imgconvert.c
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1 /*
2  * Misc image conversion routines
3  * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 /* TODO:
28  * - write 'ffimg' program to test all the image related stuff
29  * - move all api to slice based system
30  * - integrate deinterlacing, postprocessing and scaling in the conversion process
31  */
32 
33 #include "avcodec.h"
34 #include "dsputil.h"
35 #include "internal.h"
36 #include "libavutil/colorspace.h"
37 #include "libavutil/common.h"
38 #include "libavutil/pixdesc.h"
39 #include "libavutil/imgutils.h"
40 
41 #if HAVE_MMX_EXTERNAL
42 #include "x86/dsputil_mmx.h"
43 #endif
44 
45 #if HAVE_MMX_EXTERNAL
46 #define deinterlace_line_inplace ff_deinterlace_line_inplace_mmx
47 #define deinterlace_line ff_deinterlace_line_mmx
48 #else
49 #define deinterlace_line_inplace deinterlace_line_inplace_c
50 #define deinterlace_line deinterlace_line_c
51 #endif
52 
53 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift)
54 {
55  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
56  *h_shift = desc->log2_chroma_w;
57  *v_shift = desc->log2_chroma_h;
58 }
59 
60 static int is_gray(const AVPixFmtDescriptor *desc)
61 {
62  return desc->nb_components - (desc->flags & PIX_FMT_ALPHA) == 1;
63 }
64 
66  enum AVPixelFormat src_pix_fmt,
67  int has_alpha)
68 {
69  const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
70  const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
71  int loss, i, nb_components = FFMIN(src_desc->nb_components,
72  dst_desc->nb_components);
73 
74  /* compute loss */
75  loss = 0;
76 
77  if (dst_pix_fmt == src_pix_fmt)
78  return 0;
79 
80  for (i = 0; i < nb_components; i++)
81  if (src_desc->comp[i].depth_minus1 > dst_desc->comp[i].depth_minus1)
82  loss |= FF_LOSS_DEPTH;
83 
84  if (dst_desc->log2_chroma_w > src_desc->log2_chroma_w ||
85  dst_desc->log2_chroma_h > src_desc->log2_chroma_h)
86  loss |= FF_LOSS_RESOLUTION;
87 
88  if ((src_desc->flags & PIX_FMT_RGB) != (dst_desc->flags & PIX_FMT_RGB))
89  loss |= FF_LOSS_COLORSPACE;
90 
91  if (has_alpha && !(dst_desc->flags & PIX_FMT_ALPHA) &&
92  (dst_desc->flags & PIX_FMT_ALPHA))
93  loss |= FF_LOSS_ALPHA;
94 
95  if (dst_pix_fmt == AV_PIX_FMT_PAL8 && !is_gray(src_desc))
96  return loss | FF_LOSS_COLORQUANT;
97 
98  if (src_desc->nb_components > dst_desc->nb_components)
99  if (is_gray(dst_desc))
100  loss |= FF_LOSS_CHROMA;
101 
102  return loss;
103 }
104 
106  enum AVPixelFormat src_pix_fmt,
107  int has_alpha,
108  int loss_mask)
109 {
110  int dist, i, loss, min_dist;
111  enum AVPixelFormat dst_pix_fmt;
112 
113  /* find exact color match with smallest size */
114  dst_pix_fmt = AV_PIX_FMT_NONE;
115  min_dist = 0x7fffffff;
116  i = 0;
117  while (pix_fmt_list[i] != AV_PIX_FMT_NONE) {
118  enum AVPixelFormat pix_fmt = pix_fmt_list[i];
119 
120  if (i > AV_PIX_FMT_NB) {
121  av_log(NULL, AV_LOG_ERROR, "Pixel format list longer than expected, "
122  "it is either not properly terminated or contains duplicates\n");
123  return AV_PIX_FMT_NONE;
124  }
125 
126  loss = avcodec_get_pix_fmt_loss(pix_fmt, src_pix_fmt, has_alpha) & loss_mask;
127  if (loss == 0) {
129  if (dist < min_dist) {
130  min_dist = dist;
131  dst_pix_fmt = pix_fmt;
132  }
133  }
134  i++;
135  }
136  return dst_pix_fmt;
137 }
138 
139 #if FF_API_FIND_BEST_PIX_FMT
140 enum AVPixelFormat avcodec_find_best_pix_fmt(int64_t pix_fmt_mask, enum AVPixelFormat src_pix_fmt,
