msacm32: Added converter for ADPCM to PCM 8 bit mono.

dlls/imaadp32.acm/imaadp32.c

@@ -179,6 +179,25 @@ static inline void  W16(unsigned char* dst, short s)
     dst[1] = HIBYTE(s);
 }
 
+/***********************************************************************
+ *           W8
+ *
+ * Write a 8 bit sample
+ */
+static inline void W8(unsigned char* dst, short s)
+{
+    dst[0] = (unsigned char)((s + 32768) >> 8);
+}
+
+
+static inline void W8_16(unsigned char* dst, short s, int bytes)
+{
+    if(bytes == 1)
+        W8(dst, s);
+    else
+        W16(dst, s);
+}
+
 /* IMA (or DVI) APDCM codec routines */
 
 static const unsigned IMA_StepTable[89] =
@@ -339,7 +358,7 @@ static	void cvtSSima16K(PACMDRVSTREAMINSTANCE adsi,
     }
 }
 
-static	void cvtMMima16K(PACMDRVSTREAMINSTANCE adsi,
+static void cvtMMimaK(PACMDRVSTREAMINSTANCE adsi,
                     const unsigned char* src, LPDWORD nsrc,
                     unsigned char* dst, LPDWORD ndst)
 {
@@ -347,15 +366,15 @@ static	void cvtMMima16K(PACMDRVSTREAMINSTANCE adsi,
     int stepIndex;
     int nsamp_blk = ((LPIMAADPCMWAVEFORMAT)adsi->pwfxSrc)->wSamplesPerBlock;
     int nsamp;
+    int bytesPerSample = adsi->pwfxDst->wBitsPerSample / 8;
     /* compute the number of entire blocks we can decode...
      * it's the min of the number of entire blocks in source buffer and the number
      * of entire blocks in destination buffer
      */
-    DWORD	nblock = min(*nsrc / adsi->pwfxSrc->nBlockAlign,
-                             *ndst / (nsamp_blk * 2));
+    DWORD nblock = min(*nsrc / adsi->pwfxSrc->nBlockAlign, *ndst / (nsamp_blk * bytesPerSample));
 
     *nsrc = nblock * adsi->pwfxSrc->nBlockAlign;
-    *ndst = nblock * nsamp_blk * 2;
+    *ndst = nblock * nsamp_blk * bytesPerSample;
 
     nsamp_blk--; /* remove the sample in block header */
     for (; nblock > 0; nblock--)
@@ -367,14 +386,14 @@ static	void cvtMMima16K(PACMDRVSTREAMINSTANCE adsi,
         stepIndex = (unsigned)*(src + 2);
         clamp_step_index(&stepIndex);
         src += 4;
-	W16(dst, sample);	dst += 2;
+        W8_16(dst, sample, bytesPerSample); dst += bytesPerSample;
 
         for (nsamp = nsamp_blk; nsamp > 0; nsamp -= 2)
         {
             process_nibble(*src, &stepIndex, &sample);
-	    W16(dst, sample); dst += 2;
+            W8_16(dst, sample, bytesPerSample); dst += bytesPerSample;
             process_nibble(*src++ >> 4, &stepIndex, &sample);
-	    W16(dst, sample); dst += 2;
+            W8_16(dst, sample, bytesPerSample); dst += bytesPerSample;
         }
         /* we have now to realign the source pointer on block */
         src = in_src + adsi->pwfxSrc->nBlockAlign;
@@ -735,10 +754,11 @@ static	LRESULT	ADPCM_StreamOpen(PACMDRVSTREAMINSTANCE adsi)
     {
         /* resampling or mono <=> stereo not available
          * ADPCM algo only define 16 bit per sample output
+         * (The API seems to still allow 8 bit per sample output)
          */
         if (adsi->pwfxSrc->nSamplesPerSec != adsi->pwfxDst->nSamplesPerSec ||
             adsi->pwfxSrc->nChannels != adsi->pwfxDst->nChannels ||
-            adsi->pwfxDst->wBitsPerSample != 16)
+            (adsi->pwfxDst->wBitsPerSample != 16 && adsi->pwfxDst->wBitsPerSample != 8))
             goto theEnd;
 
         nspb = ((LPIMAADPCMWAVEFORMAT)adsi->pwfxSrc)->wSamplesPerBlock;
@@ -756,7 +776,12 @@ static	LRESULT	ADPCM_StreamOpen(PACMDRVSTREAMINSTANCE adsi)
         if (adsi->pwfxDst->wBitsPerSample == 16 && adsi->pwfxDst->nChannels == 2)
             aad->convert = cvtSSima16K;
         if (adsi->pwfxDst->wBitsPerSample == 16 && adsi->pwfxDst->nChannels == 1)
-	    aad->convert = cvtMMima16K;
+            aad->convert = cvtMMimaK;
+        if (adsi->pwfxDst->wBitsPerSample == 8 && adsi->pwfxDst->nChannels == 1)
+            aad->convert = cvtMMimaK;
+        /* FIXME: Stereo support for 8bit samples*/
+        if (adsi->pwfxDst->wBitsPerSample == 8 && adsi->pwfxDst->nChannels == 2)
+            goto theEnd;
     }
     else if (adsi->pwfxSrc->wFormatTag == WAVE_FORMAT_PCM &&
              adsi->pwfxDst->wFormatTag == WAVE_FORMAT_IMA_ADPCM)