FFmpeg  4.4.4
xcbgrab.c
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1 /*
2  * XCB input grabber
3  * Copyright (C) 2014 Luca Barbato <lu_zero@gentoo.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "config.h"
23 
24 #include <stdlib.h>
25 #include <string.h>
26 #include <xcb/xcb.h>
27 
28 #if CONFIG_LIBXCB_XFIXES
29 #include <xcb/xfixes.h>
30 #endif
31 
32 #if CONFIG_LIBXCB_SHM
33 #include <sys/shm.h>
34 #include <xcb/shm.h>
35 #endif
36 
37 #if CONFIG_LIBXCB_SHAPE
38 #include <xcb/shape.h>
39 #endif
40 
41 #include "libavutil/internal.h"
42 #include "libavutil/mathematics.h"
43 #include "libavutil/opt.h"
44 #include "libavutil/parseutils.h"
45 #include "libavutil/time.h"
46 
47 #include "libavformat/avformat.h"
48 #include "libavformat/internal.h"
49 
50 typedef struct XCBGrabContext {
51  const AVClass *class;
52 
53  xcb_connection_t *conn;
54  xcb_screen_t *screen;
55  xcb_window_t window;
56 #if CONFIG_LIBXCB_SHM
57  AVBufferPool *shm_pool;
58 #endif
59  int64_t time_frame;
61  int64_t frame_duration;
62 
63  xcb_window_t window_id;
64  int x, y;
65  int width, height;
67  int bpp;
68 
73  int centered;
75 
76  const char *framerate;
77 
78  int has_shm;
80 
81 #define FOLLOW_CENTER -1
82 
83 #define OFFSET(x) offsetof(XCBGrabContext, x)
84 #define D AV_OPT_FLAG_DECODING_PARAM
85 static const AVOption options[] = {
86  { "window_id", "Window to capture.", OFFSET(window_id), AV_OPT_TYPE_INT, { .i64 = XCB_NONE }, 0, UINT32_MAX, D },
87  { "x", "Initial x coordinate.", OFFSET(x), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, D },
88  { "y", "Initial y coordinate.", OFFSET(y), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, D },
89  { "grab_x", "Initial x coordinate.", OFFSET(x), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, D },
90  { "grab_y", "Initial y coordinate.", OFFSET(y), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, D },
91  { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL }, 0, 0, D },
92  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc" }, 0, 0, D },
93  { "draw_mouse", "Draw the mouse pointer.", OFFSET(draw_mouse), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, D },
94  { "follow_mouse", "Move the grabbing region when the mouse pointer reaches within specified amount of pixels to the edge of region.",
95  OFFSET(follow_mouse), AV_OPT_TYPE_INT, { .i64 = 0 }, FOLLOW_CENTER, INT_MAX, D, "follow_mouse" },
96  { "centered", "Keep the mouse pointer at the center of grabbing region when following.", 0, AV_OPT_TYPE_CONST, { .i64 = -1 }, INT_MIN, INT_MAX, D, "follow_mouse" },
97  { "show_region", "Show the grabbing region.", OFFSET(show_region), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, D },
98  { "region_border", "Set the region border thickness.", OFFSET(region_border), AV_OPT_TYPE_INT, { .i64 = 3 }, 1, 128, D },
99  { "select_region", "Select the grabbing region graphically using the pointer.", OFFSET(select_region), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, D },
100  { NULL },
101 };
102 
103 static const AVClass xcbgrab_class = {
104  .class_name = "xcbgrab indev",
105  .item_name = av_default_item_name,
106  .option = options,
107  .version = LIBAVUTIL_VERSION_INT,
109 };
110 
112  xcb_query_pointer_reply_t *p,
113  xcb_get_geometry_reply_t *geo)
114 {
115  XCBGrabContext *c = s->priv_data;
116  int x = c->x, y = c->y;
117  int w = c->width, h = c->height, f = c->follow_mouse;
118  int p_x, p_y;
119 
120  if (!p || !geo)
121  return AVERROR(EIO);
122 
123  p_x = p->win_x;
124  p_y = p->win_y;
125 
126  if (f == FOLLOW_CENTER) {