141  int has_alpha, int *loss_ptr)
142 {
143  enum AVPixelFormat list[64];
144  int i, j = 0;
145 
146  // test only the first 64 pixel formats to avoid undefined behaviour
147  for (i = 0; i < 64; i++) {
148  if (pix_fmt_mask & (1ULL << i))
149  list[j++] = i;
150  }
151  list[j] = AV_PIX_FMT_NONE;
152 
153  return avcodec_find_best_pix_fmt2(list, src_pix_fmt, has_alpha, loss_ptr);
154 }
155 #endif /* FF_API_FIND_BEST_PIX_FMT */
156 
158  enum AVPixelFormat src_pix_fmt,
159  int has_alpha, int *loss_ptr)
160 {
161  enum AVPixelFormat dst_pix_fmt;
162  int loss_mask, i;
163  static const int loss_mask_order[] = {
164  ~0, /* no loss first */
165  ~FF_LOSS_ALPHA,
169  ~FF_LOSS_DEPTH,
170  0,
171  };
172 
173  /* try with successive loss */
174  i = 0;
175  for(;;) {
176  loss_mask = loss_mask_order[i++];
177  dst_pix_fmt = avcodec_find_best_pix_fmt1(pix_fmt_list, src_pix_fmt,
178  has_alpha, loss_mask);
179  if (dst_pix_fmt >= 0)
180  goto found;
181  if (loss_mask == 0)
182  break;
183  }
184  return AV_PIX_FMT_NONE;
185  found:
186  if (loss_ptr)
187  *loss_ptr = avcodec_get_pix_fmt_loss(dst_pix_fmt, src_pix_fmt, has_alpha);
188  return dst_pix_fmt;
189 }
190 
191 /* 2x2 -> 1x1 */
192 void ff_shrink22(uint8_t *dst, int dst_wrap,
193  const uint8_t *src, int src_wrap,
194  int width, int height)
195 {
196  int w;
197  const uint8_t *s1, *s2;
198  uint8_t *d;
199 
200  for(;height > 0; height--) {
201  s1 = src;
202  s2 = s1 + src_wrap;
203  d = dst;
204  for(w = width;w >= 4; w-=4) {
205  d[0] = (s1[0] + s1[1] + s2[0] + s2[1] + 2) >> 2;
206  d[1] = (s1[2] + s1[3] + s2[2] + s2[3] + 2) >> 2;
207  d[2] = (s1[4] + s1[5] + s2[4] + s2[5] + 2) >> 2;
208  d[3] = (s1[6] + s1[7] + s2[6] + s2[7] + 2) >> 2;
209  s1 += 8;
210  s2 += 8;
211  d += 4;
212  }
213  for(;w > 0; w--) {
214  d[0] = (s1[0] + s1[1] + s2[0] + s2[1] + 2) >> 2;
215  s1 += 2;
216  s2 += 2;
217  d++;
218  }
219  src += 2 * src_wrap;
220  dst += dst_wrap;
221  }
222 }
223 
224 /* 4x4 -> 1x1 */
225 void ff_shrink44(uint8_t *dst, int dst_wrap,
226  const uint8_t *src, int src_wrap,
227  int width, int height)
228 {
229  int w;
230  const uint8_t *s1, *s2, *s3, *s4;
231  uint8_t *d;
232 
233  for(;height > 0; height--) {
234  s1 = src;
235  s2 = s1 + src_wrap;
236  s3 = s2 + src_wrap;
237  s4 = s3 + src_wrap;
238  d = dst;
239  for(w = width;w > 0; w--) {
240  d[0] = (s1[0] + s1[1] + s1[2] + s1[3] +
241  s2[0] + s2[1] + s2[2] + s2[3] +
242  s3[0] + s3[1] + s3[2] + s3[3] +
243  s4[0] + s4[1] + s4[2] + s4[3] + 8) >> 4;
244  s1 += 4;
245  s2 += 4;
246  s3 += 4;
247  s4 += 4;
248  d++;
249  }
250  src += 4 * src_wrap;
251  dst += dst_wrap;
252  }
253 }
254 
255 /* 8x8 -> 1x1 */
256 void ff_shrink88(uint8_t *dst, int dst_wrap,
257  const uint8_t *src, int src_wrap,
258  int width, int height)
259 {
260  int w, i;
261 
262  for(;height > 0; height--) {
263  for(w = width;w > 0; w--) {
264  int tmp=0;
265  for(i=0; i<8; i++){
266  tmp += src[0] + src[1] + src[2] + src[3] + src[4] + src[5] + src[6] + src[7];
267  src += src_wrap;
268  }
269  *(dst++) = (tmp + 32)>>6;
270  src += 8 - 8*src_wrap;
271  }
272  src += 8*src_wrap - 8*width;
273  dst += dst_wrap - width;
274  }
275 }
276 
277 /* return true if yuv planar */
278 static inline int is_yuv_planar(const AVPixFmtDescriptor *desc)
279 {
280  return (!(desc->flags & PIX_FMT_RGB) &&
