iriver: proper wav file handling by Frederic Devernay (patch #1245261). Adapted the metadata part to the new metadata.c, and did a few minor changes in the codec. Some of the file format checks in the codec should IMHO be moved to metadata.c, but I left that for later.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7542 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 646 insertions, 62 deletions

diff --git a/apps/codecs/wav.c b/apps/codecs/wav.c
index d2ae7bd6c3..36076caf25 100644
--- a/apps/codecs/wav.c
+++ b/apps/codecs/wav.c
@@ -21,11 +21,75 @@
 #include "playback.h"
 #include "lib/codeclib.h"
 #include "dsp.h"
+#include "inttypes.h"
 
-#define BYTESWAP(x) (((x>>8) & 0xff) | ((x<<8) & 0xff00))
+/* This codec support WAVE files with the following formats:
+ * - PCM, up to 32 bits, supporting 32 bits playback when useful.
+ * - ALAW and MULAW (16 bits compressed on 8 bits).
+ * - DVI_ADPCM (16 bits compressed on 4 bits).
+ * 
+ *  For a good documentation on WAVE files, see:
+ *  http://www.tsp.ece.mcgill.ca/MMSP/Documents/AudioFormats/WAVE/WAVE.html
+ *  and
+ *  http://www.sonicspot.com/guide/wavefiles.html
+ *
+ *  For sample WAV files, see:
+ *  http://www.tsp.ece.mcgill.ca/MMSP/Documents/AudioFormats/WAVE/Samples.html
+ *
+ * The most common formats seem to be PCM, ADPCM, DVI_ADPCM, IEEE_FLOAT,
+ *  ALAW and MULAW
+ */
+
+/* These constants are from RFC 2361. */
+enum
+{
+    WAVE_FORMAT_UNKNOWN = 0x0000, /* Microsoft Unknown Wave Format */
+    WAVE_FORMAT_PCM = 0x0001,   /* Microsoft PCM Format */
+    WAVE_FORMAT_ADPCM = 0x0002, /* Microsoft ADPCM Format */
+    WAVE_FORMAT_IEEE_FLOAT = 0x0003, /* IEEE Float */
+    WAVE_FORMAT_VSELP = 0x0004, /* Compaq Computer's VSELP */
+    WAVE_FORMAT_IBM_CVSD = 0x0005, /* IBM CVSD */
+    WAVE_FORMAT_ALAW = 0x0006,  /* Microsoft ALAW */
+    WAVE_FORMAT_MULAW = 0x0007, /* Microsoft MULAW */
+    WAVE_FORMAT_OKI_ADPCM = 0x0010, /* OKI ADPCM */
+    WAVE_FORMAT_DVI_ADPCM = 0x0011, /* Intel's DVI ADPCM */
+    WAVE_FORMAT_MEDIASPACE_ADPCM = 0x0012, /* Videologic's MediaSpace ADPCM */
+    WAVE_FORMAT_SIERRA_ADPCM = 0x0013, /* Sierra ADPCM */
+    WAVE_FORMAT_G723_ADPCM = 0x0014, /* G.723 ADPCM */
+    WAVE_FORMAT_DIGISTD = 0x0015, /* DSP Solutions' DIGISTD */
+    WAVE_FORMAT_DIGIFIX = 0x0016, /* DSP Solutions' DIGIFIX */
+    WAVE_FORMAT_DIALOGIC_OKI_ADPCM = 0x0017, /* Dialogic OKI ADPCM */
+    WAVE_FORMAT_MEDIAVISION_ADPCM = 0x0018, /* MediaVision ADPCM */
+    WAVE_FORMAT_CU_CODEC = 0x0019, /* HP CU */
+    WAVE_FORMAT_YAMAHA_ADPCM = 0x0020, /* Yamaha ADPCM */
+    WAVE_FORMAT_SONARC = 0x0021, /* Speech Compression's Sonarc */
+    WAVE_FORMAT_DSP_TRUESPEECH = 0x0022, /* DSP Group's True Speech */
+    WAVE_FORMAT_ECHOSC1 = 0x0023, /* Echo Speech's EchoSC1 */
+    WAVE_FORMAT_AUDIOFILE_AF36 = 0x0024, /* Audiofile AF36 */
+    WAVE_FORMAT_APTX = 0x0025,  /* APTX */
+    WAVE_FORMAT_DOLBY_AC2 = 0x0030, /* Dolby AC2 */
+    WAVE_FORMAT_GSM610 = 0x0031, /* GSM610 */
+    WAVE_FORMAT_MSNAUDIO = 0x0032, /* MSNAudio */
+    WAVE_FORMAT_ANTEX_ADPCME = 0x0033, /* Antex ADPCME */
+
+    WAVE_FORMAT_MPEG = 0x0050,  /* MPEG */
+    WAVE_FORMAT_MPEGLAYER3 = 0x0055, /* MPEG layer 3 */
+    WAVE_FORMAT_LUCENT_G723 = 0x0059, /* Lucent G.723 */
+    WAVE_FORMAT_G726_ADPCM = 0x0064, /* G.726 ADPCM */
+    WAVE_FORMAT_G722_ADPCM = 0x0065, /* G.722 ADPCM */
 
