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msmpeg4.c
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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 "avcodec.h"
31 #include "idctdsp.h"
32 #include "mpegvideo.h"
33 #include "msmpeg4.h"
34 #include "libavutil/x86/asm.h"
35 #include "h263.h"
36 #include "mpeg4video.h"
37 #include "msmpeg4data.h"
38 #include "mpegvideodata.h"
39 #include "vc1data.h"
40 #include "libavutil/imgutils.h"
41 
42 /*
43  * You can also call this codec: MPEG-4 with a twist!
44  *
45  * TODO:
46  * - (encoding) select best mv table (two choices)
47  * - (encoding) select best vlc/dc table
48  */
49 
50 /* This table is practically identical to the one from H.263
51  * except that it is inverted. */
53 {
54  int level, uni_code, uni_len;
55 
56  if(ff_v2_dc_chroma_table[255 + 256][1])
57  return;
58 
59  for(level=-256; level<256; level++){
60  int size, v, l;
61  /* find number of bits */
62  size = 0;
63  v = abs(level);
64  while (v) {
65  v >>= 1;
66  size++;
67  }
68 
69  if (level < 0)
70  l= (-level) ^ ((1 << size) - 1);
71  else
72  l= level;
73 
74  /* luminance H.263 */
75  uni_code= ff_mpeg4_DCtab_lum[size][0];
76  uni_len = ff_mpeg4_DCtab_lum[size][1];
77  uni_code ^= (1<<uni_len)-1; //M$ does not like compatibility
78 
79  if (size > 0) {
80  uni_code<<=size; uni_code|=l;
81  uni_len+=size;
82  if (size > 8){
83  uni_code<<=1; uni_code|=1;
84  uni_len++;
85  }
86  }
87  ff_v2_dc_lum_table[level + 256][0] = uni_code;
88  ff_v2_dc_lum_table[level + 256][1] = uni_len;
89 
90  /* chrominance H.263 */
91  uni_code= ff_mpeg4_DCtab_chrom[size][0];
92  uni_len = ff_mpeg4_DCtab_chrom[size][1];
93  uni_code ^= (1<<uni_len)-1; //M$ does not like compatibility
94 
95  if (size > 0) {
96  uni_code<<=size; uni_code|=l;
97  uni_len+=size;
98  if (size > 8){
99  uni_code<<=1; uni_code|=1;
100  uni_len++;
101  }
102  }
103  ff_v2_dc_chroma_table[level + 256][0] = uni_code;
104  ff_v2_dc_chroma_table[level + 256][1] = uni_len;
105 
106  }
107 }
108 
110 {
111  switch(s->msmpeg4_version){
112  case 1:
113  case 2:
114  s->y_dc_scale_table=
116  break;
117  case 3:
118  if(s->workaround_bugs){
121  } else{
124  }
125  break;
126  case 4:
127  case 5:
130  break;
131 #if CONFIG_VC1_DECODER
132  case 6:
135  break;
136 #endif
137 
138  }
139 
140 
141  if(s->msmpeg4_version>=4){
146  }
147  //Note the default tables are set in common_init in mpegvideo.c
148 
150 }
151 
152 /* predict coded block */
153 int ff_msmpeg4_coded_block_pred(MpegEncContext * s, int n, uint8_t **coded_block_ptr)
154 {
155  int xy, wrap, pred, a, b, c;
156 
157  xy = s->block_index[n];
158  wrap = s->b8_stride;
159 
160  /* B C
161  * A X
162  */
163  a = s->coded_block[xy - 1 ];
164  b = s->coded_block[xy - 1 - wrap];
165  c = s->coded_block[xy - wrap];
166 
167  if (b == c) {
168  pred = a;
169  } else {
170  pred = c;
171  }
172 
173  /* store value */
174  *coded_block_ptr = &s->coded_block[xy];
175 
176  return pred;
177 }
178 
179 static int get_dc(uint8_t *src, int stride, int scale, int block_size)
180 {
181  int y;
182  int sum=0;
183  for(y=0; y<block_size; y++){
184  int x;
185  for(x=0; x<block_size; x++){
186  sum+=src[x + y*stride];
187  }
188  }
189  return FASTDIV((sum + (scale>>1)), scale);
190 }
191 
192 /* dir = 0: left, dir = 1: top prediction */
194  int16_t **dc_val_ptr, int *dir_ptr)
195 {
196  int a, b, c, wrap, pred, scale;
197  int16_t *dc_val;
198 
199  /* find prediction */
200  if (n < 4) {
201  scale = s->y_dc_scale;
202  } else {
203  scale = s->c_dc_scale;
204  }
205 
206  wrap = s->block_wrap[n];
207  dc_val= s->dc_val[0] + s->block_index[n];
208 
209  /* B C
210  * A X
211  */
212  a = dc_val[ - 1];
213  b = dc_val[ - 1 - wrap];
