FFmpeg  4.0
gdigrab.c
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1 /*
2  * GDI video grab interface
3  *
4  * This file is part of FFmpeg.
5  *
6  * Copyright (C) 2013 Calvin Walton <calvin.walton@kepstin.ca>
7  * Copyright (C) 2007-2010 Christophe Gisquet <word1.word2@gmail.com>
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public License
11  * as published by the Free Software Foundation; either version 2.1
12  * of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * GDI frame device demuxer
27  * @author Calvin Walton <calvin.walton@kepstin.ca>
28  * @author Christophe Gisquet <word1.word2@gmail.com>
29  */
30 
31 #include "config.h"
32 #include "libavformat/internal.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/time.h"
35 #include <windows.h>
36 
37 /**
38  * GDI Device Demuxer context
39  */
40 struct gdigrab {
41  const AVClass *class; /**< Class for private options */
42 
43  int frame_size; /**< Size in bytes of the frame pixel data */
44  int header_size; /**< Size in bytes of the DIB header */
45  AVRational time_base; /**< Time base */
46  int64_t time_frame; /**< Current time */
47 
48  int draw_mouse; /**< Draw mouse cursor (private option) */
49  int show_region; /**< Draw border (private option) */
50  AVRational framerate; /**< Capture framerate (private option) */
51  int width; /**< Width of the grab frame (private option) */
52  int height; /**< Height of the grab frame (private option) */
53  int offset_x; /**< Capture x offset (private option) */
54  int offset_y; /**< Capture y offset (private option) */
55 
56  HWND hwnd; /**< Handle of the window for the grab */
57  HDC source_hdc; /**< Source device context */
58  HDC dest_hdc; /**< Destination, source-compatible DC */
59  BITMAPINFO bmi; /**< Information describing DIB format */
60  HBITMAP hbmp; /**< Information on the bitmap captured */
61  void *buffer; /**< The buffer containing the bitmap image data */
62  RECT clip_rect; /**< The subarea of the screen or window to clip */
63 
64  HWND region_hwnd; /**< Handle of the region border window */
65 
67 };
68 
69 #define WIN32_API_ERROR(str) \
70  av_log(s1, AV_LOG_ERROR, str " (error %li)\n", GetLastError())
71 
72 #define REGION_WND_BORDER 3
73 
74 /**
75  * Callback to handle Windows messages for the region outline window.
76  *
77  * In particular, this handles painting the frame rectangle.
78  *
79  * @param hwnd The region outline window handle.
80  * @param msg The Windows message.
81  * @param wparam First Windows message parameter.
82  * @param lparam Second Windows message parameter.
83  * @return 0 success, !0 failure
84  */
85 static LRESULT CALLBACK
86 gdigrab_region_wnd_proc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
87 {
88  PAINTSTRUCT ps;
89  HDC hdc;
90  RECT rect;
91 
92  switch (msg) {
93  case WM_PAINT:
94  hdc = BeginPaint(hwnd, &ps);
95 
96  GetClientRect(hwnd, &rect);
97  FrameRect(hdc, &rect, GetStockObject(BLACK_BRUSH));
98 
99  rect.left++; rect.top++; rect.right--; rect.bottom--;
100  FrameRect(hdc, &rect, GetStockObject(WHITE_BRUSH));
101 
102  rect.left++; rect.top++; rect.right--; rect.bottom--;
103  FrameRect(hdc, &rect, GetStockObject(BLACK_BRUSH));
104 
105  EndPaint(hwnd, &ps);
106  break;
107  default:
108  return DefWindowProc(hwnd, msg, wparam, lparam);
109  }
110  return 0;
111 }
112 
113 /**
114  * Initialize the region outline window.
115  *
116  * @param s1 The format context.
117  * @param gdigrab gdigrab context.