-/* Number of bytes to process in one iteration */
-#define WAV_CHUNK_SIZE (1024*4)
+    IBM_FORMAT_MULAW = 0x0101,  /* same as WAVE_FORMAT_MULAW */
+    IBM_FORMAT_ALAW = 0x0102,   /* same as WAVE_FORMAT_ALAW */
+    IBM_FORMAT_ADPCM = 0x0103,
+
+    WAVE_FORMAT_CREATIVE_ADPCM = 0x0200,
+
+    WAVE_FORMAT_EXTENSIBLE = 0xFFFE
+};
+
+/* Maximum number of bytes to process in one iteration */
+/* for 44.1kHz stereo 16bits, this represents 0.023s ~= 1/50s */
+#define WAV_CHUNK_SIZE (1024*2)
 
 #ifndef SIMULATOR
 extern char iramcopy[];
@@ -33,37 +97,149 @@ extern char iramstart[];
 extern char iramend[];
 #endif
 
+/* Those are lookup tables, so they should be in the idata section
+ * (fast but small RAM on the coldfire processor) */
+static int16_t alaw2linear16[256] IDATA_ATTR = {
+     -5504,   -5248,   -6016,   -5760,   -4480,   -4224,   -4992,
+     -4736,   -7552,   -7296,   -8064,   -7808,   -6528,   -6272,
+     -7040,   -6784,   -2752,   -2624,   -3008,   -2880,   -2240,
+     -2112,   -2496,   -2368,   -3776,   -3648,   -4032,   -3904,
+     -3264,   -3136,   -3520,   -3392,  -22016,  -20992,  -24064,
+    -23040,  -17920,  -16896,  -19968,  -18944,  -30208,  -29184,
+    -32256,  -31232,  -26112,  -25088,  -28160,  -27136,  -11008,
+    -10496,  -12032,  -11520,   -8960,   -8448,   -9984,   -9472,
+    -15104,  -14592,  -16128,  -15616,  -13056,  -12544,  -14080,
+    -13568,    -344,    -328,    -376,    -360,    -280,    -264,
+      -312,    -296,    -472,    -456,    -504,    -488,    -408,
+      -392,    -440,    -424,     -88,     -72,    -120,    -104,
+       -24,      -8,     -56,     -40,    -216,    -200,    -248,
+      -232,    -152,    -136,    -184,    -168,   -1376,   -1312,
+     -1504,   -1440,   -1120,   -1056,   -1248,   -1184,   -1888,
+     -1824,   -2016,   -1952,   -1632,   -1568,   -1760,   -1696,
+      -688,    -656,    -752,    -720,    -560,    -528,    -624,
+      -592,    -944,    -912,   -1008,    -976,    -816,    -784,
+      -880,    -848,    5504,    5248,    6016,    5760,    4480,
+      4224,    4992,    4736,    7552,    7296,    8064,    7808,
+      6528,    6272,    7040,    6784,    2752,    2624,    3008,
+      2880,    2240,    2112,    2496,    2368,    3776,    3648,
+      4032,    3904,    3264,    3136,    3520,    3392,   22016,
+     20992,   24064,   23040,   17920,   16896,   19968,   18944,
+     30208,   29184,   32256,   31232,   26112,   25088,   28160,
+     27136,   11008,   10496,   12032,   11520,    8960,    8448,
+      9984,    9472,   15104,   14592,   16128,   15616,   13056,
+     12544,   14080,   13568,     344,     328,     376,     360,
+       280,     264,     312,     296,     472,     456,     504,
+       488,     408,     392,     440,     424,      88,      72,
+       120,     104,      24,       8,      56,      40,     216,
+       200,     248,     232,     152,     136,     184,     168,
+      1376,    1312,    1504,    1440,    1120,    1056,    1248,
+      1184,    1888,    1824,    2016,    1952,    1632,    1568,
+      1760,    1696,     688,     656,     752,     720,     560,
+       528,     624,     592,     944,     912,    1008,     976,
+       816,     784,     880,     848
+};
+
+static int16_t ulaw2linear16[256] IDATA_ATTR = {
+    -32124,  -31100,  -30076,  -29052,  -28028,  -27004,  -25980,
+    -24956,  -23932,  -22908,  -21884,  -20860,  -19836,  -18812,
+    -17788,  -16764,  -15996,  -15484,  -14972,  -14460,  -13948,
+    -13436,  -12924,  -12412,  -11900,  -11388,  -10876,  -10364,
+     -9852,   -9340,   -8828,   -8316,   -7932,   -7676,   -7420,
+     -7164,   -6908,   -6652,   -6396,   -6140,   -5884,   -5628,
+     -5372,   -5116,   -4860,   -4604,   -4348,   -4092,   -3900,
+     -3772,   -3644,   -3516,   -3388,   -3260,   -3132,   -3004,
+     -2876,   -2748,   -2620,   -2492,   -2364,   -2236,   -2108,
