/*=============================================================================?
?*?????FileName:?rtp.c?
?*?????????Desc:?rtp?payload?h.264?data?
?*???????Author:?licaibiao?
?*???LastChange:?2017-04-07??
?*?=============================================================================*/
#include???
#include???
#include???
#include?????
#include???
#include???
#include?
#include???
#include??
#include??
#include?“rtp.h“??

//#define?DEBUG_LOG

typedef?struct??
{??
	int?startcodeprefix_len;??????//!?4?for?parameter?sets?and?first?slice?in?picture?3?for?everything?else?（suggested）??
	unsigned?len;?????????????????//!?Length?of?the?NAL?unit?（Excluding?the?start?code?which?does?not?belong?to?the?NALU）??
	unsigned?max_size;????????????//!?Nal?Unit?Buffer?size??
	int?forbidden_bit;????????????//!?should?be?always?FALSE??
	int?nal_reference_idc;????????//!?NALU_PRIORITY_xxxx??
	int?nal_unit_type;????????????//!?NALU_TYPE_xxxx??????
	char?*buf;????????????????????//!?contains?the?first?byte?followed?by?the?EBSP??
	unsigned?short?lost_packets;??//!?true?if?packet?loss?is?detected??
}?NALU_t;??

FILE?*bits?=?NULL;??????????????//!static?int?FindStartCode2?（unsigned?char?*Buf）;//查找開始字符0x000001??
static?int?FindStartCode3?（unsigned?char?*Buf）;//查找開始字符0x00000001??
static?int?info2=0;
static?int?info3=0;?
RTP_FIXED_HEADER?*rtp_hdr;??
NALU_HEADER??????*nalu_hdr;??
FU_INDICATOR?????*fu_ind;??
FU_HEADER????????*fu_hdr;??

NALU_t?*AllocNALU（int?buffersize）??
{??
	NALU_t?*n;??
	if?（（n?=?（NALU_t*）calloc?（1?sizeof?（NALU_t）））?==?NULL）??
	{??
		printf（“AllocNALU:?n“）;??
		exit（0）;??
	}??
	n->max_size?=?buffersize;??
	if（（n->buf?=?（char*）calloc?（buffersize?sizeof?（char）））?==?NULL）??
	{??
		free?（n）;??
		printf?（“AllocNALU:?n->buf“）;??
		exit（0）;??
	}??
	return?n;??
}??

void?FreeNALU（NALU_t?*n）??
{??
	if?（n）??
	{??
		if?（n->buf）??
		{??
			free（n->buf）;??
			n->buf=NULL;??
		}??
		free?（n）;??
	}??
}??

void?OpenBitstreamFile?（char?*fn）??
{??
	if?（NULL?==?（bits?=?fopen（fn?“rb“）））??
	{??
		printf（“open?file?error\n“）;??
		exit（0）;??
	}??
}??

//這個函數(shù)輸入為一個NAL結(jié)構(gòu)體，主要功能為得到一個完整的NALU并保存在NALU_t的buf中，獲取他的長度，填充FIDCTYPE位。??
//并且返回兩個開始字符之間間隔的字節(jié)數(shù)，即包含有前綴的NALU的長度
//前綴之后的第一個字節(jié)為?NALU_HEADER???
int?GetAnnexbNALU?（NALU_t?*nalu）??
{??
	int?pos?=?0;??
	int?rewind;?
	int?StartCodeFound;
	unsigned?char?*Buf;??
	
	if?（（Buf?=?（unsigned?char*）calloc?（nalu->max_size??sizeof（char）））?==?NULL）
		printf?（“GetAnnexbNALU:?Could?not?allocate?Buf?memory\n“）;??
	
	printf（“nalu->max_size=%d\n“（int）nalu->max_size）;
	memset（Buf0nalu->max_size）;
	nalu->startcodeprefix_len?=?3;//初始化碼流序列的開始字符為3個字節(jié)??
	if?（3?!=?fread?（Buf?1?3?bits））//從碼流中讀3個字節(jié)??
	{??
		free（Buf）;??
		return?0;??
	}??
	info2?=?FindStartCode2?（Buf）;//判斷是否為0x000001???
	if（info2?!=?1）???
	{??
		//如果不是，