118  * @return 0 success, !0 failure
119  */
120 static int
122 {
123  HWND hwnd;
124  RECT rect = gdigrab->clip_rect;
125  HRGN region = NULL;
126  HRGN region_interior = NULL;
127 
128  DWORD style = WS_POPUP | WS_VISIBLE;
129  DWORD ex = WS_EX_TOOLWINDOW | WS_EX_TOPMOST | WS_EX_TRANSPARENT;
130 
131  rect.left -= REGION_WND_BORDER; rect.top -= REGION_WND_BORDER;
132  rect.right += REGION_WND_BORDER; rect.bottom += REGION_WND_BORDER;
133 
134  AdjustWindowRectEx(&rect, style, FALSE, ex);
135 
136  // Create a window with no owner; use WC_DIALOG instead of writing a custom
137  // window class
138  hwnd = CreateWindowEx(ex, WC_DIALOG, NULL, style, rect.left, rect.top,
139  rect.right - rect.left, rect.bottom - rect.top,
140  NULL, NULL, NULL, NULL);
141  if (!hwnd) {
142  WIN32_API_ERROR("Could not create region display window");
143  goto error;
144  }
145 
146  // Set the window shape to only include the border area
147  GetClientRect(hwnd, &rect);
148  region = CreateRectRgn(0, 0,
149  rect.right - rect.left, rect.bottom - rect.top);
150  region_interior = CreateRectRgn(REGION_WND_BORDER, REGION_WND_BORDER,
151  rect.right - rect.left - REGION_WND_BORDER,
152  rect.bottom - rect.top - REGION_WND_BORDER);
153  CombineRgn(region, region, region_interior, RGN_DIFF);
154  if (!SetWindowRgn(hwnd, region, FALSE)) {
155  WIN32_API_ERROR("Could not set window region");
156  goto error;
157  }
158  // The "region" memory is now owned by the window
159  region = NULL;
160  DeleteObject(region_interior);
161 
162  SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR) gdigrab_region_wnd_proc);
163 
164  ShowWindow(hwnd, SW_SHOW);
165 
166  gdigrab->region_hwnd = hwnd;
167 
168  return 0;
169 
170 error:
171  if (region)
172  DeleteObject(region);
173  if (region_interior)
174  DeleteObject(region_interior);
175  if (hwnd)
176  DestroyWindow(hwnd);
177  return 1;
178 }
179 
180 /**
181  * Cleanup/free the region outline window.
182  *
183  * @param s1 The format context.
184  * @param gdigrab gdigrab context.
185  */
186 static void
188 {
189  if (gdigrab->region_hwnd)
190  DestroyWindow(gdigrab->region_hwnd);
191  gdigrab->region_hwnd = NULL;
192 }
193 
194 /**
195  * Process the Windows message queue.
196  *
197  * This is important to prevent Windows from thinking the window has become
198  * unresponsive. As well, things like WM_PAINT (to actually draw the window
199  * contents) are handled from the message queue context.
200  *
201  * @param s1 The format context.
202  * @param gdigrab gdigrab context.
203  */
204 static void
206 {
207  HWND hwnd = gdigrab->region_hwnd;
208  MSG msg;
209 
210  while (PeekMessage(&msg, hwnd, 0, 0, PM_REMOVE)) {
211  DispatchMessage(&msg);
212  }
213 }
214 
215 /**
216  * Initializes the gdi grab device demuxer (public device demuxer API).
217  *
218  * @param s1 Context from avformat core
219  * @return AVERROR_IO error, 0 success
220  */
221 static int
223 {
224  struct gdigrab *gdigrab = s1->priv_data;
225 
226  HWND hwnd;
227  HDC source_hdc = NULL;
228  HDC dest_hdc = NULL;
229  BITMAPINFO bmi;
230  HBITMAP hbmp = NULL;
231  void *buffer = NULL;
232 
233  const char *filename = s1->url;
234  const char *name = NULL;
235  AVStream *st = NULL;
236 
237  int bpp;
238  int horzres;
239  int vertres;
240  int desktophorzres;
241  int desktopvertres;
242  RECT virtual_rect;
243  RECT clip_rect;
244  BITMAP bmp;
245  int ret;
246 
247  if (!strncmp(filename, "title=", 6)) {