+     -1980,   -1884,   -1820,   -1756,   -1692,   -1628,   -1564,
+     -1500,   -1436,   -1372,   -1308,   -1244,   -1180,   -1116,
+     -1052,    -988,    -924,    -876,    -844,    -812,    -780,
+      -748,    -716,    -684,    -652,    -620,    -588,    -556,
+      -524,    -492,    -460,    -428,    -396,    -372,    -356,
+      -340,    -324,    -308,    -292,    -276,    -260,    -244,
+      -228,    -212,    -196,    -180,    -164,    -148,    -132,
+      -120,    -112,    -104,     -96,     -88,     -80,     -72,
+       -64,     -56,     -48,     -40,     -32,     -24,     -16,
+        -8,       0,   32124,   31100,   30076,   29052,   28028,
+     27004,   25980,   24956,   23932,   22908,   21884,   20860,
+     19836,   18812,   17788,   16764,   15996,   15484,   14972,
+     14460,   13948,   13436,   12924,   12412,   11900,   11388,
+     10876,   10364,    9852,    9340,    8828,    8316,    7932,
+      7676,    7420,    7164,    6908,    6652,    6396,    6140,
+      5884,    5628,    5372,    5116,    4860,    4604,    4348,
+      4092,    3900,    3772,    3644,    3516,    3388,    3260,
+      3132,    3004,    2876,    2748,    2620,    2492,    2364,
+      2236,    2108,    1980,    1884,    1820,    1756,    1692,
+      1628,    1564,    1500,    1436,    1372,    1308,    1244,
+      1180,    1116,    1052,     988,     924,     876,     844,
+       812,     780,     748,     716,     684,     652,     620,
+       588,     556,     524,     492,     460,     428,     396,
+       372,     356,     340,     324,     308,     292,     276,
+       260,     244,     228,     212,     196,     180,     164,
+       148,     132,     120,     112,     104,      96,      88,
+        80,      72,      64,      56,      48,      40,      32,
+        24,      16,       8,       0
+};
+
+static uint16_t dvi_adpcm_steptab[ 89 ] IDATA_ATTR = {
+    7, 8, 9, 10, 11, 12, 13, 14,
+    16, 17, 19, 21, 23, 25, 28, 31,
+    34, 37, 41, 45, 50, 55, 60, 66,
+    73, 80, 88, 97, 107, 118, 130, 143,
+    157, 173, 190, 209, 230, 253, 279, 307,
+    337, 371, 408, 449, 494, 544, 598, 658,
+    724, 796, 876, 963, 1060, 1166, 1282, 1411,
+    1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
+    3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
+    7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
+    15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
+    32767 };
+static int dvi_adpcm_indextab4[ 8 ] IDATA_ATTR = { -1, -1, -1, -1, 2, 4, 6, 8 };
+static int dvi_adpcm_indextab3[ 4 ] IDATA_ATTR = { -1, -1, 1, 2 };
+
+static int16_t int16_samples[WAV_CHUNK_SIZE] IDATA_ATTR;
+
+static enum codec_status
+decode_dvi_adpcm(struct codec_api* rb,
+                 const uint8_t *buf,
+                 int n,
+                 uint16_t channels, uint16_t bitspersample,
+                 int16_t *pcmout,
+                 size_t *pcmoutsize);
+
 /* this is the codec entry point */
 enum codec_status codec_start(struct codec_api* api)
 {
-    struct codec_api* rb = api;
-    struct codec_api* ci = api;
-  unsigned long samplerate,numbytes,totalsamples,samplesdone,nsamples;
-  int channels,bytespersample,bitspersample;
-  unsigned int i;
-  size_t n;
+  struct codec_api* rb = api;
+  uint32_t numbytes, bytesdone;
+  uint32_t totalsamples = 0;
+  uint16_t channels=0;
+  uint16_t samplesperblock = 0;
+  int bytespersample=0;
+  uint16_t bitspersample;
+  uint32_t i;
+  size_t n, wavbufsize;
   int endofstream;
-  unsigned char* header;
-  unsigned short* wavbuf;
+  unsigned char* buf;
+  uint16_t* wavbuf;
+  long chunksize;
+  uint16_t formattag = 0;
+  uint16_t blockalign = 0;
+  uint32_t avgbytespersec = 0;
+  off_t firstblockposn;         /* position of the first block in file */
+  int shortorlong = 1;          /* do we output shorts (1) or longs (2)? */
+  int32_t * const int32_samples = (int32_t*)int16_samples;
 
