ref: ccbde503b2ccffdcd94dbadd7d03d045abed3fe1
dir: /src/h264bsd_nal_unit.c/
/* * Copyright (C) 2009 The Android Open Source Project * Modified for use by h264bsd standalone library * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /*------------------------------------------------------------------------------ Table of contents 1. Include headers 2. External compiler flags 3. Module defines 4. Local function prototypes 5. Functions h264bsdDecodeNalUnit ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ 1. Include headers ------------------------------------------------------------------------------*/ #include "h264bsd_nal_unit.h" #include "h264bsd_util.h" /*------------------------------------------------------------------------------ 2. External compiler flags -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 3. Module defines ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ 4. Local function prototypes ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ Function name: h264bsdDecodeNalUnit Functional description: Decode NAL unit header information Inputs: pStrmData pointer to stream data structure Outputs: pNalUnit NAL unit header information is stored here Returns: HANTRO_OK success HANTRO_NOK invalid NAL unit header information ------------------------------------------------------------------------------*/ u32 h264bsdDecodeNalUnit(strmData_t *pStrmData, nalUnit_t *pNalUnit) { /* Variables */ u32 tmp; /* Code */ ASSERT(pStrmData); ASSERT(pNalUnit); ASSERT(pStrmData->bitPosInWord == 0); /* forbidden_zero_bit (not checked to be zero, errors ignored) */ tmp = h264bsdGetBits(pStrmData, 1); /* Assuming that NAL unit starts from byte boundary �> don't have to check * following 7 bits for END_OF_STREAM */ if (tmp == END_OF_STREAM) return(HANTRO_NOK); tmp = h264bsdGetBits(pStrmData, 2); pNalUnit->nalRefIdc = tmp; tmp = h264bsdGetBits(pStrmData, 5); pNalUnit->nalUnitType = (nalUnitType_e)tmp; /* data partitioning NAL units not supported */ if ( (tmp == 2) || (tmp == 3) || (tmp == 4) ) { return(HANTRO_NOK); } /* nal_ref_idc shall not be zero for these nal_unit_types */ if ( ( (tmp == NAL_SEQ_PARAM_SET) || (tmp == NAL_PIC_PARAM_SET) || (tmp == NAL_CODED_SLICE_IDR) ) && (pNalUnit->nalRefIdc == 0) ) { return(HANTRO_NOK); } /* nal_ref_idc shall be zero for these nal_unit_types */ else if ( ( (tmp == NAL_SEI) || (tmp == NAL_ACCESS_UNIT_DELIMITER) || (tmp == NAL_END_OF_SEQUENCE) || (tmp == NAL_END_OF_STREAM) || (tmp == NAL_FILLER_DATA) ) && (pNalUnit->nalRefIdc != 0) ) { return(HANTRO_NOK); } return(HANTRO_OK); }