1/*
2 * H263/MPEG4 backend for ffmpeg encoder and decoder
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 * H263+ support.
5 * Copyright (c) 2001 Juan J. Sierralta P
6 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
7 *
8 * This file is part of FFmpeg.
9 *
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
14 *
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25/**
26 * @file
27 * h263/mpeg4 codec.
28 */
29
30//#define DEBUG
31#include <limits.h>
32
33#include "dsputil.h"
34#include "avcodec.h"
35#include "mpegvideo.h"
36#include "h263.h"
37#include "h263data.h"
38#include "mathops.h"
39#include "unary.h"
40#include "flv.h"
41#include "mpeg4video.h"
42
43//#undef NDEBUG
44//#include <assert.h>
45
46uint8_t ff_h263_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
47
48
49void ff_h263_update_motion_val(MpegEncContext * s){
50    const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
51               //FIXME a lot of that is only needed for !low_delay
52    const int wrap = s->b8_stride;
53    const int xy = s->block_index[0];
54
55    s->current_picture.mbskip_table[mb_xy]= s->mb_skipped;
56
57    if(s->mv_type != MV_TYPE_8X8){
58        int motion_x, motion_y;
59        if (s->mb_intra) {
60            motion_x = 0;
61            motion_y = 0;
62        } else if (s->mv_type == MV_TYPE_16X16) {
63            motion_x = s->mv[0][0][0];
64            motion_y = s->mv[0][0][1];
65        } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
66            int i;
67            motion_x = s->mv[0][0][0] + s->mv[0][1][0];
68            motion_y = s->mv[0][0][1] + s->mv[0][1][1];
69            motion_x = (motion_x>>1) | (motion_x&1);
70            for(i=0; i<2; i++){
71                s->p_field_mv_table[i][0][mb_xy][0]= s->mv[0][i][0];
72                s->p_field_mv_table[i][0][mb_xy][1]= s->mv[0][i][1];
73            }
74            s->current_picture.ref_index[0][4*mb_xy    ]=
75            s->current_picture.ref_index[0][4*mb_xy + 1]= s->field_select[0][0];
76            s->current_picture.ref_index[0][4*mb_xy + 2]=
77            s->current_picture.ref_index[0][4*mb_xy + 3]= s->field_select[0][1];
78        }
79
80        /* no update if 8X8 because it has been done during parsing */
81        s->current_picture.motion_val[0][xy][0] = motion_x;
82        s->current_picture.motion_val[0][xy][1] = motion_y;
83        s->current_picture.motion_val[0][xy + 1][0] = motion_x;
84        s->current_picture.motion_val[0][xy + 1][1] = motion_y;
85        s->current_picture.motion_val[0][xy + wrap][0] = motion_x;
86        s->current_picture.motion_val[0][xy + wrap][1] = motion_y;
87        s->current_picture.motion_val[0][xy + 1 + wrap][0] = motion_x;
88        s->current_picture.motion_val[0][xy + 1 + wrap][1] = motion_y;
89    }
90
91    if(s->encoding){ //FIXME encoding MUST be cleaned up
92        if (s->mv_type == MV_TYPE_8X8)
93            s->current_picture.mb_type[mb_xy]= MB_TYPE_L0 | MB_TYPE_8x8;
94        else if(s->mb_intra)
95            s->current_picture.mb_type[mb_xy]= MB_TYPE_INTRA;
96        else
97            s->current_picture.mb_type[mb_xy]= MB_TYPE_L0 | MB_TYPE_16x16;
98    }
99}
100
101int h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr)
102{
103    int x, y, wrap, a, c, pred_dc;
104    int16_t *dc_val;
105
106    /* find prediction */
107    if (n < 4) {
108        x = 2 * s->mb_x + (n & 1);
109        y = 2 * s->mb_y + ((n & 2) >> 1);
110        wrap = s->b8_stride;
111        dc_val = s->dc_val[0];
112    } else {
113        x = s->mb_x;
114        y = s->mb_y;
115        wrap = s->mb_stride;
116        dc_val = s->dc_val[n - 4 + 1];
117    }
118    /* B C
119     * A X
120     */
121    a = dc_val[(x - 1) + (y) * wrap];
122    c = dc_val[(x) + (y - 1) * wrap];
123
124    /* No prediction outside GOB boundary */
125    if(s->first_slice_line && n!=3){
126        if(n!=2) c= 1024;
127        if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
128    }
129    /* just DC prediction */
130    if (a != 1024 && c != 1024)
131        pred_dc = (a + c) >> 1;
132    else if (a != 1024)
133        pred_dc = a;
134    else
