1/******************************************************************************
2 *
3 * Copyright (C) 2015 The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 *****************************************************************************
18 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19*/
20
21#include "iv_datatypedef.h"
22#include "impeg2_defs.h"
23#include "impeg2_globals.h"
24#include "impeg2_platform_macros.h"
25#include "impeg2_inter_pred.h"
26#include "impeg2_idct.h"
27#include "impeg2_mem_func.h"
28#include "impeg2_format_conv.h"
29#include "impeg2_disp_mgr.h"
30#include "impeg2_buf_mgr.h"
31
32#include "impeg2d.h"
33#include "impeg2d_bitstream.h"
34#include "impeg2d_structs.h"
35#include "impeg2d_vld.h"
36#include "impeg2d_vld_tables.h"
37
38#define BLK_SIZE 8
39#define LUMA_BLK_SIZE (2 * (BLK_SIZE))
40#define CHROMA_BLK_SIZE (BLK_SIZE)
41/*****************************************************************************/
42/*                                                                           */
43/*  Function Name : impeg2d_get_luma_dc_diff                                         */
44/*                                                                           */
45/*  Description   : Decode the DC differential value from the bitstream for  */
46/*                  luma block                                               */
47/*                                                                           */
48/*  Inputs        : stream - Input stream                                    */
49/*                                                                           */
50/*  Globals       : None                                                     */
51/*                                                                           */
52/*  Processing    : Decode the vlc for dc_diff                               */
53/*                                                                           */
54/*  Outputs       : dc_diff - dc differential used in dc prediction          */
55/*                                                                           */
56/*  Returns       : dc_diff - dc differential used in dc prediction          */
57/*                                                                           */
58/*  Issues        : None                                                     */
59/*                                                                           */
60/*  Revision History:                                                        */
61/*                                                                           */
62/*         DD MM YYYY   Author(s)       Changes                              */
63/*         14 09 2005   Harish M        First Version                        */
64/*                                                                           */
65/*****************************************************************************/
66WORD16  impeg2d_get_luma_dc_diff(stream_t *ps_stream)
67{
68    UWORD16 u2_dc_size;
69    WORD16  i2_dc_diff;
70
71    u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[0],
72                        MPEG2_DCT_DC_LUMA_SIZE_LEN) +
73                        MPEG2_DCT_DC_SIZE_OFFSET;
74    if (u2_dc_size != 0)
75    {
76        i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
77        if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
78            i2_dc_diff -= (1 << u2_dc_size) - 1;
79    }
80    else
81    {
82        i2_dc_diff = 0;
83    }
84    return i2_dc_diff;
85}
86
87/*****************************************************************************/
88/*                                                                           */
89/*  Function Name : impeg2d_get_chroma_dc_diff                                       */
90/*                                                                           */
91/*  Description   : Decode the DC differential value from the bitstream for  */
92/*                  chroma block                                             */
93/*                                                                           */
94/*  Inputs        : stream - Input stream                                    */
95/*                                                                           */
96/*  Globals       : None                                                     */
97/*                                                                           */
98/*  Processing    : Decode the vlc for dc_diff                               */
99/*                                                                           */
100/*  Outputs       : dc_diff - dc differential used in dc prediction          */
101/*                                                                           */
102/*  Returns       : dc_diff - dc differential used in dc prediction          */
103/*                                                                           */
104/*  Issues        : None                                                     */
105/*                                                                           */
106/*  Revision History:                                                        */
107/*                                                                           */
108/*         DD MM YYYY   Author(s)       Changes                              */
109/*         14 09 2005   Harish M        First Version                        */
110/*                                                                           */
111/*****************************************************************************/