281  (desc->flags & PIX_FMT_PLANAR));
282 }
283 
284 int av_picture_crop(AVPicture *dst, const AVPicture *src,
285  enum AVPixelFormat pix_fmt, int top_band, int left_band)
286 {
287  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
288  int y_shift;
289  int x_shift;
290 
291  if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB || !is_yuv_planar(desc))
292  return -1;
293 
294  y_shift = desc->log2_chroma_h;
295  x_shift = desc->log2_chroma_w;
296 
297  dst->data[0] = src->data[0] + (top_band * src->linesize[0]) + left_band;
298  dst->data[1] = src->data[1] + ((top_band >> y_shift) * src->linesize[1]) + (left_band >> x_shift);
299  dst->data[2] = src->data[2] + ((top_band >> y_shift) * src->linesize[2]) + (left_band >> x_shift);
300 
301  dst->linesize[0] = src->linesize[0];
302  dst->linesize[1] = src->linesize[1];
303  dst->linesize[2] = src->linesize[2];
304  return 0;
305 }
306 
307 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width,
308  enum AVPixelFormat pix_fmt, int padtop, int padbottom, int padleft, int padright,
309  int *color)
310 {
311  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
312  uint8_t *optr;
313  int y_shift;
314  int x_shift;
315  int yheight;
316  int i, y;
317 
318  if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB ||
319  !is_yuv_planar(desc)) return -1;
320 
321  for (i = 0; i < 3; i++) {
322  x_shift = i ? desc->log2_chroma_w : 0;
323  y_shift = i ? desc->log2_chroma_h : 0;
324 
325  if (padtop || padleft) {
326  memset(dst->data[i], color[i],
327  dst->linesize[i] * (padtop >> y_shift) + (padleft >> x_shift));
328  }
329 
330  if (padleft || padright) {
331  optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
332  (dst->linesize[i] - (padright >> x_shift));
333  yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
334  for (y = 0; y < yheight; y++) {
335  memset(optr, color[i], (padleft + padright) >> x_shift);
336  optr += dst->linesize[i];
337  }
338  }
339 
340  if (src) { /* first line */
341  uint8_t *iptr = src->data[i];
342  optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
343  (padleft >> x_shift);
344  memcpy(optr, iptr, (width - padleft - padright) >> x_shift);
345  iptr += src->linesize[i];
346  optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
347  (dst->linesize[i] - (padright >> x_shift));
348  yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
349  for (y = 0; y < yheight; y++) {
350  memset(optr, color[i], (padleft + padright) >> x_shift);
351  memcpy(optr + ((padleft + padright) >> x_shift), iptr,
352  (width - padleft - padright) >> x_shift);
353  iptr += src->linesize[i];
354  optr += dst->linesize[i];
355  }
356  }
357 
358  if (padbottom || padright) {
359  optr = dst->data[i] + dst->linesize[i] *
360  ((height - padbottom) >> y_shift) - (padright >> x_shift);
361  memset(optr, color[i],dst->linesize[i] *
362  (padbottom >> y_shift) + (padright >> x_shift));
363  }
364  }
365  return 0;
366 }
367 
368 #if !HAVE_MMX_EXTERNAL
369 /* filter parameters: [-1 4 2 4 -1] // 8 */
370 static void deinterlace_line_c(uint8_t *dst,
371  const uint8_t *lum_m4, const uint8_t *lum_m3,
372  const uint8_t *lum_m2, const uint8_t *lum_m1,
373  const uint8_t *lum,
374  int size)
375 {
377  int sum;
378 
379  for(;size > 0;size--) {
380  sum = -lum_m4[0];
381  sum += lum_m3[0] << 2;
382  sum += lum_m2[0] << 1;
383  sum += lum_m1[0] << 2;
384  sum += -lum[0];
