xref: /third_party/ffmpeg/libavcodec/vc1_pred.c (revision cabdff1a)
1/*
2 * VC-1 and WMV3 decoder
3 * Copyright (c) 2011 Mashiat Sarker Shakkhar
4 * Copyright (c) 2006-2007 Konstantin Shishkov
5 * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24/**
25 * @file
26 * VC-1 and WMV3 block decoding routines
27 */
28
29#include "mathops.h"
30#include "mpegutils.h"
31#include "mpegvideo.h"
32#include "vc1.h"
33#include "vc1_pred.h"
34#include "vc1data.h"
35
36static av_always_inline int scaleforsame_x(VC1Context *v, int n /* MV */, int dir)
37{
38    int scaledvalue, refdist;
39    int scalesame1, scalesame2;
40    int scalezone1_x, zone1offset_x;
41    int table_index = dir ^ v->second_field;
42
43    if (v->s.pict_type != AV_PICTURE_TYPE_B)
44        refdist = v->refdist;
45    else
46        refdist = dir ? v->brfd : v->frfd;
47    if (refdist > 3)
48        refdist = 3;
49    scalesame1    = ff_vc1_field_mvpred_scales[table_index][1][refdist];
50    scalesame2    = ff_vc1_field_mvpred_scales[table_index][2][refdist];
51    scalezone1_x  = ff_vc1_field_mvpred_scales[table_index][3][refdist];
52    zone1offset_x = ff_vc1_field_mvpred_scales[table_index][5][refdist];
53
54    if (FFABS(n) > 255)
55        scaledvalue = n;
56    else {
57        if (FFABS(n) < scalezone1_x)
58            scaledvalue = (n * scalesame1) >> 8;
59        else {
60            if (n < 0)
61                scaledvalue = ((n * scalesame2) >> 8) - zone1offset_x;
62            else
63                scaledvalue = ((n * scalesame2) >> 8) + zone1offset_x;
64        }
65    }
66    return av_clip(scaledvalue, -v->range_x, v->range_x - 1);
67}
68
69static av_always_inline int scaleforsame_y(VC1Context *v, int i, int n /* MV */, int dir)
70{
71    int scaledvalue, refdist;
72    int scalesame1, scalesame2;
73    int scalezone1_y, zone1offset_y;
74    int table_index = dir ^ v->second_field;
75
76    if (v->s.pict_type != AV_PICTURE_TYPE_B)
77        refdist = v->refdist;
78    else
79        refdist = dir ? v->brfd : v->frfd;
80    if (refdist > 3)
81        refdist = 3;
82    scalesame1    = ff_vc1_field_mvpred_scales[table_index][1][refdist];
83    scalesame2    = ff_vc1_field_mvpred_scales[table_index][2][refdist];
84    scalezone1_y  = ff_vc1_field_mvpred_scales[table_index][4][refdist];
85    zone1offset_y = ff_vc1_field_mvpred_scales[table_index][6][refdist];
86
87    if (FFABS(n) > 63)
88        scaledvalue = n;
89    else {
90        if (FFABS(n) < scalezone1_y)
91            scaledvalue = (n * scalesame1) >> 8;
92        else {
93            if (n < 0)
94                scaledvalue = ((n * scalesame2) >> 8) - zone1offset_y;
95            else
96                scaledvalue = ((n * scalesame2) >> 8) + zone1offset_y;
97        }
98    }
99
100    if (v->cur_field_type && !v->ref_field_type[dir])
101        return av_clip(scaledvalue, -v->range_y / 2 + 1, v->range_y / 2);
102    else
103        return av_clip(scaledvalue, -v->range_y / 2, v->range_y / 2 - 1);
104}
105
106static av_always_inline int scaleforopp_x(VC1Context *v, int n /* MV */)
107{
108    int scalezone1_x, zone1offset_x;
109    int scaleopp1, scaleopp2, brfd;
110    int scaledvalue;
111
112    brfd = FFMIN(v->brfd, 3);
113    scalezone1_x  = ff_vc1_b_field_mvpred_scales[3][brfd];
114    zone1offset_x = ff_vc1_b_field_mvpred_scales[5][brfd];
115    scaleopp1     = ff_vc1_b_field_mvpred_scales[1][brfd];
116    scaleopp2     = ff_vc1_b_field_mvpred_scales[2][brfd];
117
118    if (FFABS(n) > 255)
119        scaledvalue = n;
120    else {
121        if (FFABS(n) < scalezone1_x)
122            scaledvalue = (n * scaleopp1) >> 8;
123        else {
124            if (n < 0)
125                scaledvalue = ((n * scaleopp2) >> 8) - zone1offset_x;
126            else
127                scaledvalue = ((n * scaleopp2) >> 8) + zone1offset_x;
128        }
129    }
130    return av_clip(scaledvalue, -v->range_x, v->range_x - 1);
131}
132
133static av_always_inline int scaleforopp_y(VC1Context *v, int n /* MV */, int dir)
134{
135    int scalezone1_y, zone1offset_y;
136    int scaleopp1, scaleopp2, brfd;
137    int scaledvalue;
138
139    brfd = FFMIN(v->brfd, 3);
140    scalezone1_y  = ff_vc1_b_field_mvpred_scales[4][brfd];
141    zone1offset_y = ff_vc1_b_field_mvpred_scales[6][brfd];
142    scaleopp1     = ff_vc1_b_field_mvpred_scales[1][brfd];
143    scaleopp2     = ff_vc1_b_field_mvpred_scales[2][brfd];
144
145    if (FFABS(n) > 63)
146        scaledvalue = n;
147    else {
148        if (FFABS(n) < scalezone1_y)
149            scaledvalue = (n * scaleopp1) >> 8;
150        else {
151            if (n < 0)
152                scaledvalue = ((n * scaleopp2) >> 8) - zone1offset_y;
153            else
154                scaledvalue = ((n * scaleopp2) >> 8) + zone1offset_y;
155        }
156    }
157    if (v->cur_field_type && !v->ref_field_type[dir]) {
158        return av_clip(scaledvalue, -v->range_y / 2 + 1, v->range_y / 2);
159    } else {
