1 /*
2 * MSMPEG4 backend for encoder and decoder
3 * Copyright (c) 2001 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * msmpeg4v1 & v2 stuff by 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 * MSMPEG4 backend for encoder and decoder
28 */
29
30 #include "config_components.h"
31
32 #include "libavutil/thread.h"
33
34 #include "avcodec.h"
35 #include "idctdsp.h"
36 #include "mpegvideo.h"
37 #include "msmpeg4.h"
38 #include "libavutil/x86/asm.h"
39 #include "mpeg4videodata.h"
40 #include "msmpeg4data.h"
41 #include "mpegvideodata.h"
42 #include "vc1data.h"
43 #include "libavutil/imgutils.h"
44
45 /*
46 * You can also call this codec: MPEG-4 with a twist!
47 *
48 * TODO:
49 * - (encoding) select best mv table (two choices)
50 * - (encoding) select best vlc/dc table
51 */
52
53 /* This table is practically identical to the one from H.263
54 * except that it is inverted. */
init_h263_dc_for_msmpeg4(void)55 static av_cold void init_h263_dc_for_msmpeg4(void)
56 {
57 for (int level = -256; level < 256; level++) {
58 int uni_code, uni_len;
59 int size, v, l;
60 /* find number of bits */
61 size = 0;
62 v = abs(level);
63 while (v) {
64 v >>= 1;
65 size++;
66 }
67
68 if (level < 0)
69 l = (-level) ^ ((1 << size) - 1);
70 else
71 l = level;
72
73 /* luminance H.263 */
74 uni_code = ff_mpeg4_DCtab_lum[size][0];
75 uni_len = ff_mpeg4_DCtab_lum[size][1];
76 uni_code ^= (1 << uni_len) - 1; //M$ does not like compatibility
77
78 if (size > 0) {
79 uni_code <<= size; uni_code |= l;
80 uni_len += size;
81 if (size > 8) {
82 uni_code <<= 1; uni_code |= 1;
83 uni_len++;
84 }
85 }
86 ff_v2_dc_lum_table[level + 256][0] = uni_code;
87 ff_v2_dc_lum_table[level + 256][1] = uni_len;
88
89 /* chrominance H.263 */
90 uni_code = ff_mpeg4_DCtab_chrom[size][0];
91 uni_len = ff_mpeg4_DCtab_chrom[size][1];
92 uni_code ^= (1 << uni_len) - 1; //M$ does not like compatibility
93
94 if (size > 0) {
95 uni_code <<= size; uni_code |= l;
96 uni_len +=size;
97 if (size > 8) {
98 uni_code <<= 1; uni_code |= 1;
99 uni_len++;
100 }
101 }
102 ff_v2_dc_chroma_table[level + 256][0] = uni_code;
103 ff_v2_dc_chroma_table[level + 256][1] = uni_len;
104 }
105 }
106
msmpeg4_common_init_static(void)107 static av_cold void msmpeg4_common_init_static(void)
108 {
109 static uint8_t rl_table_store[NB_RL_TABLES][2][2 * MAX_RUN + MAX_LEVEL + 3];
110
111 for (int i = 0; i < NB_RL_TABLES; i++)
112 ff_rl_init(&ff_rl_table[i], rl_table_store[i]);
113
114 init_h263_dc_for_msmpeg4();
115 }
116
ff_msmpeg4_common_init(MpegEncContext * s)117 av_cold void ff_msmpeg4_common_init(MpegEncContext *s)
118 {
119 static AVOnce init_static_once = AV_ONCE_INIT;
120
121 switch(s->msmpeg4_version){
122 case 1:
123 case 2:
124 s->y_dc_scale_table=
125 s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
126 break;
127 case 3:
128 if(s->workaround_bugs){
129 s->y_dc_scale_table= ff_old_ff_y_dc_scale_table;
130 s->c_dc_scale_table= ff_wmv1_c_dc_scale_table;
131 } else{
132 s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table;
133 s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
134 }
135 break;
136 case 4:
137 case 5:
138 s->y_dc_scale_table= ff_wmv1_y_dc_scale_table;
139 s->c_dc_scale_table= ff_wmv1_c_dc_scale_table;
140 break;
141 #if CONFIG_VC1_DECODER
142 case 6:
143 s->y_dc_scale_table= ff_wmv3_dc_scale_table;
144 s->c_dc_scale_table= ff_wmv3_dc_scale_table;
145 break;
146 #endif
147
148 }
149
150
151 if(s->msmpeg4_version>=4){
152 ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_wmv1_scantable[1]);
153 ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_wmv1_scantable[2]);
154 ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_wmv1_scantable[3]);
155 ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_wmv1_scantable[0]);
156 }
157 //Note the default tables are set in common_init in mpegvideo.c
158
159 ff_thread_once(&init_static_once, msmpeg4_common_init_static);
160 }
161
162 /* predict coded block */
ff_msmpeg4_coded_block_pred(MpegEncContext * s,int n,uint8_t ** coded_block_ptr)163 int ff_msmpeg4_coded_block_pred(MpegEncContext * s, int n, uint8_t **coded_block_ptr)
164 {
165 int xy, wrap, pred, a, b, c;
166
167 xy = s->block_index[n];
