AC3 Issue

techsplorer · Post by **techsplorer** » Sun Dec 19, 2004 6:44 pm

Hello All,
I'm a new VideoStudio 8 user, enjoying the product. However, I am experiencing a strange issue (bug) with AC3 Audio. I also purchased the AC3 plug-in for VS8. Specifically, I need to be able to import footage from a DVD (typically a DVD+R or RW from a Philips DVD recorder that encodes Dolby Digital/AC3 audio). I can import the footage from the DVD fine (BTW, I like the fact that you can select specific chapter segments for import, or the entire DVD). When I work with the footage though, the following occurs:

When I drop the clip into the timeline, I CAN hear audio only when using "Project" mode, when playing back the entire timeline. Whenever I select "Clip" mode or try to preview the clip from the library, video playback occurs but without audio -- which obviously makes it difficult to do any audio-based trimming. Audio doesn't play back when using the Multi-Trim feature either... Any thoughts? fixes?

I'm running VS8 on a Gateway M675XL 3.2GHz laptop with 1Gb RAM, WinXP SP2, and I have all the latest patches for VS 8 installed from the web site.

-techsplorer
...there are 10 kinds of people in the world, those who understand binary and those who don't...

david reece · Post by **david reece** » Mon Dec 20, 2004 1:52 pm

have you taken your clip from a copyright protected DVD?

this may be why it wont playback!

techsplorer · Post by **techsplorer** » Tue Dec 21, 2004 2:18 am

david reece wrote:have you taken your clip from a copyright protected DVD?

this may be why it wont playback!

Nope, just my own project video that I am recording live into a Philips DVD+R/RW recorder (DVR-75). (I'm archiving Betacam SP video footage from my Avid DS system to create a library of clips that I can edit using VS8 as a simplified video jukebox.) The DVD+R footage has AC3 audio and bought the AC3 plugin-in. I can import the footage fine and it even plays back with audio when I play the timeline in "Program" mode.

Basically, it's just in "Clip" mode that the AC3 audio doesn't play back. Very Strange.

My primary goal in all this is to end up with an archive previewing system that uses MPEG2 clips as source material to minimize storage space. (BTW, I evaluated over 10 different software video editing programs in this category/price range and finally ended up selecting VS8)

So far, I got around the problem by encoding an MPEG2 clip with PCM Audio; the DVD recorder encodes audio in Dolby Digital (AC3). However, the reason I wanted to pull clips directly from DVD+R is to bypass the manual encoding process which is time consuming; I need to archive 40 1 hour shows!

rwindeyer · Post by **rwindeyer** » Tue Dec 21, 2004 4:32 am

techsplorer wrote:
So far, I got around the problem by encoding an MPEG2 clip with PCM Audio;

That may be the way to do it. To my knowledge: VS8 can "read" and "write" AC3 audio; when it comes to actual editing, it needs to be in PCM or DV format.

tjeppesen · Post by **tjeppesen** » Tue Dec 28, 2004 1:05 pm

Sorry to interrupt here with a newbie question.

I am having the same problem. I have a Sony DVD-camcorder, and it reocrds audio in AC3!
Question: have do I convert the audio from AC3 to PCM??

maddrummer3301 · Post by **maddrummer3301** » Tue Dec 28, 2004 1:28 pm

The reason you can hear the audio when selecting "PROJECT" is because VS8 is converting the audio from the source files to whatever your audio settings are for the "Project Properties".
The "Project Properties" are accessed by hitting <ALT+ENTER>. These
will be the properties VS8 will use to edit the footage. The choice for audio
will be either Mpeg or Lpcm audio for editing.

If you have the AC-3 pack installed somethings wrong. It should be playing
back the clips. It's not playing back the Dolby in the clips. VS8 is converting the AC-3 audio to your project audio properties and playing it back(So it sounds like).

There are settings in the UVS.ini file to set the dolby audio, below are my settings. I import from Sony's stuff (clips) no problem playing back clips etc.
Note: There are many sections in this setup file (Make a backup before editing if you need to edit the file). The section below is for the [VIODRIVER] section.

