multimedia/client/qt_gl_render/yuvgl/media/sps_decode.cpp

248 lines
6.6 KiB
C++
Raw Normal View History

2020-05-11 15:35:53 +00:00
/**
* Simplest Librtmp Send 264
*
* <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
* leixiaohua1020@126.com
* zhanghuicuc@gmail.com
* <EFBFBD>й<EFBFBD><EFBFBD><EFBFBD>ý<EFBFBD><EFBFBD>ѧ/<EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD>Ӽ<EFBFBD><EFBFBD><EFBFBD>
* Communication University of China / Digital TV Technology
* http://blog.csdn.net/leixiaohua1020
*
* <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڽ<EFBFBD><EFBFBD>ڴ<EFBFBD><EFBFBD>е<EFBFBD>H.264<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>RTMP<EFBFBD><EFBFBD>ý<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
*
*/
#include "sps_decode.h"
typedef unsigned int UINT;
typedef unsigned char BYTE;
typedef unsigned long DWORD;
UINT Ue(BYTE *pBuff, UINT nLen, UINT &nStartBit)
{
//<2F><><EFBFBD><EFBFBD>0bit<69>ĸ<EFBFBD><C4B8><EFBFBD>
UINT nZeroNum = 0;
while (nStartBit < nLen * 8)
{
if (pBuff[nStartBit / 8] & (0x80 >> (nStartBit % 8))) //&:<3A><>λ<EFBFBD>룬%ȡ<><C8A1>
{
break;
}
nZeroNum++;
nStartBit++;
}
nStartBit ++;
//<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
DWORD dwRet = 0;
for (UINT i=0; i<nZeroNum; i++)
{
dwRet <<= 1;
if (pBuff[nStartBit / 8] & (0x80 >> (nStartBit % 8)))
{
dwRet += 1;
}
nStartBit++;
}
return (1 << nZeroNum) - 1 + dwRet;
}
int Se(BYTE *pBuff, UINT nLen, UINT &nStartBit)
{
int UeVal=Ue(pBuff,nLen,nStartBit);
double k=UeVal;
int nValue=ceil(k/2);
//ceil<69><6C><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ceil<69><6C><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>ڸ<EFBFBD><DAB8><EFBFBD>ʵ<EFBFBD><CAB5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С<EFBFBD><D0A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ceil(2)=ceil(1.2)=cei(1.5)=2.00
if (UeVal % 2==0)
nValue=-nValue;
return nValue;
}
DWORD u(UINT BitCount,BYTE * buf,UINT &nStartBit)
{
DWORD dwRet = 0;
for (UINT i=0; i<BitCount; i++)
{
dwRet <<= 1;
if (buf[nStartBit / 8] & (0x80 >> (nStartBit % 8)))
{
dwRet += 1;
}
nStartBit++;
}
return dwRet;
}
/**
* H264<EFBFBD><EFBFBD>NAL<EFBFBD><EFBFBD>ʼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
*
* @param buf SPS<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
*
* @<EFBFBD>޷<EFBFBD><EFBFBD><EFBFBD>ֵ
*/
void de_emulation_prevention(BYTE* buf,unsigned int* buf_size)
{
int i=0,j=0;
BYTE* tmp_ptr = nullptr;
unsigned int tmp_buf_size=0;
int val=0;
tmp_ptr=buf;
tmp_buf_size=*buf_size;
for(i=0;i<(tmp_buf_size-2);i++)
{
//check for 0x000003
val=(tmp_ptr[i]^0x00) +(tmp_ptr[i+1]^0x00)+(tmp_ptr[i+2]^0x03);
if(val==0)
{
//kick out 0x03
for(j=i+2;j<tmp_buf_size-1;j++)
tmp_ptr[j]=tmp_ptr[j+1];
//and so we should devrease bufsize
(*buf_size)--;
}
}
return;
}
/**
* <EFBFBD><EFBFBD><EFBFBD><EFBFBD>SPS,<EFBFBD><EFBFBD>ȡ<EFBFBD><EFBFBD>Ƶͼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϣ
*
* @param buf SPS<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
* @param nLen SPS<EFBFBD><EFBFBD><EFBFBD>ݵij<EFBFBD><EFBFBD><EFBFBD>
* @param width ͼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
* @param height ͼ<EFBFBD><EFBFBD><EFBFBD>߶<EFBFBD>
* @<EFBFBD>ɹ<EFBFBD><EFBFBD>򷵻<EFBFBD>1 , ʧ<EFBFBD><EFBFBD><EFBFBD>򷵻<EFBFBD>0
*/
int h264_decode_sps(BYTE * buf,unsigned int nLen,int &width,int &height,int &fps)
{
UINT StartBit=0;
fps=0;
de_emulation_prevention(buf,&nLen);
int forbidden_zero_bit = u(1,buf,StartBit);
int nal_ref_idc = u(2,buf,StartBit);
int nal_unit_type = u(5,buf,StartBit);
if(nal_unit_type==7)
{
int profile_idc=u(8,buf,StartBit);
