www.pudn.com > VC_Standalone.rar > stream.cpp
/*************************************************************************
AVS1-P2视频解码器源码
版权所有：联合信源数字音视频技术（北京）有限公司, (c) 2005-2006
AVS1-P2 Video Decoder Source Code
(c) Copyright, NSCC All Rights Reserved, 2005-2006
*************************************************************************
Distributed under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*************************************************************************/
/*************************************************************************
文件名称: stream.cpp
描 述: 与码流处理相关的一些函数
*************************************************************************/
/*************************************************************************
Revision History
data Modification Author
2005-2-8 Created jthou
*************************************************************************/
#include "define.h"
#include "stream.h"
#include "vlc.h"
#include "global.h"
#include "macroblock.h"
#include "loopfilter.h"
AVS_DWORD SeqenceHeader(const AVS_BYTE* pbData, AVS_DWORD dwDataLen, SEQENCEINFO* Info)
{
if(dwDataLen < 18)
return AVS_NOT_ENOUGH_DATA;
DWORD Left;
FindNextPicOrEndStartCode(pbData, dwDataLen, &Left);
const AVS_BYTE* pbCurrent = pbData;
AVS_DWORD bitOffset = 32;
AVS_DWORD profile_id = read_bits(pbCurrent, &bitOffset, 8);
AVS_DWORD level_id = read_bits(pbCurrent, &bitOffset, 8);
AVS_BOOL progressive_sequence = read_bits(pbCurrent, &bitOffset, 1);
AVS_DWORD horizontal_size = read_bits(pbCurrent, &bitOffset, 14);
AVS_DWORD vertical_size = read_bits(pbCurrent, &bitOffset, 14);
AVS_DWORD chromat_fromat = read_bits(pbCurrent, &bitOffset, 2);
AVS_DWORD sample_precision = read_bits(pbCurrent, &bitOffset, 3);
AVS_DWORD aspect_ratio = read_bits(pbCurrent, &bitOffset, 4);
AVS_DWORD frame_rate_code = read_bits(pbCurrent, &bitOffset, 4);
AVS_DWORD bit_rate_lower = read_bits(pbCurrent, &bitOffset, 18);
AVS_BOOL market_bit = read_bits(pbCurrent, &bitOffset, 1);
AVS_DWORD bit_rate_upper = read_bits(pbCurrent, &bitOffset, 12);
AVS_BOOL low_dlay = read_bits(pbCurrent, &bitOffset, 1);
Info->dwProfile = profile_id;
Info->dwLevel = level_id;
Info->bProgressive = progressive_sequence;
Info->dwWidth = horizontal_size;
Info->dwHeight = vertical_size;
Info->fFrameRate = fPictureRates[frame_rate_code];
Info->dwChromaFormat = chromat_fromat;
Info->dwAspectRatio = aspect_ratio;
Info->bLowDelay = low_dlay;
Info->dwMbWidth = (horizontal_size+15)/16;
Info->dwMbHeight = (vertical_size+15)/16; //???
return dwDataLen-Left;
}
AVS_DWORD SliceHeader(const AVS_BYTE* pbData, AVS_DWORD dwDataLen, AVS_DWORD dwMbIndex, AVS_DWORD* pdwBitOffset, STREAMINFO* StrmInfo)
{
const AVS_BYTE* pbCurrent = pbData;
AVS_DWORD dwLeft = dwDataLen;
AVS_DWORD MbWidth = StrmInfo->SeqInfo.dwMbWidth;
AVS_DWORD MbHeight = StrmInfo->SeqInfo.dwMbHeight;
AVS_BOOL slice_weighting_flag = FALSE;
AVS_DWORD dwMbNum = MbWidth * MbHeight;
AVS_DWORD BitOffset = 0;
AVS_DWORD mb_skip_run = 0;
//AVS_DWORD mb_line_num = u(pbCurrent, &dwBitOffset, dwLeft, 8);
AVS_DWORD slice_vertical_position_extention = 0;
if(dwMbIndex == 0)
{
if(StrmInfo->SeqInfo.dwWidth > 2800)
slice_vertical_position_extention = read_bits(pbCurrent, &BitOffset, 3);
if(!StrmInfo->ImgInfo.bFixedPictureQp) //?
