled, easy to use) to perform most audio-related tasks. It has a Normalize feature which allows you to set the peak level to a safe value (0 dB). You can then export in a number of formats. Most DVD authoring tools will happily accept audio in .wav or mp2 formats, both of which Audacity will generate. If you choose this route, post back, and someone can walk you through how to choose parameters, etc. for whatever DVD authoring software you end up choosing (if you choose to use something else). It's not hard at all, but if you've never done it before, the number of choices can seem a bit intimidating.

[NoMoPackers]

THanks for replying so quickly.

Actually, Xilisoft is a rather reputable software, from what I've seen. They have many audio/video products for various tasks.

However..
I have tried doing conversions to other formats with other software, and the probem i run into is that the sound then ends up out of sync with the video (perhaps because of my lack of knowledge of the bitrates i should be setting to coincide with the video). Tried all kinds of other formats there were to choose from.

Does that pose any new ideas?

Thanks

[tomlee59]

I wasn't intending to demean the software -- it's just that some of the more "powerful" tools rob the user of the ability to customize things in those cases where things don't work out. In other cases, the flexibility is actually there, but hidden within advanced/expert menus, etc. And if you're like me, you've never actually read the manual.

In any case, sync errors are extremely common, and can be caused by many different things. If there is a framerate mismatch, that can cause serious problems, depending (again) on how smart the encoder is. For fewest problems, select the target framerate equal to the source framerate. Of course, in order to be DVD compliant, you actually have only a small set of allowable values.

Mismatched bitrates in the audio stream are rarely the cause of subtle sync errors, but if you are getting very large sync drift rates, that's a possibility. If pitches are off, then that's a smoking gun. Again, smart encoding software should not have a problem with these factors, but not all software is bug-free or as smart as we'd like (or sometimes too smart for us!).

If the video originally derived from a live source (particularly off the air, or off of tape), noise and dropouts can cause jumps or drifts in sync. These require manual editing in order to repair.

If the sync drifts at a constant rate (meaning, the sync time difference increases linearly as time progresses), Audacity can fix things up with its "change tempo" feature.

If the sync is offset by a fixed amount, Audacity can insert a silence of a duration you select (or alternatively remove a snippet of audio) to resync things. I find it frequently necessary to use Audacity in these ways to fix up sync problems.

[MacDSL]

Yes, the simple way is to turn the volume on your TV up or down to suit your taste..

There is no simple way to "normailze" the volume across multiple videos you download from the Internet that I am aware of.

[Herve]

hello

the sound quality is vastly amplified and distorted.

Do you have a link to one of these avi?

There is no simple way to "normailze" the volume across multiple videos you download from the Internet that I am aware of.

Try the command line tool "Normalize", it owns a batch processing (average audio normalization with multiples files)

bye

[MacDSL]

The CLI Tool Normalize works across different formats of video/audio files?

[Herve]

no, but his aim is to convert to DVD.
so he extracts the audio to a Normalize compatible format (wave for example) and normalize all the files together
(…and encodes them to ac3 and mux them with video part)

bye