127  x = p_x - w / 2;
128  y = p_y - h / 2;
129  } else {
130  int left = x + f;
131  int right = x + w - f;
132  int top = y + f;
133  int bottom = y + h - f;
134  if (p_x > right) {
135  x += p_x - right;
136  } else if (p_x < left) {
137  x -= left - p_x;
138  }
139  if (p_y > bottom) {
140  y += p_y - bottom;
141  } else if (p_y < top) {
142  y -= top - p_y;
143  }
144  }
145 
146  c->x = FFMIN(FFMAX(0, x), geo->width - w);
147  c->y = FFMIN(FFMAX(0, y), geo->height - h);
148 
149  return 0;
150 }
151 
152 static void xcbgrab_image_reply_free(void *opaque, uint8_t *data)
153 {
154  free(opaque);
155 }
156 
158 {
159  XCBGrabContext *c = s->priv_data;
160  xcb_get_image_cookie_t iq;
161  xcb_get_image_reply_t *img;
162  xcb_drawable_t drawable = c->window_id;
163  xcb_generic_error_t *e = NULL;
164  uint8_t *data;
165  int length;
166 
167  iq = xcb_get_image(c->conn, XCB_IMAGE_FORMAT_Z_PIXMAP, drawable,
168  c->x, c->y, c->width, c->height, ~0);
169 
170  img = xcb_get_image_reply(c->conn, iq, &e);
171 
172  if (e) {
174  "Cannot get the image data "
175  "event_error: response_type:%u error_code:%u "
176  "sequence:%u resource_id:%u minor_code:%u major_code:%u.\n",
177  e->response_type, e->error_code,
178  e->sequence, e->resource_id, e->minor_code, e->major_code);
179  free(e);
180  return AVERROR(EACCES);
181  }
182 
183  if (!img)
184  return AVERROR(EAGAIN);
185 
186  data = xcb_get_image_data(img);
187  length = xcb_get_image_data_length(img);
188 
190  if (!pkt->buf) {
191  free(img);
192  return AVERROR(ENOMEM);
193  }
194 
195  pkt->data = data;
196  pkt->size = length;
197 
198  return 0;
199 }
200 
202 {
203  XCBGrabContext *c = s->priv_data;
204  int64_t curtime, delay;
205 
206  c->time_frame += c->frame_duration;
207 
208  for (;;) {
209  curtime = av_gettime_relative();
210  delay = c->time_frame - curtime;
211  if (delay <= 0)
212  break;
213  av_usleep(delay);
214  }
215 
216  return curtime;
217 }
218 
219 #if CONFIG_LIBXCB_SHM
220 static int check_shm(xcb_connection_t *conn)
221 {
222  xcb_shm_query_version_cookie_t cookie = xcb_shm_query_version(conn);
223  xcb_shm_query_version_reply_t *reply;
224 
225  reply = xcb_shm_query_version_reply(conn, cookie, NULL);
226  if (reply) {
227  free(reply);
228  return 1;
229  }
230 
231  return 0;
232 }
233 
234 static void free_shm_buffer(void *opaque, uint8_t *data)
235 {
236  shmdt(data);
237 }
238 
239 static AVBufferRef *allocate_shm_buffer(void *opaque, buffer_size_t size)
240 {
241  xcb_connection_t *conn = opaque;
242  xcb_shm_seg_t segment;
243  AVBufferRef *ref;
244  uint8_t *data;
245  int id;
246 
247  id = shmget(IPC_PRIVATE, size, IPC_CREAT | 0777);
248  if (id == -1)
249  return NULL;
250 
251  segment = xcb_generate_id(conn);
252  xcb_shm_attach(conn, segment, id, 0);
253  data = shmat(id, NULL, 0);
254  shmctl(id, IPC_RMID, 0);
255  if ((intptr_t)data == -1 || !data)
256  return NULL;
257 
258  ref = av_buffer_create(data, size, free_shm_buffer, (void *)(ptrdiff_t)segment, 0);
259  if (!ref)
260  shmdt(data);
261 
262  return ref;
263 }
264 
265 static int xcbgrab_frame_shm(AVFormatContext *s, AVPacket *pkt)
266 {
267  XCBGrabContext *c = s->priv_data;
268  xcb_shm_get_image_cookie_t iq;
269  xcb_shm_get_image_reply_t *img;
270  xcb_drawable_t drawable = c->window_id;
271  xcb_generic_error_t *e = NULL;
272  AVBufferRef *buf;
273  xcb_shm_seg_t segment;
274 
275  buf = av_buffer_pool_get(c->shm_pool);
276  if (!buf) {
277  av_log(s, AV_LOG_ERROR, "Could not get shared memory buffer.\n");
278  return AVERROR(ENOMEM);
279  }