248  name = filename + 6;
249  hwnd = FindWindow(NULL, name);
250  if (!hwnd) {
251  av_log(s1, AV_LOG_ERROR,
252  "Can't find window '%s', aborting.\n", name);
253  ret = AVERROR(EIO);
254  goto error;
255  }
256  if (gdigrab->show_region) {
258  "Can't show region when grabbing a window.\n");
259  gdigrab->show_region = 0;
260  }
261  } else if (!strcmp(filename, "desktop")) {
262  hwnd = NULL;
263  } else {
264  av_log(s1, AV_LOG_ERROR,
265  "Please use \"desktop\" or \"title=<windowname>\" to specify your target.\n");
266  ret = AVERROR(EIO);
267  goto error;
268  }
269 
270  /* This will get the device context for the selected window, or if
271  * none, the primary screen */
272  source_hdc = GetDC(hwnd);
273  if (!source_hdc) {
274  WIN32_API_ERROR("Couldn't get window device context");
275  ret = AVERROR(EIO);
276  goto error;
277  }
278  bpp = GetDeviceCaps(source_hdc, BITSPIXEL);
279 
280  if (hwnd) {
281  GetClientRect(hwnd, &virtual_rect);
282  } else {
283  /* desktop -- get the right height and width for scaling DPI */
284  horzres = GetDeviceCaps(source_hdc, HORZRES);
285  vertres = GetDeviceCaps(source_hdc, VERTRES);
286  desktophorzres = GetDeviceCaps(source_hdc, DESKTOPHORZRES);
287  desktopvertres = GetDeviceCaps(source_hdc, DESKTOPVERTRES);
288  virtual_rect.left = GetSystemMetrics(SM_XVIRTUALSCREEN);
289  virtual_rect.top = GetSystemMetrics(SM_YVIRTUALSCREEN);
290  virtual_rect.right = (virtual_rect.left + GetSystemMetrics(SM_CXVIRTUALSCREEN)) * desktophorzres / horzres;
291  virtual_rect.bottom = (virtual_rect.top + GetSystemMetrics(SM_CYVIRTUALSCREEN)) * desktopvertres / vertres;
292  }
293 
294  /* If no width or height set, use full screen/window area */
295  if (!gdigrab->width || !gdigrab->height) {
296  clip_rect.left = virtual_rect.left;
297  clip_rect.top = virtual_rect.top;
298  clip_rect.right = virtual_rect.right;
299  clip_rect.bottom = virtual_rect.bottom;
300  } else {
301  clip_rect.left = gdigrab->offset_x;
302  clip_rect.top = gdigrab->offset_y;
303  clip_rect.right = gdigrab->width + gdigrab->offset_x;
304  clip_rect.bottom = gdigrab->height + gdigrab->offset_y;
305  }
306 
307  if (clip_rect.left < virtual_rect.left ||
308  clip_rect.top < virtual_rect.top ||
309  clip_rect.right > virtual_rect.right ||
310  clip_rect.bottom > virtual_rect.bottom) {
311  av_log(s1, AV_LOG_ERROR,
312  "Capture area (%li,%li),(%li,%li) extends outside window area (%li,%li),(%li,%li)",
313  clip_rect.left, clip_rect.top,
314  clip_rect.right, clip_rect.bottom,
315  virtual_rect.left, virtual_rect.top,
316  virtual_rect.right, virtual_rect.bottom);
317  ret = AVERROR(EIO);
318  goto error;
319  }
320 
321 
322  if (name) {
323  av_log(s1, AV_LOG_INFO,
324  "Found window %s, capturing %lix%lix%i at (%li,%li)\n",
325  name,
326  clip_rect.right - clip_rect.left,
327  clip_rect.bottom - clip_rect.top,
328  bpp, clip_rect.left, clip_rect.top);
329  } else {
330  av_log(s1, AV_LOG_INFO,
331  "Capturing whole desktop as %lix%lix%i at (%li,%li)\n",
332  clip_rect.right - clip_rect.left,
333  clip_rect.bottom - clip_rect.top,
334  bpp, clip_rect.left, clip_rect.top);
335  }
336 
337  if (clip_rect.right - clip_rect.left <= 0 ||
338  clip_rect.bottom - clip_rect.top <= 0 || bpp%8) {
339  av_log(s1, AV_LOG_ERROR, "Invalid properties, aborting\n");
340  ret = AVERROR(EIO);
341  goto error;
342  }
343 
344  dest_hdc = CreateCompatibleDC(source_hdc);
345  if (!dest_hdc) {
