* adpcm: added DUCK 4 variant support. (thx M. Melanson who provided me

somes samples.)

modules/codec/adpcm.c

@@ -2,7 +2,7 @@
  * adpcm.c : adpcm variant audio decoder
  *****************************************************************************
  * Copyright (C) 2001, 2002 VideoLAN
- * $Id: adpcm.c,v 1.6 2003/01/13 17:39:05 fenrir Exp $
+ * $Id: adpcm.c,v 1.7 2003/02/16 09:50:22 fenrir Exp $
  *
  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
  *
@@ -41,6 +41,8 @@
 #define ADPCM_IMA_QT    1
 #define ADPCM_IMA_WAV   2
 #define ADPCM_MS        3
+#define ADPCM_DK3       4
+#define ADPCM_DK4       4
 
 typedef struct adec_thread_s
 {
@@ -78,6 +80,7 @@ static void EndThread      ( adec_thread_t * );
 
 static void DecodeAdpcmMs( adec_thread_t *, aout_buffer_t * );
 static void DecodeAdpcmImaWav( adec_thread_t *, aout_buffer_t * );
+static void DecodeAdpcmDk4( adec_thread_t *, aout_buffer_t * );
 
 /*****************************************************************************
  * Module descriptor
@@ -153,7 +156,7 @@ static int OpenDecoder( vlc_object_t *p_this )
 //        case VLC_FOURCC('i','m','a', '4'): /* IMA ADPCM */
         case VLC_FOURCC('m','s',0x00,0x02): /* MS ADPCM */
         case VLC_FOURCC('m','s',0x00,0x11): /* IMA ADPCM */
-//        case VLC_FOURCC('m','s',0x00,0x61): /* Duck DK4 ADPCM */
+        case VLC_FOURCC('m','s',0x00,0x61): /* Duck DK4 ADPCM */
 //        case VLC_FOURCC('m','s',0x00,0x62): /* Duck DK3 ADPCM */
 
             p_fifo->pf_run = RunDecoder;
@@ -242,8 +245,10 @@ static int InitThread( adec_thread_t * p_adec )
             p_adec->i_codec = ADPCM_MS;
             break;
         case VLC_FOURCC('m','s',0x00,0x61): /* Duck DK4 ADPCM */
+            p_adec->i_codec = ADPCM_DK4;
+            break;
         case VLC_FOURCC('m','s',0x00,0x62): /* Duck DK3 ADPCM */
-            p_adec->i_codec = 0;
+            p_adec->i_codec = ADPCM_DK3;
             break;
     }
 
@@ -285,6 +290,11 @@ static int InitThread( adec_thread_t * p_adec )
                 2 * ( p_adec->i_block - 7 * p_adec->p_wf->nChannels ) /
                 p_adec->p_wf->nChannels + 2;
             break;
+        case ADPCM_DK4:
+            p_adec->i_samplesperblock =
+               2 * ( p_adec->i_block - 4 * p_adec->p_wf->nChannels ) /
+               p_adec->p_wf->nChannels + 1;
+            break;
         default:
             p_adec->i_samplesperblock = 0;
     }
@@ -442,6 +452,8 @@ static void DecodeThread( adec_thread_t *p_adec )
             case ADPCM_MS:
                 DecodeAdpcmMs( p_adec, p_aout_buffer );
                 break;
+            case ADPCM_DK4:
+                DecodeAdpcmDk4( p_adec, p_aout_buffer );
             default:
                 break;
         }
@@ -480,6 +492,9 @@ static void EndThread (adec_thread_t *p_adec)
     (v) |= ( *p_buffer ) << 8; p_buffer++; \
     if( (v)&0x8000 ) (v) -= 0x010000;
 
+/*
+ * MS
+ */
 typedef struct adpcm_ms_channel_s
 {
     int i_idelta;
@@ -588,6 +603,9 @@ static void DecodeAdpcmMs( adec_thread_t *p_adec,
 
 }
 
+/*
+ * IMA-WAV
+ */
 typedef struct adpcm_ima_wav_channel_s
 {
     int i_predictor;
@@ -689,6 +707,53 @@ static void DecodeAdpcmImaWav( adec_thread_t *p_adec,
     }
 }
 
+/*
+ * Dk4
+ */
+
+static void DecodeAdpcmDk4( adec_thread_t *p_adec,
+                               aout_buffer_t *p_aout_buffer)
+{
+    uint8_t                 *p_buffer;
+    adpcm_ima_wav_channel_t channel[2];
+    int                     i_nibbles;
+    uint16_t                *p_sample;
+    int                     b_stereo;
+
+    p_buffer = p_adec->p_block;
+    b_stereo = p_adec->p_wf->nChannels == 2 ? 1 : 0;
+
+    GetWord( channel[0].i_predictor );
+    GetByte( channel[0].i_step_index );
+    CLAMP( channel[0].i_step_index, 0, 88 );
+    p_buffer++;
+
+    if( b_stereo )
+    {
+        GetWord( channel[1].i_predictor );
+        GetByte( channel[1].i_step_index );
+        CLAMP( channel[1].i_step_index, 0, 88 );
+        p_buffer++;
+    }
 
+    p_sample = (int16_t*)p_aout_buffer->p_buffer;
 
+    /* first output predictor */
+    *p_sample++ = channel[0].i_predictor;
+    if( b_stereo )
+    {
+        *p_sample++ = channel[1].i_predictor;
+    }
 
+    for( i_nibbles = 0;
+         i_nibbles < p_adec->i_block - 4 * (b_stereo ? 2:1 );
+         i_nibbles++ )
+    {
+        *p_sample++ = AdpcmImaWavExpandNibble( &channel[0],
+                                              (*p_buffer) >> 4);
+        *p_sample++ = AdpcmImaWavExpandNibble( &channel[b_stereo ? 1 : 0],
+                                               (*p_buffer)&0x0f);
+
+        p_buffer++;
+    }
+}