280  segment = (xcb_shm_seg_t)av_buffer_pool_buffer_get_opaque(buf);
281 
282  iq = xcb_shm_get_image(c->conn, drawable,
283  c->x, c->y, c->width, c->height, ~0,
284  XCB_IMAGE_FORMAT_Z_PIXMAP, segment, 0);
285  img = xcb_shm_get_image_reply(c->conn, iq, &e);
286 
287  xcb_flush(c->conn);
288 
289  if (e) {
291  "Cannot get the image data "
292  "event_error: response_type:%u error_code:%u "
293  "sequence:%u resource_id:%u minor_code:%u major_code:%u.\n",
294  e->response_type, e->error_code,
295  e->sequence, e->resource_id, e->minor_code, e->major_code);
296 
297  free(e);
298  av_buffer_unref(&buf);
299  return AVERROR(EACCES);
300  }
301 
302  free(img);
303 
304  pkt->buf = buf;
305  pkt->data = buf->data;
306  pkt->size = c->frame_size;
307 
308  return 0;
309 }
310 #endif /* CONFIG_LIBXCB_SHM */
311 
312 #if CONFIG_LIBXCB_XFIXES
313 static int check_xfixes(xcb_connection_t *conn)
314 {
315  xcb_xfixes_query_version_cookie_t cookie;
316  xcb_xfixes_query_version_reply_t *reply;
317 
318  cookie = xcb_xfixes_query_version(conn, XCB_XFIXES_MAJOR_VERSION,
319  XCB_XFIXES_MINOR_VERSION);
320  reply = xcb_xfixes_query_version_reply(conn, cookie, NULL);
321 
322  if (reply) {
323  free(reply);
324  return 1;
325  }
326  return 0;
327 }
328 
329 #define BLEND(target, source, alpha) \
330  (target) + ((source) * (255 - (alpha)) + 255 / 2) / 255
331 
332 static void xcbgrab_draw_mouse(AVFormatContext *s, AVPacket *pkt,
333  xcb_query_pointer_reply_t *p,
334  xcb_get_geometry_reply_t *geo,
335  int win_x, int win_y)
336 {
337  XCBGrabContext *gr = s->priv_data;
338  uint32_t *cursor;
339  uint8_t *image = pkt->data;
340  int stride = gr->bpp / 8;
341  xcb_xfixes_get_cursor_image_cookie_t cc;
342  xcb_xfixes_get_cursor_image_reply_t *ci;
343  int cx, cy, x, y, w, h, c_off, i_off;
344 
345  cc = xcb_xfixes_get_cursor_image(gr->conn);
346  ci = xcb_xfixes_get_cursor_image_reply(gr->conn, cc, NULL);
347  if (!ci)
348  return;
349 
350  cursor = xcb_xfixes_get_cursor_image_cursor_image(ci);
351  if (!cursor)
352  return;
353 
354  cx = ci->x - ci->xhot;
355  cy = ci->y - ci->yhot;
356 
357  x = FFMAX(cx, win_x + gr->x);
358  y = FFMAX(cy, win_y + gr->y);
359 
360  w = FFMIN(cx + ci->width, win_x + gr->x + gr->width) - x;
361  h = FFMIN(cy + ci->height, win_y + gr->y + gr->height) - y;
362 
363  c_off = x - cx;
364  i_off = x - gr->x - win_x;
365 
366  cursor += (y - cy) * ci->width;
367  image += (y - gr->y - win_y) * gr->width * stride;
368 
369  for (y = 0; y < h; y++) {
370  cursor += c_off;
371  image += i_off * stride;
372  for (x = 0; x < w; x++, cursor++, image += stride) {
373  int r, g, b, a;
374 
375  r = *cursor & 0xff;
376  g = (*cursor >> 8) & 0xff;
377  b = (*cursor >> 16) & 0xff;
378  a = (*cursor >> 24) & 0xff;
379 
380  if (!a)
381  continue;
382 
383  if (a == 255) {
384  image[0] = r;
385  image[1] = g;
386  image[2] = b;
387  } else {
388  image[0] = BLEND(r, image[0], a);
389  image[1] = BLEND(g, image[1], a);
390  image[2] = BLEND(b, image[2], a);
391  }
392 
393  }
394  cursor += ci->width - w - c_off;
395  image += (gr->width - w - i_off) * stride;
396  }
397 
398  free(ci);
399 }
400 #endif /* CONFIG_LIBXCB_XFIXES */
401 
402 static void xcbgrab_update_region(AVFormatContext *s, int win_x, int win_y)
403 {
404  XCBGrabContext *c = s->priv_data;
405  const uint32_t args[] = { win_x + c->x - c->region_border,
406  win_y + c->y - c->region_border };
407 
408  xcb_configure_window(c->conn,
409  c->window,
410  XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y,
411  args);
412 }
413 
415 {
416  XCBGrabContext *c = s->priv_data;