{
StrmInfo->SlcInfo.bFixedSliceQp = read_bits(pbCurrent, &BitOffset,1);
StrmInfo->SlcInfo.dwSliceQp = read_bits(pbCurrent, &BitOffset, 6);
}
}
if(StrmInfo->ImgInfo.dwImageType != I_IMG ||
(StrmInfo->ImgInfo.bPictureStructure == 0 && dwMbIndex >= MbWidth*MbHeight/2 ))
{
// if(StrmInfo->ImgInfo.bSkipModeFlag)
// mb_skip_run = ue(pbCurrent, &BitOffset, dwLeft);
slice_weighting_flag = read_bits(pbCurrent, &BitOffset, 1);
if(slice_weighting_flag)
{
for(AVS_INT i=0; i<2; i++)
{
StrmInfo->SlcInfo.LumaScale[i] = read_bits(pbCurrent, &BitOffset, 8);
StrmInfo->SlcInfo.LumaShift[i] = read_bits(pbCurrent, &BitOffset, 8);
BitOffset += 1; // marker_bit
StrmInfo->SlcInfo.ChromaScale[i] = read_bits(pbCurrent, &BitOffset, 8);
StrmInfo->SlcInfo.ChromaShift[i] = read_bits(pbCurrent, &BitOffset, 8);
}
StrmInfo->SlcInfo.bMbWeightingFlag = read_bits(pbCurrent, &BitOffset, 8);
}
}
*pdwBitOffset += BitOffset;
return AVS_NOERROR;
}
AVS_DWORD GetImgHeaderInfo(const AVS_BYTE* pbData,AVS_DWORD dwDataLen, AVS_DWORD* dwBitoffset, STREAMINFO* Info)
{
const AVS_BYTE* pbCurrent = pbData;
AVS_DWORD bitOffset = 32;
AVS_DWORD dwCode = *(AVS_DWORD*)pbCurrent;
if(DWORD_SWAP(dwCode) == I_FRAME_START_CODE)
{
AVS_DWORD bbv_dwlay = read_bits(pbCurrent, &bitOffset, 16);
AVS_BOOL time_code_flag = read_bits(pbCurrent, &bitOffset, 1);
AVS_DWORD time_code = 0;
if(time_code_flag == 1)
time_code = read_bits(pbCurrent, &bitOffset, 24);//u(pbData, &bitOffset, dwDataLen, 24);
AVS_DWORD picture_distance = read_bits(pbCurrent, &bitOffset, 8);
AVS_DWORD bbv_check_times = 0;
if(Info->SeqInfo.bLowDelay)
bbv_check_times = ue(pbData, &bitOffset, dwDataLen);
AVS_BOOL progressive_frame = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL picture_structure = FALSE;
if(progressive_frame == 0)
picture_structure = read_bits(pbCurrent, &bitOffset, 1);
else
picture_structure = 1;
AVS_BOOL top_field_first = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL repeat_first_field = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL fixed_picture_qp = read_bits(pbCurrent, &bitOffset, 1);
AVS_DWORD picture_qp = read_bits(pbCurrent, &bitOffset, 6);
AVS_BOOL skip_mode_flag = 0;
if(progressive_frame == 0)
{
if(picture_structure == 0)
skip_mode_flag = read_bits(pbCurrent, &bitOffset, 1);
}
bitOffset += 4; //reserved_bits
AVS_DWORD alpha_c_offset = 0;
AVS_DWORD beta_offset = 0;
AVS_BOOL loop_filter_disable = read_bits(pbCurrent, &bitOffset, 1);
if(!loop_filter_disable)
{
AVS_BOOL loop_filter_parameter_flag = read_bits(pbCurrent, &bitOffset, 1);
if(loop_filter_parameter_flag)
{
alpha_c_offset = se(pbCurrent, &bitOffset, dwDataLen);
beta_offset = se(pbCurrent, &bitOffset, dwDataLen);
}
}
IMAGEINFO* imgInfo = &(Info->ImgInfo);
imgInfo->dwImageType = I_IMG;
imgInfo->dwPictureDistance = picture_distance;
imgInfo->bProgressiveFrame = progressive_frame;
imgInfo->bPictureStructure = picture_structure;
imgInfo->bTopFieldFirst = top_field_first;
imgInfo->bFixedPictureQp = fixed_picture_qp;
imgInfo->bRepeatFirstField = repeat_first_field;
imgInfo->dwPictureQp = picture_qp;
imgInfo->bSkipModeFlag = skip_mode_flag;