135        pred_dc = c;
136
137    /* we assume pred is positive */
138    *dc_val_ptr = &dc_val[x + y * wrap];
139    return pred_dc;
140}
141
142void ff_h263_loop_filter(MpegEncContext * s){
143    int qp_c;
144    const int linesize  = s->linesize;
145    const int uvlinesize= s->uvlinesize;
146    const int xy = s->mb_y * s->mb_stride + s->mb_x;
147    uint8_t *dest_y = s->dest[0];
148    uint8_t *dest_cb= s->dest[1];
149    uint8_t *dest_cr= s->dest[2];
150
151//    if(s->pict_type==FF_B_TYPE && !s->readable) return;
152
153    /*
154       Diag Top
155       Left Center
156    */
157    if(!IS_SKIP(s->current_picture.mb_type[xy])){
158        qp_c= s->qscale;
159        s->dsp.h263_v_loop_filter(dest_y+8*linesize  , linesize, qp_c);
160        s->dsp.h263_v_loop_filter(dest_y+8*linesize+8, linesize, qp_c);
161    }else
162        qp_c= 0;
163
164    if(s->mb_y){
165        int qp_dt, qp_tt, qp_tc;
166
167        if(IS_SKIP(s->current_picture.mb_type[xy-s->mb_stride]))
168            qp_tt=0;
169        else
170            qp_tt= s->current_picture.qscale_table[xy-s->mb_stride];
171
172        if(qp_c)
173            qp_tc= qp_c;
174        else
175            qp_tc= qp_tt;
176
177        if(qp_tc){
178            const int chroma_qp= s->chroma_qscale_table[qp_tc];
179            s->dsp.h263_v_loop_filter(dest_y  ,   linesize, qp_tc);
180            s->dsp.h263_v_loop_filter(dest_y+8,   linesize, qp_tc);
181
182            s->dsp.h263_v_loop_filter(dest_cb , uvlinesize, chroma_qp);
183            s->dsp.h263_v_loop_filter(dest_cr , uvlinesize, chroma_qp);
184        }
185
186        if(qp_tt)
187            s->dsp.h263_h_loop_filter(dest_y-8*linesize+8  ,   linesize, qp_tt);
188
189        if(s->mb_x){
190            if(qp_tt || IS_SKIP(s->current_picture.mb_type[xy-1-s->mb_stride]))
191                qp_dt= qp_tt;
192            else
193                qp_dt= s->current_picture.qscale_table[xy-1-s->mb_stride];
194
195            if(qp_dt){
196                const int chroma_qp= s->chroma_qscale_table[qp_dt];
197                s->dsp.h263_h_loop_filter(dest_y -8*linesize  ,   linesize, qp_dt);
198                s->dsp.h263_h_loop_filter(dest_cb-8*uvlinesize, uvlinesize, chroma_qp);
199                s->dsp.h263_h_loop_filter(dest_cr-8*uvlinesize, uvlinesize, chroma_qp);
200            }
201        }
202    }
203
204    if(qp_c){
205        s->dsp.h263_h_loop_filter(dest_y +8,   linesize, qp_c);
206        if(s->mb_y + 1 == s->mb_height)
207            s->dsp.h263_h_loop_filter(dest_y+8*linesize+8,   linesize, qp_c);
208    }
209
210    if(s->mb_x){
211        int qp_lc;
212        if(qp_c || IS_SKIP(s->current_picture.mb_type[xy-1]))
213            qp_lc= qp_c;
214        else
215            qp_lc= s->current_picture.qscale_table[xy-1];
216
217        if(qp_lc){
218            s->dsp.h263_h_loop_filter(dest_y,   linesize, qp_lc);
219            if(s->mb_y + 1 == s->mb_height){
220                const int chroma_qp= s->chroma_qscale_table[qp_lc];
221                s->dsp.h263_h_loop_filter(dest_y +8*  linesize,   linesize, qp_lc);
222                s->dsp.h263_h_loop_filter(dest_cb             , uvlinesize, chroma_qp);
223                s->dsp.h263_h_loop_filter(dest_cr             , uvlinesize, chroma_qp);
224            }
225        }
226    }
227}
228
229void h263_pred_acdc(MpegEncContext * s, DCTELEM *block, int n)
230{
231    int x, y, wrap, a, c, pred_dc, scale, i;
232    int16_t *dc_val, *ac_val, *ac_val1;
233
234    /* find prediction */
235    if (n < 4) {
236        x = 2 * s->mb_x + (n & 1);
237        y = 2 * s->mb_y + (n>> 1);
238        wrap = s->b8_stride;
239        dc_val = s->dc_val[0];
240        ac_val = s->ac_val[0][0];
241        scale = s->y_dc_scale;
242    } else {
243        x = s->mb_x;
244        y = s->mb_y;
245        wrap = s->mb_stride;
246        dc_val = s->dc_val[n - 4 + 1];
247        ac_val = s->ac_val[n - 4 + 1][0];
248        scale = s->c_dc_scale;
249    }
250
251    ac_val += ((y) * wrap + (x)) * 16;
252    ac_val1 = ac_val;
253
254    /* B C
255     * A X
256     */
257    a = dc_val[(x - 1) + (y) * wrap];
