FFmpeg: libavdevice/gdigrab.c Source File

FFmpeg
gdigrab.c
Go to the documentation of this file.
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 
66   int cursor_error_printed;
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
121  gdigrab_region_wnd_init(AVFormatContext *s1, struct gdigrab *gdigrab)
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
187  gdigrab_region_wnd_destroy(AVFormatContext *s1, struct gdigrab *gdigrab)
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
205  gdigrab_region_wnd_update(AVFormatContext *s1, struct gdigrab *gdigrab)
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
222  gdigrab_read_header(AVFormatContext *s1)
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->filename;
234  const char *name = NULL;
235  AVStream *st = NULL;
236 
237  int bpp;
238  int vertres;
239  int desktopvertres;
240  RECT virtual_rect;
241  RECT clip_rect;
242  BITMAP bmp;
243  int ret;
244 
245  if (!strncmp(filename, "title=", 6)) {
246  name = filename + 6;
247  hwnd = FindWindow(NULL, name);
248  if (!hwnd) {
249  av_log(s1, AV_LOG_ERROR,
250  "Can't find window '%s', aborting.\n", name);
251  ret = AVERROR(EIO);
252  goto error;
253  }
254  if (gdigrab->show_region) {
255  av_log(s1, AV_LOG_WARNING,
256  "Can't show region when grabbing a window.\n");
257  gdigrab->show_region = 0;
258  }
259  } else if (!strcmp(filename, "desktop")) {
260  hwnd = NULL;
261  } else {
262  av_log(s1, AV_LOG_ERROR,
263  "Please use \"desktop\" or \"title=<windowname>\" to specify your target.\n");
264  ret = AVERROR(EIO);
265  goto error;
266  }
267 
268  /* This will get the device context for the selected window, or if
269  * none, the primary screen */
270  source_hdc = GetDC(hwnd);
271  if (!source_hdc) {
272  WIN32_API_ERROR("Couldn't get window device context");
273  ret = AVERROR(EIO);
274  goto error;
275  }
276  bpp = GetDeviceCaps(source_hdc, BITSPIXEL);
277 
278  if (hwnd) {
279  GetClientRect(hwnd, &virtual_rect);
280  } else {
281  /* desktop -- get the right height and width for scaling DPI */
282  vertres = GetDeviceCaps(source_hdc, VERTRES);
283  desktopvertres = GetDeviceCaps(source_hdc, DESKTOPVERTRES);
284  virtual_rect.left = GetSystemMetrics(SM_XVIRTUALSCREEN);
285  virtual_rect.top = GetSystemMetrics(SM_YVIRTUALSCREEN);
286  virtual_rect.right = (virtual_rect.left + GetSystemMetrics(SM_CXVIRTUALSCREEN)) * desktopvertres / vertres;
287  virtual_rect.bottom = (virtual_rect.top + GetSystemMetrics(SM_CYVIRTUALSCREEN)) * desktopvertres / vertres;
288  }
289 
290  /* If no width or height set, use full screen/window area */
291  if (!gdigrab->width || !gdigrab->height) {
292  clip_rect.left = virtual_rect.left;
293  clip_rect.top = virtual_rect.top;
294  clip_rect.right = virtual_rect.right;
295  clip_rect.bottom = virtual_rect.bottom;
296  } else {
297  clip_rect.left = gdigrab->offset_x;
298  clip_rect.top = gdigrab->offset_y;
299  clip_rect.right = gdigrab->width + gdigrab->offset_x;
300  clip_rect.bottom = gdigrab->height + gdigrab->offset_y;
301  }
302 
303  if (clip_rect.left < virtual_rect.left ||
304  clip_rect.top < virtual_rect.top ||
305  clip_rect.right > virtual_rect.right ||
306  clip_rect.bottom > virtual_rect.bottom) {
307  av_log(s1, AV_LOG_ERROR,
308  "Capture area (%li,%li),(%li,%li) extends outside window area (%li,%li),(%li,%li)",
309  clip_rect.left, clip_rect.top,
310  clip_rect.right, clip_rect.bottom,
311  virtual_rect.left, virtual_rect.top,
312  virtual_rect.right, virtual_rect.bottom);
313  ret = AVERROR(EIO);
314  goto error;
315  }
316 
317 
318  if (name) {
319  av_log(s1, AV_LOG_INFO,
320  "Found window %s, capturing %lix%lix%i at (%li,%li)\n",
321  name,
322  clip_rect.right - clip_rect.left,
323  clip_rect.bottom - clip_rect.top,
324  bpp, clip_rect.left, clip_rect.top);
325  } else {
326  av_log(s1, AV_LOG_INFO,