   /* Generic codec initialisation */
   TEST_CODEC_API(api);
 
-  /* if you are using a global api pointer, don't forget to copy it!
-     otherwise you will get lovely "I04: IllInstr" errors... :-) */
-  rb = api;
-
 #ifndef SIMULATOR
   rb->memcpy(iramstart, iramcopy, iramend-iramstart);
 #endif
 
-  ci->configure(CODEC_SET_FILEBUF_LIMIT, (int *)(1024*1024*10));
-  ci->configure(CODEC_SET_FILEBUF_WATERMARK, (int *)(1024*512));
-  ci->configure(CODEC_SET_FILEBUF_CHUNKSIZE, (int *)(1024*256));
+  rb->configure(CODEC_SET_FILEBUF_LIMIT, (int *)(1024*1024*10));
+  rb->configure(CODEC_SET_FILEBUF_WATERMARK, (int *)(1024*512));
+  rb->configure(CODEC_SET_FILEBUF_CHUNKSIZE, (int *)(1024*256));
 
-  ci->configure(DSP_DITHER, (bool *)false);
-  ci->configure(DSP_SET_STEREO_MODE, (int *)STEREO_INTERLEAVED);
-  ci->configure(DSP_SET_SAMPLE_DEPTH, (int *)(16));
+  rb->configure(DSP_DITHER, (bool *)false);
   
   next_track:
 
@@ -73,76 +249,484 @@ enum codec_status codec_start(struct codec_api* api)
 
   while (!*rb->taginfo_ready)
       rb->yield();
-
-  /* Always enable DSP to support voice ui. */
-  rb->configure(CODEC_DSP_ENABLE, (bool *)true);
-  rb->configure(DSP_SET_FREQUENCY, (long *)(rb->id3->frequency));
     
-  /* FIX: Correctly parse WAV header - we assume canonical 44-byte header */
-
-  header=ci->request_buffer(&n,44);
-  if (n!=44) {
+  /* assume the WAV header is less than 1024 bytes */
+  buf=rb->request_buffer(&n,1024);
+  if (n<44) {
     return CODEC_ERROR;
   }
-  if ((memcmp(header,"RIFF",4)!=0) || (memcmp(&header[8],"WAVEfmt",7)!=0)) {
+  if ((memcmp(buf,"RIFF",4)!=0) || (memcmp(&buf[8],"WAVE",4)!=0)) {
     return CODEC_ERROR;
   }
 
