t2 engine svn checkout

audio/audioCodecGSM.cc

@@ -0,0 +1,195 @@
+//-----------------------------------------------------------------------------
+// V12 Engine
+// 
+// Copyright (c) 2001 GarageGames.Com
+// Portions Copyright (c) 2001 by Sierra Online, Inc.
+//-----------------------------------------------------------------------------
+
+#include <stdio.h>
+
+extern "C" 
+{
+#include "inc/gsm.h"
+}
+#include "audio/audioCodecGSM.h"
+
+// The number of samples encoded at once in the GSM spec
+#define GSM_FRAMESIZE		160
+#define GSM_FRAMESIZE_BYTES	GSM_FRAMESIZE*sizeof(gsm_signal)
+
+//--------------------------------------------------------------------------
+// Class GSMEncoderCodec:
+//--------------------------------------------------------------------------
+GSMEncoderCodec::GSMEncoderCodec()
+{
+}
+
+GSMEncoderCodec::~GSMEncoderCodec()
+{
+   close();
+}
+
+VoiceCodec * GSMEncoderCodec::create(U32 codecId)
+{
+   if(codecId != AUDIO_CODEC_GSM)
+      return(0);
+
+   // create and open the codec
+   GSMEncoderCodec * codec = new GSMEncoderCodec();
+   if(!codec->open())
+   {
+      delete codec;
+      codec = 0;
+   }
+
+   return(codec);
+}
+
+//--------------------------------------------------------------------------
+bool GSMEncoderCodec::open()
+{
+   return true;
+}
+
+void GSMEncoderCodec::close()
+{
+}
+
+//--------------------------------------------------------------------------
+void * GSMEncoderCodec::openStream()
+{
+   return gsm_create();
+}
+
+void GSMEncoderCodec::closeStream(void * stream)
+{
+   if ( stream )
+      gsm_destroy((gsm)stream);
+}
+
+U32 GSMEncoderCodec::process(void * stream, BufferQueue * queue, const U8 * data, U32 maxLen)
+{
+   gsm_frame frame;
+   gsm_signal gsmdata[  GSM_FRAMESIZE];
+   gsm_signal samples[2*GSM_FRAMESIZE];
+   U32 encoded;
+   U8 *output;
+   const U32 framesize = (sizeof frame);
+
+   // Sanity check
+   if ( !stream || !queue ) {
+      return 0;
+   }
+   output = const_cast<U8*>(data);
+   encoded = 0;
+   while ( maxLen >= framesize ) {
+      if ( queue->getUsed() < (sizeof samples) ) {
+         break;
+      }
+      queue->dequeue((U8*)samples, (sizeof samples));
+
+      // Convert the samples to 4000 Hz
+      for ( int i=0, j=0; i<GSM_FRAMESIZE; i += 1, j += 2 ) {
+         gsmdata[i] = ((S32)samples[j]+samples[j+1])/2;
+      }
+      gsm_encode((gsm)stream, gsmdata, frame);
+
+      dMemcpy(output, frame, framesize);
+      encoded += framesize;
+      output += framesize;
+      maxLen -= framesize;
+   }
+   return encoded;
+}
+
+
+//--------------------------------------------------------------------------
+// Class GSMDecoderCodec:
+//--------------------------------------------------------------------------
+GSMDecoderCodec::GSMDecoderCodec()
+{
+}
+
+GSMDecoderCodec::~GSMDecoderCodec()
+{
+   close();
+}
+
+VoiceCodec * GSMDecoderCodec::create(U32 codecId)
+{
+   if(codecId != AUDIO_CODEC_GSM)
+      return(0);
+
+   // create and open the codec
+   GSMDecoderCodec * codec = new GSMDecoderCodec();
+   if(!codec->open())
+   {
+      delete codec;
+      codec = 0;
+   }
+
+   return(codec);
+}
+
+//--------------------------------------------------------------------------
+bool GSMDecoderCodec::open()
+{
+   return(true);
+}
+
+void GSMDecoderCodec::close()
+{
+}
+
+//--------------------------------------------------------------------------
+void * GSMDecoderCodec::openStream()
+{
+   return gsm_create();
+}
+
+void GSMDecoderCodec::closeStream(void * stream)
+{
+   if ( stream )
+      gsm_destroy((gsm)stream);
+}
+
+U32 GSMDecoderCodec::process(void * stream, BufferQueue * queue, const U8 * data, U32 maxLen)
+{
+   gsm_frame frame;
+   gsm_signal gsmdata[GSM_FRAMESIZE];
+   U32 decoded;
+   U8 *output;
+   const U32 framesize = 2*GSM_FRAMESIZE_BYTES;
+
+   // Sanity check
+   if ( !stream || !queue ) {
+      return 0;
+   }
+   output = const_cast<U8*>(data);
+   decoded = 0;
+   while ( maxLen >= framesize ) {
+      gsm_signal *samples = (gsm_signal *)output;
+
+      // Decode another frame of data
+      if ( queue->getUsed() < (sizeof frame) ) {
+         break;
+      }
+      queue->dequeue((U8*)frame, (sizeof frame));
+
+      gsm_decode((gsm)stream, frame, gsmdata);
+
+      // Convert the samples from 4000 Hz
+      for ( int i=0, j=0; i<GSM_FRAMESIZE; i += 1, j += 2 ) {
+         samples[j] = gsmdata[i];
+         if ( i == (GSM_FRAMESIZE-1) ) {
+            samples[j+1] = gsmdata[i];
+         } else {
+            samples[j+1] = ((S32)gsmdata[i]+gsmdata[i+1])/2;
+         }
+      }
+      decoded += framesize;
+      output += framesize;
+      maxLen -= framesize;
+   }
+   return decoded;
+}