MT Waveform different than SF waveform

[Dave Labrecque]

Bob (or anyone that beats him to it),

I recently restored an archived session to my hard drive. All went well after some serious re-pathing (source files were in several different archives), with one exception: one of the MT region entries shows a bogus waveform when zoomed out (zooming in sees it correctly beyond that "magic zoom point"). The weird thing is that double clicking it into the SF view shows the correct waveform. I tried refreshing, but it didn't help. I looked for read-only attributes being checked for the .wav and .wpd, but they were not.

Any ideas :confused:

It plays back fine in both MT and SF view, BTW.

[Pedro Itriago]

Try deleting the .wpd file so saw creates a new one and see what goes

[Yura]

I just started to say the same that Pedro.
but seniors, please check next:
place the sinus wav on the track.
turn pan slider on it fully left.
build the mix of this sine to next track.
zoom in and out thriugh 256 zoom point.
you see the height of new wav is changes in 2 times !
the one amplitude - the two interpritations of it? what is this?
exactly, the new wav is 6 db smaller than first wav, cause we builded it with only "lefted side". so, we see its wpd gives us wrong interpret. if figure of zoom is more than 128. haw can it be explained?

[Bob L]

Yura,

The wpd files take only the loudest peak information every 256 samples. The current design does not carry positive or negative information, because when zoomed out that far, in general, it is not very visible anyway.

What you are noticing is a waveform peak that is only a negative or positive spike without a corresponding opposite spike. The wpd data is stored as only positive values and when drawn the peak is mirrored on the negative side.

This has not really ever presented any problems, because as you zoom in past the 256 sample mark, you then are actually drawing the real data live from the real wav file.

I have considered changing the structure of the wpd files to include negative data and draw the data to display that, but that will compromise old wpd files and the speed of zoomed out drawings.

I still may do it in a future update, but I still have not made that decision yet.

Bob L

[Bob L]

Dave,

My guess is that clearing the wpd files (as Pedro suggested) for the file in question should solve the problem.

Also, try turning off Peak Data Memory caching in the Options menu and see if that corrects the problem.

Bob L

[Dave Labrecque]

Pedro, Bob...

Well, I just opened it back up to try your suggestions and the waveform is fine. Maybe opening/closing SAW took care of it?

I'm curious: what would deleting the .wpd file have accomplished that doing a refresh did not? Or is it one of those voodoo things? :confused:

[Pedro Itriago]

You would've accomplished the same thing because if saw doesn't find the corresponding .wpd of a wave file, it would had created a new one once the file was accessed by a edl or by being loaded into the mt and/or soundfile view

[Bob L]

Dave,

The problem may have simply been peak data memory caching... the refresh you did may not have also refreshed the cache in memory... I'll look into that.

Closing SAWStudio and re-opening it would have started with a fresh memory cache for the peak data.

Bob L

[Dave Labrecque]

Bob,

For what it's worth, peak data memory caching IS enabled in my default setup (and so was enabled when this happened), so that could be the thing.