-  samplerate=header[24]|(header[25]<<8)|(header[26]<<16)|(header[27]<<24);
-  bitspersample=header[34];
-  channels=header[22];
-  bytespersample=((bitspersample/8)*channels);
-  numbytes=(header[40]|(header[41]<<8)|(header[42]<<16)|(header[43]<<24));
-  totalsamples=numbytes/bytespersample;
+  buf += 12;
+  n -= 12;
+  bitspersample = 0;
+  numbytes = 0;
+  totalsamples = 0;
+  /* read until the data chunk, which should be last */
+  while(numbytes == 0 && n >= 8) {
+      /* chunkSize */
+      i = (buf[4]|(buf[5]<<8)|(buf[6]<<16)|(buf[7]<<24));
+      if (memcmp(buf,"fmt ",4)==0) {
+          if (i<16) {
+              DEBUGF("CODEC_ERROR: 'fmt ' chunk size=%lu < 16\n",i);
+              return CODEC_ERROR;
+          }
+          /* wFormatTag */
+          formattag=buf[8]|(buf[9]<<8);
+          /* wChannels */
+          channels=buf[10]|(buf[11]<<8);
+          /* skipping dwSamplesPerSec */
+          /* dwAvgBytesPerSec */
+          avgbytespersec = buf[16]|(buf[17]<<8)|(buf[18]<<16)|(buf[19]<<24);
+          /* wBlockAlign */
+          blockalign=buf[20]|(buf[21]<<8);
+          /* wBitsPerSample */
+          bitspersample=buf[22]|(buf[23]<<8);
+          if (formattag != WAVE_FORMAT_PCM) {
+              uint16_t size;
+              if (i<18) {
+                  /* this is not a fatal error with some formats,
+                   * we'll see later if we can't decode it */
+                  DEBUGF("CODEC_WARNING: non-PCM WAVE (formattag=0x%x) "
+                         "doesn't have ext. fmt descr (chunksize=%d<18).\n",
+                         formattag, i);
+              }
+              size = buf[24]|(buf[25]<<8);
+              if (formattag == WAVE_FORMAT_DVI_ADPCM) {
+                  if (size < 2) {
+                      DEBUGF("CODEC_ERROR: dvi_adpcm is missing "
+                             "SamplesPerBlock value\n");
+                      return CODEC_ERROR;
+                  }
+                  samplesperblock = buf[26]|(buf[27]<<8);
+              }
+              else if (formattag == WAVE_FORMAT_EXTENSIBLE) {
+                  if (size < 22) {
+                      DEBUGF("CODEC_ERROR: WAVE_FORMAT_EXTENSIBLE is "
+                             "missing extension\n");
+                      return CODEC_ERROR;
+                  }
+                  /* wValidBitsPerSample */
+                  bitspersample = buf[26]|(buf[27]<<8);
+                  /* skipping dwChannelMask (4bytes) */
+                  /* SubFormat (only get the first two bytes) */
+                  formattag = buf[32]|(buf[33]<<8);
+              }
+          }
+      }
+      else if (memcmp(buf,"data",4)==0) {
+          numbytes=i;
+          i=0; /* advance to the beginning of data */
+      }
+      else if (memcmp(buf,"fact",4)==0) {
+          /* dwSampleLength */
+          if (i>=4) {
+              totalsamples = (buf[8]|(buf[9]<<8)|(buf[10]<<16)|(buf[11]<<24));
+          }
+      }
+      else {
+          DEBUGF("unknown WAVE chunk: '%c%c%c%c', size=%lu\n",
+                 buf[0], buf[1], buf[2], buf[3],i);
+      }
+      /* go to next chunk (even chunk sizes must be padded) */
+      if (i & 0x01)
+          i++;
+      buf += i+8;
+      if (n < (i+8)) {
+          DEBUGF("CODEC_ERROR: WAVE header size > 1024\n");
+          return CODEC_ERROR;
+      }
+      n -= i+8;
+  }
 
-  if ((bitspersample!=16) || (channels != 2)) {
-    return CODEC_ERROR;
+  if (channels == 0) {
+      DEBUGF("CODEC_ERROR: 'fmt ' chunk not found or 0-channels file\n");
+      return CODEC_ERROR;
+  }
+  if (numbytes == 0) {
+      DEBUGF("CODEC_ERROR: 'data' chunk not found or has zero-length\n");
+      return CODEC_ERROR;
+  }
+  if (formattag != WAVE_FORMAT_PCM && totalsamples == 0) {
+      /* This is non-fatal for some formats */
+      DEBUGF("CODEC_WARNING: non-PCM WAVE doesn't have a 'fact' chunk\n");
+  }
+  if (formattag == WAVE_FORMAT_ALAW || formattag == WAVE_FORMAT_MULAW ||
+      formattag == IBM_FORMAT_ALAW || formattag == IBM_FORMAT_MULAW) {
+      if (bitspersample != 8) {
+          DEBUGF("CODEC_ERROR: alaw and mulaw must have 8 bitspersample\n");
+          return CODEC_ERROR;
+      }
+      bytespersample = channels;
+  }
+  if ( formattag == WAVE_FORMAT_DVI_ADPCM
+       && bitspersample != 4 && bitspersample != 3) {
+      DEBUGF("CODEC_ERROR: dvi_adpcm must have 3 or 4 bitspersample\n");
+      return CODEC_ERROR;
+  }
+  if (formattag == WAVE_FORMAT_PCM && bitspersample > 32) {
+      DEBUGF("CODEC_ERROR: pcm with more than 32 bitspersample "
+             "is unsupported\n");
+      return CODEC_ERROR;
+  }
+
+  rb->configure(CODEC_DSP_ENABLE, (bool *)true);
+  rb->configure(DSP_SET_FREQUENCY, (long *)(rb->id3->frequency));
+
+  if (bitspersample <= 16) {
+      rb->configure(DSP_SET_SAMPLE_DEPTH, (int *)(16));
+  } else {
+      shortorlong = 2;
+      rb->configure(DSP_DITHER, (bool *)false);
+      rb->configure(DSP_SET_SAMPLE_DEPTH, (long *) (32));
+      rb->configure(DSP_SET_CLIP_MAX, (long *) (2147483647));
+      rb->configure(DSP_SET_CLIP_MIN, (long *) (-2147483647-1));
+  }
+
+  if (channels == 2) {
+      rb->configure(DSP_SET_STEREO_MODE, (int *)STEREO_INTERLEAVED);
+  } else if (channels == 1) {
+      rb->configure(DSP_SET_STEREO_MODE, (int *)STEREO_MONO);
+  } else {
+      DEBUGF("CODEC_ERROR: more than 2 channels\n");
+      return CODEC_ERROR;
+  }
+
+  if (totalsamples == 0) {
+      if (formattag == WAVE_FORMAT_PCM ||
+          formattag == WAVE_FORMAT_ALAW || formattag == WAVE_FORMAT_MULAW ||
+          formattag == IBM_FORMAT_ALAW || formattag == IBM_FORMAT_MULAW) {
+          /* for PCM and derived formats only */
+          bytespersample=(((bitspersample-1)/8+1)*channels);
+          totalsamples=numbytes/bytespersample;
+      }
+      else {
+          DEBUGF("CODEC_ERROR: cannot compute totalsamples\n");
+          return CODEC_ERROR;
+      }
   }
 