346  WIN32_API_ERROR("Screen DC CreateCompatibleDC");
347  ret = AVERROR(EIO);
348  goto error;
349  }
350 
351  /* Create a DIB and select it into the dest_hdc */
352  bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
353  bmi.bmiHeader.biWidth = clip_rect.right - clip_rect.left;
354  bmi.bmiHeader.biHeight = -(clip_rect.bottom - clip_rect.top);
355  bmi.bmiHeader.biPlanes = 1;
356  bmi.bmiHeader.biBitCount = bpp;
357  bmi.bmiHeader.biCompression = BI_RGB;
358  bmi.bmiHeader.biSizeImage = 0;
359  bmi.bmiHeader.biXPelsPerMeter = 0;
360  bmi.bmiHeader.biYPelsPerMeter = 0;
361  bmi.bmiHeader.biClrUsed = 0;
362  bmi.bmiHeader.biClrImportant = 0;
363  hbmp = CreateDIBSection(dest_hdc, &bmi, DIB_RGB_COLORS,
364  &buffer, NULL, 0);
365  if (!hbmp) {
366  WIN32_API_ERROR("Creating DIB Section");
367  ret = AVERROR(EIO);
368  goto error;
369  }
370 
371  if (!SelectObject(dest_hdc, hbmp)) {
372  WIN32_API_ERROR("SelectObject");
373  ret = AVERROR(EIO);
374  goto error;
375  }
376 
377  /* Get info from the bitmap */
378  GetObject(hbmp, sizeof(BITMAP), &bmp);
379 
380  st = avformat_new_stream(s1, NULL);
381  if (!st) {
382  ret = AVERROR(ENOMEM);
383  goto error;
384  }
385  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
386 
387  gdigrab->frame_size = bmp.bmWidthBytes * bmp.bmHeight * bmp.bmPlanes;
388  gdigrab->header_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
389  (bpp <= 8 ? (1 << bpp) : 0) * sizeof(RGBQUAD) /* palette size */;
390  gdigrab->time_base = av_inv_q(gdigrab->framerate);
391  gdigrab->time_frame = av_gettime() / av_q2d(gdigrab->time_base);
392 
393  gdigrab->hwnd = hwnd;
394  gdigrab->source_hdc = source_hdc;
395  gdigrab->dest_hdc = dest_hdc;
396  gdigrab->hbmp = hbmp;
397  gdigrab->bmi = bmi;
398  gdigrab->buffer = buffer;
399  gdigrab->clip_rect = clip_rect;
400 
401  gdigrab->cursor_error_printed = 0;
402 
403  if (gdigrab->show_region) {
404  if (gdigrab_region_wnd_init(s1, gdigrab)) {
405  ret = AVERROR(EIO);
406  goto error;
407  }
408  }
409 
410  st->avg_frame_rate = av_inv_q(gdigrab->time_base);
411 
414  st->codecpar->bit_rate = (gdigrab->header_size + gdigrab->frame_size) * 1/av_q2d(gdigrab->time_base) * 8;
415 
416  return 0;
417 
418 error:
419  if (source_hdc)
420  ReleaseDC(hwnd, source_hdc);
421  if (dest_hdc)
422  DeleteDC(dest_hdc);
423  if (hbmp)
424  DeleteObject(hbmp);
425  if (source_hdc)
426  DeleteDC(source_hdc);
427  return ret;
428 }
429 
430 /**
431  * Paints a mouse pointer in a Win32 image.
432  *
433  * @param s1 Context of the log information
434  * @param s Current grad structure
435  */
437 {
438  CURSORINFO ci = {0};
439 
440 #define CURSOR_ERROR(str) \
441  if (!gdigrab->cursor_error_printed) { \
442  WIN32_API_ERROR(str); \
443  gdigrab->cursor_error_printed = 1; \
444  }
445 
446  ci.cbSize = sizeof(ci);
447 
448  if (GetCursorInfo(&ci)) {
449  HCURSOR icon = CopyCursor(ci.hCursor);
450  ICONINFO info;
451  POINT pos;
452  RECT clip_rect = gdigrab->clip_rect;
453  HWND hwnd = gdigrab->hwnd;
454  int horzres = GetDeviceCaps(gdigrab->source_hdc, HORZRES);
455  int vertres = GetDeviceCaps(gdigrab->source_hdc, VERTRES);
456  int desktophorzres = GetDeviceCaps(gdigrab->source_hdc, DESKTOPHORZRES);
457  int desktopvertres = GetDeviceCaps(gdigrab->source_hdc, DESKTOPVERTRES);
458  info.hbmMask = NULL;
459  info.hbmColor = NULL;
460 
461  if (ci.flags != CURSOR_SHOWING)
462  return;
463 
464  if (!icon) {
465  /* Use the standard arrow cursor as a fallback.
