Re: S12.1U - Audio corruption when exporting WAV audio file on same disk as source DV AVI file

Marc P. — Sat, 03 Jan 2009 01:37:11 GMT

As always we appreciate the heads up Richard. I'll bump this over to QA for testing. Thank you for your efforts.

S12.1U - Audio corruption when exporting WAV audio file on same disk as source DV AVI file

culpanr — Tue, 30 Dec 2008 12:52:27 GMT

Noticed this when exporting the soundtrack from a PAL DV AVI file as a .WAV file (16 bit/stereo/44.1kHz) for processing outside of Studio...happened on the PC in my profile and on an Acer AS5672WLMi notebook PC.

(a) Put entire content of captured std. def. PAL DV tape (DV AVI file) onto the timeline
(b) Went to "make file" - chose "audio" and "PCM 44.1kHz (WAV)" to export just the soundtrack. I chose a folder on the same hard disk drive as the captured video (SATA-II 320-GB, separate from disks with OS and Studio's auxiliary files)

The sound seemingly exported OK, but when played in Windows Media Player or opened with an audio editor was found to be corrupted. The first 2 minutes were OK, then there were lots of skips, gaps and repeated fragments.

I found that:
i. If I exported the sound as .MP3 at 192kbit/sec onto the same disk drive as the source AVI file there was no corruption.
ii. If I exported the sound as PCM (.WAV) onto a different disk drive to the source AVI there was no corruption.

So my gut-feeling is that Studio may have a buffer management problem when exporting the soundtrack - for example if it is trying to read more data at the point that Windows is writing some of the output file to disk (so the disk is busy and the read is blocked) an input buffer may underflow, or if it is trying to write some of the output data and the disk is busy (reading more input data) an output buffer may overflow.

If such a buffer management problem did exist, it might also become apparent even when source AVI and destination .WAV files were on different disks - if the source and target disks are of widely differing speeds (e.g. one internal S-ATA and one external via USB); reading from and processing the audio from the source file might not be able to "keep up" with writing the output or vice versa.

My workaround for now is always to export to a different (internal) drive to the one containing the source AVI file.

Regards,
Richard

Studio - Make Movie

Re: S12.1U - Audio corruption when exporting WAV audio file on same disk as source DV AVI file

S12.1U - Audio corruption when exporting WAV audio file on same disk as source DV AVI file