168 wrap = s->b8_stride;
169
170 /* B C
171 * A X
172 */
173 a = s->coded_block[xy - 1 ];
174 b = s->coded_block[xy - 1 - wrap];
175 c = s->coded_block[xy - wrap];
176
177 if (b == c) {
178 pred = a;
179 } else {
180 pred = c;
181 }
182
183 /* store value */
184 *coded_block_ptr = &s->coded_block[xy];
185
186 return pred;
187 }
188
get_dc(uint8_t * src,int stride,int scale,int block_size)189 static int get_dc(uint8_t *src, int stride, int scale, int block_size)
190 {
191 int y;
192 int sum=0;
193 for(y=0; y<block_size; y++){
194 int x;
195 for(x=0; x<block_size; x++){
196 sum+=src[x + y*stride];
197 }
198 }
199 return FASTDIV((sum + (scale>>1)), scale);
200 }
201
202 /* dir = 0: left, dir = 1: top prediction */
ff_msmpeg4_pred_dc(MpegEncContext * s,int n,int16_t ** dc_val_ptr,int * dir_ptr)203 int ff_msmpeg4_pred_dc(MpegEncContext *s, int n,
204 int16_t **dc_val_ptr, int *dir_ptr)
205 {
206 int a, b, c, wrap, pred, scale;
207 int16_t *dc_val;
208
209 /* find prediction */
210 if (n < 4) {
211 scale = s->y_dc_scale;
212 } else {
213 scale = s->c_dc_scale;
214 }
215
216 wrap = s->block_wrap[n];
217 dc_val= s->dc_val[0] + s->block_index[n];
218
219 /* B C
220 * A X
221 */
222 a = dc_val[ - 1];
223 b = dc_val[ - 1 - wrap];
224 c = dc_val[ - wrap];
225
226 if(s->first_slice_line && (n&2)==0 && s->msmpeg4_version<4){
227 b=c=1024;
228 }
229
230 /* XXX: the following solution consumes divisions, but it does not
231 necessitate to modify mpegvideo.c. The problem comes from the
232 fact they decided to store the quantized DC (which would lead
233 to problems if Q could vary !) */
234 #if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE
235 __asm__ volatile(
236 "movl %3, %%eax \n\t"
237 "shrl $1, %%eax \n\t"
238 "addl %%eax, %2 \n\t"
239 "addl %%eax, %1 \n\t"
240 "addl %0, %%eax \n\t"
241 "imull %4 \n\t"
242 "movl %%edx, %0 \n\t"
243 "movl %1, %%eax \n\t"
244 "imull %4 \n\t"
245 "movl %%edx, %1 \n\t"
246 "movl %2, %%eax \n\t"
247 "imull %4 \n\t"
248 "movl %%edx, %2 \n\t"
249 : "+b" (a), "+c" (b), "+D" (c)
250 : "g" (scale), "S" (ff_inverse[scale])
251 : "%eax", "%edx"
252 );
253 #else
254 /* Divisions are costly everywhere; optimize the most common case. */
255 if (scale == 8) {
256 a = (a + (8 >> 1)) / 8;
257 b = (b + (8 >> 1)) / 8;
258 c = (c + (8 >> 1)) / 8;
259 } else {
260 a = FASTDIV((a + (scale >> 1)), scale);
261 b = FASTDIV((b + (scale >> 1)), scale);
262 c = FASTDIV((c + (scale >> 1)), scale);
263 }
264 #endif
265 /* XXX: WARNING: they did not choose the same test as MPEG-4. This
266 is very important ! */
267 if(s->msmpeg4_version>3){
268 if(s->inter_intra_pred){
269 uint8_t *dest;
270 int wrap;
271
272 if(n==1){
273 pred=a;
274 *dir_ptr = 0;
275 }else if(n==2){
276 pred=c;
277 *dir_ptr = 1;
278 }else if(n==3){
279 if (abs(a - b) < abs(b - c)) {
280 pred = c;
281 *dir_ptr = 1;
282 } else {
283 pred = a;
284 *dir_ptr = 0;
285 }
286 }else{
287 int bs = 8 >> s->avctx->lowres;
288 if(n<4){
289 wrap= s->linesize;
290 dest= s->current_picture.f->data[0] + (((n >> 1) + 2*s->mb_y) * bs* wrap ) + ((n & 1) + 2*s->mb_x) * bs;
291 }else{
292 wrap= s->uvlinesize;
293 dest= s->current_picture.f->data[n - 3] + (s->mb_y * bs * wrap) + s->mb_x * bs;
294 }
295 if(s->mb_x==0) a= (1024 + (scale>>1))/scale;
296 else a= get_dc(dest-bs, wrap, scale*8>>(2*s->avctx->lowres), bs);
297 if(s->mb_y==0) c= (1024 + (scale>>1))/scale;
298 else c= get_dc(dest-bs*wrap, wrap, scale*8>>(2*s->avctx->lowres), bs);
299
300 if (s->h263_aic_dir==0) {
301 pred= a;
302 *dir_ptr = 0;
303 }else if (s->h263_aic_dir==1) {
304 if(n==0){
305 pred= c;
306 *dir_ptr = 1;
307 }else{
308 pred= a;
309 *dir_ptr = 0;
310 }
311 }else if (s->h263_aic_dir==2) {
312 if(n==0){
313 pred= a;
314 *dir_ptr = 0;
315 }else{
316 pred= c;
317 *dir_ptr = 1;
318 }
319 } else {
320 pred= c;
321 *dir_ptr = 1;
322 }
323 }
324 }else{
325 if (abs(a - b) < abs(b - c)) {
326 pred = c;
327 *dir_ptr = 1;
328 } else {
329 pred = a;
330 *dir_ptr = 0;
331 }
332 }
333 }else{
334 if (abs(a - b) <= abs(b - c)) {
335 pred = c;
336 *dir_ptr = 1;
337 } else {
338 pred = a;
339 *dir_ptr = 0;
340 }
341 }
342
343 /* update predictor */
344 *dc_val_ptr = &dc_val[0];
345 return pred;
346 }
347
348