466  * You'll probably only hit this in Wine, which can't fetch
467  * the current system cursor. */
468  icon = CopyCursor(LoadCursor(NULL, IDC_ARROW));
469  }
470 
471  if (!GetIconInfo(icon, &info)) {
472  CURSOR_ERROR("Could not get icon info");
473  goto icon_error;
474  }
475 
476  pos.x = ci.ptScreenPos.x - clip_rect.left - info.xHotspot;
477  pos.y = ci.ptScreenPos.y - clip_rect.top - info.yHotspot;
478 
479  if (hwnd) {
480  RECT rect;
481 
482  if (GetWindowRect(hwnd, &rect)) {
483  pos.x -= rect.left;
484  pos.y -= rect.top;
485  } else {
486  CURSOR_ERROR("Couldn't get window rectangle");
487  goto icon_error;
488  }
489  }
490 
491  //that would keep the correct location of mouse with hidpi screens
492  pos.x = pos.x * desktophorzres / horzres;
493  pos.y = pos.y * desktopvertres / vertres;
494 
495  av_log(s1, AV_LOG_DEBUG, "Cursor pos (%li,%li) -> (%li,%li)\n",
496  ci.ptScreenPos.x, ci.ptScreenPos.y, pos.x, pos.y);
497 
498  if (pos.x >= 0 && pos.x <= clip_rect.right - clip_rect.left &&
499  pos.y >= 0 && pos.y <= clip_rect.bottom - clip_rect.top) {
500  if (!DrawIcon(gdigrab->dest_hdc, pos.x, pos.y, icon))
501  CURSOR_ERROR("Couldn't draw icon");
502  }
503 
504 icon_error:
505  if (info.hbmMask)
506  DeleteObject(info.hbmMask);
507  if (info.hbmColor)
508  DeleteObject(info.hbmColor);
509  if (icon)
510  DestroyCursor(icon);
511  } else {
512  CURSOR_ERROR("Couldn't get cursor info");
513  }
514 }
515 
516 /**
517  * Grabs a frame from gdi (public device demuxer API).
518  *
519  * @param s1 Context from avformat core
520  * @param pkt Packet holding the grabbed frame
521  * @return frame size in bytes
522  */
524 {
525  struct gdigrab *gdigrab = s1->priv_data;
526 
527  HDC dest_hdc = gdigrab->dest_hdc;
528  HDC source_hdc = gdigrab->source_hdc;
529  RECT clip_rect = gdigrab->clip_rect;
530  AVRational time_base = gdigrab->time_base;
531  int64_t time_frame = gdigrab->time_frame;
532 
533  BITMAPFILEHEADER bfh;
534  int file_size = gdigrab->header_size + gdigrab->frame_size;
535 
536  int64_t curtime, delay;
537 
538  /* Calculate the time of the next frame */
539  time_frame += INT64_C(1000000);
540 
541  /* Run Window message processing queue */
542  if (gdigrab->show_region)
543  gdigrab_region_wnd_update(s1, gdigrab);
544 
545  /* wait based on the frame rate */
546  for (;;) {
547  curtime = av_gettime();
548  delay = time_frame * av_q2d(time_base) - curtime;
549  if (delay <= 0) {
550  if (delay < INT64_C(-1000000) * av_q2d(time_base)) {
551  time_frame += INT64_C(1000000);
552  }
553  break;
554  }
555  if (s1->flags & AVFMT_FLAG_NONBLOCK) {
556  return AVERROR(EAGAIN);
557  } else {
558  av_usleep(delay);
559  }
560  }
561 
562  if (av_new_packet(pkt, file_size) < 0)
563  return AVERROR(ENOMEM);
564  pkt->pts = curtime;
565 
566  /* Blit screen grab */
567  if (!BitBlt(dest_hdc, 0, 0,
568  clip_rect.right - clip_rect.left,
569  clip_rect.bottom - clip_rect.top,
570  source_hdc,
571  clip_rect.left, clip_rect.top, SRCCOPY | CAPTUREBLT)) {
572  WIN32_API_ERROR("Failed to capture image");
573  return AVERROR(EIO);
574  }
575  if (gdigrab->draw_mouse)
576  paint_mouse_pointer(s1, gdigrab);
577 
578  /* Copy bits to packet data */
579 
580  bfh.bfType = 0x4d42; /* "BM" in little-endian */
581  bfh.bfSize = file_size;
582  bfh.bfReserved1 = 0;
583  bfh.bfReserved2 = 0;
584  bfh.bfOffBits = gdigrab->header_size;
585 
