imgutils.c
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * Libav is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
24 #include "imgutils.h"
25 #include "internal.h"
26 #include "log.h"
27 #include "pixdesc.h"
28 
29 void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
30  const AVPixFmtDescriptor *pixdesc)
31 {
32  int i;
33  memset(max_pixsteps, 0, 4*sizeof(max_pixsteps[0]));
34  if (max_pixstep_comps)
35  memset(max_pixstep_comps, 0, 4*sizeof(max_pixstep_comps[0]));
36 
37  for (i = 0; i < 4; i++) {
38  const AVComponentDescriptor *comp = &(pixdesc->comp[i]);
39  if ((comp->step_minus1+1) > max_pixsteps[comp->plane]) {
40  max_pixsteps[comp->plane] = comp->step_minus1+1;
41  if (max_pixstep_comps)
42  max_pixstep_comps[comp->plane] = i;
43  }
44  }
45 }
46 
48 {
50  int max_step [4]; /* max pixel step for each plane */
51  int max_step_comp[4]; /* the component for each plane which has the max pixel step */
52  int s;
53 
54  if (desc->flags & PIX_FMT_BITSTREAM)
55  return (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
56 
57  av_image_fill_max_pixsteps(max_step, max_step_comp, desc);
58  s = (max_step_comp[plane] == 1 || max_step_comp[plane] == 2) ? desc->log2_chroma_w : 0;
59  return max_step[plane] * (((width + (1 << s) - 1)) >> s);
60 }
61 
62 int av_image_fill_linesizes(int linesizes[4], enum PixelFormat pix_fmt, int width)
63 {
64  int i;
66  int max_step [4]; /* max pixel step for each plane */
67  int max_step_comp[4]; /* the component for each plane which has the max pixel step */
68 
69  memset(linesizes, 0, 4*sizeof(linesizes[0]));
70 
71  if ((unsigned)pix_fmt >= PIX_FMT_NB || desc->flags & PIX_FMT_HWACCEL)
72  return AVERROR(EINVAL);
73 
74  if (desc->flags & PIX_FMT_BITSTREAM) {
75  if (width > (INT_MAX -7) / (desc->comp[0].step_minus1+1))
76  return AVERROR(EINVAL);
77  linesizes[0] = (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
78  return 0;
79  }
80 
81  av_image_fill_max_pixsteps(max_step, max_step_comp, desc);
82  for (i = 0; i < 4; i++) {
83  int s = (max_step_comp[i] == 1 || max_step_comp[i] == 2) ? desc->log2_chroma_w : 0;
84  int shifted_w = ((width + (1 << s) - 1)) >> s;
85  if (max_step[i] > INT_MAX / shifted_w)
86  return AVERROR(EINVAL);
87  linesizes[i] = max_step[i] * shifted_w;
88  }
89 
90  return 0;
91 }
92 
94  uint8_t *ptr, const int linesizes[4])
95 {
96  int i, total_size, size[4], has_plane[4];
97 
99  memset(data , 0, sizeof(data[0])*4);
100  memset(size , 0, sizeof(size));
101  memset(has_plane, 0, sizeof(has_plane));
102 
103  if ((unsigned)pix_fmt >= PIX_FMT_NB || desc->flags & PIX_FMT_HWACCEL)
104  return AVERROR(EINVAL);
105 
106  data[0] = ptr;
107  if (linesizes[0] > (INT_MAX - 1024) / height)
108  return AVERROR(EINVAL);
109  size[0] = linesizes[0] * height;
110 
111  if (desc->flags & PIX_FMT_PAL) {
112  size[0] = (size[0] + 3) & ~3;
113  data[1] = ptr + size[0]; /* palette is stored here as 256 32 bits words */
114  return size[0] + 256 * 4;
115  }
116 
117  for (i = 0; i < 4; i++)
118  has_plane[desc->comp[i].plane] = 1;
119 
120  total_size = size[0];
121  for (i = 1; i < 4 && has_plane[i]; i++) {
122  int h, s = (i == 1 || i == 2) ? desc->log2_chroma_h : 0;
123  data[i] = data[i-1] + size[i-1];
124  h = (height + (1 << s) - 1) >> s;
125  if (linesizes[i] > INT_MAX / h)
126  return AVERROR(EINVAL);
127  size[i] = h * linesizes[i];
128  if (total_size > INT_MAX - size[i])
129  return AVERROR(EINVAL);
130  total_size += size[i];
131  }
132 
