| /****************************************************************************** |
| * |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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. |
| * |
| ***************************************************************************** |
| * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore |
| */ |
| |
| #ifndef _IH264D_BITSTRM_H_ |
| #define _IH264D_BITSTRM_H_ |
| /*! |
| ************************************************************************* |
| * \file ih264d_bitstrm.h |
| * |
| * \brief |
| * Contains all the declarations of bitstream reading routines |
| * |
| * \date |
| * 20/11/2002 |
| * |
| * \author AI |
| ************************************************************************* |
| */ |
| |
| /* Includes */ |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include "ih264_typedefs.h" |
| #include "ih264_macros.h" |
| #include "ih264_platform_macros.h" |
| |
| #define INT_IN_BYTES 4 |
| #define INT_IN_BITS 32 |
| |
| /* Based on level 1.2 of baseline profile */ |
| /* 396[MAX_FS] * 128 * 1.5 [ChromaFormatParameter] / sizeof(UWORD32) |
| i.e 396 * 128 * 1.5 / 4 = 19008 */ |
| /* Based on level 3 of main profile */ |
| /* 1620[MAX_FS] * 128 * 1.5 [ChromaFormatParameter] / sizeof(UWORD32) |
| i.e 1620 * 128 * 1.5 / 4= 77760 */ |
| #define SIZE_OF_BUFFER 77760 |
| |
| /* Structure for the ps_bitstrm */ |
| typedef struct |
| { |
| UWORD32 u4_ofst; /* Offset in the buffer for the current bit */ |
| UWORD32 *pu4_buffer; /* Bitstream Buffer */ |
| UWORD32 u4_max_ofst; /* Position of the last bit read in the current buffer */ |
| void * pv_codec_handle; /* For Error Handling */ |
| } dec_bit_stream_t; |
| |
| /* To read the next bit */ |
| UWORD8 ih264d_get_bit_h264(dec_bit_stream_t *); |
| |
| /* To read the next specified number of bits */ |
| UWORD32 ih264d_get_bits_h264(dec_bit_stream_t *, UWORD32); |
| |
| /* To see the next specified number of bits */ |
| UWORD32 ih264d_next_bits_h264(dec_bit_stream_t *, UWORD32); |
| |
| /* To flush a specified number of bits*/ |
| WORD32 ih264d_flush_bits_h264(dec_bit_stream_t *, WORD32); |
| |
| /*! |
| ************************************************************************** |
| * \if Function name : MoreRbspData \endif |
| * |
| * \brief |
| * Determines whether there is more data in RBSP or not. |
| * |
| * \param ps_bitstrm : Pointer to bitstream |
| * |
| * \return |
| * Returns 1 if there is more data in RBSP before rbsp_trailing_bits(). |
| * Otherwise it returns FALSE. |
| ************************************************************************** |
| */ |
| |
| #define MORE_RBSP_DATA(ps_bitstrm) \ |
| (ps_bitstrm->u4_ofst < ps_bitstrm->u4_max_ofst) |
| #define EXCEED_OFFSET(ps_bitstrm) \ |
| (ps_bitstrm->u4_ofst > ps_bitstrm->u4_max_ofst) |
| |
| void GoToByteBoundary(dec_bit_stream_t * ps_bitstrm); |
| UWORD8 ih264d_check_byte_aligned(dec_bit_stream_t * ps_bitstrm); |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of GETBIT: */ |
| /*****************************************************************************/ |
| #define GETBIT(u4_code, u4_offset, pu4_bitstream) \ |
| { \ |
| UWORD32 *pu4_buf = (pu4_bitstream); \ |
| UWORD32 u4_word_off = ((u4_offset) >> 5); \ |
