Add codecs to librbcodec.

Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libwavpack/float.c b/lib/rbcodec/codecs/libwavpack/float.c
new file mode 100644
index 0000000..6e5c4e4
--- /dev/null
+++ b/lib/rbcodec/codecs/libwavpack/float.c
@@ -0,0 +1,47 @@
+////////////////////////////////////////////////////////////////////////////
+//                           **** WAVPACK ****                            //
+//                  Hybrid Lossless Wavefile Compressor                   //
+//              Copyright (c) 1998 - 2004 Conifer Software.               //
+//                          All Rights Reserved.                          //
+//      Distributed under the BSD Software License (see license.txt)      //
+////////////////////////////////////////////////////////////////////////////
+
+// float.c
+
+#include "wavpack.h"
+
+int read_float_info (WavpackStream *wps, WavpackMetadata *wpmd)
+{
+    int bytecnt = wpmd->byte_length;
+    char *byteptr = wpmd->data;
+
+    if (bytecnt != 4)
+        return FALSE;
+
+    wps->float_flags = *byteptr++;
+    wps->float_shift = *byteptr++;
+    wps->float_max_exp = *byteptr++;
+    wps->float_norm_exp = *byteptr;
+    return TRUE;
+}
+
+/* This function converts WavPack floating point data into standard Rockbox
+ * 28-bit integers. It is assumed that clipping will be taken care of later.
+ */
+
+void float_values (WavpackStream *wps, int32_t *values, int32_t num_values)
+{
+    int shift = wps->float_max_exp - wps->float_norm_exp + wps->float_shift + 5;
+
+    if (shift > 32)
+        shift = 32;
+    else if (shift < -32)
+        shift = -32;
+
+    if (shift > 0)
+        while (num_values--)
+            *values++ <<= shift;
+    else if (shift < 0)
+        while (num_values--)
+            *values++ >>= -shift;
+}