385  dst[0] = cm[(sum + 4) >> 3];
386  lum_m4++;
387  lum_m3++;
388  lum_m2++;
389  lum_m1++;
390  lum++;
391  dst++;
392  }
393 }
394 
395 static void deinterlace_line_inplace_c(uint8_t *lum_m4, uint8_t *lum_m3,
396  uint8_t *lum_m2, uint8_t *lum_m1,
397  uint8_t *lum, int size)
398 {
400  int sum;
401 
402  for(;size > 0;size--) {
403  sum = -lum_m4[0];
404  sum += lum_m3[0] << 2;
405  sum += lum_m2[0] << 1;
406  lum_m4[0]=lum_m2[0];
407  sum += lum_m1[0] << 2;
408  sum += -lum[0];
409  lum_m2[0] = cm[(sum + 4) >> 3];
410  lum_m4++;
411  lum_m3++;
412  lum_m2++;
413  lum_m1++;
414  lum++;
415  }
416 }
417 #endif /* !HAVE_MMX_EXTERNAL */
418 
419 /* deinterlacing : 2 temporal taps, 3 spatial taps linear filter. The
420  top field is copied as is, but the bottom field is deinterlaced
421  against the top field. */
422 static void deinterlace_bottom_field(uint8_t *dst, int dst_wrap,
423  const uint8_t *src1, int src_wrap,
424  int width, int height)
425 {
426  const uint8_t *src_m2, *src_m1, *src_0, *src_p1, *src_p2;
427  int y;
428 
429  src_m2 = src1;
430  src_m1 = src1;
431  src_0=&src_m1[src_wrap];
432  src_p1=&src_0[src_wrap];
433  src_p2=&src_p1[src_wrap];
434  for(y=0;y<(height-2);y+=2) {
435  memcpy(dst,src_m1,width);
436  dst += dst_wrap;
437  deinterlace_line(dst,src_m2,src_m1,src_0,src_p1,src_p2,width);
438  src_m2 = src_0;
439  src_m1 = src_p1;
440  src_0 = src_p2;
441  src_p1 += 2*src_wrap;
442  src_p2 += 2*src_wrap;
443  dst += dst_wrap;
444  }
445  memcpy(dst,src_m1,width);
446  dst += dst_wrap;
447  /* do last line */
448  deinterlace_line(dst,src_m2,src_m1,src_0,src_0,src_0,width);
449 }
450 
451 static void deinterlace_bottom_field_inplace(uint8_t *src1, int src_wrap,
452  int width, int height)
453 {
454  uint8_t *src_m1, *src_0, *src_p1, *src_p2;
455  int y;
456  uint8_t *buf;
457  buf = av_malloc(width);
458 
459  src_m1 = src1;
460  memcpy(buf,src_m1,width);
461  src_0=&src_m1[src_wrap];
462  src_p1=&src_0[src_wrap];
463  src_p2=&src_p1[src_wrap];
464  for(y=0;y<(height-2);y+=2) {
465  deinterlace_line_inplace(buf,src_m1,src_0,src_p1,src_p2,width);
466  src_m1 = src_p1;
467  src_0 = src_p2;
468  src_p1 += 2*src_wrap;
469  src_p2 += 2*src_wrap;
470  }
471  /* do last line */
472  deinterlace_line_inplace(buf,src_m1,src_0,src_0,src_0,width);
473  av_free(buf);
474 }
475 
477  enum AVPixelFormat pix_fmt, int width, int height)
478 {
479  int i;
480 
481  if (pix_fmt != AV_PIX_FMT_YUV420P &&
482  pix_fmt != AV_PIX_FMT_YUVJ420P &&
483  pix_fmt != AV_PIX_FMT_YUV422P &&
484  pix_fmt != AV_PIX_FMT_YUVJ422P &&
485  pix_fmt != AV_PIX_FMT_YUV444P &&
486  pix_fmt != AV_PIX_FMT_YUV411P &&
487  pix_fmt != AV_PIX_FMT_GRAY8)
488  return -1;
489  if ((width & 3) != 0 || (height & 3) != 0)
490  return -1;
491 
492  for(i=0;i<3;i++) {
493  if (i == 1) {
494  switch(pix_fmt) {
495  case AV_PIX_FMT_YUVJ420P:
496  case AV_PIX_FMT_YUV420P:
497  width >>= 1;
498  height >>= 1;
499  break;
500  case AV_PIX_FMT_YUV422P:
501  case AV_PIX_FMT_YUVJ422P:
502  width >>= 1;
503  break;
504  case AV_PIX_FMT_YUV411P:
505  width >>= 2;
506  break;
507  default:
508  break;
509  }
510  if (pix_fmt == AV_PIX_FMT_GRAY8) {
511  break;
512  }
513  }
514  if (src == dst) {
516  width, height);
517  } else {
518  deinterlace_bottom_field(dst->data[i],dst->linesize[i],
519  src->data[i], src->linesize[i],
520  width, height);
521  }
522  }
523  emms_c();
524  return 0;
525 }