160        return av_clip(scaledvalue, -v->range_y / 2, v->range_y / 2 - 1);
161    }
162}
163
164static av_always_inline int scaleforsame(VC1Context *v, int i, int n /* MV */,
165                                         int dim, int dir)
166{
167    int brfd, scalesame;
168    int hpel = 1 - v->s.quarter_sample;
169
170    n >>= hpel;
171    if (v->s.pict_type != AV_PICTURE_TYPE_B || v->second_field || !dir) {
172        if (dim)
173            n = scaleforsame_y(v, i, n, dir) * (1 << hpel);
174        else
175            n = scaleforsame_x(v, n, dir) * (1 << hpel);
176        return n;
177    }
178    brfd      = FFMIN(v->brfd, 3);
179    scalesame = ff_vc1_b_field_mvpred_scales[0][brfd];
180
181    n = (n * scalesame >> 8) * (1 << hpel);
182    return n;
183}
184
185static av_always_inline int scaleforopp(VC1Context *v, int n /* MV */,
186                                        int dim, int dir)
187{
188    int refdist, scaleopp;
189    int hpel = 1 - v->s.quarter_sample;
190
191    n >>= hpel;
192    if (v->s.pict_type == AV_PICTURE_TYPE_B && !v->second_field && dir == 1) {
193        if (dim)
194            n = scaleforopp_y(v, n, dir) * (1 << hpel);
195        else
196            n = scaleforopp_x(v, n)      * (1 << hpel);
197        return n;
198    }
199    if (v->s.pict_type != AV_PICTURE_TYPE_B)
200        refdist = v->refdist;
201    else
202        refdist = dir ? v->brfd : v->frfd;
203    refdist = FFMIN(refdist, 3);
204    scaleopp = ff_vc1_field_mvpred_scales[dir ^ v->second_field][0][refdist];
205
206    n = (n * scaleopp >> 8) * (1 << hpel);
207    return n;
208}
209
210/** Predict and set motion vector
211 */
212void ff_vc1_pred_mv(VC1Context *v, int n, int dmv_x, int dmv_y,
213                    int mv1, int r_x, int r_y, uint8_t* is_intra,
214                    int pred_flag, int dir)
215{
216    MpegEncContext *s = &v->s;
217    int xy, wrap, off = 0;
218    int16_t *A, *B, *C;
219    int px, py;
220    int sum;
221    int mixedmv_pic, num_samefield = 0, num_oppfield = 0;
222    int opposite, a_f, b_f, c_f;
223    int16_t field_predA[2];
224    int16_t field_predB[2];
225    int16_t field_predC[2];
226    int a_valid, b_valid, c_valid;
227    int hybridmv_thresh, y_bias = 0;
228
229    if (v->mv_mode == MV_PMODE_MIXED_MV ||
230        ((v->mv_mode == MV_PMODE_INTENSITY_COMP) && (v->mv_mode2 == MV_PMODE_MIXED_MV)))
231        mixedmv_pic = 1;
232    else
233        mixedmv_pic = 0;
234    /* scale MV difference to be quad-pel */
235    if (!s->quarter_sample) {
236        dmv_x *= 2;
237        dmv_y *= 2;
238    }
239
240    wrap = s->b8_stride;
241    xy   = s->block_index[n];
242
243    if (s->mb_intra) {
244        s->mv[0][n][0] = s->current_picture.motion_val[0][xy + v->blocks_off][0] = 0;
245        s->mv[0][n][1] = s->current_picture.motion_val[0][xy + v->blocks_off][1] = 0;
246        s->current_picture.motion_val[1][xy + v->blocks_off][0] = 0;
247        s->current_picture.motion_val[1][xy + v->blocks_off][1] = 0;
248        if (mv1) { /* duplicate motion data for 1-MV block */
249            s->current_picture.motion_val[0][xy + 1 + v->blocks_off][0]        = 0;
250            s->current_picture.motion_val[0][xy + 1 + v->blocks_off][1]        = 0;
251            s->current_picture.motion_val[0][xy + wrap + v->blocks_off][0]     = 0;
252            s->current_picture.motion_val[0][xy + wrap + v->blocks_off][1]     = 0;
253            s->current_picture.motion_val[0][xy + wrap + 1 + v->blocks_off][0] = 0;
254            s->current_picture.motion_val[0][xy + wrap + 1 + v->blocks_off][1] = 0;
255            v->luma_mv[s->mb_x][0] = v->luma_mv[s->mb_x][1] = 0;
256            s->current_picture.motion_val[1][xy + 1 + v->blocks_off][0]        = 0;
257            s->current_picture.motion_val[1][xy + 1 + v->blocks_off][1]        = 0;
258            s->current_picture.motion_val[1][xy + wrap + v->blocks_off][0]     = 0;
259            s->current_picture.motion_val[1][xy + wrap + v->blocks_off][1]     = 0;
260            s->current_picture.motion_val[1][xy + wrap + 1 + v->blocks_off][0] = 0;
261            s->current_picture.motion_val[1][xy + wrap + 1 + v->blocks_off][1] = 0;
262        }
263        return;
264    }
265
266    a_valid = !s->first_slice_line || (n == 2 || n == 3);
267    b_valid = a_valid;
268    c_valid = s->mb_x || (n == 1 || n == 3);
269    if (mv1) {
270        if (v->field_mode && mixedmv_pic)
271            off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;
272        else
273            off = (s->mb_x == (s->mb_width - 1)) ? -1 : 2;
274        b_valid = b_valid && s->mb_width > 1;
275    } else {
276        //in 4-MV mode different blocks have different B predictor position
277        switch (n) {
278        case 0:
279            if (v->res_rtm_flag)
280                off = s->mb_x ? -1 : 1;
281            else
282                off = s->mb_x ? -1 : 2 * s->mb_width - wrap - 1;
283            break;
284        case 1:
285            off = (s->mb_x == (s->mb_width - 1)) ? -1 : 1;