214  c = dc_val[ - wrap];
215 
216  if(s->first_slice_line && (n&2)==0 && s->msmpeg4_version<4){
217  b=c=1024;
218  }
219 
220  /* XXX: the following solution consumes divisions, but it does not
221  necessitate to modify mpegvideo.c. The problem comes from the
222  fact they decided to store the quantized DC (which would lead
223  to problems if Q could vary !) */
224 #if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE
225  __asm__ volatile(
226  "movl %3, %%eax \n\t"
227  "shrl $1, %%eax \n\t"
228  "addl %%eax, %2 \n\t"
229  "addl %%eax, %1 \n\t"
230  "addl %0, %%eax \n\t"
231  "imull %4 \n\t"
232  "movl %%edx, %0 \n\t"
233  "movl %1, %%eax \n\t"
234  "imull %4 \n\t"
235  "movl %%edx, %1 \n\t"
236  "movl %2, %%eax \n\t"
237  "imull %4 \n\t"
238  "movl %%edx, %2 \n\t"
239  : "+b" (a), "+c" (b), "+D" (c)
240  : "g" (scale), "S" (ff_inverse[scale])
241  : "%eax", "%edx"
242  );
243 #else
244  /* Divisions are costly everywhere; optimize the most common case. */
245  if (scale == 8) {
246  a = (a + (8 >> 1)) / 8;
247  b = (b + (8 >> 1)) / 8;
248  c = (c + (8 >> 1)) / 8;
249  } else {
250  a = FASTDIV((a + (scale >> 1)), scale);
251  b = FASTDIV((b + (scale >> 1)), scale);
252  c = FASTDIV((c + (scale >> 1)), scale);
253  }
254 #endif
255  /* XXX: WARNING: they did not choose the same test as MPEG-4. This
256  is very important ! */
257  if(s->msmpeg4_version>3){
258  if(s->inter_intra_pred){
259  uint8_t *dest;
260  int wrap;
261 
262  if(n==1){
263  pred=a;
264  *dir_ptr = 0;
265  }else if(n==2){
266  pred=c;
267  *dir_ptr = 1;
268  }else if(n==3){
269  if (abs(a - b) < abs(b - c)) {
270  pred = c;
271  *dir_ptr = 1;
272  } else {
273  pred = a;
274  *dir_ptr = 0;
275  }
276  }else{
277  int bs = 8 >> s->avctx->lowres;
278  if(n<4){
279  wrap= s->linesize;
280  dest= s->current_picture.f->data[0] + (((n >> 1) + 2*s->mb_y) * bs* wrap ) + ((n & 1) + 2*s->mb_x) * bs;
281  }else{
282  wrap= s->uvlinesize;
283  dest= s->current_picture.f->data[n - 3] + (s->mb_y * bs * wrap) + s->mb_x * bs;
284  }
285  if(s->mb_x==0) a= (1024 + (scale>>1))/scale;
286  else a= get_dc(dest-bs, wrap, scale*8>>(2*s->avctx->lowres), bs);
287  if(s->mb_y==0) c= (1024 + (scale>>1))/scale;
288  else c= get_dc(dest-bs*wrap, wrap, scale*8>>(2*s->avctx->lowres), bs);
289 
290  if (s->h263_aic_dir==0) {
291  pred= a;
292  *dir_ptr = 0;
293  }else if (s->h263_aic_dir==1) {
294  if(n==0){
295  pred= c;
296  *dir_ptr = 1;
297  }else{
298  pred= a;
299  *dir_ptr = 0;
300  }
301  }else if (s->h263_aic_dir==2) {
302  if(n==0){
303  pred= a;
304  *dir_ptr = 0;
305  }else{
306  pred= c;
307  *dir_ptr = 1;
308  }
309  } else {
310  pred= c;
311  *dir_ptr = 1;
312  }
313  }
314  }else{
315  if (abs(a - b) < abs(b - c)) {
316  pred = c;
317  *dir_ptr = 1;
318  } else {
319  pred = a;
320  *dir_ptr = 0;
321  }
322  }
323  }else{
324  if (abs(a - b) <= abs(b - c)) {
325  pred = c;
326  *dir_ptr = 1;
327  } else {
328  pred = a;
329  *dir_ptr = 0;
330  }
331  }
332 
333  /* update predictor */
334  *dc_val_ptr = &dc_val[0];
335  return pred;
336 }
337 
int inter_intra_pred
Definition: mpegvideo.h:441
IDCTDSPContext idsp
Definition: mpegvideo.h:227
const char * s
Definition: avisynth_c.h:631
ScanTable intra_v_scantable
Definition: mpegvideo.h:90
const uint8_t ff_mpeg4_c_dc_scale_table[32]
Definition: mpeg4data.h:363
const uint8_t * y_dc_scale_table
qscale -> y_dc_scale table
Definition: mpegvideo.h:185
uint32_t ff_v2_dc_lum_table[512][2]
Definition: msmpeg4data.c:34
misc image utilities
uint32_t ff_v2_dc_chroma_table[512][2]
Definition: msmpeg4data.c:35
int msmpeg4_version
0=not msmpeg4, 1=mp41, 2=mp42, 3=mp43/divx3 4=wmv1/7 5=wmv2/8
Definition: mpegvideo.h:435
const char * b
Definition: vf_curves.c:113
mpegvideo header.
