FFmpeg  4.3
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=
115  s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
116  break;
117  case 3:
118  if(s->workaround_bugs){
119  s->y_dc_scale_table= ff_old_ff_y_dc_scale_table;
120  s->c_dc_scale_table= ff_wmv1_c_dc_scale_table;
121  } else{
122  s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table;
123  s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
124  }
125  break;
126  case 4:
127  case 5:
128  s->y_dc_scale_table= ff_wmv1_y_dc_scale_table;
129  s->c_dc_scale_table= ff_wmv1_c_dc_scale_table;
130  break;
131 #if CONFIG_VC1_DECODER
132  case 6:
133  s->y_dc_scale_table= ff_wmv3_dc_scale_table;
134  s->c_dc_scale_table= ff_wmv3_dc_scale_table;
135  break;
136 #endif
137 
138  }
139 
140 
141  if(s->msmpeg4_version>=4){
142  ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_wmv1_scantable[1]);
143  ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_wmv1_scantable[2]);
144  ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_wmv1_scantable[3]);
145  ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_wmv1_scantable[0]);
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 
stride
int stride
Definition: mace.c:144
ff_init_scantable
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
level
uint8_t level
Definition: svq3.c:209
ff_mpeg1_dc_scale_table
const uint8_t ff_mpeg1_dc_scale_table[128]
Definition: mpegvideodata.c:33
ff_wmv1_scantable
const uint8_t ff_wmv1_scantable[WMV1_SCANTABLE_COUNT][64]
Definition: msmpeg4data.c:1809
ff_msmpeg4_common_init
av_cold void ff_msmpeg4_common_init(MpegEncContext *s)
Definition: msmpeg4.c:109
b
#define b
Definition: input.c:41
mpegvideo.h
ff_inverse
const uint32_t ff_inverse[257]
Definition: mathtables.c:27
ff_mpeg4_DCtab_chrom
const uint8_t ff_mpeg4_DCtab_chrom[13][2]
Definition: mpeg4data.h:41
wrap
#define wrap(func)
Definition: neontest.h:65
x
FFmpeg Automated Testing Environment ************************************Introduction Using FATE from your FFmpeg source directory Submitting the results to the FFmpeg result aggregation server Uploading new samples to the fate suite FATE makefile targets and variables Makefile targets Makefile variables Examples Introduction **************FATE is an extended regression suite on the client side and a means for results aggregation and presentation on the server side The first part of this document explains how you can use FATE from your FFmpeg source directory to test your ffmpeg binary The second part describes how you can run FATE to submit the results to FFmpeg’s FATE server In any way you can have a look at the publicly viewable FATE results by visiting this as it can be seen if some test on some platform broke with their recent contribution This usually happens on the platforms the developers could not test on The second part of this document describes how you can run FATE to submit your results to FFmpeg’s FATE server If you want to submit your results be sure to check that your combination of OS and compiler is not already listed on the above mentioned website In the third part you can find a comprehensive listing of FATE makefile targets and variables Using FATE from your FFmpeg source directory **********************************************If you want to run FATE on your machine you need to have the samples in place You can get the samples via the build target fate rsync Use this command from the top level source this will cause FATE to fail NOTE To use a custom wrapper to run the pass ‘ target exec’ to ‘configure’ or set the TARGET_EXEC Make variable Submitting the results to the FFmpeg result aggregation server ****************************************************************To submit your results to the server you should run fate through the shell script ‘tests fate sh’ from the FFmpeg sources This script needs to be invoked with a configuration file as its first argument tests fate sh path to fate_config A configuration file template with comments describing the individual configuration variables can be found at ‘doc fate_config sh template’ Create a configuration that suits your based on the configuration template The ‘slot’ configuration variable can be any string that is not yet but it is suggested that you name it adhering to the following pattern ‘ARCH OS COMPILER COMPILER VERSION’ The configuration file itself will be sourced in a shell therefore all shell features may be used This enables you to setup the environment as you need it for your build For your first test runs the ‘fate_recv’ variable should be empty or commented out This will run everything as normal except that it will omit the submission of the results to the server The following files should be present in $workdir as specified in the configuration it may help to try out the ‘ssh’ command with one or more ‘ v’ options You should get detailed output concerning your SSH configuration and the authentication process The only thing left is to automate the execution of the fate sh script and the synchronisation of the samples directory Uploading new samples to the fate suite *****************************************If you need a sample uploaded send a mail to samples request This is for developers who have an account on the fate suite server If you upload new please make sure they are as small as space on each network bandwidth and so on benefit from smaller test cases Also keep in mind older checkouts use existing sample that means in practice generally do not remove or overwrite files as it likely would break older checkouts or releases Also all needed samples for a commit should be ideally before the push If you need an account for frequently uploading samples or you wish to help others by doing that send a mail to ffmpeg devel rsync vauL Duo x
Definition: fate.txt:150
ff_wmv3_dc_scale_table
const uint8_t ff_wmv3_dc_scale_table[32]
Definition: vc1data.c:648
av_cold
#define av_cold
Definition: attributes.h:90
msmpeg4data.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
ff_mpeg4_DCtab_lum
const uint8_t ff_mpeg4_DCtab_lum[13][2]
Definition: mpeg4data.h:35
ff_v2_dc_lum_table
uint32_t ff_v2_dc_lum_table[512][2]
Definition: msmpeg4data.c:34
src
#define src
Definition: vp8dsp.c:254
get_dc
static int get_dc(uint8_t *src, int stride, int scale, int block_size)
Definition: msmpeg4.c:179
ff_v2_dc_chroma_table
uint32_t ff_v2_dc_chroma_table[512][2]
Definition: msmpeg4data.c:35
abs
#define abs(x)
Definition: cuda_runtime.h:35
FASTDIV
#define FASTDIV(a, b)
Definition: mathops.h:202
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ff_mpeg4_y_dc_scale_table
const uint8_t ff_mpeg4_y_dc_scale_table[32]
Definition: mpeg4data.h:359
size
int size
Definition: twinvq_data.h:11134
asm.h
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
vc1data.h
ff_msmpeg4_pred_dc
int ff_msmpeg4_pred_dc(MpegEncContext *s, int n, int16_t **dc_val_ptr, int *dir_ptr)
Definition: msmpeg4.c:193
mpegvideodata.h
uint8_t
uint8_t
Definition: audio_convert.c:194
idctdsp.h
avcodec.h
msmpeg4.h
pred
static const float pred[4]
Definition: siprdata.h:259
ff_old_ff_y_dc_scale_table
const uint8_t ff_old_ff_y_dc_scale_table[32]
Definition: msmpeg4data.c:1804
mpeg4video.h
ff_mpeg4_c_dc_scale_table
const uint8_t ff_mpeg4_c_dc_scale_table[32]
Definition: mpeg4data.h:363
ff_wmv1_y_dc_scale_table
const uint8_t ff_wmv1_y_dc_scale_table[32]
Definition: msmpeg4data.c:1795
init_h263_dc_for_msmpeg4
static av_cold void init_h263_dc_for_msmpeg4(void)
Definition: msmpeg4.c:52
ff_wmv1_c_dc_scale_table
const uint8_t ff_wmv1_c_dc_scale_table[32]
Definition: msmpeg4data.c:1799
imgutils.h
MpegEncContext
MpegEncContext.
Definition: mpegvideo.h:81
ff_msmpeg4_coded_block_pred
int ff_msmpeg4_coded_block_pred(MpegEncContext *s, int n, uint8_t **coded_block_ptr)
Definition: msmpeg4.c:153
h263.h