327  "Capturing whole desktop as %lix%lix%i at (%li,%li)\n",
328  clip_rect.right - clip_rect.left,
329  clip_rect.bottom - clip_rect.top,
330  bpp, clip_rect.left, clip_rect.top);
331  }
332 
333  if (clip_rect.right - clip_rect.left <= 0 ||
334  clip_rect.bottom - clip_rect.top <= 0 || bpp%8) {
335  av_log(s1, AV_LOG_ERROR, "Invalid properties, aborting\n");
336  ret = AVERROR(EIO);
337  goto error;
338  }
339 
340  dest_hdc = CreateCompatibleDC(source_hdc);
341  if (!dest_hdc) {
342  WIN32_API_ERROR("Screen DC CreateCompatibleDC");
343  ret = AVERROR(EIO);
344  goto error;
345  }
346 
347  /* Create a DIB and select it into the dest_hdc */
348  bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
349  bmi.bmiHeader.biWidth = clip_rect.right - clip_rect.left;
350  bmi.bmiHeader.biHeight = -(clip_rect.bottom - clip_rect.top);
351  bmi.bmiHeader.biPlanes = 1;
352  bmi.bmiHeader.biBitCount = bpp;
353  bmi.bmiHeader.biCompression = BI_RGB;
354  bmi.bmiHeader.biSizeImage = 0;
355  bmi.bmiHeader.biXPelsPerMeter = 0;
356  bmi.bmiHeader.biYPelsPerMeter = 0;
357  bmi.bmiHeader.biClrUsed = 0;
358  bmi.bmiHeader.biClrImportant = 0;
359  hbmp = CreateDIBSection(dest_hdc, &bmi, DIB_RGB_COLORS,
360  &buffer, NULL, 0);
361  if (!hbmp) {
362  WIN32_API_ERROR("Creating DIB Section");
363  ret = AVERROR(EIO);
364  goto error;
365  }
366 
367  if (!SelectObject(dest_hdc, hbmp)) {
368  WIN32_API_ERROR("SelectObject");
369  ret = AVERROR(EIO);
370  goto error;
371  }
372 
373  /* Get info from the bitmap */
374  GetObject(hbmp, sizeof(BITMAP), &bmp);
375 
376  st = avformat_new_stream(s1, NULL);
377  if (!st) {
378  ret = AVERROR(ENOMEM);
379  goto error;
380  }
381  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
382 
383  gdigrab->frame_size = bmp.bmWidthBytes * bmp.bmHeight * bmp.bmPlanes;
384  gdigrab->header_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
385  (bpp <= 8 ? (1 << bpp) : 0) * sizeof(RGBQUAD) /* palette size */;
386  gdigrab->time_base = av_inv_q(gdigrab->framerate);
387  gdigrab->time_frame = av_gettime() / av_q2d(gdigrab->time_base);
388 
389  gdigrab->hwnd = hwnd;
390  gdigrab->source_hdc = source_hdc;
391  gdigrab->dest_hdc = dest_hdc;
392  gdigrab->hbmp = hbmp;
393  gdigrab->bmi = bmi;
394  gdigrab->buffer = buffer;
395  gdigrab->clip_rect = clip_rect;
396 
397  gdigrab->cursor_error_printed = 0;
398 
399  if (gdigrab->show_region) {
400  if (gdigrab_region_wnd_init(s1, gdigrab)) {
401  ret = AVERROR(EIO);
402  goto error;
403  }
404  }
405 
406  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
407  st->codec->codec_id = AV_CODEC_ID_BMP;
408  st->codec->time_base = gdigrab->time_base;
409  st->codec->bit_rate = (gdigrab->header_size + gdigrab->frame_size) * 1/av_q2d(gdigrab->time_base) * 8;
410 
411  return 0;
412 
413 error:
414  if (source_hdc)
415  ReleaseDC(hwnd, source_hdc);
416  if (dest_hdc)
417  DeleteDC(dest_hdc);
418  if (hbmp)
419  DeleteObject(hbmp);
420  if (source_hdc)
421  DeleteDC(source_hdc);
422  return ret;
423 }
424 
425 /**
426  * Paints a mouse pointer in a Win32 image.
427  *
428  * @param s1 Context of the log information
429  * @param s Current grad structure
430  */
431  static void paint_mouse_pointer(AVFormatContext *s1, struct gdigrab *gdigrab)
432 {
433  CURSORINFO ci = {0};
434 
435 #define CURSOR_ERROR(str) \
436  if (!gdigrab->cursor_error_printed) { \
437  WIN32_API_ERROR(str); \
438  gdigrab->cursor_error_printed = 1; \
439  }
440 
441  ci.cbSize = sizeof(ci);
442 
443  if (GetCursorInfo(&ci)) {
444  HCURSOR icon = CopyCursor(ci.hCursor);
445  ICONINFO info;
446  POINT pos;
447  RECT clip_rect = gdigrab->clip_rect;
448  HWND hwnd = gdigrab->hwnd;
449  info.hbmMask = NULL;
450  info.hbmColor = NULL;
451 
452  if (ci.flags != CURSOR_SHOWING)
453  return;
454 
455  if (!icon) {
456  /* Use the standard arrow cursor as a fallback.