av_cold void ff_msmpeg4_common_init(MpegEncContext *s)
Definition: msmpeg4.c:109
int block_wrap[6]
Definition: mpegvideo.h:294
VC-1 tables.
const uint8_t ff_mpeg1_dc_scale_table[128]
Definition: mpegvideodata.c:34
const uint32_t ff_inverse[257]
Definition: mathtables.c:27
uint8_t
#define av_cold
Definition: attributes.h:82
const uint8_t ff_wmv3_dc_scale_table[32]
Definition: vc1data.c:648
Picture current_picture
copy of the current picture structure.
Definition: mpegvideo.h:177
const uint8_t ff_mpeg4_DCtab_chrom[13][2]
Definition: mpeg4data.h:41
MSMPEG4 data tables.
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:3067
ptrdiff_t size
Definition: opengl_enc.c:101
const uint8_t ff_wmv1_c_dc_scale_table[32]
Definition: msmpeg4data.c:1799
int16_t * dc_val[3]
used for MPEG-4 DC prediction, all 3 arrays must be continuous
Definition: mpegvideo.h:184
#define wrap(func)
Definition: neontest.h:65
const uint8_t ff_mpeg4_DCtab_lum[13][2]
Definition: mpeg4data.h:35
const uint8_t ff_wmv1_scantable[WMV1_SCANTABLE_COUNT][64]
Definition: msmpeg4data.c:1809
int ff_msmpeg4_pred_dc(MpegEncContext *s, int n, int16_t **dc_val_ptr, int *dir_ptr)
Definition: msmpeg4.c:193
const uint8_t ff_mpeg4_y_dc_scale_table[32]
Definition: mpeg4data.h:359
int n
Definition: avisynth_c.h:547
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:94
#define src
Definition: vp9dsp.c:530
int block_index[6]
index to current MB in block based arrays with edges
Definition: mpegvideo.h:293
static const float pred[4]
Definition: siprdata.h:259
int first_slice_line
used in MPEG-4 too to handle resync markers
Definition: mpegvideo.h:433
Libavcodec external API header.
ptrdiff_t linesize
line size, in bytes, may be different from width
Definition: mpegvideo.h:131
static int get_dc(uint8_t *src, int stride, int scale, int block_size)
Definition: msmpeg4.c:179
#define FASTDIV(a, b)
Definition: mathops.h:211
ScanTable intra_scantable
Definition: mpegvideo.h:88
uint8_t * coded_block
used for coded block pattern prediction (msmpeg4v3, wmv1)
Definition: mpegvideo.h:189
ScanTable intra_h_scantable
Definition: mpegvideo.h:89
struct AVFrame * f
Definition: mpegpicture.h:46
ptrdiff_t uvlinesize
line size, for chroma in bytes, may be different from width
Definition: mpegvideo.h:132
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
const uint8_t * c_dc_scale_table
qscale -> c_dc_scale table
Definition: mpegvideo.h:186
uint8_t level
Definition: svq3.c:207
int b8_stride
2*mb_width+1 used for some 8x8 block arrays to allow simple addressing
Definition: mpegvideo.h:128
MpegEncContext.
Definition: mpegvideo.h:78
struct AVCodecContext * avctx
Definition: mpegvideo.h:95
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
static double c[64]
const uint8_t ff_wmv1_y_dc_scale_table[32]
Definition: msmpeg4data.c:1795
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
const uint8_t ff_old_ff_y_dc_scale_table[32]
Definition: msmpeg4data.c:1804
int workaround_bugs
workaround bugs in encoders which cannot be detected automatically
Definition: mpegvideo.h:116
ScanTable inter_scantable
if inter == intra then intra should be used to reduce the cache usage
Definition: mpegvideo.h:87
int ff_msmpeg4_coded_block_pred(MpegEncContext *s, int n, uint8_t **coded_block_ptr)
Definition: msmpeg4.c:153
#define stride
int h263_aic_dir
AIC direction: 0 = left, 1 = top.
Definition: mpegvideo.h:376
static av_cold void init_h263_dc_for_msmpeg4(void)
Definition: msmpeg4.c:52