Re: what should I understand from kAudioQueueProperty_CurrentLevelMeterDB

2011-05-09 Thread Graham Cox
On 08/05/2011, at 8:28 PM, Niran Bala wrote: How should I interpret this value? When I mute the Mic on my laptop, this value is -120 My GUESS (only) would be that this is the line level, which is logical, since it couldn't possibly be actual sound pressure level, since the signal is

Re: what should I understand from kAudioQueueProperty_CurrentLevelMeterDB

2011-05-09 Thread Wim Lewis
On 8 May 2011, at 11:07 PM, Graham Cox wrote: You need to find in the documentation or ask what 0dB is considered to be in this measurement system. As I understand it, the 0dB reference for a VU meter is usually the maximum volume the system can reproduce without distortion (maybe plus some

Re: what should I understand from kAudioQueueProperty_CurrentLevelMeterDB

2011-05-09 Thread Kyle Sluder
On Sun, May 8, 2011 at 3:28 AM, Niran Bala niran_j...@yahoo.com wrote: Hi, I am trying to measure dB levels of my voice. This has nothing to do with Cocoa. You should instead ask your question on the coreaudio-api list. --Kyle Sluder ___ Cocoa-dev

what should I understand from kAudioQueueProperty_CurrentLevelMeterDB

2011-05-08 Thread Niran Bala
Hi, I am trying to measure dB levels of my voice. I use the following code. UInt32 propertySize = format.mChannelsPerFrame * sizeof (AudioQueueLevelMeterState); AudioQueueGetProperty( queue,