286            break;
287        case 2:
288            off = 1;
289            break;
290        case 3:
291            off = -1;
292        }
293        if (v->field_mode && s->mb_width == 1)
294            b_valid = b_valid && c_valid;
295    }
296
297    if (v->field_mode) {
298        a_valid = a_valid && !is_intra[xy - wrap];
299        b_valid = b_valid && !is_intra[xy - wrap + off];
300        c_valid = c_valid && !is_intra[xy - 1];
301    }
302
303    if (a_valid) {
304        A = s->current_picture.motion_val[dir][xy - wrap + v->blocks_off];
305        a_f = v->mv_f[dir][xy - wrap + v->blocks_off];
306        num_oppfield  += a_f;
307        num_samefield += 1 - a_f;
308        field_predA[0] = A[0];
309        field_predA[1] = A[1];
310    } else {
311        field_predA[0] = field_predA[1] = 0;
312        a_f = 0;
313    }
314    if (b_valid) {
315        B = s->current_picture.motion_val[dir][xy - wrap + off + v->blocks_off];
316        b_f = v->mv_f[dir][xy - wrap + off + v->blocks_off];
317        num_oppfield  += b_f;
318        num_samefield += 1 - b_f;
319        field_predB[0] = B[0];
320        field_predB[1] = B[1];
321    } else {
322        field_predB[0] = field_predB[1] = 0;
323        b_f = 0;
324    }
325    if (c_valid) {
326        C = s->current_picture.motion_val[dir][xy - 1 + v->blocks_off];
327        c_f = v->mv_f[dir][xy - 1 + v->blocks_off];
328        num_oppfield  += c_f;
329        num_samefield += 1 - c_f;
330        field_predC[0] = C[0];
331        field_predC[1] = C[1];
332    } else {
333        field_predC[0] = field_predC[1] = 0;
334        c_f = 0;
335    }
336
337    if (v->field_mode) {
338        if (!v->numref)
339            // REFFIELD determines if the last field or the second-last field is
340            // to be used as reference
341            opposite = 1 - v->reffield;
342        else {
343            if (num_samefield <= num_oppfield)
344                opposite = 1 - pred_flag;
345            else
346                opposite = pred_flag;
347        }
348    } else
349        opposite = 0;
350    if (opposite) {
351        v->mv_f[dir][xy + v->blocks_off] = 1;
352        v->ref_field_type[dir] = !v->cur_field_type;
353        if (a_valid && !a_f) {
354            field_predA[0] = scaleforopp(v, field_predA[0], 0, dir);
355            field_predA[1] = scaleforopp(v, field_predA[1], 1, dir);
356        }
357        if (b_valid && !b_f) {
358            field_predB[0] = scaleforopp(v, field_predB[0], 0, dir);
359            field_predB[1] = scaleforopp(v, field_predB[1], 1, dir);
360        }
361        if (c_valid && !c_f) {
362            field_predC[0] = scaleforopp(v, field_predC[0], 0, dir);
363            field_predC[1] = scaleforopp(v, field_predC[1], 1, dir);
364        }
365    } else {
366        v->mv_f[dir][xy + v->blocks_off] = 0;
367        v->ref_field_type[dir] = v->cur_field_type;
368        if (a_valid && a_f) {
369            field_predA[0] = scaleforsame(v, n, field_predA[0], 0, dir);
370            field_predA[1] = scaleforsame(v, n, field_predA[1], 1, dir);
371        }
372        if (b_valid && b_f) {
373            field_predB[0] = scaleforsame(v, n, field_predB[0], 0, dir);
374            field_predB[1] = scaleforsame(v, n, field_predB[1], 1, dir);
375        }
376        if (c_valid && c_f) {
377            field_predC[0] = scaleforsame(v, n, field_predC[0], 0, dir);
378            field_predC[1] = scaleforsame(v, n, field_predC[1], 1, dir);
379        }
380    }
381
382    if (a_valid) {
383        px = field_predA[0];
384        py = field_predA[1];
385    } else if (c_valid) {
386        px = field_predC[0];
387        py = field_predC[1];
388    } else if (b_valid) {
389        px = field_predB[0];
390        py = field_predB[1];
391    } else {
392        px = 0;
393        py = 0;
394    }
395
396    if (num_samefield + num_oppfield > 1) {
397        px = mid_pred(field_predA[0], field_predB[0], field_predC[0]);
398        py = mid_pred(field_predA[1], field_predB[1], field_predC[1]);
399    }
400
401    /* Pullback MV as specified in 8.3.5.3.4 */
402    if (!v->field_mode) {
403        int qx, qy, X, Y;
404        int MV = mv1 ? -60 : -28;
405        qx = (s->mb_x << 6) + ((n == 1 || n == 3) ? 32 : 0);
406        qy = (s->mb_y << 6) + ((n == 2 || n == 3) ? 32 : 0);
407        X  = (s->mb_width  << 6) - 4;
408        Y  = (s->mb_height << 6) - 4;
409        if (qx + px < MV) px = MV - qx;
410        if (qy + py < MV) py = MV - qy;
411        if (qx + px > X) px = X - qx;
412        if (qy + py > Y) py = Y - qy;
413    }
414
415    if (!v->field_mode || s->pict_type != AV_PICTURE_TYPE_B) {
416        /* Calculate hybrid prediction as specified in 8.3.5.3.5 (also 10.3.5.4.3.5) */
417        hybridmv_thresh = 32;
418        if (a_valid && c_valid) {
419            if (is_intra[xy - wrap])
420                sum = FFABS(px) + FFABS(py);
421            else
422                sum = FFABS(px - field_predA[0]) + FFABS(py - field_predA[1]);
