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Does anyone know of a program tha we can buy or a company that will eliminate the background noise from a tape so all the jury hears are the two voices? I have a judge who says if the court reporter can't understand the tape first time she hears it it's not any good.
 
Posts: 334 | Location: Beeville, Texas., USA | Registered: September 14, 2001Reply With QuoteReport This Post
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You shouldn't alter audio for trial by simply using software. As with any alteration of original evidence, you need an expert who understands the software and the changes it makes to audio. Otherwise, you could create a new piece of evidence with no witness who can establish the predicate for its admission. It wouldn't work to simply tell the court that you used some software without being able to explain how it works.

Use DPS, FBI or a private company that specializes in cleaning up audio. There are lots of choices available.

I was not aware of the "my court reporter can't understand it" rule.
 
Posts: 7860 | Location: Georgetown, Texas | Registered: January 25, 2001Reply With QuoteReport This Post
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Fort Bend COunty SO also has some excellent equipment for this type of endeavor. Additionally, don't forget that Target stores have an immense crime lab in Minn, and they will selectively take LE cases from around the nation acc'd to their website.

John is right, you've got to have a witness to sponsor the enhanced tape or dvd.
 
Posts: 2578 | Location: The Great State of Texas | Registered: December 26, 2001Reply With QuoteReport This Post
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John, did you read the local rules?
 
Posts: 159 | Location: Texas, USA | Registered: July 11, 2001Reply With QuoteReport This Post
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Yes I have the fish hook hanging out of my mouth Greg. Target? I expect AP will jump right in at any moment and tell me Victoria's Secret has help available for us poor prosecutors and LE personell too.

I'll call the SO in Fort Bend County. Thanks for the info. I will be careful about the expert. Guess the same problem applies to a redacted audio that leaves out all of the driving "dead time" when a CI is meeting for a delivery.
 
Posts: 334 | Location: Beeville, Texas., USA | Registered: September 14, 2001Reply With QuoteReport This Post
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As far as editing audio I'd reccomend Audacity.
www.audacity.sourceforge.net

It's a free program that has an incredible set of audio tools/filters, etc. including an equalizer that can have as many buttons as you want, precisely where you want. It will not export as an MP3 without an additional piece of software. I have a WINK tutorial I developed for the NDAA at the Courtroom Technology seminar two weeks ago that I can send you.

I mentioned the equalizer because that is one of the easiest and most non-invasive methods of "cleaning up" audio. By non-invasive I mean you are not really changing anything, just adjusting the levels of sounds already in the recording. Along this line I'd agree with Bradley to a poin; if you are going to apply sophisticated filters/enhancers and make clear audio out of background noise, you need an expert to discuss what he/she did. However, if you had the original cassette tape and played it on a boombox with an equalizer, there is no prohibition against bumping up or dropping down the treble. With the full version of Realplayer as well as Quicktime and Windows Media Player, you have an equalizer available on your computer to do the same thing. Audacity has a multi-band equalizer, but actually applies the equalizer settings to the audio as an enhancement, not as a playback feature.

If you are actually going to apply filters to an audio recording you should not have a problem if you make clear that the original is available and both the original and enhanced version has been provided to defense counsel so that they had time to formulate objections. The defense needs to object to the accuracy of a specific section, because the predicate that can be laid for the enhanced version is the same as the predicate for the original. If you have an eyewitness to the sounds, they can just as easily testify that the cleaned up version is what it purports to be as the original was, if not moreso. You have a bit of a problem if you are admitting audio from an event that was not personally heard by a witness. The predicate would be the same, but this person cannot say that the tape is accurate, only that the tape is what the equipment recorded. Then you might need an investigator to testify that they muted the 8K frequency and double amplified the 1K band. Again, have your original available and provide both to the defense well ahead of time so that they can make their specific objections at the time the evidence is offered or even prior to trial. The judge can listen to the two recordings and determine whether there is any merit to the defense contention that the cleaned up recording is inaccurate.

This is also the same procedure you would go through to admit an audio that eliminates "dead time." Make you sure you have admitted your original and then make clear you are admitting and publishing a copy of what's already in evidence that will aid the jury in reviewing the evidence. That, or digitize your recording and simply advance it during playback, reading into the record where you are stopping and starting, to the precise point that the good stuff appears.

i can send out more materials on using these programs if anyone needs them.
 
Posts: 42 | Location: Plano, TX | Registered: June 24, 2002Reply With QuoteReport This Post
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Jeff, My email is mwarnerda@yahoo.com. Thanks for the help. You sound like an expert!
 
Posts: 334 | Location: Beeville, Texas., USA | Registered: September 14, 2001Reply With QuoteReport This Post
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