Add speex to trunk/deps/third_party/....

speex/include/speex/speex_bits.h

+/* Copyright (C) 2002 Jean-Marc Valin */
+/**
+   @file speex_bits.h
+   @brief Handles bit packing/unpacking
+*/
+/*
+   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 the Xiph.org Foundation nor the names of its
+   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 FOUNDATION 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.
+
+*/
+
+#ifndef BITS_H
+#define BITS_H
+/** @defgroup SpeexBits SpeexBits: Bit-stream manipulations
+ *  This is the structure that holds the bit-stream when encoding or decoding
+ * with Speex. It allows some manipulations as well.
+ *  @{
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Bit-packing data structure representing (part of) a bit-stream. */
+typedef struct SpeexBits {
+   char *chars;   /**< "raw" data */
+   int   nbBits;  /**< Total number of bits stored in the stream*/
+   int   charPtr; /**< Position of the byte "cursor" */
+   int   bitPtr;  /**< Position of the bit "cursor" within the current char */
+   int   owner;   /**< Does the struct "own" the "raw" buffer (member "chars") */
+   int   overflow;/**< Set to one if we try to read past the valid data */
+   int   buf_size;/**< Allocated size for buffer */
+   int   reserved1; /**< Reserved for future use */
+   void *reserved2; /**< Reserved for future use */
+} SpeexBits;
+
+/** Initializes and allocates resources for a SpeexBits struct */
+void speex_bits_init(SpeexBits *bits);
+
+/** Initializes SpeexBits struct using a pre-allocated buffer*/
+void speex_bits_init_buffer(SpeexBits *bits, void *buff, int buf_size);
+
+/** Sets the bits in a SpeexBits struct to use data from an existing buffer (for decoding without copying data) */
+void speex_bits_set_bit_buffer(SpeexBits *bits, void *buff, int buf_size);
+
+/** Frees all resources associated to a SpeexBits struct. Right now this does nothing since no resources are allocated, but this could change in the future.*/
+void speex_bits_destroy(SpeexBits *bits);
+
+/** Resets bits to initial value (just after initialization, erasing content)*/
+void speex_bits_reset(SpeexBits *bits);
+
+/** Rewind the bit-stream to the beginning (ready for read) without erasing the content */
+void speex_bits_rewind(SpeexBits *bits);
+
+/** Initializes the bit-stream from the data in an area of memory */
+void speex_bits_read_from(SpeexBits *bits, char *bytes, int len);
+
+/** Append bytes to the bit-stream
+ * 
+ * @param bits Bit-stream to operate on
+ * @param bytes pointer to the bytes what will be appended
+ * @param len Number of bytes of append
+ */
+void speex_bits_read_whole_bytes(SpeexBits *bits, char *bytes, int len);
+
+/** Write the content of a bit-stream to an area of memory
+ * 
+ * @param bits Bit-stream to operate on
+ * @param bytes Memory location where to write the bits
+ * @param max_len Maximum number of bytes to write (i.e. size of the "bytes" buffer)
+ * @return Number of bytes written to the "bytes" buffer
+*/
+int speex_bits_write(SpeexBits *bits, char *bytes, int max_len);
+
+/** Like speex_bits_write, but writes only the complete bytes in the stream. Also removes the written bytes from the stream */
+int speex_bits_write_whole_bytes(SpeexBits *bits, char *bytes, int max_len);
+
+/** Append bits to the bit-stream
+ * @param bits Bit-stream to operate on
+ * @param data Value to append as integer
+ * @param nbBits number of bits to consider in "data"
+ */
+void speex_bits_pack(SpeexBits *bits, int data, int nbBits);
+
+/** Interpret the next bits in the bit-stream as a signed integer
+ *
+ * @param bits Bit-stream to operate on
+ * @param nbBits Number of bits to interpret
+ * @return A signed integer represented by the bits read
+ */
+int speex_bits_unpack_signed(SpeexBits *bits, int nbBits);
+
+/** Interpret the next bits in the bit-stream as an unsigned integer
+ *
+ * @param bits Bit-stream to operate on
+ * @param nbBits Number of bits to interpret
+ * @return An unsigned integer represented by the bits read
+ */
+unsigned int speex_bits_unpack_unsigned(SpeexBits *bits, int nbBits);
+
+/** Returns the number of bytes in the bit-stream, including the last one even if it is not "full"
+ *
+ * @param bits Bit-stream to operate on
+ * @return Number of bytes in the stream
+ */
+int speex_bits_nbytes(SpeexBits *bits);
+
+/** Same as speex_bits_unpack_unsigned, but without modifying the cursor position 
+ * 
+ * @param bits Bit-stream to operate on
+ * @param nbBits Number of bits to look for
+ * @return Value of the bits peeked, interpreted as unsigned
+ */
+unsigned int speex_bits_peek_unsigned(SpeexBits *bits, int nbBits);
+
+/** Get the value of the next bit in the stream, without modifying the
+ * "cursor" position 
+ * 
+ * @param bits Bit-stream to operate on
+ * @return Value of the bit peeked (one bit only)
+ */
+int speex_bits_peek(SpeexBits *bits);
+
+/** Advances the position of the "bit cursor" in the stream 
+ *
+ * @param bits Bit-stream to operate on
+ * @param n Number of bits to advance
+ */
+void speex_bits_advance(SpeexBits *bits, int n);
+
+/** Returns the number of bits remaining to be read in a stream
+ *
+ * @param bits Bit-stream to operate on
+ * @return Number of bits that can still be read from the stream
+ */
+int speex_bits_remaining(SpeexBits *bits);
+
+/** Insert a terminator so that the data can be sent as a packet while auto-detecting 
+ * the number of frames in each packet 
+ *
+ * @param bits Bit-stream to operate on
+ */
+void speex_bits_insert_terminator(SpeexBits *bits);
+
+#ifdef __cplusplus
+}
+#endif
+
+/* @} */
+#endif