git-svn-id: http://webrtc.googlecode.com/svn/trunk@4 4adac7df-926f-26a2-2b94-8c16560cd09d

modules/audio_coding/codecs/iSAC/fix/source/arith_routins.h

@@ -0,0 +1,160 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+/*
+ * arith_routins.h
+ *
+ * Functions for arithmetic coding.
+ *
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ARITH_ROUTINS_H_
+#define WEBRTC_MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ARITH_ROUTINS_H_
+
+#include "structs.h"
+
+
+/****************************************************************************
+ * WebRtcIsacfix_EncLogisticMulti2(...)
+ *
+ * Arithmetic coding of spectrum.
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *      - dataQ7            : data vector in Q7
+ *      - envQ8             : side info vector defining the width of the pdf
+ *                            in Q8
+ *      - lenData           : data vector length
+ *
+ * Return value             :  0 if ok,
+ *                             <0 otherwise.
+ */
+int WebRtcIsacfix_EncLogisticMulti2(
+    Bitstr_enc *streamData,
+    WebRtc_Word16 *dataQ7,
+    const WebRtc_UWord16 *env,
+    const WebRtc_Word16 lenData);
+
+
+/****************************************************************************
+ * WebRtcIsacfix_EncTerminate(...)
+ *
+ * Final call to the arithmetic coder for an encoder call. This function
+ * terminates and return byte stream.
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *
+ * Return value             : number of bytes in the stream
+ */
+WebRtc_Word16 WebRtcIsacfix_EncTerminate(Bitstr_enc *streamData);
+
+
+/****************************************************************************
+ * WebRtcIsacfix_DecLogisticMulti2(...)
+ *
+ * Arithmetic decoding of spectrum.
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *      - envQ8             : side info vector defining the width of the pdf
+ *                            in Q8
+ *      - lenData           : data vector length
+ *
+ * Input/Output:
+ *      - dataQ7            : input: dither vector, output: data vector, in Q7
+ *
+ * Return value             : number of bytes in the stream so far
+ *                            <0 if error detected
+ */
+WebRtc_Word16 WebRtcIsacfix_DecLogisticMulti2(
+    WebRtc_Word16 *data,
+    Bitstr_dec *streamData,
+    const WebRtc_Word32 *env,
+    const WebRtc_Word16 lenData);
+
+
+/****************************************************************************
+ * WebRtcIsacfix_EncHistMulti(...)
+ *
+ * Encode the histogram interval
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *      - data              : data vector
+ *      - cdf               : array of cdf arrays
+ *      - lenData           : data vector length
+ *
+ * Return value             : 0 if ok
+ *                            <0 if error detected
+ */
+int WebRtcIsacfix_EncHistMulti(
+    Bitstr_enc *streamData,
+    const WebRtc_Word16 *data,
+    const WebRtc_UWord16 **cdf,
+    const WebRtc_Word16 lenData);
+
+
+/****************************************************************************
+ * WebRtcIsacfix_DecHistBisectMulti(...)
+ *
+ * Function to decode more symbols from the arithmetic bytestream, using
+ * method of bisection.
+ * C df tables should be of size 2^k-1 (which corresponds to an
+ * alphabet size of 2^k-2)
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *      - cdf               : array of cdf arrays
+ *      - cdfSize           : array of cdf table sizes+1 (power of two: 2^k)
+ *      - lenData           : data vector length
+ *
+ * Output:
+ *      - data              : data vector
+ *
+ * Return value             : number of bytes in the stream
+ *                            <0 if error detected
+ */
+WebRtc_Word16 WebRtcIsacfix_DecHistBisectMulti(
+    WebRtc_Word16 *data,
+    Bitstr_dec *streamData,
+    const WebRtc_UWord16 **cdf,
+    const WebRtc_UWord16 *cdfSize,
+    const WebRtc_Word16 lenData);
+
+
+/****************************************************************************
+ * WebRtcIsacfix_DecHistOneStepMulti(...)
+ *
+ * Function to decode more symbols from the arithmetic bytestream, taking
+ * single step up or down at a time.
+ * cdf tables can be of arbitrary size, but large tables may take a lot of
+ * iterations.
+ *
+ * Input:
+ *      - streamData        : in-/output struct containing bitstream
+ *      - cdf               : array of cdf arrays
+ *      - initIndex         : vector of initial cdf table search entries
+ *      - lenData           : data vector length
+ *
+ * Output:
+ *      - data              : data vector
+ *
+ * Return value             : number of bytes in original stream
+ *                            <0 if error detected
+ */
+WebRtc_Word16 WebRtcIsacfix_DecHistOneStepMulti(
+    WebRtc_Word16 *data,
+    Bitstr_dec *streamData,
+    const WebRtc_UWord16 **cdf,
+    const WebRtc_UWord16 *initIndex,
+    const WebRtc_Word16 lenData);
+
+#endif /* WEBRTC_MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ARITH_ROUTINS_H_ */