add ability to save samples

src/engine/sample.cpp

@@ -1,4 +1,48 @@
 #include "sample.h"
+#include "../ta-log.h"
+#include <string.h>
+#include <sndfile.h>
+
+const int sampleRates[6]={
+  4000, 8000, 11025, 16000, 22050, 32000
+};
+
+bool DivSample::save(const char* path) {
+  SNDFILE* f;
+  SF_INFO si;
+  memset(&si,0,sizeof(SF_INFO));
+
+  if (length<1) return false;
+
+  si.channels=1;
+  si.samplerate=sampleRates[rate];
+  if (depth==16) {
+    si.format=SF_FORMAT_PCM_16|SF_FORMAT_WAV;
+  } else {
+    si.format=SF_FORMAT_PCM_U8|SF_FORMAT_WAV;
+  }
+
+  f=sf_open(path,SFM_WRITE,&si);
+
+  if (f==NULL) {
+    logE("could not open wave file for saving! %s\n",sf_error_number(sf_error(f)));
+    return false;
+  }
+
+  if (depth==16) {
+    sf_writef_short(f,data,length);
+  } else {
+    short* cbuf=new short[length];
+    for (int i=0; i<length; i++) {
+      cbuf[i]=(data[i]<<8)^0x8000;
+    }
+    sf_writef_short(f,cbuf,length);
+    delete[] cbuf;
+  }
+  sf_close(f);
+
+  return true;
+}
 
 DivSample::~DivSample() {
   if (data) delete[] data;

src/engine/sample.h

@@ -10,6 +10,7 @@ struct DivSample {
   short* rendData;
   unsigned char* adpcmRendData;
 
+  bool save(const char* path);
   DivSample():
     name(""),
     length(0),