7 Replies Latest reply on Mar 17, 2009 4:05 PM by Scout's mom

    Imported audio narratives

      Hi Everyone,
      I'm having an issue with imported voice-over narratives in Captivate 2. I'm working on a Hugh project with a large number of studio recorded voice-over narratives. The audio is in an MP3 format.

      When I import the MP3's Captivate 2 converts the audio to WAV format. And in this process increases the volume level of the audio, significantly. This has caused a big issue with the 30 + simulations I've created which are being inserted into an elearning course. There is a distinct difference between the audio levels in the Captivate 2 segments and the same audio being incorporated into the other courseware.

      I've read that Captivate converts WAV files to MP3 format, but not the other way around. That is partly why we requested MP3 format over WAV. When publishing the simulations the audio is converted back to MP3's in the final SWF simulations.

      My problem is this, I have no way to knowing how much Captivate increased the volume level. I've been guessing at the percentage of volume increase, having decreased it several times. But still the client is not satisfied.
      Is there a solution to this? Has anyone experienced this before and have a recommendation?

      Our last resort will be to export audio clips from each Captivate 2 simulation and have a professional audio tech analyze the decible levels and give me a percentage for each simulation to decrease the volume. Quite an expensive solution!

      Is this a known bug in Captivate 2?
        • 1. Imported audio narratives
          Charlotte --
          I don't know that I have a true answer or solution, but I thought I'd post some of my own information in case it helps you figure out what's going on.

          We also have our audio recorded by a professional talent in a sound studio. When I provide the studio with the script, I instruct them to deliver the audio as "44,100 Hz, 32-bit, monaural recordings (normalized to max. -3dB) MP3 files."

          The key instruction there may be "normalized to max. -3dB."

          Whether I play the MP3 files using other software, on a handheld device, or after embedding them in Captivate 2, I don't hear any appreciable difference in the volume of the clips. For that reason, I suspect that Captivate is maybe attempting to normalize the volume of the clips you're importing -- perhaps it perceives them to be too quiet and is normalizing the clips (amplifying them) upon import.

          That wouldn't ordinarily be a bad thing, except if maybe you started out with clips that Captivate didn't normalize (for whatever reason) and had adjusted the volume manually. Then of course you're caught in a cycle of fighting Captivate to get all the clips to the same volume.

          I haven't heard of this issue as a bug, but fear it might be an intended "feature" that's working against you in this case.

          I'm interested in hearing other people's experience on this one!
          • 2. Re: Imported audio narratives
            Captiv8r Adobe Community Professional & MVP
            Hi all

            I really don't have any real data to back me up on this, only a gut feeling. I saw Charlotte say the following:

            I've read that Captivate converts WAV files to MP3 format, but not the other way around.

            Actually, I do believe it goes both ways. If you point at a .WAV file, you see a conversion occur as the .WAV is converted to .MP3 format. And the same goes with .MP3. Bring in a .MP3 and it gets converted to .WAV. The key note here is that inside the Captivate .CP file, audio has to exist as both formats (.MP3 and .WAV). I further understand that when you publish your project to create the final output, only the .MP3 is actually used.

            This leads me to believe or conclude that the .WAV format may only be needed for the purposes of using Captivate to make edits to the waveform.

            I further assumed (probably mistakenly) that as long as you never used Captivate to actually edit the audio, the .MP3 would simply be left alone and shipped right back out the door just as it came in. Actually, this would seem to make logical sense. Why convert files during both input and output? So I suppose my question here would be to ask if at any point Captivate was used to Edit the audio. Maybe by clicking Audio > Edit Timing...?

            Cheers all... Rick
            • 3. Re: Imported audio narratives
              rbLearning Level 1
              Excellent point Rick!

              I can follow up by saying that I virtually never use Captivate's built-in editor to touch a sound file.

              So, your assumption that Captivate "ships it back out" untouched seems quite reasonable:

              If my MP3 files always sound perfect (and I'm not touching them) --
              but Charlotte's sound "bad" (and she's editing them in Captivate) --
              perhaps that is the source of the trouble.

              Charlotte might help us nail down the cause by doing a little experiment:

              1) Select an MP3 file that sounds good to start with, but you already know ended up too lound in some published Captivate file.

              2) Import it into an empty project and immediately publish it (without editing the audio).

              3) Start a second new project, import that same audio, and do a little editing on it (delete part of it or whatever) before publishing it.

              4) Compare the two results. Does the volume of the first file remain the same as the original MP3 file, but the volume of the second one is much louder than it started out?
              • 4. Re: Imported audio narratives
                I have the same problem. I've repeated the steps exactly as rbLearning has recommended, and Captivate still seems to change the audio. The audio seems to be normalized, but results in clipping. As a result, the quality is far far worse than the studio recording that I paid good money to have professionally done.

                Even if I process the audio (using Audacity) to normalize so that the max db is -8.0 (or even higher... I've tried several settings), Captivate (3.0) still does something to the audio to make it very unpleasant.

                Any other recommendations?
                • 5. Re: Imported audio narratives
                  We're experiencing the same problem. I carefully encode the audio files direct from ProTools. I don't trust Captivate to manage the encoding settings automatically. Ideally, I don't see why it can't just pass the audio through without touching it.

                  In our course
                  - We begin with a Flash intro piece.
                  - We then move into the course produced in Captivate.
                  - We close with a Flash piece.

                  The audio in Captivate is much, much louder than the custom Flash pieces, despite the fact that we used the same audio files. So Captivate is definitely doing something to mess with them. I can't figure out if it's part of the importing process, the publishing process, or the playback, but this is a serious problem for sure.
                  • 6. Re: Imported audio narratives
                    Captiv8r Adobe Community Professional & MVP
                    Welcome to our community, Jnad2

                    For you and anyone else experiencing these issues I cannot stress strongly enough how important it is to report them to Adobe as possible bugs.

                    Click here to view the WishForm/Bug Reporting Form

                    I was once advised that if you imported audio to Captivate in MP3 format that Captivate didn't touch it and it simply passed through unless you decided to edit it. Looks like one of two things has happened.

                    1. I was provided with inaccurate information
                    2. The playing field changed with Captivate 4.

                    If you haven't tried it, have you tried importing the audio in MP3 format? If not and you do, are the same results obtained or are things better?

                    Cheers... Rick
                    • 7. Re: Imported audio narratives
                      Scout's mom Level 2
                      My experience is that wonky things happen to MP3 files: tinny sound, volume problems, etc. In C2 and C3, I assumed the files were being re-compressed. (I don't know what happens in C4). I always import WAV files and let Captivate convert to MP3 with very good results.