417  xcb_query_pointer_cookie_t pc;
418  xcb_get_geometry_cookie_t gc;
419  xcb_translate_coordinates_cookie_t tc;
420  xcb_query_pointer_reply_t *p = NULL;
421  xcb_get_geometry_reply_t *geo = NULL;
422  xcb_translate_coordinates_reply_t *translate = NULL;
423  int ret = 0;
424  int64_t pts;
425  int win_x = 0, win_y = 0;
426 
427  wait_frame(s, pkt);
428  pts = av_gettime();
429 
430  if (c->follow_mouse || c->draw_mouse) {
431  pc = xcb_query_pointer(c->conn, c->window_id);
432  gc = xcb_get_geometry(c->conn, c->window_id);
433  p = xcb_query_pointer_reply(c->conn, pc, NULL);
434  if (!p) {
435  av_log(s, AV_LOG_ERROR, "Failed to query xcb pointer\n");
436  return AVERROR_EXTERNAL;
437  }
438  geo = xcb_get_geometry_reply(c->conn, gc, NULL);
439  if (!geo) {
440  av_log(s, AV_LOG_ERROR, "Failed to get xcb geometry\n");
441  free(p);
442  return AVERROR_EXTERNAL;
443  }
444  }
445  if (c->window_id != c->screen->root) {
446  tc = xcb_translate_coordinates(c->conn, c->window_id, c->screen->root, 0, 0);
447  translate = xcb_translate_coordinates_reply(c->conn, tc, NULL);
448  if (!translate) {
449  free(p);
450  free(geo);
451  av_log(s, AV_LOG_ERROR, "Failed to translate xcb geometry\n");
452  return AVERROR_EXTERNAL;
453  }
454  win_x = translate->dst_x;
455  win_y = translate->dst_y;
456  free(translate);
457  }
458 
459  if (c->follow_mouse && p->same_screen)
460  xcbgrab_reposition(s, p, geo);
461 
462  if (c->show_region)
463  xcbgrab_update_region(s, win_x, win_y);
464 
465 #if CONFIG_LIBXCB_SHM
466  if (c->has_shm && xcbgrab_frame_shm(s, pkt) < 0) {
467  av_log(s, AV_LOG_WARNING, "Continuing without shared memory.\n");
468  c->has_shm = 0;
469  }
470 #endif
471  if (!c->has_shm)
472  ret = xcbgrab_frame(s, pkt);
473  pkt->dts = pkt->pts = pts;
474  pkt->duration = c->frame_duration;
475 
476 #if CONFIG_LIBXCB_XFIXES
477  if (ret >= 0 && c->draw_mouse && p->same_screen)
478  xcbgrab_draw_mouse(s, pkt, p, geo, win_x, win_y);
479 #endif
480 
481  free(p);
482  free(geo);
483 
484  return ret;
485 }
486 
488 {
489  XCBGrabContext *ctx = s->priv_data;
490 
491 #if CONFIG_LIBXCB_SHM
492  av_buffer_pool_uninit(&ctx->shm_pool);
493 #endif
494 
495  xcb_disconnect(ctx->conn);
496 
497  return 0;
498 }
499 
500 static xcb_screen_t *get_screen(const xcb_setup_t *setup, int screen_num)
501 {
502  xcb_screen_iterator_t it = xcb_setup_roots_iterator(setup);
503  xcb_screen_t *screen = NULL;
504 
505  for (; it.rem > 0; xcb_screen_next (&it)) {
506  if (!screen_num) {
507  screen = it.data;
508  break;
509  }
510 
511  screen_num--;
512  }
513 
514  return screen;
515 }
516 
518  int *pix_fmt, int *bpp)
519 {
520  XCBGrabContext *c = s->priv_data;
521  const xcb_setup_t *setup = xcb_get_setup(c->conn);
522  const xcb_format_t *fmt = xcb_setup_pixmap_formats(setup);
523  int length = xcb_setup_pixmap_formats_length(setup);
524 
525  *pix_fmt = 0;
526 
527  while (length--) {
528  if (fmt->depth == depth) {
529  switch (depth) {
530  case 32:
531  if (fmt->bits_per_pixel == 32)
532  *pix_fmt = setup->image_byte_order == XCB_IMAGE_ORDER_LSB_FIRST ?
534  break;
535  case 24:
536  if (fmt->bits_per_pixel == 32)
537  *pix_fmt = setup->image_byte_order == XCB_IMAGE_ORDER_LSB_FIRST ?
539  else if (fmt->bits_per_pixel == 24)
540  *pix_fmt = setup->image_byte_order == XCB_IMAGE_ORDER_LSB_FIRST ?
542  break;
543  case 16:
544  if (fmt->bits_per_pixel == 16)
545  *pix_fmt = setup->image_byte_order == XCB_IMAGE_ORDER_LSB_FIRST ?
547  break;
548  case 15:
549  if (fmt->bits_per_pixel == 16)
550  *pix_fmt = setup->image_byte_order == XCB_IMAGE_ORDER_LSB_FIRST ?