int constraint_set0_flag=u(1,buf,StartBit);//(buf[1] & 0x80)>>7;
int constraint_set1_flag=u(1,buf,StartBit);//(buf[1] & 0x40)>>6;
int constraint_set2_flag=u(1,buf,StartBit);//(buf[1] & 0x20)>>5;
int constraint_set3_flag=u(1,buf,StartBit);//(buf[1] & 0x10)>>4;
int reserved_zero_4bits=u(4,buf,StartBit);
int level_idc=u(8,buf,StartBit);
int seq_parameter_set_id=Ue(buf,nLen,StartBit);
if( profile_idc == 100 || profile_idc == 110 ||
profile_idc == 122 || profile_idc == 144 )
{
int chroma_format_idc=Ue(buf,nLen,StartBit);
if( chroma_format_idc == 3 )
int residual_colour_transform_flag=u(1,buf,StartBit);
int bit_depth_luma_minus8=Ue(buf,nLen,StartBit);
int bit_depth_chroma_minus8=Ue(buf,nLen,StartBit);
int qpprime_y_zero_transform_bypass_flag=u(1,buf,StartBit);
int seq_scaling_matrix_present_flag=u(1,buf,StartBit);
int seq_scaling_list_present_flag[8];
if( seq_scaling_matrix_present_flag )
{
for( int i = 0; i < 8; i++ ) {
seq_scaling_list_present_flag[i]=u(1,buf,StartBit);
}
}
}
int log2_max_frame_num_minus4=Ue(buf,nLen,StartBit);
int pic_order_cnt_type=Ue(buf,nLen,StartBit);
if( pic_order_cnt_type == 0 )
int log2_max_pic_order_cnt_lsb_minus4=Ue(buf,nLen,StartBit);
else if( pic_order_cnt_type == 1 )
{
int delta_pic_order_always_zero_flag=u(1,buf,StartBit);
int offset_for_non_ref_pic=Se(buf,nLen,StartBit);
int offset_for_top_to_bottom_field=Se(buf,nLen,StartBit);
int num_ref_frames_in_pic_order_cnt_cycle=Ue(buf,nLen,StartBit);
int *offset_for_ref_frame=new int[num_ref_frames_in_pic_order_cnt_cycle];
for( int i = 0; i < num_ref_frames_in_pic_order_cnt_cycle; i++ )
offset_for_ref_frame[i]=Se(buf,nLen,StartBit);
delete [] offset_for_ref_frame;
}
int num_ref_frames=Ue(buf,nLen,StartBit);
int gaps_in_frame_num_value_allowed_flag=u(1,buf,StartBit);
int pic_width_in_mbs_minus1=Ue(buf,nLen,StartBit);
int pic_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;
int frame_mbs_only_flag=u(1,buf,StartBit);
if(!frame_mbs_only_flag)
int mb_adaptive_frame_field_flag=u(1,buf,StartBit);
int direct_8x8_inference_flag=u(1,buf,StartBit);
int frame_cropping_flag=u(1,buf,StartBit);
if(frame_cropping_flag)
{
int frame_crop_left_offset=Ue(buf,nLen,StartBit);
int frame_crop_right_offset=Ue(buf,nLen,StartBit);
int frame_crop_top_offset=Ue(buf,nLen,StartBit);
int frame_crop_bottom_offset=Ue(buf,nLen,StartBit);
}
int vui_parameter_present_flag=u(1,buf,StartBit);
if(vui_parameter_present_flag)
{
int aspect_ratio_info_present_flag=u(1,buf,StartBit);
if(aspect_ratio_info_present_flag)
{
int aspect_ratio_idc=u(8,buf,StartBit);
if(aspect_ratio_idc==255)
{
int sar_width=u(16,buf,StartBit);
int sar_height=u(16,buf,StartBit);
}
}
int overscan_info_present_flag=u(1,buf,StartBit);
if(overscan_info_present_flag)
int overscan_appropriate_flagu=u(1,buf,StartBit);
int video_signal_type_present_flag=u(1,buf,StartBit);
if(video_signal_type_present_flag)
{
int video_format=u(3,buf,StartBit);
int video_full_range_flag=u(1,buf,StartBit);
int colour_description_present_flag=u(1,buf,StartBit);
if(colour_description_present_flag)
{
int colour_primaries=u(8,buf,StartBit);
int transfer_characteristics=u(8,buf,StartBit);
int matrix_coefficients=u(8,buf,StartBit);
}
}
int chroma_loc_info_present_flag=u(1,buf,StartBit);
if(chroma_loc_info_present_flag)
{
int chroma_sample_loc_type_top_field=Ue(buf,nLen,StartBit);
int chroma_sample_loc_type_bottom_field=Ue(buf,nLen,StartBit);
}
int timing_info_present_flag=u(1,buf,StartBit);
if(timing_info_present_flag)
{
int num_units_in_tick=u(32,buf,StartBit);
int time_scale=u(32,buf,StartBit);
fps=time_scale/(2*num_units_in_tick);
}
}
return true;
}
else
return false;
}