112WORD16  impeg2d_get_chroma_dc_diff(stream_t *ps_stream)
113{
114    UWORD16 u2_dc_size;
115    WORD16  i2_dc_diff;
116    u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[1],
117                        MPEG2_DCT_DC_CHROMA_SIZE_LEN) +
118                        MPEG2_DCT_DC_SIZE_OFFSET;
119    if (u2_dc_size != 0)
120    {
121        i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
122        if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
123            i2_dc_diff -= (1 << u2_dc_size) - 1;
124    }
125    else
126    {
127        i2_dc_diff = 0;
128    }
129    return i2_dc_diff;
130}
131/*******************************************************************************
132*  Function Name   : impeg2d_dec_d_slice
133*
134*  Description     : Decodes I slice
135*
136*  Arguments       :
137*  dec             : Decoder state
138*
139*  Values Returned : None
140*******************************************************************************/
141IMPEG2D_ERROR_CODES_T impeg2d_dec_d_slice(dec_state_t *ps_dec)
142{
143    UWORD32 i;
144    yuv_buf_t *ps_cur_frm_buf  = &ps_dec->s_cur_frm_buf;
145
146    stream_t   *ps_stream       = &ps_dec->s_bit_stream;
147    UWORD8   *pu1_vld_buf;
148
149    WORD16 i2_dc_diff;
150    UWORD32 u4_frame_width = ps_dec->u2_frame_width;
151    UWORD32 u4_frm_offset = 0;
152    if(ps_dec->u2_picture_structure != FRAME_PICTURE)
153    {
154        u4_frame_width <<= 1;
155        if(ps_dec->u2_picture_structure == BOTTOM_FIELD)
156        {
157            u4_frm_offset = ps_dec->u2_frame_width;
158        }
159    }
160
161    do
162    {
163
164        UWORD32 u4_x_offset, u4_y_offset;
165        UWORD32 u4_blk_pos;
166        WORD16 i2_dc_val;
167
168        UWORD32 u4_dst_x_offset     = u4_frm_offset + (ps_dec->u2_mb_x << 4);
169        UWORD32 u4_dst_y_offset     = (ps_dec->u2_mb_y << 4) * u4_frame_width;
170        UWORD8 *pu1_vld_buf8        = ps_cur_frm_buf->pu1_y + u4_dst_x_offset + u4_dst_y_offset;
171        UWORD32 u4_dst_wd           = u4_frame_width;
172        /*------------------------------------------------------------------*/
173        /* Discard the Macroblock stuffing in case of MPEG-1 stream         */
174        /*------------------------------------------------------------------*/
175        while(impeg2d_bit_stream_nxt(ps_stream,MB_STUFFING_CODE_LEN) == MB_STUFFING_CODE &&
176                ps_stream->u4_offset < ps_stream->u4_max_offset)
177            impeg2d_bit_stream_flush(ps_stream,MB_STUFFING_CODE_LEN);
178
179        /*------------------------------------------------------------------*/
180        /* Flush 2 bits from bitstream [MB_Type and MacroBlockAddrIncrement]*/
181        /*------------------------------------------------------------------*/
182        impeg2d_bit_stream_flush(ps_stream,1);
183
184        if(impeg2d_bit_stream_get(ps_stream, 1) != 0x01)
185        {
186            /* Ignore and continue decoding. */
187        }
188
189        /* Process LUMA blocks of the MB */
190        for(i = 0; i < NUM_LUMA_BLKS; ++i)
191        {
192
193            u4_x_offset    = gai2_impeg2_blk_x_off[i];
194            u4_y_offset    = gai2_impeg2_blk_y_off_frm[i] ;
195            u4_blk_pos     = (u4_y_offset * u4_dst_wd) + u4_x_offset;
196            pu1_vld_buf     = pu1_vld_buf8 + u4_blk_pos;
197
198            i2_dc_diff = impeg2d_get_luma_dc_diff(ps_stream);
199            i2_dc_val = ps_dec->u2_def_dc_pred[Y_LUMA] + i2_dc_diff;
200            ps_dec->u2_def_dc_pred[Y_LUMA] = i2_dc_val;
201            i2_dc_val = CLIP_U8(i2_dc_val);
202
203            ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
204        }
205
206
207
208        /* Process U block of the MB */
209
210        u4_dst_x_offset                >>= 1;
211        u4_dst_y_offset                >>= 2;
212        u4_dst_wd                      >>= 1;
213        pu1_vld_buf                     = ps_cur_frm_buf->pu1_u + u4_dst_x_offset + u4_dst_y_offset;
214        i2_dc_diff                     = impeg2d_get_chroma_dc_diff(ps_stream);
215        i2_dc_val                      = ps_dec->u2_def_dc_pred[U_CHROMA] + i2_dc_diff;
216        ps_dec->u2_def_dc_pred[U_CHROMA]    = i2_dc_val;
217        i2_dc_val = CLIP_U8(i2_dc_val);
218        ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
219
220
221        /* Process V block of the MB */
222
223        pu1_vld_buf                     = ps_cur_frm_buf->pu1_v + u4_dst_x_offset + u4_dst_y_offset;
224        i2_dc_diff                     = impeg2d_get_chroma_dc_diff(ps_stream);
225        i2_dc_val                      = ps_dec->u2_def_dc_pred[V_CHROMA] + i2_dc_diff;
226        ps_dec->u2_def_dc_pred[V_CHROMA]    = i2_dc_val;
227        i2_dc_val = CLIP_U8(i2_dc_val);
228        ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
229
230        /* Common MB processing Steps */
231
232
233        ps_dec->u2_num_mbs_left--;
234        ps_dec->u2_mb_x++;
235
236        if(ps_dec->s_bit_stream.u4_offset > ps_dec->s_bit_stream.u4_max_offset)
237        {
238            return IMPEG2D_BITSTREAM_BUFF_EXCEEDED_ERR;
239        }
240        else if (ps_dec->u2_mb_x == ps_dec->u2_num_horiz_mb)
241        {
242            ps_dec->u2_mb_x = 0;
243            ps_dec->u2_mb_y++;
244
245        }
246
247        /* Flush end of macro block */
248        impeg2d_bit_stream_flush(ps_stream,1);
249    }
250    while(ps_dec->u2_num_mbs_left != 0 && impeg2d_bit_stream_nxt(&ps_dec->s_bit_stream,23) != 0x0);
251    return (IMPEG2D_ERROR_CODES_T)IVD_ERROR_NONE;
252}/* End of impeg2d_dec_d_slice() */
253