552  break;
553  case 8:
554  if (fmt->bits_per_pixel == 8)
556  break;
557  }
558  }
559 
560  if (*pix_fmt) {
561  *bpp = fmt->bits_per_pixel;
562  return 0;
563  }
564 
565  fmt++;
566  }
567  avpriv_report_missing_feature(s, "Mapping this pixmap format");
568 
569  return AVERROR_PATCHWELCOME;
570 }
571 
573 {
574  XCBGrabContext *c = s->priv_data;
576  xcb_get_geometry_cookie_t gc;
577  xcb_get_geometry_reply_t *geo;
578  int64_t frame_size_bits;
579  int ret;
580 
581  if (!st)
582  return AVERROR(ENOMEM);
583 
584  ret = av_parse_video_rate(&st->avg_frame_rate, c->framerate);
585  if (ret < 0)
586  return ret;
587 
588  avpriv_set_pts_info(st, 64, 1, 1000000);
589 
590  gc = xcb_get_geometry(c->conn, c->window_id);
591  geo = xcb_get_geometry_reply(c->conn, gc, NULL);
592  if (!geo) {
593  av_log(s, AV_LOG_ERROR, "Can't find window '0x%x', aborting.\n", c->window_id);
594  return AVERROR_EXTERNAL;
595  }
596 
597  if (!c->width || !c->height) {
598  c->width = geo->width;
599  c->height = geo->height;
600  }
601 
602  if (c->x + c->width > geo->width ||
603  c->y + c->height > geo->height) {
605  "Capture area %dx%d at position %d.%d "
606  "outside the screen size %dx%d\n",
607  c->width, c->height,
608  c->x, c->y,
609  geo->width, geo->height);
610  free(geo);
611  return AVERROR(EINVAL);
612  }
613 
614  c->time_base = (AVRational){ st->avg_frame_rate.den,
615  st->avg_frame_rate.num };
616  c->frame_duration = av_rescale_q(1, c->time_base, AV_TIME_BASE_Q);
617  c->time_frame = av_gettime_relative();
618 
619  ret = pixfmt_from_pixmap_format(s, geo->depth, &st->codecpar->format, &c->bpp);
620  free(geo);
621  if (ret < 0)
622  return ret;
623 
624  frame_size_bits = (int64_t)c->width * c->height * c->bpp;
625  if (frame_size_bits / 8 + AV_INPUT_BUFFER_PADDING_SIZE > INT_MAX) {
626  av_log(s, AV_LOG_ERROR, "Captured area is too large\n");
627  return AVERROR_PATCHWELCOME;
628  }
629  c->frame_size = frame_size_bits / 8;
630 
631 #if CONFIG_LIBXCB_SHM
632  c->shm_pool = av_buffer_pool_init2(c->frame_size + AV_INPUT_BUFFER_PADDING_SIZE,
633  c->conn, allocate_shm_buffer, NULL);
634  if (!c->shm_pool)
635  return AVERROR(ENOMEM);
636 #endif
637 
640  st->codecpar->width = c->width;
641  st->codecpar->height = c->height;
642  st->codecpar->bit_rate = av_rescale(frame_size_bits, st->avg_frame_rate.num, st->avg_frame_rate.den);
643 
644  return ret;
645 }
646 
648 {
649  XCBGrabContext *c = s->priv_data;
650  xcb_gcontext_t gc = xcb_generate_id(c->conn);
651  uint32_t mask = XCB_GC_FOREGROUND |
652  XCB_GC_BACKGROUND |
653  XCB_GC_LINE_WIDTH |
654  XCB_GC_LINE_STYLE |
655  XCB_GC_FILL_STYLE;
656  uint32_t values[] = { c->screen->black_pixel,
657  c->screen->white_pixel,
658  c->region_border,
659  XCB_LINE_STYLE_DOUBLE_DASH,
660  XCB_FILL_STYLE_SOLID };
661  xcb_rectangle_t r = { 1, 1,
662  c->width + c->region_border * 2 - 3,
663  c->height + c->region_border * 2 - 3 };
664 
665  xcb_create_gc(c->conn, gc, c->window, mask, values);
666 
667  xcb_poly_rectangle(c->conn, c->window, gc, 1, &r);
668 }
669 
671 {
672  XCBGrabContext *c = s->priv_data;
673  uint32_t mask = XCB_CW_OVERRIDE_REDIRECT | XCB_CW_EVENT_MASK;
674  uint32_t values[] = { 1,
675  XCB_EVENT_MASK_EXPOSURE |
676  XCB_EVENT_MASK_STRUCTURE_NOTIFY };
677  av_unused xcb_rectangle_t rect = { 0, 0, c->width, c->height };
678 
679  c->window = xcb_generate_id(c->conn);
680 
681  xcb_create_window(c->conn, XCB_COPY_FROM_PARENT,
682  c->window,
683  c->screen->root,
684  c->x - c->region_border,
685  c->y - c->region_border,
686  c->width + c->region_border * 2,
687  c->height + c->region_border * 2,
688  0,
689  XCB_WINDOW_CLASS_INPUT_OUTPUT,
690  XCB_COPY_FROM_PARENT,
691  mask, values);
692 
693 #if CONFIG_LIBXCB_SHAPE
694  xcb_shape_rectangles(c->conn, XCB_SHAPE_SO_SUBTRACT,
695  XCB_SHAPE_SK_BOUNDING, XCB_CLIP_ORDERING_UNSORTED,
696  c->window,
697  c->region_border, c->region_border,
698  1, &rect);
699 #endif
700 
701  xcb_map_window(c->conn, c->window);
702 
703  draw_rectangle(s);
704 }
705 
706 #define CROSSHAIR_CURSOR 34
707 
708 static xcb_rectangle_t rectangle_from_corners(xcb_point_t *corner_a,
