4  * The contents of this file are subject to the terms of the
24  * Use is subject to license terms.
51 // u-law max value converted to floating point
54 // XXX - patchable dc time constant:  TC = 1 / (sample rate / DCfreq)
106 		g -= NoSigWeight;  in WeightedGain()
120 // Return latest weighted peak
121 // Clears the weighted peak for next calculation.
127 	// Peak sum is averaged by the cache size  in WeightedPeak()
130 		g -= NoSigWeight;  in WeightedPeak()
172 // Process an input buffer according to the specified flags
185 	if (Undefined(inbuf->GetLength())) {  in Process()
189 		inbuf->RaiseError(err);  in Process()
190 		inbuf->Reference();  in Process()
191 		inbuf->Dereference();  in Process()
195 	// Set up to convert to floating point; verify all header formats  in Process()
196 	newhdr = inbuf->GetHeader();  in Process()
208 	// Convert to floating-point up front, if necessary  in Process()
209 	if (inbuf->GetHeader() != newhdr) {  in Process()
215 	// Reference the resulting buffer to make sure it gets ditched later  in Process()
216 	inbuf->Reference();  in Process()
218 	// run through highpass filter to reject DC  in Process()
227 	inbuf->Dereference();  in Process()
232 // Buffer is assumed to be floating-point double PCM
246 	inhdr = inbuf->GetHeader();  in process_dcfilter()
247 	inptr = (double *)inbuf->GetAddress();  in process_dcfilter()
248 	frames = (size_t)inhdr.Time_to_Samples(inbuf->GetLength());  in process_dcfilter()
252 	// Time constant corresponds to the number of samples for 500Hz  in process_dcfilter()
254 	dcweight = 1. - timeconstant;  in process_dcfilter()
257 	// XXX - should deal with multi-channel data!  in process_dcfilter()
258 	// XXX - for now, check first channel only  in process_dcfilter()
263 		if ((val >= PeakSig) || (val <= -PeakSig)) {  in process_dcfilter()
273 		// Add in this value to weighted average  in process_dcfilter()
275 		val -= DCaverage;  in process_dcfilter()
278 		else if (val < -1.)  in process_dcfilter()
279 			val = -1.;  in process_dcfilter()
285 // Buffer is assumed to be floating-point double PCM
298 	inhdr = inbuf->GetHeader();  in process_instant()
299 	inptr = (double *)inbuf->GetAddress();  in process_instant()
300 	frames = (size_t)inhdr.Time_to_Samples(inbuf->GetLength());  in process_instant()
303 	// XXX - should deal with multi-channel data!  in process_instant()
304 	// XXX - for now, check first channel only  in process_instant()
316 	// Normalize to within a reasonable range  in process_instant()
317 	val -= LoSigInstantRange;  in process_instant()
334 // Buffer is assumed to be floating-point double PCM
347 	inhdr = inbuf->GetHeader();  in process_weighted()
348 	inptr = (double *)inbuf->GetAddress();  in process_weighted()
349 	frames = (size_t)inhdr.Time_to_Samples(inbuf->GetLength());  in process_weighted()
362 	// Scale up the 'no signal' level to avoid a divide in the inner loop  in process_weighted()
367 	//   save the peak sum of squares;  in process_weighted()
370 	// XXX - should deal with multi-channel data!  in process_weighted()
371 	// XXX - for now, check first channel only  in process_weighted()
377 		weighted_sum -= gain_cache[i];  in process_weighted()
378 		gain_cache[i] = val;		// save value to subtract later  in process_weighted()
380 			weighted_peaksum = weighted_sum;	// save peak  in process_weighted()
383 		// above threshold (this attempts to keep the volume  in process_weighted()