423            if (sum > hybridmv_thresh) {
424                if (get_bits1(&s->gb)) {     // read HYBRIDPRED bit
425                    px = field_predA[0];
426                    py = field_predA[1];
427                } else {
428                    px = field_predC[0];
429                    py = field_predC[1];
430                }
431            } else {
432                if (is_intra[xy - 1])
433                    sum = FFABS(px) + FFABS(py);
434                else
435                    sum = FFABS(px - field_predC[0]) + FFABS(py - field_predC[1]);
436                if (sum > hybridmv_thresh) {
437                    if (get_bits1(&s->gb)) {
438                        px = field_predA[0];
439                        py = field_predA[1];
440                    } else {
441                        px = field_predC[0];
442                        py = field_predC[1];
443                    }
444                }
445            }
446        }
447    }
448
449    if (v->field_mode && v->numref)
450        r_y >>= 1;
451    if (v->field_mode && v->cur_field_type && v->ref_field_type[dir] == 0)
452        y_bias = 1;
453    /* store MV using signed modulus of MV range defined in 4.11 */
454    s->mv[dir][n][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0] = ((px + dmv_x + r_x) & ((r_x << 1) - 1)) - r_x;
455    s->mv[dir][n][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1] = ((py + dmv_y + r_y - y_bias) & ((r_y << 1) - 1)) - r_y + y_bias;
456    if (mv1) { /* duplicate motion data for 1-MV block */
457        s->current_picture.motion_val[dir][xy +    1 +     v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];
458        s->current_picture.motion_val[dir][xy +    1 +     v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];
459        s->current_picture.motion_val[dir][xy + wrap +     v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];
460        s->current_picture.motion_val[dir][xy + wrap +     v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];
461        s->current_picture.motion_val[dir][xy + wrap + 1 + v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];
462        s->current_picture.motion_val[dir][xy + wrap + 1 + v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];
463        v->mv_f[dir][xy +    1 + v->blocks_off] = v->mv_f[dir][xy +            v->blocks_off];
464        v->mv_f[dir][xy + wrap + v->blocks_off] = v->mv_f[dir][xy + wrap + 1 + v->blocks_off] = v->mv_f[dir][xy + v->blocks_off];
465    }
466}
467
468/** Predict and set motion vector for interlaced frame picture MBs
469 */
470void ff_vc1_pred_mv_intfr(VC1Context *v, int n, int dmv_x, int dmv_y,
471                          int mvn, int r_x, int r_y, int dir)
472{
473    MpegEncContext *s = &v->s;
474    int xy, wrap, off = 0;
475    int A[2], B[2], C[2];
476    int px = 0, py = 0;
477    int a_valid = 0, b_valid = 0, c_valid = 0;
478    int field_a, field_b, field_c; // 0: same, 1: opposite
479    int total_valid, num_samefield, num_oppfield;
480    int pos_c, pos_b, n_adj;
481
482    wrap = s->b8_stride;
483    xy = s->block_index[n];
484
485    if (s->mb_intra) {
486        s->mv[0][n][0] = s->current_picture.motion_val[0][xy][0] = 0;
487        s->mv[0][n][1] = s->current_picture.motion_val[0][xy][1] = 0;
488        s->current_picture.motion_val[1][xy][0] = 0;
489        s->current_picture.motion_val[1][xy][1] = 0;
490        if (mvn == 1) { /* duplicate motion data for 1-MV block */
491            s->current_picture.motion_val[0][xy + 1][0]        = 0;
492            s->current_picture.motion_val[0][xy + 1][1]        = 0;
493            s->current_picture.motion_val[0][xy + wrap][0]     = 0;
494            s->current_picture.motion_val[0][xy + wrap][1]     = 0;
495            s->current_picture.motion_val[0][xy + wrap + 1][0] = 0;
496            s->current_picture.motion_val[0][xy + wrap + 1][1] = 0;
497            v->luma_mv[s->mb_x][0] = v->luma_mv[s->mb_x][1] = 0;
498            s->current_picture.motion_val[1][xy + 1][0]        = 0;
499            s->current_picture.motion_val[1][xy + 1][1]        = 0;
500            s->current_picture.motion_val[1][xy + wrap][0]     = 0;
501            s->current_picture.motion_val[1][xy + wrap][1]     = 0;
502            s->current_picture.motion_val[1][xy + wrap + 1][0] = 0;
503            s->current_picture.motion_val[1][xy + wrap + 1][1] = 0;
504        }
505        return;
506    }
507
508    off = ((n == 0) || (n == 1)) ? 1 : -1;
509    /* predict A */
510    if (s->mb_x || (n == 1) || (n == 3)) {
511        if ((v->blk_mv_type[xy]) // current block (MB) has a field MV
512            || (!v->blk_mv_type[xy] && !v->blk_mv_type[xy - 1])) { // or both have frame MV
513            A[0] = s->current_picture.motion_val[dir][xy - 1][0];
514            A[1] = s->current_picture.motion_val[dir][xy - 1][1];
515            a_valid = 1;
516        } else { // current block has frame mv and cand. has field MV (so average)