709  xcb_point_t *corner_b)
710 {
711  xcb_rectangle_t rectangle;
712  rectangle.x = FFMIN(corner_a->x, corner_b->x);
713  rectangle.y = FFMIN(corner_a->y, corner_b->y);
714  rectangle.width = FFABS(corner_a->x - corner_b->x);
715  rectangle.height = FFABS(corner_a->y - corner_b->y);
716  return rectangle;
717 }
718 
720 {
721  XCBGrabContext *c = s->priv_data;
722  xcb_connection_t *conn = c->conn;
723  xcb_screen_t *screen = c->screen;
724 
725  int ret = 0, done = 0, was_pressed = 0;
726  xcb_cursor_t cursor;
727  xcb_font_t cursor_font;
728  xcb_point_t press_position;
729  xcb_generic_event_t *event;
730  xcb_rectangle_t rectangle = { 0 };
731  xcb_grab_pointer_reply_t *reply;
732  xcb_grab_pointer_cookie_t cookie;
733 
734  xcb_window_t root_window = screen->root;
735  xcb_gcontext_t gc = xcb_generate_id(conn);
736  uint32_t mask = XCB_GC_FUNCTION | XCB_GC_SUBWINDOW_MODE;
737  uint32_t values[] = { XCB_GX_INVERT, XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS };
738  xcb_create_gc(conn, gc, root_window, mask, values);
739 
740  cursor_font = xcb_generate_id(conn);
741  xcb_open_font(conn, cursor_font, strlen("cursor"), "cursor");
742  cursor = xcb_generate_id(conn);
743  xcb_create_glyph_cursor(conn, cursor, cursor_font, cursor_font,
744  CROSSHAIR_CURSOR, CROSSHAIR_CURSOR + 1, 0, 0, 0,
745  0xFFFF, 0xFFFF, 0xFFFF);
746  cookie = xcb_grab_pointer(conn, 0, root_window,
747  XCB_EVENT_MASK_BUTTON_PRESS |
748  XCB_EVENT_MASK_BUTTON_RELEASE |
749  XCB_EVENT_MASK_BUTTON_MOTION,
750  XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC,
751  root_window, cursor, XCB_CURRENT_TIME);
752  reply = xcb_grab_pointer_reply(conn, cookie, NULL);
753  if (!reply || reply->status != XCB_GRAB_STATUS_SUCCESS) {
755  "Failed to select region. Could not grab pointer.\n");
756  ret = AVERROR(EIO);
757  free(reply);
758  goto fail;
759  }
760  free(reply);
761 
762  xcb_grab_server(conn);
763 
764  while (!done && (event = xcb_wait_for_event(conn))) {
765  switch (event->response_type & ~0x80) {
766  case XCB_BUTTON_PRESS: {
767  xcb_button_press_event_t *press = (xcb_button_press_event_t *)event;
768  press_position = (xcb_point_t){ press->event_x, press->event_y };
769  rectangle.x = press_position.x;
770  rectangle.y = press_position.y;
771  xcb_poly_rectangle(conn, root_window, gc, 1, &rectangle);
772  was_pressed = 1;
773  break;
774  }
775  case XCB_MOTION_NOTIFY: {
776  if (was_pressed) {
777  xcb_motion_notify_event_t *motion =
778  (xcb_motion_notify_event_t *)event;
779  xcb_point_t cursor_position = { motion->event_x, motion->event_y };
780  xcb_poly_rectangle(conn, root_window, gc, 1, &rectangle);
781  rectangle = rectangle_from_corners(&press_position, &cursor_position);
782  xcb_poly_rectangle(conn, root_window, gc, 1, &rectangle);
783  }
784  break;
785  }
786  case XCB_BUTTON_RELEASE: {
787  xcb_poly_rectangle(conn, root_window, gc, 1, &rectangle);
788  done = 1;
789  break;
790  }
791  default:
792  break;
793  }
794  xcb_flush(conn);
795  free(event);
796  }
797  c->width = rectangle.width;
798  c->height = rectangle.height;
799  if (c->width && c->height) {
800  c->x = rectangle.x;
801  c->y = rectangle.y;
802  } else {
803  c->x = 0;
804  c->y = 0;
805  }
806  xcb_ungrab_server(conn);
807  xcb_ungrab_pointer(conn, XCB_CURRENT_TIME);
808  xcb_flush(conn);
809 
810 fail:
811  xcb_free_cursor(conn, cursor);
812  xcb_close_font(conn, cursor_font);
813  xcb_free_gc(conn, gc);
814  return ret;
815 }
816 
818 {
819  XCBGrabContext *c = s->priv_data;
820  int screen_num, ret;
821  const xcb_setup_t *setup;
822  char *display_name = av_strdup(s->url);
823 
824  if (!display_name)
825  return AVERROR(ENOMEM);
826 
827  if (!sscanf(s->url, "%[^+]+%d,%d", display_name, &c->x, &c->y)) {
828  *display_name = 0;
829  sscanf(s->url, "+%d,%d", &c->x, &c->y);
830  }
831 
832  c->conn = xcb_connect(display_name[0] ? display_name : NULL, &screen_num);
833  av_freep(&display_name);
834 
835  if ((ret = xcb_connection_has_error(c->conn))) {
836  av_log(s, AV_LOG_ERROR, "Cannot open display %s, error %d.\n",
837  s->url[0] ? s->url : "default", ret);
838  return AVERROR(EIO);
839  }
840 
