GH1 does not have ALC

I can tell you this.
Panasonic can make your AGC level selection (they already have same menu for volume, so simple copy-paste), meters (small routine) and level adjustment routines (even smalle routine) in few days using one developer. I am serious here.
Problem here is that feedback system is broken with all this Japan corporations.
 
at least we have you Vitaly ! you did what the japanese corporation would have never done ...
If we ever get someone from the Lumix developer dept. to look, listen and react, it will also be thanks to your work! we can only try and hope....
 
musicsmith said:
The GH1 uses Dolby Digital Stereo Creator. All .ac3 audio must have Dolby encoding, including AVCHD. The Dynamic Range Control is based on a few settings, some controllable with the right hardware/software.

The stills attached are taken from page 88 of the Dolby Encoding Guidelines, you can read it at the link below.

http://www.dolby.com/uploadedFiles/...PDFs/Professional/46_DDEncodingGuidelines.pdf
Click to expand...
The document linked above refers to the Dolby Digital Professional Encoder. The Dolby Digital Stereo Creator (used by the GH1/GF1 in AVCHD modes only) is based on the Dolby Digital Consumer Encoder, which implements a limited subset of the options available in the Professional Encoder. Each licensee of Dolby Digital software has the option of implementing any certified subset of the Dolby Digital specifications documented by the ATSC. All implementations are tested for compliance with published specifications before commercial release.

One important point to note is that the AGC compression algorithm used in Dolby Digital encoders is performed entirely in software as an integral part of Dolby AC-3 encoding. Metadata is encoded along with the AGC compression that enables any Dolby Digital decoder to optionally restore the original dynamic range of the compressed recording to any desired degree of realism. A number of consumer surround sound receivers provide user control of the dynamic range of Dolby Digital playback.

The audio input paths of the GH1 and GF1 are shared by both the AVCHD Dolby Digital encoder and the MJPEG linear PCM encoder. Since these circuits were designed and implemented by Panasonic using a combination of analog and digital components, additional AGC processing may very well be applied to the audio signal before it is converted to AC-3 or PCM encoding.
 
I have small question to lpowell.

I see few strings about "reusing exponents in block" , "dpfe" and "pacmants" (packed mantissa, I suppose).
Is it part of Dolby ancoder?
 
I do not mean documentation, but rather source code implementation :-).
Even in standard I see exponents, mantissa and quanitization used heavily.
And this parts is not AVCHD, so it must be AC3 :-)
 
Almost all Panasonic consumer and prosumer products have insanely high audio input sensitivity, around -70dBV nominal and -40dBV clipping. I had a camcorder, AG-DVC-30 which Panasonic labelled as "professional", had the same insane audio input sensitivity.

Panasonic's assumption must be that most people use dynamic mics, which typically have sub 1mV output level.
 
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