Change datatype volume

How do you change the volume of a sound (MP3 in my case) using the datatype while it is playing?

I have a volume slider, 0-64. I check the value then do this:

IDataTypes->SetDTAttrs(SoundObject,MainWindow,NULL,
SDTA_Volume, SoundVolume,
TAG_DONE);

This works on my X5000 with A-Eon's sound.datatype 53.27, but not with the original 53.6. I tested this on my X5000, WinUAE, and jabirulo's Sam.

@mritter0

Did you restore all the individual datatypes (WAV, mpega etc.) back to the original OS4FE datatypes when you tested with the v53.6 sound.datatype?

No, I did not revert back to the original datatypes. Should that really matter? sound.datatype is what is in control of the output level, not the wav/mpeg.datatype, yes?

@mritter0
Quote:
I'm not sure if it matters. I was just thinking of a reason for the failure. However, I removed the Enhancer datatypes and reverted to the OS4 datatypes for testing. I tested with an AIFF sound file and a WAV sound file. The pause and resume didn't seem to work at all with the OS4 sound datatypes and only one volume change worked. I tried a decrease in volume and a few seconds later an increase in volume. The volume decrease worked but the sound just stopped playing when I increased the volume.

Unless we're both doing something wrong, the prospects for using datatypes to write a sound player with good user control don't look good

@xenic

That's what I was afraid of: seems to have never worked from day 1.

I just wanted some simple controls in Workbench Explorer, not intending to be a full blown player or anything. But nice to have.

STM_PAUSE and STM_RESUME I believe are A-EON options only. I had to STM_STOP with OS4; that works fine, but not ideal.

You would think changing volume would be a common thing and not an old bug/defect in the sound.datatype. No one has wanted to change the volume in the last 5+ years?

@xenic

PM sent.

@mritter0

I removed the pause/resume from my test program and added more volume changes. Here are my results:

aiff.datatype - Sent the termination signal after the first volume change but there were no volume changes.

wav.datatype - The volume changes worked but seemed to be delayed by a second or 2.

8svx.datatype - The first 2 volume changes worked (delayed) and the rest of the volume changes were ignored.

The response to volume changes seems to vary among different sound datatype sub-classes.

@xenic

For the record, the A-Eon implementations all route to the sound.datatype to control volume, the subclasses do very little other than process the data source to pass it up the chain. If you're saying the volume changes don't work on these, let me know.

I cannot vouch for the OS supplied dt classes. I do know that the aiff/8svx didn't interact with the sound data type as expected and had to account for it to "make it work".

@sierratu
O.K. I think the problem mritter0 needs to overcome with Enhancer sound.datatype is pause/play. When play is resumed the sound is garbled. His MP3 player would be fantastic if that problem is fixed.

@sierratu

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