frame.h

一个非常美妙的proxy。功能强大。基于sip的协议。如果还要的话

/*! Indicate video frame update */
#define AST_CONTROL_VIDUPDATE		18

#define AST_SMOOTHER_FLAG_G729		(1 << 0)

/* Option identifiers and flags */
#define AST_OPTION_FLAG_REQUEST		0
#define AST_OPTION_FLAG_ACCEPT		1
#define AST_OPTION_FLAG_REJECT		2
#define AST_OPTION_FLAG_QUERY		4
#define AST_OPTION_FLAG_ANSWER		5
#define AST_OPTION_FLAG_WTF		6

/*! Verify touchtones by muting audio transmission 
	(and reception) and verify the tone is still present */
#define AST_OPTION_TONE_VERIFY		1		

/*! Put a compatible channel into TDD (TTY for the hearing-impared) mode */
#define	AST_OPTION_TDD			2

/*! Relax the parameters for DTMF reception (mainly for radio use) */
#define	AST_OPTION_RELAXDTMF		3

/*! Set (or clear) Audio (Not-Clear) Mode */
#define	AST_OPTION_AUDIO_MODE		4

/*! Set channel transmit gain 
 * Option data is a single signed char
   representing number of decibels (dB)
   to set gain to (on top of any gain
   specified in channel driver)
*/
#define AST_OPTION_TXGAIN		5

/*! Set channel receive gain
 * Option data is a single signed char
   representing number of decibels (dB)
   to set gain to (on top of any gain
   specified in channel driver)
*/
#define AST_OPTION_RXGAIN		6

struct ast_option_header {
	/* Always keep in network byte order */
#if __BYTE_ORDER == __BIG_ENDIAN
        u_int16_t flag:3;
        u_int16_t option:13;
#else
#if __BYTE_ORDER == __LITTLE_ENDIAN
        u_int16_t option:13;
        u_int16_t flag:3;
#else
#error Byte order not defined
#endif
#endif
		u_int8_t data[0];
};

/*! \brief  Requests a frame to be allocated 
 * 
 * \param source 
 * Request a frame be allocated.  source is an optional source of the frame, 
 * len is the requested length, or "0" if the caller will supply the buffer 
 */
#if 0 /* Unimplemented */
struct ast_frame *ast_fralloc(char *source, int len);
#endif

/*!  \brief Frees a frame 
 * \param fr Frame to free
 * Free a frame, and the memory it used if applicable
 * \return no return.
 */
void ast_frfree(struct ast_frame *fr);

/*! \brief Copies a frame 
 * \param fr frame to act upon
 * Take a frame, and if it's not been malloc'd, make a malloc'd copy
 * and if the data hasn't been malloced then make the
 * data malloc'd.  If you need to store frames, say for queueing, then
 * you should call this function.
 * \return Returns a frame on success, NULL on error
 */
struct ast_frame *ast_frisolate(struct ast_frame *fr);

/*! \brief Copies a frame 
 * \param fr frame to copy
 * Dupliates a frame -- should only rarely be used, typically frisolate is good enough
 * \return Returns a frame on success, NULL on error
 */
struct ast_frame *ast_frdup(struct ast_frame *fr);

/*! \brief Reads a frame from an fd
 * Read a frame from a stream or packet fd, as written by fd_write
 * \param fd an opened fd to read from
 * \return returns a frame on success, NULL on error
 */
struct ast_frame *ast_fr_fdread(int fd);

/*! Writes a frame to an fd
 * Write a frame to an fd
 * \param fd Which fd to write to
 * \param frame frame to write to the fd
 * \return Returns 0 on success, -1 on failure
 */
int ast_fr_fdwrite(int fd, struct ast_frame *frame);

/*! \brief Sends a hangup to an fd 
 * Send a hangup (NULL equivalent) on an fd
 * \param fd fd to write to
 * \return Returns 0 on success, -1 on failure
 */
int ast_fr_fdhangup(int fd);

void ast_swapcopy_samples(void *dst, const void *src, int samples);

/* Helpers for byteswapping native samples to/from 
   little-endian and big-endian. */
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define ast_frame_byteswap_le(fr) do { ; } while(0)
#define ast_frame_byteswap_be(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0)
#else
#define ast_frame_byteswap_le(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0)
#define ast_frame_byteswap_be(fr) do { ; } while(0)
#endif


