Index: speex/include/speex/speex_bits.h |
=================================================================== |
--- speex/include/speex/speex_bits.h (revision 0) |
+++ speex/include/speex/speex_bits.h (revision 0) |
@@ -0,0 +1,174 @@ |
+/* 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 |
Property changes on: speex/include/speex/speex_bits.h |
___________________________________________________________________ |
Name: svn:executable |
+ * |