517            A[0] = (s->current_picture.motion_val[dir][xy - 1][0]
518                    + s->current_picture.motion_val[dir][xy - 1 + off * wrap][0] + 1) >> 1;
519            A[1] = (s->current_picture.motion_val[dir][xy - 1][1]
520                    + s->current_picture.motion_val[dir][xy - 1 + off * wrap][1] + 1) >> 1;
521            a_valid = 1;
522        }
523        if (!(n & 1) && v->is_intra[s->mb_x - 1]) {
524            a_valid = 0;
525            A[0] = A[1] = 0;
526        }
527    } else
528        A[0] = A[1] = 0;
529    /* Predict B and C */
530    B[0] = B[1] = C[0] = C[1] = 0;
531    if (n == 0 || n == 1 || v->blk_mv_type[xy]) {
532        if (!s->first_slice_line) {
533            if (!v->is_intra[s->mb_x - s->mb_stride]) {
534                b_valid = 1;
535                n_adj   = n | 2;
536                pos_b   = s->block_index[n_adj] - 2 * wrap;
537                if (v->blk_mv_type[pos_b] && v->blk_mv_type[xy]) {
538                    n_adj = (n & 2) | (n & 1);
539                }
540                B[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap][0];
541                B[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap][1];
542                if (v->blk_mv_type[pos_b] && !v->blk_mv_type[xy]) {
543                    B[0] = (B[0] + s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap][0] + 1) >> 1;
544                    B[1] = (B[1] + s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap][1] + 1) >> 1;
545                }
546            }
547            if (s->mb_width > 1) {
548                if (!v->is_intra[s->mb_x - s->mb_stride + 1]) {
549                    c_valid = 1;
550                    n_adj   = 2;
551                    pos_c   = s->block_index[2] - 2 * wrap + 2;
552                    if (v->blk_mv_type[pos_c] && v->blk_mv_type[xy]) {
553                        n_adj = n & 2;
554                    }
555                    C[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap + 2][0];
556                    C[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap + 2][1];
557                    if (v->blk_mv_type[pos_c] && !v->blk_mv_type[xy]) {
558                        C[0] = (1 + C[0] + (s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap + 2][0])) >> 1;
559                        C[1] = (1 + C[1] + (s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap + 2][1])) >> 1;
560                    }
561                    if (s->mb_x == s->mb_width - 1) {
562                        if (!v->is_intra[s->mb_x - s->mb_stride - 1]) {
563                            c_valid = 1;
564                            n_adj   = 3;
565                            pos_c   = s->block_index[3] - 2 * wrap - 2;
566                            if (v->blk_mv_type[pos_c] && v->blk_mv_type[xy]) {
567                                n_adj = n | 1;
568                            }
569                            C[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap - 2][0];
570                            C[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap - 2][1];
571                            if (v->blk_mv_type[pos_c] && !v->blk_mv_type[xy]) {
572                                C[0] = (1 + C[0] + s->current_picture.motion_val[dir][s->block_index[1] - 2 * wrap - 2][0]) >> 1;
573                                C[1] = (1 + C[1] + s->current_picture.motion_val[dir][s->block_index[1] - 2 * wrap - 2][1]) >> 1;
574                            }
575                        } else
576                            c_valid = 0;
577                    }
578                }
579            }
580        }
581    } else {
582        pos_b   = s->block_index[1];
583        b_valid = 1;
584        B[0]    = s->current_picture.motion_val[dir][pos_b][0];
585        B[1]    = s->current_picture.motion_val[dir][pos_b][1];
586        pos_c   = s->block_index[0];
587        c_valid = 1;
588        C[0]    = s->current_picture.motion_val[dir][pos_c][0];
589        C[1]    = s->current_picture.motion_val[dir][pos_c][1];
590    }
591
592    total_valid = a_valid + b_valid + c_valid;
593    // check if predictor A is out of bounds
594    if (!s->mb_x && !(n == 1 || n == 3)) {
595        A[0] = A[1] = 0;
596    }
597    // check if predictor B is out of bounds
598    if ((s->first_slice_line && v->blk_mv_type[xy]) || (s->first_slice_line && !(n & 2))) {
599        B[0] = B[1] = C[0] = C[1] = 0;
600    }
601    if (!v->blk_mv_type[xy]) {
602        if (s->mb_width == 1) {
603            px = B[0];
604            py = B[1];
605        } else {
606            if (total_valid >= 2) {
607                px = mid_pred(A[0], B[0], C[0]);
608                py = mid_pred(A[1], B[1], C[1]);
609            } else if (total_valid) {
610                if      (a_valid) { px = A[0]; py = A[1]; }
611                else if (b_valid) { px = B[0]; py = B[1]; }
612                else              { px = C[0]; py = C[1]; }
613            }
614        }
615    } else {
616        if (a_valid)