258    c = dc_val[(x) + (y - 1) * wrap];
259
260    /* No prediction outside GOB boundary */
261    if(s->first_slice_line && n!=3){
262        if(n!=2) c= 1024;
263        if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
264    }
265
266    if (s->ac_pred) {
267        pred_dc = 1024;
268        if (s->h263_aic_dir) {
269            /* left prediction */
270            if (a != 1024) {
271                ac_val -= 16;
272                for(i=1;i<8;i++) {
273                    block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
274                }
275                pred_dc = a;
276            }
277        } else {
278            /* top prediction */
279            if (c != 1024) {
280                ac_val -= 16 * wrap;
281                for(i=1;i<8;i++) {
282                    block[s->dsp.idct_permutation[i   ]] += ac_val[i + 8];
283                }
284                pred_dc = c;
285            }
286        }
287    } else {
288        /* just DC prediction */
289        if (a != 1024 && c != 1024)
290            pred_dc = (a + c) >> 1;
291        else if (a != 1024)
292            pred_dc = a;
293        else
294            pred_dc = c;
295    }
296
297    /* we assume pred is positive */
298    block[0]=block[0]*scale + pred_dc;
299
300    if (block[0] < 0)
301        block[0] = 0;
302    else
303        block[0] |= 1;
304
305    /* Update AC/DC tables */
306    dc_val[(x) + (y) * wrap] = block[0];
307
308    /* left copy */
309    for(i=1;i<8;i++)
310        ac_val1[i    ] = block[s->dsp.idct_permutation[i<<3]];
311    /* top copy */
312    for(i=1;i<8;i++)
313        ac_val1[8 + i] = block[s->dsp.idct_permutation[i   ]];
314}
315
316int16_t *h263_pred_motion(MpegEncContext * s, int block, int dir,
317                        int *px, int *py)
318{
319    int wrap;
320    int16_t *A, *B, *C, (*mot_val)[2];
321    static const int off[4]= {2, 1, 1, -1};
322
323    wrap = s->b8_stride;
324    mot_val = s->current_picture.motion_val[dir] + s->block_index[block];
325
326    A = mot_val[ - 1];
327    /* special case for first (slice) line */
328    if (s->first_slice_line && block<3) {
329        // we can't just change some MVs to simulate that as we need them for the B frames (and ME)
330        // and if we ever support non rectangular objects than we need to do a few ifs here anyway :(
331        if(block==0){ //most common case
332            if(s->mb_x  == s->resync_mb_x){ //rare
333                *px= *py = 0;
334            }else if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
335                C = mot_val[off[block] - wrap];
336                if(s->mb_x==0){
337                    *px = C[0];
338                    *py = C[1];
339                }else{
340                    *px = mid_pred(A[0], 0, C[0]);
341                    *py = mid_pred(A[1], 0, C[1]);
342                }
343            }else{
344                *px = A[0];
345                *py = A[1];
346            }
347        }else if(block==1){
348            if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
349                C = mot_val[off[block] - wrap];
350                *px = mid_pred(A[0], 0, C[0]);
351                *py = mid_pred(A[1], 0, C[1]);
352            }else{
353                *px = A[0];
354                *py = A[1];
355            }
356        }else{ /* block==2*/
357            B = mot_val[ - wrap];
358            C = mot_val[off[block] - wrap];
359            if(s->mb_x == s->resync_mb_x) //rare
360                A[0]=A[1]=0;
361
362            *px = mid_pred(A[0], B[0], C[0]);
363            *py = mid_pred(A[1], B[1], C[1]);
364        }
365    } else {
366        B = mot_val[ - wrap];
367        C = mot_val[off[block] - wrap];
368        *px = mid_pred(A[0], B[0], C[0]);
369        *py = mid_pred(A[1], B[1], C[1]);
370    }
371    return *mot_val;
372}
373
374
375/**
376 * Get the GOB height based on picture height.
377 */
378int ff_h263_get_gob_height(MpegEncContext *s){
379    if (s->height <= 400)
380        return 1;
381    else if (s->height <= 800)
382        return  2;
383    else
384        return 4;
385}
386