#include
#include
#include
#include
typedef
unsigned
intuint
; typedef
unsigned
char
byte
; typedef
unsigned
long
dword
; uint
ue(byte
*pbuff,
uint
nlen,
uint
&nstartbit)
nzeronum++;
nstartbit++;
} nstartbit ++;
//計算結果
dword
dwret = 0;
for(
uint
i=0; i
nstartbit++;
} return
(1 << nzeronum) - 1 + dwret;
} int
se(byte
*pbuff,
uint
nlen,
uint
&nstartbit)
dword
u(uint
bitcount,
byte
* buf,
uint
&nstartbit)
nstartbit++;
} return
dwret;
} /**
* h264的nal起始碼防競爭機制
** @param buf sps資料內容
** @無返回值
*/void
de_emulation_prevention(
byte
* buf,unsigned
int* buf_size)
} } /**
** @param buf sps資料內容
* @param nlen sps資料的長度
* @param width 影象寬度
* @param height 影象高度
* @成功則返回true , 失敗則返回false
*/bool
h264_decode_sps(
byte
* buf,unsigned
intnlen,
int&width,
int&height,
int&fps)
} } int
log2_max_frame_num_minus4=ue(buf,nlen,startbit);
intpic_order_cnt_type=ue(buf,nlen,startbit);
if( pic_order_cnt_type == 0 )
intlog2_max_pic_order_cnt_lsb_minus4=ue(buf,nlen,startbit);
else
if( pic_order_cnt_type == 1 )
intnum_ref_frames=ue(buf,nlen,startbit);
intgaps_in_frame_num_value_allowed_flag=u(1,buf,startbit);
intpic_width_in_mbs_minus1=ue(buf,nlen,startbit);
intpic_height_in_map_units_minus1=ue(buf,nlen,startbit);
width=(pic_width_in_mbs_minus1+1)*16;
height=(pic_height_in_map_units_minus1+1)*16;
intframe_mbs_only_flag=u(1,buf,startbit);
if(!frame_mbs_only_flag)
intmb_adaptive_frame_field_flag=u(1,buf,startbit);
intdirect_8x8_inference_flag=u(1,buf,startbit);
intframe_cropping_flag=u(1,buf,startbit);
if(frame_cropping_flag)
intvui_parameter_present_flag=u(1,buf,startbit);
if(vui_parameter_present_flag)
} intoverscan_info_present_flag=u(1,buf,startbit);
if(overscan_info_present_flag)
intint
video_signal_type_present_flag=u(1,buf,startbit);
if(video_signal_type_present_flag)
} intchroma_loc_info_present_flag=u(1,buf,startbit);
if(chroma_loc_info_present_flag)
inttiming_info_present_flag=u(1,buf,startbit);
if(timing_info_present_flag)
} } return
true
; }
else
return
false
; }
timing_info_present_flag等於1表示num_units_in_tick，time_scale和fixed_frame_rate_flag在位元流中存在。
timing_info_present_flag等於0表示num_units_in_tick，time_scale和fixed_frame_rate_flag在位元流中不存在。
因此，當timing_info_present_flag等於0時，無法得到位元速率，bool h264_decode_sps(byte * buf,unsigned int nlen,int &width,int &height,int &fps)引數fps返回值為0，可據此設定乙個預設幀率。
**：
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