617            field_a = (A[1] & 4) ? 1 : 0;
618        else
619            field_a = 0;
620        if (b_valid)
621            field_b = (B[1] & 4) ? 1 : 0;
622        else
623            field_b = 0;
624        if (c_valid)
625            field_c = (C[1] & 4) ? 1 : 0;
626        else
627            field_c = 0;
628
629        num_oppfield  = field_a + field_b + field_c;
630        num_samefield = total_valid - num_oppfield;
631        if (total_valid == 3) {
632            if ((num_samefield == 3) || (num_oppfield == 3)) {
633                px = mid_pred(A[0], B[0], C[0]);
634                py = mid_pred(A[1], B[1], C[1]);
635            } else if (num_samefield >= num_oppfield) {
636                /* take one MV from same field set depending on priority
637                the check for B may not be necessary */
638                px = !field_a ? A[0] : B[0];
639                py = !field_a ? A[1] : B[1];
640            } else {
641                px =  field_a ? A[0] : B[0];
642                py =  field_a ? A[1] : B[1];
643            }
644        } else if (total_valid == 2) {
645            if (num_samefield >= num_oppfield) {
646                if (!field_a && a_valid) {
647                    px = A[0];
648                    py = A[1];
649                } else if (!field_b && b_valid) {
650                    px = B[0];
651                    py = B[1];
652                } else /*if (c_valid)*/ {
653                    av_assert1(c_valid);
654                    px = C[0];
655                    py = C[1];
656                }
657            } else {
658                if (field_a && a_valid) {
659                    px = A[0];
660                    py = A[1];
661                } else /*if (field_b && b_valid)*/ {
662                    av_assert1(field_b && b_valid);
663                    px = B[0];
664                    py = B[1];
665                }
666            }
667        } else if (total_valid == 1) {
668            px = (a_valid) ? A[0] : ((b_valid) ? B[0] : C[0]);
669            py = (a_valid) ? A[1] : ((b_valid) ? B[1] : C[1]);
670        }
671    }
672
673    /* store MV using signed modulus of MV range defined in 4.11 */
674    s->mv[dir][n][0] = s->current_picture.motion_val[dir][xy][0] = ((px + dmv_x + r_x) & ((r_x << 1) - 1)) - r_x;
675    s->mv[dir][n][1] = s->current_picture.motion_val[dir][xy][1] = ((py + dmv_y + r_y) & ((r_y << 1) - 1)) - r_y;
676    if (mvn == 1) { /* duplicate motion data for 1-MV block */
677        s->current_picture.motion_val[dir][xy +    1    ][0] = s->current_picture.motion_val[dir][xy][0];
678        s->current_picture.motion_val[dir][xy +    1    ][1] = s->current_picture.motion_val[dir][xy][1];
679        s->current_picture.motion_val[dir][xy + wrap    ][0] = s->current_picture.motion_val[dir][xy][0];
680        s->current_picture.motion_val[dir][xy + wrap    ][1] = s->current_picture.motion_val[dir][xy][1];
681        s->current_picture.motion_val[dir][xy + wrap + 1][0] = s->current_picture.motion_val[dir][xy][0];
682        s->current_picture.motion_val[dir][xy + wrap + 1][1] = s->current_picture.motion_val[dir][xy][1];
683    } else if (mvn == 2) { /* duplicate motion data for 2-Field MV block */
684        s->current_picture.motion_val[dir][xy + 1][0] = s->current_picture.motion_val[dir][xy][0];
685        s->current_picture.motion_val[dir][xy + 1][1] = s->current_picture.motion_val[dir][xy][1];
686        s->mv[dir][n + 1][0] = s->mv[dir][n][0];
687        s->mv[dir][n + 1][1] = s->mv[dir][n][1];
688    }
689}
690
691void ff_vc1_pred_b_mv(VC1Context *v, int dmv_x[2], int dmv_y[2],
692                      int direct, int mvtype)
693{
694    MpegEncContext *s = &v->s;
695    int xy, wrap, off = 0;
696    int16_t *A, *B, *C;
697    int px, py;
698    int sum;
699    int r_x, r_y;
700    const uint8_t *is_intra = v->mb_type[0];
701
702    av_assert0(!v->field_mode);
703
704    r_x = v->range_x;
705    r_y = v->range_y;
706    /* scale MV difference to be quad-pel */
707    if (!s->quarter_sample) {
708        dmv_x[0] *= 2;
709        dmv_y[0] *= 2;
710        dmv_x[1] *= 2;
711        dmv_y[1] *= 2;
712    }
713
714    wrap = s->b8_stride;
715    xy = s->block_index[0];
716
717    if (s->mb_intra) {
718        s->current_picture.motion_val[0][xy][0] =
719        s->current_picture.motion_val[0][xy][1] =
720        s->current_picture.motion_val[1][xy][0] =
721        s->current_picture.motion_val[1][xy][1] = 0;
722        return;
723    }
724        if (direct && s->next_picture_ptr->field_picture)
725            av_log(s->avctx, AV_LOG_WARNING, "Mixed frame/field direct mode not supported\n");
726
727        s->mv[0][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 0, s->quarter_sample);
728        s->mv[0][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 0, s->quarter_sample);
729        s->mv[1][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 1, s->quarter_sample);
730        s->mv[1][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 1, s->quarter_sample);