imgInfo->bLoopFilterDisable = loop_filter_disable;
imgInfo->iAlphaCOffset = alpha_c_offset;
imgInfo->iBetaOffset = beta_offset;
*dwBitoffset = bitOffset;
return AVS_NOERROR;
}
else if(DWORD_SWAP(dwCode) == PB_FRAME_START_CODE)
{
AVS_DWORD bbv_dwlay = read_bits(pbCurrent, &bitOffset, 16);
AVS_DWORD picture_coding_type = read_bits(pbCurrent, &bitOffset, 2);
AVS_DWORD picture_distance = read_bits(pbCurrent, &bitOffset, 8);
AVS_DWORD bbv_check_times = 0;
if(Info->SeqInfo.bLowDelay)
bbv_check_times = ue(pbData, &bitOffset, dwDataLen);
AVS_BOOL progressive_frame = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL picture_structure = 0;
AVS_BOOL advanced_pred_mode_disable;
if(progressive_frame == 0)
{
picture_structure = read_bits(pbCurrent, &bitOffset, 1);
if(!picture_structure)
advanced_pred_mode_disable = read_bits(pbCurrent, &bitOffset, 1);
}
else
{
picture_structure = TRUE;
}
AVS_BOOL top_field_first = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL repeat_first_field = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL fixed_picture_qp = read_bits(pbCurrent, &bitOffset, 1);
AVS_DWORD picture_qp = read_bits(pbCurrent, &bitOffset, 6);
AVS_BOOL picture_reference_flag = FALSE;
if(!(picture_coding_type==2 && picture_structure==1))
picture_reference_flag = read_bits(pbCurrent, &bitOffset, 1);
bitOffset += 4; //reserved_bits
AVS_BOOL skip_mode_flag = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL loop_filter_disable = read_bits(pbCurrent, &bitOffset, 1);
AVS_BOOL loop_filter_parameter_flag = FALSE;
AVS_DWORD alpha_c_offset = 0;
AVS_DWORD beta_offset = 0;
if(!loop_filter_disable)
{
loop_filter_parameter_flag = read_bits(pbCurrent, &bitOffset, 1);
if(loop_filter_parameter_flag)
{
alpha_c_offset = se(pbData, &bitOffset, dwDataLen);
beta_offset = se(pbData, &bitOffset, dwDataLen);
}
}
IMAGEINFO* imgInfo = &(Info->ImgInfo);
if(picture_coding_type == 1)
imgInfo->dwImageType = P_IMG;
else
imgInfo->dwImageType = B_IMG;
imgInfo->bFixedPictureQp = fixed_picture_qp;
imgInfo->bLoopFilterDisable = loop_filter_disable;
imgInfo->bPictureReferenceFlag = picture_reference_flag;
imgInfo->bPictureStructure = picture_structure;
imgInfo->bProgressiveFrame = progressive_frame;
imgInfo->bRepeatFirstField = repeat_first_field;
imgInfo->bSkipModeFlag = skip_mode_flag;
imgInfo->bTopFieldFirst = top_field_first;
imgInfo->iAlphaCOffset = alpha_c_offset;
imgInfo->iBetaOffset = beta_offset;
imgInfo->dwPictureDistance = picture_distance;
imgInfo->dwPictureQp = picture_qp;
*dwBitoffset = bitOffset;
return AVS_NOERROR;
}
else
{
return AVS_INVALID_PIC_START_CODE;
}
}
/************************************************************************/
/* 函数功能：寻找下一个起始码 */
/************************************************************************/
AVS_BOOL FindNextStartCode(const AVS_BYTE* pbData, AVS_DWORD dwDataLen, AVS_DWORD* dwLeft)
{
const AVS_BYTE* pbCurrent = pbData+4;
AVS_DWORD Left = dwDataLen-4;
while (Left>4 &&
(*(AVS_DWORD *)pbCurrent & 0x00FFFFFF) != 0x00010000)
{
pbCurrent ++;
Left --;
}
if(Left > 4)
{
*dwLeft = Left;
return TRUE;
}
return FALSE;
}