Multimedia API + Delphi

Do you know if it is possible to play a waveform using selective speed, or to play it in reverse direction?
I am using Delphi and MM API.I found the function waveOutGetPlaybackRate but I am not sure for its use. But anyway it asks for the handle of the waveform-audio output device.How do I get that handle if I didn't use the standart waveOutOpen?
I am using instead a Delphi 3.0 MediaPlayer component, which does not return (as far as I know) that handle.
LVL 1
kyriacosAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

chensuCommented:
You can use waveOutSetPlaybackRate to change the playback speed. But not all devices support playback rate changes. To determine whether a device supports playback rate changes, use the WAVECAPS_PLAYBACKRATE flag to test the dwSupport member of the WAVEOUTCAPS structure (filled by the waveOutGetDevCaps function). There is another limited method. Load the wave file into a buffer, change the sample rate of the WAVEFORMAT (e.g., from 11025 to 44100) before using waveOutWrite to play it.

To play a waveform in reverse direction, load the wave file into a buffer, reverse the sample before playing it. There is an example C code called 'reverse' in Windows SDK.

I think you have to use waveOutOpen to get the handle.

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
kyriacosAuthor Commented:
I found the idea of changing sample rates very nice...
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft Development

From novice to tech pro — start learning today.