586  memcpy(pkt->data, &bfh, sizeof(bfh));
587 
588  memcpy(pkt->data + sizeof(bfh), &gdigrab->bmi.bmiHeader, sizeof(gdigrab->bmi.bmiHeader));
589 
590  if (gdigrab->bmi.bmiHeader.biBitCount <= 8)
591  GetDIBColorTable(dest_hdc, 0, 1 << gdigrab->bmi.bmiHeader.biBitCount,
592  (RGBQUAD *) (pkt->data + sizeof(bfh) + sizeof(gdigrab->bmi.bmiHeader)));
593 
594  memcpy(pkt->data + gdigrab->header_size, gdigrab->buffer, gdigrab->frame_size);
595 
596  gdigrab->time_frame = time_frame;
597 
598  return gdigrab->header_size + gdigrab->frame_size;
599 }
600 
601 /**
602  * Closes gdi frame grabber (public device demuxer API).
603  *
604  * @param s1 Context from avformat core
605  * @return 0 success, !0 failure
606  */
608 {
609  struct gdigrab *s = s1->priv_data;
610 
611  if (s->show_region)
613 
614  if (s->source_hdc)
615  ReleaseDC(s->hwnd, s->source_hdc);
616  if (s->dest_hdc)
617  DeleteDC(s->dest_hdc);
618  if (s->hbmp)
619  DeleteObject(s->hbmp);
620  if (s->source_hdc)
621  DeleteDC(s->source_hdc);
622 
623  return 0;
624 }
625 
626 #define OFFSET(x) offsetof(struct gdigrab, x)
627 #define DEC AV_OPT_FLAG_DECODING_PARAM
628 static const AVOption options[] = {
629  { "draw_mouse", "draw the mouse pointer", OFFSET(draw_mouse), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, DEC },
630  { "show_region", "draw border around capture area", OFFSET(show_region), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC },
631  { "framerate", "set video frame rate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "ntsc"}, 0, INT_MAX, DEC },
632  { "video_size", "set video frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
633  { "offset_x", "capture area x offset", OFFSET(offset_x), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC },
634  { "offset_y", "capture area y offset", OFFSET(offset_y), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC },
635  { NULL },
636 };
637 
638 static const AVClass gdigrab_class = {
639  .class_name = "GDIgrab indev",
640  .item_name = av_default_item_name,
641  .option = options,
642  .version = LIBAVUTIL_VERSION_INT,
643 };
644 
645 /** gdi grabber device demuxer declaration */
647  .name = "gdigrab",
648  .long_name = NULL_IF_CONFIG_SMALL("GDI API Windows frame grabber"),
649  .priv_data_size = sizeof(struct gdigrab),
650  .read_header = gdigrab_read_header,
651  .read_packet = gdigrab_read_packet,
652  .read_close = gdigrab_read_close,
653  .flags = AVFMT_NOFILE,
654  .priv_class = &gdigrab_class,
655 };
const char * name
Definition: avisynth_c.h:775
static int gdigrab_read_packet(AVFormatContext *s1, AVPacket *pkt)
Grabs a frame from gdi (public device demuxer API).
Definition: gdigrab.c:523
#define OFFSET(x)
Definition: gdigrab.c:626
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
int show_region
Draw border (private option)
Definition: gdigrab.c:49
AVOption.
Definition: opt.h:246
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
static const AVOption options[]
Definition: gdigrab.c:628
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:4811
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
int frame_size
Size in bytes of the frame pixel data.
Definition: gdigrab.c:43
BITMAPINFO bmi
Information describing DIB format.
Definition: gdigrab.c:59
int av_usleep(unsigned usec)
Sleep for a period of time.
Definition: time.c:84
HWND region_hwnd
Handle of the region border window.