133  return total_size;
134 }
135 
136 int ff_set_systematic_pal2(uint32_t pal[256], enum PixelFormat pix_fmt)
137 {
138  int i;
139 
140  for (i = 0; i < 256; i++) {
141  int r, g, b;
142 
143  switch (pix_fmt) {
144  case PIX_FMT_RGB8:
145  r = (i>>5 )*36;
146  g = ((i>>2)&7)*36;
147  b = (i&3 )*85;
148  break;
149  case PIX_FMT_BGR8:
150  b = (i>>6 )*85;
151  g = ((i>>3)&7)*36;
152  r = (i&7 )*36;
153  break;
154  case PIX_FMT_RGB4_BYTE:
155  r = (i>>3 )*255;
156  g = ((i>>1)&3)*85;
157  b = (i&1 )*255;
158  break;
159  case PIX_FMT_BGR4_BYTE:
160  b = (i>>3 )*255;
161  g = ((i>>1)&3)*85;
162  r = (i&1 )*255;
163  break;
164  case PIX_FMT_GRAY8:
165  r = b = g = i;
166  break;
167  default:
168  return AVERROR(EINVAL);
169  }
170  pal[i] = b + (g<<8) + (r<<16);
171  }
172 
173  return 0;
174 }
175 
176 int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
177  int w, int h, enum PixelFormat pix_fmt, int align)
178 {
179  int i, ret;
180  uint8_t *buf;
181 
182  if ((ret = av_image_check_size(w, h, 0, NULL)) < 0)
183  return ret;
184  if ((ret = av_image_fill_linesizes(linesizes, pix_fmt, w)) < 0)
185  return ret;
186 
187  for (i = 0; i < 4; i++)
188  linesizes[i] = FFALIGN(linesizes[i], align);
189 
190  if ((ret = av_image_fill_pointers(pointers, pix_fmt, h, NULL, linesizes)) < 0)
191  return ret;
192  buf = av_malloc(ret + align);
193  if (!buf)
194  return AVERROR(ENOMEM);
195  if ((ret = av_image_fill_pointers(pointers, pix_fmt, h, buf, linesizes)) < 0) {
196  av_free(buf);
197  return ret;
198  }
200  ff_set_systematic_pal2((uint32_t*)pointers[1], pix_fmt);
201 
202  return ret;
203 }
204 
205 typedef struct ImgUtils {
206  const AVClass *class;
208  void *log_ctx;
209 } ImgUtils;
210 
211 static const AVClass imgutils_class = { "IMGUTILS", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(ImgUtils, log_offset), offsetof(ImgUtils, log_ctx) };
212 
213 int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
214 {
215  ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
216 
217  if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
218  return 0;
219 
220  av_log(&imgutils, AV_LOG_ERROR, "Picture size %ux%u is invalid\n", w, h);
221  return AVERROR(EINVAL);
222 }
223 
224 void av_image_copy_plane(uint8_t *dst, int dst_linesize,
225  const uint8_t *src, int src_linesize,
226  int bytewidth, int height)
227 {
228  if (!dst || !src)
229  return;
230  for (;height > 0; height--) {
231  memcpy(dst, src, bytewidth);
232  dst += dst_linesize;
233  src += src_linesize;
234  }
235 }
236 
237 void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
238  const uint8_t *src_data[4], const int src_linesizes[4],
239  enum PixelFormat pix_fmt, int width, int height)
240 {
242 
243  if (desc->flags & PIX_FMT_HWACCEL)
244  return;
245 
246  if (desc->flags & PIX_FMT_PAL) {
247  av_image_copy_plane(dst_data[0], dst_linesizes[0],
248  src_data[0], src_linesizes[0],
249  width, height);
250  /* copy the palette */
251  memcpy(dst_data[1], src_data[1], 4*256);
252  } else {
253  int i, planes_nb = 0;
254 
255  for (i = 0; i < desc->nb_components; i++)
256  planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
257 
258  for (i = 0; i < planes_nb; i++) {
259  int h = height;
260  int bwidth = av_image_get_linesize(pix_fmt, width, i);
261  if (i == 1 || i == 2) {
262  h= -((-height)>>desc->log2_chroma_h);
263  }
264  av_image_copy_plane(dst_data[i], dst_linesizes[i],
265  src_data[i], src_linesizes[i],
266  bwidth, h);
267  }
268  }
269 }