-  ci->advance_buffer(44);
+  firstblockposn = (1024-n);
+  rb->advance_buffer(firstblockposn);
 
   /* The main decoder loop */
 
-  samplesdone=0;
-  ci->set_elapsed(0);
+  bytesdone=0;
+  rb->set_elapsed(0);
   endofstream=0;
+  /* chunksize is computed so that one chunk is about 1/50s.
+   * this make 4096 for 44.1kHz 16bits stereo.
+   * It also has to be a multiple of blockalign */
+  chunksize = (1 + avgbytespersec / (50*blockalign)) * blockalign;
+  /* check that the output buffer is big enough (convert to samplespersec,
+     then round to the blockalign multiple below) */
+  if (((uint64_t)chunksize*rb->id3->frequency*channels*shortorlong)
+      / (uint64_t)avgbytespersec >= WAV_CHUNK_SIZE) {
+      chunksize = ((uint64_t)WAV_CHUNK_SIZE * avgbytespersec
+                   / ((uint64_t)rb->id3->frequency * channels * shortorlong 
+                      * blockalign)) * blockalign;
+  }
+
   while (!endofstream) {
-    if (ci->stop_codec || ci->reload_codec) {
+      uint8_t *wavbuf8;
+
+      rb->yield();
+    if (rb->stop_codec || rb->reload_codec) {
       break;
     }
 
-    wavbuf=ci->request_buffer(&n,WAV_CHUNK_SIZE);
+    if (rb->seek_time) {
+        uint32_t newpos;
 
-    if (n==0) break; /* End of stream */
+        /* use avgbytespersec to round to the closest blockalign multiple,
+           add firstblockposn. 64-bit casts to avoid overflows. */
+        newpos = (((uint64_t)avgbytespersec * rb->seek_time)
+                  / (1000LL*blockalign)) * blockalign;
+        if (newpos > numbytes)
+            break;
+        if (rb->seek_buffer(firstblockposn + newpos)) {
+            bytesdone = newpos;
+        }
+        rb->seek_time = 0;
+    }
+    wavbuf=rb->request_buffer(&n,chunksize);
+    wavbuf8 = (uint8_t*)wavbuf;
+
+    if (n==0)
+        break; /* End of stream */
 
-    nsamples=(n/bytespersample);
+    if (bytesdone + n > numbytes) {
+        n = numbytes - bytesdone;
+        endofstream = 1;
+    }
 
-    /* WAV files can contain extra data at the end - so we can't just
-       process until the end of the file */
+    wavbufsize = sizeof(int16_samples);
 