| UWORD32 u4_bit_off = (u4_offset) & 0x1F; \ |
| u4_code = pu4_buf[u4_word_off] << u4_bit_off; \ |
| (u4_offset)++; \ |
| u4_code = (u4_code >> 31); \ |
| } |
| |
| |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of GETBITS: u4_no_bits shall not exceed 32 */ |
| /*****************************************************************************/ |
| #define GETBITS(u4_code, u4_offset, pu4_bitstream, u4_no_bits) \ |
| { \ |
| UWORD32 *pu4_buf = (pu4_bitstream); \ |
| UWORD32 u4_word_off = ((u4_offset) >> 5); \ |
| UWORD32 u4_bit_off = (u4_offset) & 0x1F; \ |
| u4_code = pu4_buf[u4_word_off++] << u4_bit_off; \ |
| \ |
| if(u4_bit_off) \ |
| u4_code |= (pu4_buf[u4_word_off] >> (INT_IN_BITS - u4_bit_off)); \ |
| u4_code = u4_code >> (INT_IN_BITS - u4_no_bits); \ |
| (u4_offset) += u4_no_bits; \ |
| } \ |
| \ |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of NEXTBITS */ |
| /*****************************************************************************/ |
| #define NEXTBITS(u4_word, u4_offset, pu4_bitstream, u4_no_bits) \ |
| { \ |
| UWORD32 *pu4_buf = (pu4_bitstream); \ |
| UWORD32 u4_word_off = ((u4_offset) >> 5); \ |
| UWORD32 u4_bit_off = (u4_offset) & 0x1F; \ |
| u4_word = pu4_buf[u4_word_off++] << u4_bit_off; \ |
| if(u4_bit_off) \ |
| u4_word |= (pu4_buf[u4_word_off] >> (INT_IN_BITS - u4_bit_off)); \ |
| u4_word = u4_word >> (INT_IN_BITS - u4_no_bits); \ |
| } |
| /*****************************************************************************/ |
| /* Define a macro for inlining of NEXTBITS_32 */ |
| /*****************************************************************************/ |
| #define NEXTBITS_32(u4_word, u4_offset, pu4_bitstream) \ |
| { \ |
| UWORD32 *pu4_buf = (pu4_bitstream); \ |
| UWORD32 u4_word_off = ((u4_offset) >> 5); \ |
| UWORD32 u4_bit_off = (u4_offset) & 0x1F; \ |
| \ |
| u4_word = pu4_buf[u4_word_off++] << u4_bit_off; \ |
| if(u4_bit_off) \ |
| u4_word |= (pu4_buf[u4_word_off] >> (INT_IN_BITS - u4_bit_off)); \ |
| } |
| |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of FIND_ONE_IN_STREAM_32 */ |
| /*****************************************************************************/ |
| #define FIND_ONE_IN_STREAM_32(u4_ldz, u4_offset, pu4_bitstream) \ |
| { \ |
| UWORD32 u4_word; \ |
| NEXTBITS_32(u4_word, u4_offset, pu4_bitstream); \ |
| u4_ldz = CLZ(u4_word); \ |
| (u4_offset) += (u4_ldz + 1); \ |
| } |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of FIND_ONE_IN_STREAM_LEN */ |
| /*****************************************************************************/ |
| #define FIND_ONE_IN_STREAM_LEN(u4_ldz, u4_offset, pu4_bitstream, u4_len) \ |
| { \ |
| UWORD32 u4_word; \ |
| NEXTBITS_32(u4_word, u4_offset, pu4_bitstream); \ |
| u4_ldz = CLZ(u4_word); \ |
| if(u4_ldz < u4_len) \ |
| (u4_offset) += (u4_ldz + 1); \ |
| else \ |
| { \ |
| u4_ldz = u4_len; \ |
| (u4_offset) += u4_ldz; \ |
| } \ |
| } |
| |
| /*****************************************************************************/ |
| /* Define a macro for inlining of FLUSHBITS */ |
| /*****************************************************************************/ |
| #define FLUSHBITS(u4_offset, u4_no_bits) \ |
| { \ |
| (u4_offset) += (u4_no_bits); \ |
| } |
| |
| #endif /* _BITSTREAM_H_ */ |