731
732        /* Pullback predicted motion vectors as specified in 8.4.5.4 */
733        s->mv[0][0][0] = av_clip(s->mv[0][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));
734        s->mv[0][0][1] = av_clip(s->mv[0][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));
735        s->mv[1][0][0] = av_clip(s->mv[1][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));
736        s->mv[1][0][1] = av_clip(s->mv[1][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));
737    if (direct) {
738        s->current_picture.motion_val[0][xy][0] = s->mv[0][0][0];
739        s->current_picture.motion_val[0][xy][1] = s->mv[0][0][1];
740        s->current_picture.motion_val[1][xy][0] = s->mv[1][0][0];
741        s->current_picture.motion_val[1][xy][1] = s->mv[1][0][1];
742        return;
743    }
744
745    if ((mvtype == BMV_TYPE_FORWARD) || (mvtype == BMV_TYPE_INTERPOLATED)) {
746        C   = s->current_picture.motion_val[0][xy - 2];
747        A   = s->current_picture.motion_val[0][xy - wrap * 2];
748        off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;
749        B   = s->current_picture.motion_val[0][xy - wrap * 2 + off];
750
751        if (!s->mb_x) C[0] = C[1] = 0;
752        if (!s->first_slice_line) { // predictor A is not out of bounds
753            if (s->mb_width == 1) {
754                px = A[0];
755                py = A[1];
756            } else {
757                px = mid_pred(A[0], B[0], C[0]);
758                py = mid_pred(A[1], B[1], C[1]);
759            }
760        } else if (s->mb_x) { // predictor C is not out of bounds
761            px = C[0];
762            py = C[1];
763        } else {
764            px = py = 0;
765        }
766        /* Pullback MV as specified in 8.3.5.3.4 */
767        {
768            int qx, qy, X, Y;
769            int sh = v->profile < PROFILE_ADVANCED ? 5 : 6;
770            int MV = 4 - (1 << sh);
771            qx = (s->mb_x << sh);
772            qy = (s->mb_y << sh);
773            X  = (s->mb_width  << sh) - 4;
774            Y  = (s->mb_height << sh) - 4;
775            if (qx + px < MV) px = MV - qx;
776            if (qy + py < MV) py = MV - qy;
777            if (qx + px > X) px = X - qx;
778            if (qy + py > Y) py = Y - qy;
779        }
780        /* Calculate hybrid prediction as specified in 8.3.5.3.5 */
781        if (0 && !s->first_slice_line && s->mb_x) {
782            if (is_intra[xy - wrap])
783                sum = FFABS(px) + FFABS(py);
784            else
785                sum = FFABS(px - A[0]) + FFABS(py - A[1]);
786            if (sum > 32) {
787                if (get_bits1(&s->gb)) {
788                    px = A[0];
789                    py = A[1];
790                } else {
791                    px = C[0];
792                    py = C[1];
793                }
794            } else {
795                if (is_intra[xy - 2])
796                    sum = FFABS(px) + FFABS(py);
797                else
798                    sum = FFABS(px - C[0]) + FFABS(py - C[1]);
799                if (sum > 32) {
800                    if (get_bits1(&s->gb)) {
801                        px = A[0];
802                        py = A[1];
803                    } else {
804                        px = C[0];
805                        py = C[1];
806                    }
807                }
808            }
809        }
810        /* store MV using signed modulus of MV range defined in 4.11 */
811        s->mv[0][0][0] = ((px + dmv_x[0] + r_x) & ((r_x << 1) - 1)) - r_x;
812        s->mv[0][0][1] = ((py + dmv_y[0] + r_y) & ((r_y << 1) - 1)) - r_y;
813    }
814    if ((mvtype == BMV_TYPE_BACKWARD) || (mvtype == BMV_TYPE_INTERPOLATED)) {
815        C   = s->current_picture.motion_val[1][xy - 2];
816        A   = s->current_picture.motion_val[1][xy - wrap * 2];
817        off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;
818        B   = s->current_picture.motion_val[1][xy - wrap * 2 + off];
819
820        if (!s->mb_x)
821            C[0] = C[1] = 0;
822        if (!s->first_slice_line) { // predictor A is not out of bounds
823            if (s->mb_width == 1) {
824                px = A[0];
825                py = A[1];
826            } else {
827                px = mid_pred(A[0], B[0], C[0]);
828                py = mid_pred(A[1], B[1], C[1]);
829            }
830        } else if (s->mb_x) { // predictor C is not out of bounds
831            px = C[0];
832            py = C[1];
833        } else {
834            px = py = 0;
835        }
836        /* Pullback MV as specified in 8.3.5.3.4 */
837        {
838            int qx, qy, X, Y;
839            int sh = v->profile < PROFILE_ADVANCED ? 5 : 6;
840            int MV = 4 - (1 << sh);
841            qx = (s->mb_x << sh);
842            qy = (s->mb_y << sh);
843            X  = (s->mb_width  << sh) - 4;
844            Y  = (s->mb_height << sh) - 4;
845            if (qx + px < MV) px = MV - qx;
