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/******************************************************************************
*
* 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
*/
#include "iv_datatypedef.h"
#include "impeg2_defs.h"
#include "impeg2_globals.h"
#include "impeg2_platform_macros.h"
#include "impeg2_inter_pred.h"
#include "impeg2_idct.h"
#include "impeg2_mem_func.h"
#include "impeg2_format_conv.h"
#include "impeg2_disp_mgr.h"
#include "impeg2_buf_mgr.h"
#include "impeg2d.h"
#include "impeg2d_bitstream.h"
#include "impeg2d_structs.h"
#include "impeg2d_vld.h"
#include "impeg2d_vld_tables.h"
#define BLK_SIZE 8
#define LUMA_BLK_SIZE (2 * (BLK_SIZE))
#define CHROMA_BLK_SIZE (BLK_SIZE)
/*****************************************************************************/
/* */
/* Function Name : impeg2d_get_luma_dc_diff */
/* */
/* Description : Decode the DC differential value from the bitstream for */
/* luma block */
/* */
/* Inputs : stream - Input stream */
/* */
/* Globals : None */
/* */
/* Processing : Decode the vlc for dc_diff */
/* */
/* Outputs : dc_diff - dc differential used in dc prediction */
/* */
/* Returns : dc_diff - dc differential used in dc prediction */
/* */
/* Issues : None */
/* */
/* Revision History: */
/* */
/* DD MM YYYY Author(s) Changes */
/* 14 09 2005 Harish M First Version */
/* */
/*****************************************************************************/
WORD16 impeg2d_get_luma_dc_diff(stream_t *ps_stream)
{
UWORD16 u2_dc_size;
WORD16 i2_dc_diff;
u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[0],
MPEG2_DCT_DC_LUMA_SIZE_LEN) +
MPEG2_DCT_DC_SIZE_OFFSET;
if (u2_dc_size != 0)
{
i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
i2_dc_diff -= (1 << u2_dc_size) - 1;
}
else
{
i2_dc_diff = 0;
}
return i2_dc_diff;
}
/*****************************************************************************/
/* */
/* Function Name : impeg2d_get_chroma_dc_diff */
/* */
/* Description : Decode the DC differential value from the bitstream for */
/* chroma block */
/* */
/* Inputs : stream - Input stream */
/* */
/* Globals : None */
/* */
/* Processing : Decode the vlc for dc_diff */
/* */
/* Outputs : dc_diff - dc differential used in dc prediction */
/* */
/* Returns : dc_diff - dc differential used in dc prediction */
/* */
/* Issues : None */
/* */
/* Revision History: */
/* */
/* DD MM YYYY Author(s) Changes */
/* 14 09 2005 Harish M First Version */
/* */
/*****************************************************************************/
WORD16 impeg2d_get_chroma_dc_diff(stream_t *ps_stream)
{
UWORD16 u2_dc_size;
WORD16 i2_dc_diff;
u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[1],
MPEG2_DCT_DC_CHROMA_SIZE_LEN) +
MPEG2_DCT_DC_SIZE_OFFSET;
if (u2_dc_size != 0)
{
i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
i2_dc_diff -= (1 << u2_dc_size) - 1;
}
else
{
i2_dc_diff = 0;
}
return i2_dc_diff;
}
/*******************************************************************************
* Function Name : impeg2d_dec_d_slice
*
* Description : Decodes I slice
*
* Arguments :
* dec : Decoder state
*
* Values Returned : None
*******************************************************************************/
IMPEG2D_ERROR_CODES_T impeg2d_dec_d_slice(dec_state_t *ps_dec)
{
UWORD32 i;
yuv_buf_t *ps_cur_frm_buf = &ps_dec->s_cur_frm_buf;