-    if (samplesdone+nsamples > totalsamples) {
-      nsamples=(totalsamples-samplesdone);
-      n=nsamples*bytespersample;
-      endofstream=1;
+    if (formattag == WAVE_FORMAT_PCM) {
+        if (bitspersample > 24) {
+            for (i=0;i<n;i+=4) {
+                int32_samples[i/4]=(int32_t)(wavbuf8[i]|(wavbuf8[i+1]<<8)|
+                                             (wavbuf8[i+2]<<16)|(wavbuf8[i+3]<<24));
+            }
+            wavbufsize = n;
+        }
+        else if (bitspersample > 16) {
+            for (i=0;i<n;i+=3) {
+                int32_samples[i/3]=(int32_t)((wavbuf8[i]<<8)|
+                           (wavbuf8[i+1]<<16)|(wavbuf8[i+2]<<24));
+           }
+            wavbufsize = n*4/3;
+        }
+        else if (bitspersample > 8) {
+            /* Byte-swap data. */
+            for (i=0;i<n/2;i++) {
+                int16_samples[i]=(int16_t)SWAB16(wavbuf[i]);
+            }
+            wavbufsize = n;
+        }
+        else {
+            for (i=0;i<n;i++) {
+                int16_samples[i] = (wavbuf8[i]<<8) - 0x8000;
+            }
+            wavbufsize = n*2;
+        }
+    }
+    else if (formattag == WAVE_FORMAT_ALAW || formattag == IBM_FORMAT_ALAW) {
+        for (i=0;i<n;i++) {
+            int16_samples[i] = alaw2linear16[wavbuf8[i]];
+        }
+        wavbufsize = n*2;
     }
+    else if (formattag == WAVE_FORMAT_MULAW || formattag == IBM_FORMAT_MULAW) {
+        for (i=0;i<n;i++) {
+            int16_samples[i] = ulaw2linear16[wavbuf8[i]];
+        }
+        wavbufsize = n*2;
+    }
+    else if (formattag == WAVE_FORMAT_DVI_ADPCM) {
+        unsigned int nblocks = chunksize/blockalign;
 
-    /* Byte-swap data */
-    for (i=0;i<n/2;i++) {
-      wavbuf[i]=SWAB16(wavbuf[i]);
+        for (i=0; i<nblocks; i++) {
+            size_t decodedsize = samplesperblock*channels;
+            if (decode_dvi_adpcm(rb, ((uint8_t*)wavbuf)+i*blockalign,
+                                 blockalign, channels, bitspersample,
+                                 int16_samples+i*samplesperblock*channels,
+                                 &decodedsize)
+                != CODEC_OK)
+                return CODEC_ERROR;
+            if (decodedsize != samplesperblock)
+                return CODEC_ERROR;
+        }
+        wavbufsize = nblocks*samplesperblock*channels*2;
+    }
+    else {
+        DEBUGF("CODEC_ERROR: unsupported format %x\n", formattag);
+        return CODEC_ERROR;
     }
 
-    samplesdone+=nsamples;
-    ci->set_elapsed(samplesdone/(ci->id3->frequency/1000));
-   
-    rb->yield();
-    while (!ci->pcmbuf_insert((unsigned char*)wavbuf, n))
-      rb->yield();
+    while (!rb->pcmbuf_insert((char*)int16_samples, wavbufsize)) {
+        rb->yield();
+    }
 
-    ci->advance_buffer(n);
+    rb->advance_buffer(n);
+    bytesdone += n;
+    if (bytesdone >= numbytes) {
+        endofstream=1;
+    }
+
+    rb->set_elapsed(bytesdone*1000LL/avgbytespersec);
   }
 
-  if (ci->request_next_track())
+  if (rb->request_next_track())
     goto next_track;
 