/*! \brief Get the name of a format
 * \param format id of format
 * \return A static string containing the name of the format or "UNKN" if unknown.
 */
extern char* ast_getformatname(int format);

/*! \brief Get the names of a set of formats
 * \param buf a buffer for the output string
 * \param size size of buf (bytes)
 * \param format the format (combined IDs of codecs)
 * Prints a list of readable codec names corresponding to "format".
 * ex: for format=AST_FORMAT_GSM|AST_FORMAT_SPEEX|AST_FORMAT_ILBC it will return "0x602 (GSM|SPEEX|ILBC)"
 * \return The return value is buf.
 */
extern char* ast_getformatname_multiple(char *buf, size_t size, int format);

/*!
 * \brief Gets a format from a name.
 * \param name string of format
 * \return This returns the form of the format in binary on success, 0 on error.
 */
extern int ast_getformatbyname(char *name);

/*! \brief Get a name from a format 
 * Gets a name from a format
 * \param codec codec number (1,2,4,8,16,etc.)
 * \return This returns a static string identifying the format on success, 0 on error.
 */
extern char *ast_codec2str(int codec);

struct ast_smoother;

extern struct ast_format_list *ast_get_format_list_index(int index);
extern struct ast_format_list *ast_get_format_list(size_t *size);
extern struct ast_smoother *ast_smoother_new(int bytes);
extern void ast_smoother_set_flags(struct ast_smoother *smoother, int flags);
extern int ast_smoother_get_flags(struct ast_smoother *smoother);
extern void ast_smoother_free(struct ast_smoother *s);
extern void ast_smoother_reset(struct ast_smoother *s, int bytes);
extern int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap);
extern struct ast_frame *ast_smoother_read(struct ast_smoother *s);
#define ast_smoother_feed(s,f) __ast_smoother_feed(s, f, 0)
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 1)
#define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 0)
#else
#define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 0)
#define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 1)
#endif

extern void ast_frame_dump(char *name, struct ast_frame *f, char *prefix);

/*! \brief Initialize a codec preference to "no preference" */
extern void ast_codec_pref_init(struct ast_codec_pref *pref);

/*! \brief Codec located at  a particular place in the preference index */
extern int ast_codec_pref_index(struct ast_codec_pref *pref, int index);

/*! \brief Remove a codec from a preference list */
extern void ast_codec_pref_remove(struct ast_codec_pref *pref, int format);

/*! \brief Append a codec to a preference list, removing it first if it was already there */
extern int ast_codec_pref_append(struct ast_codec_pref *pref, int format);

/*! \brief Select the best format according to preference list from supplied options. 
   If "find_best" is non-zero then if nothing is found, the "Best" format of 
   the format list is selected, otherwise 0 is returned. */
extern int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best);

/*! \brief Parse an "allow" or "deny" line and update the mask and pref if provided */
extern void ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing);

/*! \brief Dump codec preference list into a string */
extern int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size);

/*! \brief Shift a codec preference list up or down 65 bytes so that it becomes an ASCII string */
extern void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right);

/*! \brief Returns the number of samples contained in the frame */
extern int ast_codec_get_samples(struct ast_frame *f);

/*! \brief Returns the number of bytes for the number of samples of the given format */
extern int ast_codec_get_len(int format, int samples);

/*! \brief Gets duration in ms of interpolation frame for a format */
static inline int ast_codec_interp_len(int format) 
{ 
	return (format == AST_FORMAT_ILBC) ? 30 : 20;
}

/*!
  \brief Adjusts the volume of the audio samples contained in a frame.
  \param f The frame containing the samples (must be AST_FRAME_VOICE and AST_FORMAT_SLINEAR)
  \param adjustment The number of dB to adjust up or down.
  \return 0 for success, non-zero for an error
 */
int ast_frame_adjust_volume(struct ast_frame *f, int adjustment);

/*!
  \brief Sums two frames of audio samples.
  \param f1 The first frame (which will contain the result)
  \param f2 The second frame
  \return 0 for success, non-zero for an error

  The frames must be AST_FRAME_VOICE and must contain AST_FORMAT_SLINEAR samples,
  and must contain the same number of samples.
 */
int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2);

#if defined(__cplusplus) || defined(c_plusplus)
}
#endif

#endif /* _ASTERISK_FRAME_H */