ref: bdf6173d6dfff6ac1627fd61bd3e0aff6a6193ec
dir: /src/h264bsd_util.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 h264bsdCountLeadingZeros h264bsdRbspTrailingBits h264bsdMoreRbspData h264bsdNextMbAddress h264bsdSetCurrImageMbPointers ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ 1. Include headers ------------------------------------------------------------------------------*/ #include "h264bsd_util.h" /*------------------------------------------------------------------------------ 2. External compiler flags -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 3. Module defines ------------------------------------------------------------------------------*/ /* look-up table for expected values of stuffing bits */ static const u32 stuffingTable[8] = {0x1,0x2,0x4,0x8,0x10,0x20,0x40,0x80}; /* look-up table for chroma quantization parameter as a function of luma QP */ const u32 h264bsdQpC[52] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19, 20,21,22,23,24,25,26,27,28,29,29,30,31,32,32,33,34,34,35,35,36,36,37,37,37, 38,38,38,39,39,39,39}; /*------------------------------------------------------------------------------ 4. Local function prototypes ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ 5.1 Function: h264bsdCountLeadingZeros Functional description: Count leading zeros in a code word. Code word is assumed to be right-aligned, last bit of the code word in the lsb of the value. Inputs: value code word length number of bits in the code word Outputs: none Returns: number of leading zeros in the code word ------------------------------------------------------------------------------*/ #ifndef H264DEC_NEON u32 h264bsdCountLeadingZeros(u32 value, u32 length) { /* Variables */ u32 zeros = 0; u32 mask = 1 << (length - 1); /* Code */ ASSERT(length <= 32); while (mask && !(value & mask)) { zeros++; mask >>= 1; } return(zeros); } #endif /*------------------------------------------------------------------------------ 5.2 Function: h264bsdRbspTrailingBits Functional description: Check Raw Byte Stream Payload (RBSP) trailing bits, i.e. stuffing. Rest of the current byte (whole byte if allready byte aligned) in the stream buffer shall contain a '1' bit followed by zero or more '0' bits. Inputs: pStrmData pointer to stream data structure Outputs: none Returns: HANTRO_OK RBSP trailing bits found HANTRO_NOK otherwise ------------------------------------------------------------------------------*/ u32 h264bsdRbspTrailingBits(strmData_t *pStrmData) { /* Variables */ u32 stuffing; u32 stuffingLength; /* Code */ ASSERT(pStrmData); ASSERT(pStrmData->bitPosInWord < 8); stuffingLength = 8 - pStrmData->bitPosInWord; stuffing = h264bsdGetBits(pStrmData, stuffingLength); if (stuffing == END_OF_STREAM) return(HANTRO_NOK); if (stuffing != stuffingTable[stuffingLength - 1]) return(HANTRO_NOK); else return(HANTRO_OK); } /*------------------------------------------------------------------------------ 5.3 Function: h264bsdMoreRbspData Functional description: Check if there is more data in the current RBSP. The standard defines this function so that there is more data if -more than 8 bits left or -last bits are not RBSP trailing bits Inputs: pStrmData pointer to stream data structure Outputs: none Returns: HANTRO_TRUE there is more data HANTRO_FALSE no more data ------------------------------------------------------------------------------*/ u32 h264bsdMoreRbspData(strmData_t *pStrmData) { /* Variables */ u32 bits; /* Code */ ASSERT(pStrmData); ASSERT(pStrmData->strmBuffReadBits <= 8 * pStrmData->strmBuffSize); bits = pStrmData->strmBuffSize * 8 - pStrmData->strmBuffReadBits; if (bits == 0) return(HANTRO_FALSE); if ( (bits > 8) || ((h264bsdShowBits32(pStrmData)>>(32-bits)) != (1 << (bits-1))) ) return(HANTRO_TRUE); else return(HANTRO_FALSE); } /*------------------------------------------------------------------------------ 5.4 Function: h264bsdNextMbAddress Functional description: Get address of the next macroblock in the current slice group. Inputs: pSliceGroupMap slice group for each macroblock picSizeInMbs size of the picture currMbAddr where to start Outputs: none Returns: address of the next macroblock 0 if none of the following macroblocks belong to same slice group as currMbAddr ------------------------------------------------------------------------------*/ u32 h264bsdNextMbAddress(u32 *pSliceGroupMap, u32 picSizeInMbs, u32 currMbAddr) { /* Variables */ u32 i, sliceGroup, tmp; /* Code */ ASSERT(pSliceGroupMap); ASSERT(picSizeInMbs); ASSERT(currMbAddr < picSizeInMbs); sliceGroup = pSliceGroupMap[currMbAddr]; i = currMbAddr + 1; tmp = pSliceGroupMap[i]; while ((i < picSizeInMbs) && (tmp != sliceGroup)) { i++; tmp = pSliceGroupMap[i]; } if (i == picSizeInMbs) i = 0; return(i); } /*------------------------------------------------------------------------------ 5.5 Function: h264bsdSetCurrImageMbPointers Functional description: Set luma and chroma pointers in image_t for current MB Inputs: image Current image mbNum number of current MB Outputs: none Returns: none ------------------------------------------------------------------------------*/ void h264bsdSetCurrImageMbPointers(image_t *image, u32 mbNum) { u32 width, height; u32 picSize; u32 row, col; u32 tmp; width = image->width; height = image->height; row = mbNum / width; col = mbNum % width; tmp = row * width; picSize = width * height; image->luma = (u8*)(image->data + col * 16 + tmp * 256); image->cb = (u8*)(image->data + picSize * 256 + tmp * 64 + col * 8); image->cr = (u8*)(image->cb + picSize * 64); }