841  setup = xcb_get_setup(c->conn);
842 
843  c->screen = get_screen(setup, screen_num);
844  if (!c->screen) {
845  av_log(s, AV_LOG_ERROR, "The screen %d does not exist.\n",
846  screen_num);
848  return AVERROR(EIO);
849  }
850 
851  if (c->window_id == XCB_NONE)
852  c->window_id = c->screen->root;
853  else {
854  if (c->select_region) {
855  av_log(s, AV_LOG_WARNING, "select_region ignored with window_id.\n");
856  c->select_region = 0;
857  }
858  if (c->follow_mouse) {
859  av_log(s, AV_LOG_WARNING, "follow_mouse ignored with window_id.\n");
860  c->follow_mouse = 0;
861  }
862  }
863 
864  if (c->select_region) {
865  ret = select_region(s);
866  if (ret < 0) {
868  return ret;
869  }
870  }
871 
872  ret = create_stream(s);
873 
874  if (ret < 0) {
876  return ret;
877  }
878 
879 #if CONFIG_LIBXCB_SHM
880  c->has_shm = check_shm(c->conn);
881 #endif
882 
883 #if CONFIG_LIBXCB_XFIXES
884  if (c->draw_mouse) {
885  if (!(c->draw_mouse = check_xfixes(c->conn))) {
887  "XFixes not available, cannot draw the mouse.\n");
888  }
889  if (c->bpp < 24) {
890  avpriv_report_missing_feature(s, "%d bits per pixel screen",
891  c->bpp);
892  c->draw_mouse = 0;
893  }
894  }
895 #endif
896 
897  if (c->show_region)
898  setup_window(s);
899 
900  return 0;
901 }
902 
904  .name = "x11grab",
905  .long_name = NULL_IF_CONFIG_SMALL("X11 screen capture, using XCB"),
906  .priv_data_size = sizeof(XCBGrabContext),
910  .flags = AVFMT_NOFILE,
911  .priv_class = &xcbgrab_class,
912 };
#define av_unused
Definition: attributes.h:131
#define av_cold
Definition: attributes.h:88
uint8_t
Main libavformat public API header.
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:458
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define f(width, name)
Definition: cbs_vp9.c:255
#define fail()
Definition: checkasm.h:133
#define FFMIN(a, b)
Definition: common.h:105
#define FFMAX(a, b)
Definition: common.h:103
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
#define NULL
Definition: coverity.c:32
static enum AVPixelFormat pix_fmt
enum AVCodecID id
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
@ AV_OPT_TYPE_IMAGE_SIZE
offset must point to two consecutive integers
Definition: opt.h:235
@ AV_OPT_TYPE_CONST
Definition: opt.h:234
@ AV_OPT_TYPE_INT
Definition: opt.h:225
@ AV_OPT_TYPE_BOOL
Definition: opt.h:242
@ AV_OPT_TYPE_STRING
Definition: opt.h:229
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:62
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding.
Definition: avcodec.h:215
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it.
Definition: buffer.c:125
AVBufferRef * av_buffer_create(uint8_t *data, buffer_size_t size, void(*free)(void *opaque, uint8_t *data), void *opaque, int flags)
Create an AVBuffer from an existing array.
Definition: buffer.c:29
AVBufferRef * av_buffer_pool_get(AVBufferPool *pool)
Allocate a new AVBuffer, reusing an old buffer from the pool when available.
Definition: buffer.c:373
AVBufferPool * av_buffer_pool_init2(buffer_size_t size, void *opaque, AVBufferRef *(*alloc)(void *opaque, buffer_size_t size), void(*pool_free)(void *opaque))
Allocate and initialize a buffer pool with a more complex allocator.
Definition: buffer.c:245
void av_buffer_pool_uninit(AVBufferPool **ppool)
Mark the pool as being available for freeing.
Definition: buffer.c:308
void * av_buffer_pool_buffer_get_opaque(AVBufferRef *ref)
Query the original opaque parameter of an allocated buffer in the pool.
Definition: buffer.c:398
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:57
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:253
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4945
common internal API header
int buffer_size_t
Definition: internal.h:306
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
uint8_t w
Definition: llviddspenc.c:39
@ AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT
Definition: log.h:42
static const uint16_t mask[17]
Definition: lzw.c:38
int stride
Definition: mace.c:144
const char data[16]
Definition: mxf.c:142
AVOptions.
int av_parse_video_rate(AVRational *rate, const char *arg)
Parse str and store the detected values in *rate.
