Initial opus codec support

Synchronised with opus repo on github (https://github.com/freqmod/rockbox-opus)

Status:
* Seeking ported from speex, but fails on some cases (e.g. seek to granule 0)
* ReplayGain parsing needs to be reworked, we do vorbis-style replaygain now.
  http://wiki.xiph.org/OggOpus#Comment_Header explicitly forbids these in
  favour of R128_TRACK_GAIN tag.
* No optimisation yet, source files still nearly identical to opus upstream
* Multi-stream opus files may not be parsed correctly

Change-Id: Ia66f1027dc1d288083e3c57b2816700078376f9a
Reviewed-on: http://gerrit.rockbox.org/300
Reviewed-by: Bertrik Sikken <bertrik@sikken.nl>
Tested-by: Bertrik Sikken <bertrik@sikken.nl>

1 files changed, 77 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libopus/silk/decode_pitch.c b/lib/rbcodec/codecs/libopus/silk/decode_pitch.c
new file mode 100644
index 0000000..8190a19
--- /dev/null
+++ b/lib/rbcodec/codecs/libopus/silk/decode_pitch.c
@@ -0,0 +1,77 @@
+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+- Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+- Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+- Neither the name of Internet Society, IETF or IETF Trust, nor the 
+names of specific contributors, may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS”
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+***********************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "opus_config.h"
+#endif
+
+/***********************************************************
+* Pitch analyser function
+********************************************************** */
+#include "SigProc_FIX.h"
+#include "pitch_est_defines.h"
+
+void silk_decode_pitch(
+    opus_int16                  lagIndex,           /* I                                                                */
+    opus_int8                   contourIndex,       /* O                                                                */
+    opus_int                    pitch_lags[],       /* O    4 pitch values                                              */
+    const opus_int              Fs_kHz,             /* I    sampling frequency (kHz)                                    */
+    const opus_int              nb_subfr            /* I    number of sub frames                                        */
+)
+{
+    opus_int   lag, k, min_lag, max_lag, cbk_size;
+    const opus_int8 *Lag_CB_ptr;
+
+    if( Fs_kHz == 8 ) {
+        if( nb_subfr == PE_MAX_NB_SUBFR ) {
+            Lag_CB_ptr = &silk_CB_lags_stage2[ 0 ][ 0 ];
+            cbk_size   = PE_NB_CBKS_STAGE2_EXT;
+        } else {
+            silk_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1 );
+            Lag_CB_ptr = &silk_CB_lags_stage2_10_ms[ 0 ][ 0 ];
+            cbk_size   = PE_NB_CBKS_STAGE2_10MS;
+        }
+    } else {
+        if( nb_subfr == PE_MAX_NB_SUBFR ) {
+            Lag_CB_ptr = &silk_CB_lags_stage3[ 0 ][ 0 ];
+            cbk_size   = PE_NB_CBKS_STAGE3_MAX;
+        } else {
+            silk_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1 );
+            Lag_CB_ptr = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
+            cbk_size   = PE_NB_CBKS_STAGE3_10MS;
+        }
+    }
+
+    min_lag = silk_SMULBB( PE_MIN_LAG_MS, Fs_kHz );
+    max_lag = silk_SMULBB( PE_MAX_LAG_MS, Fs_kHz );
+    lag = min_lag + lagIndex;
+
+    for( k = 0; k < nb_subfr; k++ ) {
+        pitch_lags[ k ] = lag + matrix_ptr( Lag_CB_ptr, k, contourIndex, cbk_size );
+        pitch_lags[ k ] = silk_LIMIT( pitch_lags[ k ], min_lag, max_lag );
+    }
+}