< Location of File > ( Enable Show Hidden Folders must be ON )

C:\Documents and Settings\All Users\Application Data\Ulead Systems\Ulead VideoStudio\8.0\uvs.ini
[VIODRIVER]
UleadVideoPlay=1
UleadVideoDecoder=1
UleadAudioPlay=1
UleadAudioDecoder=1
UseOnlineMuxing=1
MotionEstimate=20
DvdDashVR=1
PlayAC3=1
DecodeAC3=1
UleadAC3Encode=1
Advance=1
ActiveMPEGDriver=-1

Note the references to the AC-3 section.

Aen · Post by **Aen** » Tue Dec 28, 2004 3:51 pm

Hi, I'm also using a Sony DVD Camcorder with AC3. I tried the config change to be appended under the VIODRIVER section, but still cannot work. Any help is appreciated. Thanks.

THoff · Post by **THoff** » Tue Dec 28, 2004 8:27 pm

Aen wrote:Hi, I'm also using a Sony DVD Camcorder with AC3. I tried the config change to be appended under the VIODRIVER section, but still cannot work. Any help is appreciated. Thanks.

You can't just add those settings to the configuration file and expect it to magically decode AC-3 Dolby Digital, you still need a filter for it. You can either buy Ulead's AC-3 plugin so you can both decode and encode such audio, or you can download a free AC-3 filter from Free Codecs, and have decode-only capabilities.

glukow · Post by **glukow** » Fri Dec 31, 2004 3:28 am

Hi,

I also have recently purchased the AC3 plugin and initially could only hear the audio while playing the clip, but could hear and see the video when playing in the project mode. I have since corrected the problem by changing the "Instant Playback target" in the preferences-general tab. Initially mine was set to "dual head" but when i changed it to "Preview Window" my video clips are now displayed while in the clip mode.

Prior to writing this reply i went back into the preferences and changed the mode back to "dual head" hoping to prove my theory that this change is what fixed the playback problem, but the clip video still plays no matter what i change my "instant playback target" to now.

So in other words, i'm not positive this is what corrected the problem on my machine, but the problem is fixable, because it currently is now working for me. Anyone who is experiencing this problem please try and change the "Instant Playback target" mode and let everyone know if this is what solves the problem.

By the way, I purchased the AC3 plugin because I too use a sony DVD camera and needed the ability to import my video files.

I currently have two problems, Now that i can import my video with AC3, how to i render my video and have VS8 encode the audio to AC3? I haven't found the option to choose AC3 as my preferred audio format. Also, I shoot all of my video in 16:9, but when i import the video the properties show 4:3, so if i change the properties VS8 re-encodes all of the video even if i didn't make any modifications to it. Does anyone know if the video really is 4:3 or is the sony camera saving the video with the wrong aspect ratio? The mini dvd plays perfectly in my widescreen tv, so i think the dvd properties have the aspect ratio correct. I want all my video to be 16:9 but i don't want to re-encode my videos unless it's really necessary. Any help would be appreciated.

Thanks,
Greg

rwindeyer · Post by **rwindeyer** » Fri Dec 31, 2004 12:46 pm

glukow wrote: I currently have two problems, Now that i can import my video with AC3, how to i render my video and have VS8 encode the audio to AC3? I haven't found the option to choose AC3 as my preferred audio format. Also, I shoot all of my video in 16:9, but when i import the video the properties show 4:3, so if i change the properties VS8 re-encodes all of the video even if i didn't make any modifications to it. Does anyone know if the video really is 4:3 or is the sony camera saving the video with the wrong aspect ratio? The mini dvd plays perfectly in my widescreen tv, so i think the dvd properties have the aspect ratio correct. I want all my video to be 16:9 but i don't want to re-encode my videos unless it's really necessary. Any help would be appreciated.

When you go to burn your DVD, and select Share - Create Disk, just click on the cogwheel at the lower left of the burning screen (Project Properties). Select Change mpeg properties, then Custom. Under the General tab you can select Display Output Ratio (16:9) and under the Compression tab you can select Audio Format - Dolby Digital, with a sample rate as you desire (I go for 192).

Aen · Post by **Aen** » Mon Jan 03, 2005 8:37 am

Thanks, my problem was resolved after applying the AC3 plug-in.