Definition: parseutils.c:179
misc parsing utilities
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
@ AV_PIX_FMT_BGR0
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
@ AV_PIX_FMT_RGB555BE
packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), big-endian , X=unused/undefined
Definition: pixfmt.h:107
@ AV_PIX_FMT_RGB8
packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
Definition: pixfmt.h:86
@ AV_PIX_FMT_RGB565LE
packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), little-endian
Definition: pixfmt.h:106
@ AV_PIX_FMT_RGB555LE
packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), little-endian, X=unused/undefined
Definition: pixfmt.h:108
@ AV_PIX_FMT_RGB565BE
packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), big-endian
Definition: pixfmt.h:105
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
@ AV_PIX_FMT_0RGB
packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined
Definition: pixfmt.h:237
#define tc
Definition: regdef.h:69
The buffer pool.
A reference to a data buffer.
Definition: buffer.h:84
uint8_t * data
The data buffer.
Definition: buffer.h:92
Describe the class of an AVClass context structure.
Definition: log.h:67
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
int width
Video only.
Definition: codec_par.h:126
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
AVOption.
Definition: opt.h:248
This structure stores compressed data.
Definition: packet.h:346
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: packet.h:352
int size
Definition: packet.h:370
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:368
uint8_t * data
Definition: packet.h:369
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int num
Numerator.
Definition: rational.h:59
int den
Denominator.
Definition: rational.h:60
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:946
const char * framerate
Definition: xcbgrab.c:76
xcb_connection_t * conn
Definition: xcbgrab.c:53
int draw_mouse
Definition: xcbgrab.c:69
int region_border
Definition: xcbgrab.c:72
xcb_window_t window_id
Definition: xcbgrab.c:63
int select_region
Definition: xcbgrab.c:74
int follow_mouse
Definition: xcbgrab.c:70
int64_t frame_duration
Definition: xcbgrab.c:61
xcb_window_t window
Definition: xcbgrab.c:55
int show_region
Definition: xcbgrab.c:71
AVRational time_base
Definition: xcbgrab.c:60
int centered
Definition: xcbgrab.c:73
int64_t time_frame
Definition: xcbgrab.c:59
xcb_screen_t * screen
Definition: xcbgrab.c:54
int frame_size
Definition: xcbgrab.c:66
Definition: f_ebur128.c:91
Definition: hls.c:68
#define av_freep(p)
#define av_log(a,...)
int framerate
Definition: h264_levels.c:65
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
AVPacket * pkt
Definition: movenc.c:59
AVFormatContext * ctx
Definition: movenc.c:48
#define width
int av_usleep(unsigned usec)
Sleep for a period of time.
Definition: time.c:84
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
static int64_t pts
int size
#define img
const char * b
Definition: vf_curves.c:118
const char * g
Definition: vf_curves.c:117
const char * r
Definition: vf_curves.c:116
if(ret< 0)
Definition: vf_mcdeint.c:282
static double c[64]
static xcb_rectangle_t rectangle_from_corners(xcb_point_t *corner_a, xcb_point_t *corner_b)
Definition: xcbgrab.c:708
static int64_t wait_frame(AVFormatContext *s, AVPacket *pkt)
Definition: xcbgrab.c:201
static void xcbgrab_image_reply_free(void *opaque, uint8_t *data)
Definition: xcbgrab.c:152
#define FOLLOW_CENTER
Definition: xcbgrab.c:81
static xcb_screen_t * get_screen(const xcb_setup_t *setup, int screen_num)
Definition: xcbgrab.c:500
static int select_region(AVFormatContext *s)
Definition: xcbgrab.c:719
static int xcbgrab_reposition(AVFormatContext *s, xcb_query_pointer_reply_t *p, xcb_get_geometry_reply_t *geo)
Definition: xcbgrab.c:111
#define CROSSHAIR_CURSOR
Definition: xcbgrab.c:706
static int xcbgrab_frame(AVFormatContext *s, AVPacket *pkt)
Definition: xcbgrab.c:157
static const AVOption options[]
Definition: xcbgrab.c:85
static void setup_window(AVFormatContext *s)
Definition: xcbgrab.c:670
AVInputFormat ff_xcbgrab_demuxer
Definition: xcbgrab.c:903
static void xcbgrab_update_region(AVFormatContext *s, int win_x, int win_y)
Definition: xcbgrab.c:402
static void draw_rectangle(AVFormatContext *s)
Definition: xcbgrab.c:647
static const AVClass xcbgrab_class
Definition: xcbgrab.c:103
static int xcbgrab_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: xcbgrab.c:414
static int pixfmt_from_pixmap_format(AVFormatContext *s, int depth, int *pix_fmt, int *bpp)
Definition: xcbgrab.c:517
static int create_stream(AVFormatContext *s)
Definition: xcbgrab.c:572
static av_cold int xcbgrab_read_header(AVFormatContext *s)
Definition: xcbgrab.c:817
static av_cold int xcbgrab_read_close(AVFormatContext *s)
Definition: xcbgrab.c:487
#define OFFSET(x)
Definition: xcbgrab.c:83
#define D
Definition: xcbgrab.c:84