   return CODEC_OK;
 }
+
+static enum codec_status
+decode_dvi_adpcm(struct codec_api* rb,
+                 const uint8_t *buf,
+                 int n,
+                 uint16_t channels, uint16_t bitspersample,
+                 int16_t *pcmout,
+                 size_t *pcmoutsize)
+{
+    size_t nsamples = 0;
+    int sample[2];
+    int samplecode[32][2];
+    int i;
+    int stepindex[2];
+    int c;
+    int diff;
+    int step;
+    int codem;
+    int code;
+
+    (void)rb;
+    if (bitspersample != 4 && bitspersample != 3) {
+        DEBUGF("decode_dvi_adpcm: wrong bitspersample\n");
+        return CODEC_ERROR;
+    }
+
+    /* decode block header */
+    for(c=0; c<channels && n>=4; c++) {
+        /* decode + push first sample */
+        sample[c] = (short)(buf[0]|(buf[1]<<8));/* need cast for sign-extend */
+        pcmout[c] = sample[c];
+        nsamples++;
+        stepindex[c] = buf[2];
+        /* check for step table index overflow */
+        if (stepindex[c] > 88) {
+            DEBUGF("decode_dvi_adpcm: stepindex[%d]=%d>88\n",c,stepindex[c]);
+            return CODEC_ERROR;
+        }
+
+        buf += 4;
+        n -= 4;
+    }
+    if (bitspersample == 4) {
+        while( n>= channels*4 && (nsamples+8*channels) <= *pcmoutsize ) {
+            for (c=0; c<channels; c++) {
+                samplecode[0][c] = buf[0]&0xf;
+                samplecode[1][c] = buf[0]>>4;
+                samplecode[2][c] = buf[1]&0xf;
+                samplecode[3][c] = buf[1]>>4;
+                samplecode[4][c] = buf[2]&0xf;
+                samplecode[5][c] = buf[2]>>4;
+                samplecode[6][c] = buf[3]&0xf;
+                samplecode[7][c] = buf[3]>>4;
+                buf += 4;
+                n -= 4;
+            }
+            
+            for (i=0; i<8; i++) {
+                for (c=0; c<channels; c++) {
+                    step = dvi_adpcm_steptab[stepindex[c]];
+                    codem = samplecode[i][c];
+                    code = codem & 0x07;
+
+                    /* adjust the step table index */
+                    stepindex[c] += dvi_adpcm_indextab4[code];
+                    /* check for step table index overflow and underflow */
+                    if (stepindex[c] > 88)
+                        stepindex[c] = 88;
+                    else if (stepindex[c] < 0)
+                        stepindex[c] = 0;
+                    /* calculate the difference */
+#ifdef STRICT_IMA
+                    diff = 0;
+                    if (code & 4)
+                        diff += step;
+                    step = step >> 1;
+                    if (code & 2)
+                        diff += step;
+                    step = step >> 1;
+                    if (code & 1)
+                        diff += step;
+                    step = step >> 1;
+                    diff += step;
+#else
+                    diff = ((code+code+1) * step) >> 3; /* faster */
+#endif
+                    /* check the sign bit */
+                    /* check for overflow and underflow errors */
+                    if (code != codem) {
+                        sample[c] -= diff;
+                        if (sample[c] < -32768)
+                            sample[c] = -32768;
+                    }
+                    else {
+                        sample[c] += diff;
+                        if (sample[c] > 32767)
+                            sample[c] = 32767;
+                    }
+                    /* output the new sample */
+                    pcmout[nsamples] = sample[c];
+                    nsamples++;
+                }
+            }
+        }
+    }
+    else {                  /* bitspersample == 3 */
+        while( n>= channels*12 && (nsamples+32*channels) <= *pcmoutsize) {
+            for (c=0; c<channels; c++) {
+                uint16_t bitstream = 0;
+                int bitsread = 0;
+                for (i=0; i<32 && n>0; i++) {
+                    if (bitsread < 3) {
+                        /* read 8 more bits */
+                        bitstream |= buf[0]<<bitsread;
+                        bitsread += 8;
+                        n--;
+                        buf++;
+                    }
+                    samplecode[i][c] = bitstream & 7;
+                    bitstream = bitstream>>3;
+                    bitsread -= 3;
+                }
+                if (bitsread != 0) {
+                    /* 32*3 = 3 words, so we should end with bitsread==0 */
+                    DEBUGF("decode_dvi_adpcm: error in implementation\n");
+                    return CODEC_ERROR;
+                }
+            }
+            
+            for (i=0; i<32; i++) {
+                for (c=0; c<channels; c++) {
+                    step = dvi_adpcm_steptab[stepindex[c]];
+                    codem = samplecode[i][c];
+                    code = codem & 0x03;
+
+                    /* adjust the step table index */
+                    stepindex[c] += dvi_adpcm_indextab3[code];
+                    /* check for step table index overflow and underflow */
+                    if (stepindex[c] > 88)
+                        stepindex[c] = 88;
+                    else if (stepindex[c] < 0)
+                        stepindex[c] = 0;
+                    /* calculate the difference */
+#ifdef STRICT_IMA
+                    diff = 0;
+                    if (code & 2)
+                        diff += step;
+                    step = step >> 1;
+                    if (code & 1)
+                        diff += step;
+                    step = step >> 1;
+                    diff += step;
+#else
+                    diff = ((code+code+1) * step) >> 3; /* faster */
+#endif
+                    /* check the sign bit */
+                    /* check for overflow and underflow errors */
+                    if (code != codem) {
+                        sample[c] -= diff;
+                        if (sample[c] < -32768)
+                            sample[c] = -32768;
+                    }
+                    else {
+                        sample[c] += diff;
+                        if (sample[c] > 32767)
+                            sample[c] = 32767;
+                    }
+                    /* output the new sample */
+                    pcmout[nsamples] = sample[c];
+                    nsamples++;
+                }
+            }
+        }
+    }
+
+    if (nsamples > *pcmoutsize) {
+        DEBUGF("decode_dvi_adpcm: output buffer overflow!\n");
+        return CODEC_ERROR;
+    }
+    *pcmoutsize = nsamples;
+    if (n!=0) {
+        DEBUGF("decode_dvi_adpcm: n=%d unprocessed bytes\n",n);
+    }
+    return CODEC_OK;
+}
+