Definition: gdigrab.c:64
static AVPacket pkt
static int gdigrab_read_close(AVFormatContext *s1)
Closes gdi frame grabber (public device demuxer API).
Definition: gdigrab.c:607
static void gdigrab_region_wnd_destroy(AVFormatContext *s1, struct gdigrab *gdigrab)
Cleanup/free the region outline window.
Definition: gdigrab.c:187
Format I/O context.
Definition: avformat.h:1342
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
#define AVFMT_FLAG_NONBLOCK
Do not block when reading packets from input.
Definition: avformat.h:1476
AVOptions.
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
RECT clip_rect
The subarea of the screen or window to clip.
Definition: gdigrab.c:62
static LRESULT CALLBACK gdigrab_region_wnd_proc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
Callback to handle Windows messages for the region outline window.
Definition: gdigrab.c:86
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1473
uint8_t * data
Definition: avcodec.h:1430
static double av_q2d(AVRational a)
Convert an AVRational to a double.
Definition: rational.h:104
AVInputFormat ff_gdigrab_demuxer
gdi grabber device demuxer declaration
Definition: gdigrab.c:646
HANDLE HWND
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3913
#define DEC
Definition: gdigrab.c:627
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
#define FALSE
Definition: windows2linux.h:37
static int gdigrab_read_header(AVFormatContext *s1)
Initializes the gdi grab device demuxer (public device demuxer API).
Definition: gdigrab.c:222
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
char * url
input or output URL.
Definition: avformat.h:1438
HBITMAP hbmp
Information on the bitmap captured.
Definition: gdigrab.c:60
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVRational framerate
Capture framerate (private option)
Definition: gdigrab.c:50
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:946
int64_t time_frame
Current time.
Definition: gdigrab.c:46
static void paint_mouse_pointer(AVFormatContext *s1, struct gdigrab *gdigrab)
Paints a mouse pointer in a Win32 image.
Definition: gdigrab.c:436
static const AVClass gdigrab_class
Definition: gdigrab.c:638
int height
Height of the grab frame (private option)
Definition: gdigrab.c:52
AVRational time_base
Time base.
Definition: gdigrab.c:45
int header_size
Size in bytes of the DIB header.
Definition: gdigrab.c:44
int32_t * LONG_PTR
HDC dest_hdc
Destination, source-compatible DC.
Definition: gdigrab.c:58
#define REGION_WND_BORDER
Definition: gdigrab.c:72
GDI Device Demuxer context.
Definition: gdigrab.c:40
void * buffer
The buffer containing the bitmap image data.
Definition: gdigrab.c:61
#define WIN32_API_ERROR(str)
Definition: gdigrab.c:69
static void error(const char *err)
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
Stream structure.
Definition: avformat.h:873
HWND hwnd
Handle of the window for the grab.
Definition: gdigrab.c:56
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
int cursor_error_printed
Definition: gdigrab.c:66
int offset_y
Capture y offset (private option)
Definition: gdigrab.c:54
int x
Definition: f_ebur128.c:91
Describe the class of an AVClass context structure.
Definition: log.h:67
Definition: f_ebur128.c:91
Rational number (pair of numerator and denominator).
Definition: rational.h:58
HDC source_hdc
Source device context.
Definition: gdigrab.c:57
offset must point to AVRational
Definition: opt.h:236
#define s1
Definition: regdef.h:38
offset must point to two consecutive integers
Definition: opt.h:233
uint32_t DWORD
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
int width
Width of the grab frame (private option)
Definition: gdigrab.c:51
int draw_mouse
Draw mouse cursor (private option)
Definition: gdigrab.c:48
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:465
void * HBITMAP
LONG_PTR LRESULT
static int gdigrab_region_wnd_init(AVFormatContext *s1, struct gdigrab *gdigrab)
Initialize the region outline window.
Definition: gdigrab.c:121
void * priv_data
Format private data.
Definition: avformat.h:1370
int offset_x
Capture x offset (private option)
Definition: gdigrab.c:53
#define CURSOR_ERROR(str)
unsigned int UINT
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
This structure stores compressed data.
Definition: avcodec.h:1407
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1423
static void gdigrab_region_wnd_update(AVFormatContext *s1, struct gdigrab *gdigrab)
Process the Windows message queue.
Definition: gdigrab.c:205
void * HDC