stream_t *ps_stream = &ps_dec->s_bit_stream;
UWORD8 *pu1_vld_buf;
WORD16 i2_dc_diff;
UWORD32 u4_frame_width = ps_dec->u2_frame_width;
UWORD32 u4_frm_offset = 0;
if(ps_dec->u2_picture_structure != FRAME_PICTURE)
{
u4_frame_width <<= 1;
if(ps_dec->u2_picture_structure == BOTTOM_FIELD)
{
u4_frm_offset = ps_dec->u2_frame_width;
}
}
do
{
UWORD32 u4_x_offset, u4_y_offset;
UWORD32 u4_blk_pos;
WORD16 i2_dc_val;
UWORD32 u4_dst_x_offset = u4_frm_offset + (ps_dec->u2_mb_x << 4);
UWORD32 u4_dst_y_offset = (ps_dec->u2_mb_y << 4) * u4_frame_width;
UWORD8 *pu1_vld_buf8 = ps_cur_frm_buf->pu1_y + u4_dst_x_offset + u4_dst_y_offset;
UWORD32 u4_dst_wd = u4_frame_width;
/*------------------------------------------------------------------*/
/* Discard the Macroblock stuffing in case of MPEG-1 stream */
/*------------------------------------------------------------------*/
while(impeg2d_bit_stream_nxt(ps_stream,MB_STUFFING_CODE_LEN) == MB_STUFFING_CODE)
impeg2d_bit_stream_flush(ps_stream,MB_STUFFING_CODE_LEN);
/*------------------------------------------------------------------*/
/* Flush 2 bits from bitstream [MB_Type and MacroBlockAddrIncrement]*/
/*------------------------------------------------------------------*/
impeg2d_bit_stream_flush(ps_stream,1);
if(impeg2d_bit_stream_get(ps_stream, 1) != 0x01)
{
/* Ignore and continue decoding. */
}
/* Process LUMA blocks of the MB */
for(i = 0; i < NUM_LUMA_BLKS; ++i)
{
u4_x_offset = gai2_impeg2_blk_x_off[i];
u4_y_offset = gai2_impeg2_blk_y_off_frm[i] ;
u4_blk_pos = (u4_y_offset * u4_dst_wd) + u4_x_offset;
pu1_vld_buf = pu1_vld_buf8 + u4_blk_pos;
i2_dc_diff = impeg2d_get_luma_dc_diff(ps_stream);
i2_dc_val = ps_dec->u2_def_dc_pred[Y_LUMA] + i2_dc_diff;
ps_dec->u2_def_dc_pred[Y_LUMA] = i2_dc_val;
i2_dc_val = CLIP_U8(i2_dc_val);
ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
}
/* Process U block of the MB */
u4_dst_x_offset >>= 1;
u4_dst_y_offset >>= 2;
u4_dst_wd >>= 1;
pu1_vld_buf = ps_cur_frm_buf->pu1_u + u4_dst_x_offset + u4_dst_y_offset;
i2_dc_diff = impeg2d_get_chroma_dc_diff(ps_stream);
i2_dc_val = ps_dec->u2_def_dc_pred[U_CHROMA] + i2_dc_diff;
ps_dec->u2_def_dc_pred[U_CHROMA] = i2_dc_val;
i2_dc_val = CLIP_U8(i2_dc_val);
ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
/* Process V block of the MB */
pu1_vld_buf = ps_cur_frm_buf->pu1_v + u4_dst_x_offset + u4_dst_y_offset;
i2_dc_diff = impeg2d_get_chroma_dc_diff(ps_stream);
i2_dc_val = ps_dec->u2_def_dc_pred[V_CHROMA] + i2_dc_diff;
ps_dec->u2_def_dc_pred[V_CHROMA] = i2_dc_val;
i2_dc_val = CLIP_U8(i2_dc_val);
ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
/* Common MB processing Steps */
ps_dec->u2_num_mbs_left--;
ps_dec->u2_mb_x++;
if(ps_dec->s_bit_stream.u4_offset > ps_dec->s_bit_stream.u4_max_offset)
{
return IMPEG2D_BITSTREAM_BUFF_EXCEEDED_ERR;
}
else if ((ps_dec->u2_mb_x == ps_dec->u2_num_horiz_mb) && ((ps_dec->s_bit_stream.u4_offset + START_CODE_PREFIX_LEN) < ps_dec->s_bit_stream.u4_max_offset))
{
ps_dec->u2_mb_x = 0;
ps_dec->u2_mb_y++;
}
/* Flush end of macro block */
impeg2d_bit_stream_flush(ps_stream,1);
}
while(ps_dec->u2_num_mbs_left != 0 && impeg2d_bit_stream_nxt(&ps_dec->s_bit_stream,23) != 0x0);
return (IMPEG2D_ERROR_CODES_T)IVD_ERROR_NONE;
}/* End of impeg2d_dec_d_slice() */
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