846            if (qy + py < MV) py = MV - qy;
847            if (qx + px > X) px = X - qx;
848            if (qy + py > Y) py = Y - qy;
849        }
850        /* Calculate hybrid prediction as specified in 8.3.5.3.5 */
851        if (0 && !s->first_slice_line && s->mb_x) {
852            if (is_intra[xy - wrap])
853                sum = FFABS(px) + FFABS(py);
854            else
855                sum = FFABS(px - A[0]) + FFABS(py - A[1]);
856            if (sum > 32) {
857                if (get_bits1(&s->gb)) {
858                    px = A[0];
859                    py = A[1];
860                } else {
861                    px = C[0];
862                    py = C[1];
863                }
864            } else {
865                if (is_intra[xy - 2])
866                    sum = FFABS(px) + FFABS(py);
867                else
868                    sum = FFABS(px - C[0]) + FFABS(py - C[1]);
869                if (sum > 32) {
870                    if (get_bits1(&s->gb)) {
871                        px = A[0];
872                        py = A[1];
873                    } else {
874                        px = C[0];
875                        py = C[1];
876                    }
877                }
878            }
879        }
880        /* store MV using signed modulus of MV range defined in 4.11 */
881
882        s->mv[1][0][0] = ((px + dmv_x[1] + r_x) & ((r_x << 1) - 1)) - r_x;
883        s->mv[1][0][1] = ((py + dmv_y[1] + r_y) & ((r_y << 1) - 1)) - r_y;
884    }
885    s->current_picture.motion_val[0][xy][0] = s->mv[0][0][0];
886    s->current_picture.motion_val[0][xy][1] = s->mv[0][0][1];
887    s->current_picture.motion_val[1][xy][0] = s->mv[1][0][0];
888    s->current_picture.motion_val[1][xy][1] = s->mv[1][0][1];
889}
890
891void ff_vc1_pred_b_mv_intfi(VC1Context *v, int n, int *dmv_x, int *dmv_y,
892                            int mv1, int *pred_flag)
893{
894    int dir = (v->bmvtype == BMV_TYPE_BACKWARD) ? 1 : 0;
895    MpegEncContext *s = &v->s;
896    int mb_pos = s->mb_x + s->mb_y * s->mb_stride;
897
898    if (v->bmvtype == BMV_TYPE_DIRECT) {
899        int total_opp, k, f;
900        if (s->next_picture.mb_type[mb_pos + v->mb_off] != MB_TYPE_INTRA) {
901            s->mv[0][0][0] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][0],
902                                      v->bfraction, 0, s->quarter_sample);
903            s->mv[0][0][1] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][1],
904                                      v->bfraction, 0, s->quarter_sample);
905            s->mv[1][0][0] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][0],
906                                      v->bfraction, 1, s->quarter_sample);
907            s->mv[1][0][1] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][1],
908                                      v->bfraction, 1, s->quarter_sample);
909
910            total_opp = v->mv_f_next[0][s->block_index[0] + v->blocks_off]
911                      + v->mv_f_next[0][s->block_index[1] + v->blocks_off]
912                      + v->mv_f_next[0][s->block_index[2] + v->blocks_off]
913                      + v->mv_f_next[0][s->block_index[3] + v->blocks_off];
914            f = (total_opp > 2) ? 1 : 0;
915        } else {
916            s->mv[0][0][0] = s->mv[0][0][1] = 0;
917            s->mv[1][0][0] = s->mv[1][0][1] = 0;
918            f = 0;
919        }
920        v->ref_field_type[0] = v->ref_field_type[1] = v->cur_field_type ^ f;
921        for (k = 0; k < 4; k++) {
922            s->current_picture.motion_val[0][s->block_index[k] + v->blocks_off][0] = s->mv[0][0][0];
923            s->current_picture.motion_val[0][s->block_index[k] + v->blocks_off][1] = s->mv[0][0][1];
924            s->current_picture.motion_val[1][s->block_index[k] + v->blocks_off][0] = s->mv[1][0][0];
925            s->current_picture.motion_val[1][s->block_index[k] + v->blocks_off][1] = s->mv[1][0][1];
926            v->mv_f[0][s->block_index[k] + v->blocks_off] = f;
927            v->mv_f[1][s->block_index[k] + v->blocks_off] = f;
928        }
929        return;
930    }
931    if (v->bmvtype == BMV_TYPE_INTERPOLATED) {
932        ff_vc1_pred_mv(v, 0, dmv_x[0], dmv_y[0],   1, v->range_x, v->range_y, v->mb_type[0], pred_flag[0], 0);
933        ff_vc1_pred_mv(v, 0, dmv_x[1], dmv_y[1],   1, v->range_x, v->range_y, v->mb_type[0], pred_flag[1], 1);
934        return;
935    }
936    if (dir) { // backward
937        ff_vc1_pred_mv(v, n, dmv_x[1], dmv_y[1], mv1, v->range_x, v->range_y, v->mb_type[0], pred_flag[1], 1);
938        if (n == 3 || mv1) {
939            ff_vc1_pred_mv(v, 0, dmv_x[0], dmv_y[0],   1, v->range_x, v->range_y, v->mb_type[0], 0, 0);
940        }
941    } else { // forward
942        ff_vc1_pred_mv(v, n, dmv_x[0], dmv_y[0], mv1, v->range_x, v->range_y, v->mb_type[0], pred_flag[0], 0);
943        if (n == 3 || mv1) {
944            ff_vc1_pred_mv(v, 0, dmv_x[1], dmv_y[1],   1, v->range_x, v->range_y, v->mb_type[0], 0, 1);
945        }
946    }
947}
948