mirror of
https://github.com/oxen-io/session-android.git
synced 2024-12-18 14:07:30 +00:00
175 lines
6.5 KiB
C
175 lines
6.5 KiB
C
/* 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
|