457  * You'll probably only hit this in Wine, which can't fetch
458  * the current system cursor. */
459  icon = CopyCursor(LoadCursor(NULL, IDC_ARROW));
460  }
461 
462  if (!GetIconInfo(icon, &info)) {
463  CURSOR_ERROR("Could not get icon info");
464  goto icon_error;
465  }
466 
467  pos.x = ci.ptScreenPos.x - clip_rect.left - info.xHotspot;
468  pos.y = ci.ptScreenPos.y - clip_rect.top - info.yHotspot;
469 
470  if (hwnd) {
471  RECT rect;
472 
473  if (GetWindowRect(hwnd, &rect)) {
474  pos.x -= rect.left;
475  pos.y -= rect.top;
476  } else {
477  CURSOR_ERROR("Couldn't get window rectangle");
478  goto icon_error;
479  }
480  }
481 
482  av_log(s1, AV_LOG_DEBUG, "Cursor pos (%li,%li) -> (%li,%li)\n",
483  ci.ptScreenPos.x, ci.ptScreenPos.y, pos.x, pos.y);
484 
485  if (pos.x >= 0 && pos.x <= clip_rect.right - clip_rect.left &&
486  pos.y >= 0 && pos.y <= clip_rect.bottom - clip_rect.top) {
487  if (!DrawIcon(gdigrab->dest_hdc, pos.x, pos.y, icon))
488  CURSOR_ERROR("Couldn't draw icon");
489  }
490 
491 icon_error:
492  if (info.hbmMask)
493  DeleteObject(info.hbmMask);
494  if (info.hbmColor)
495  DeleteObject(info.hbmColor);
496  if (icon)
497  DestroyCursor(icon);
498  } else {
499  CURSOR_ERROR("Couldn't get cursor info");
500  }
501 }
502 
503 /**
504  * Grabs a frame from gdi (public device demuxer API).
505  *
506  * @param s1 Context from avformat core
507  * @param pkt Packet holding the grabbed frame
508  * @return frame size in bytes
509  */
510  static int gdigrab_read_packet(AVFormatContext *s1, AVPacket *pkt)
511 {
512  struct gdigrab *gdigrab = s1->priv_data;
513 
514  HDC dest_hdc = gdigrab->dest_hdc;
515  HDC source_hdc = gdigrab->source_hdc;
516  RECT clip_rect = gdigrab->clip_rect;
517  AVRational time_base = gdigrab->time_base;
518  int64_t time_frame = gdigrab->time_frame;
519 
520  BITMAPFILEHEADER bfh;
521  int file_size = gdigrab->header_size + gdigrab->frame_size;
522 
523  int64_t curtime, delay;
524 
525  /* Calculate the time of the next frame */
526  time_frame += INT64_C(1000000);
527 
528  /* Run Window message processing queue */
529  if (gdigrab->show_region)
530  gdigrab_region_wnd_update(s1, gdigrab);
531 
532  /* wait based on the frame rate */
533  for (;;) {
534  curtime = av_gettime();
535  delay = time_frame * av_q2d(time_base) - curtime;
536  if (delay <= 0) {
537  if (delay < INT64_C(-1000000) * av_q2d(time_base)) {
538  time_frame += INT64_C(1000000);
539  }
540  break;
541  }
542  if (s1->flags & AVFMT_FLAG_NONBLOCK) {
543  return AVERROR(EAGAIN);
544  } else {
545  av_usleep(delay);
546  }
547  }
548 
549  if (av_new_packet(pkt, file_size) < 0)
550  return AVERROR(ENOMEM);
551  pkt->pts = curtime;
552 
553  /* Blit screen grab */
554  if (!BitBlt(dest_hdc, 0, 0,
555  clip_rect.right - clip_rect.left,
556  clip_rect.bottom - clip_rect.top,
557  source_hdc,
558  clip_rect.left, clip_rect.top, SRCCOPY | CAPTUREBLT)) {
559  WIN32_API_ERROR("Failed to capture image");
560  return AVERROR(EIO);
561  }
562  if (gdigrab->draw_mouse)
563  paint_mouse_pointer(s1, gdigrab);
564 
565  /* Copy bits to packet data */
566 
567  bfh.bfType = 0x4d42; /* "BM" in little-endian */
568  bfh.bfSize = file_size;
569  bfh.bfReserved1 = 0;
570  bfh.bfReserved2 = 0;
571  bfh.bfOffBits = gdigrab->header_size;
572 
573  memcpy(pkt->data, &bfh, sizeof(bfh));
574 
575  memcpy(pkt->data + sizeof(bfh), &gdigrab->bmi.bmiHeader, sizeof(gdigrab->bmi.bmiHeader));
576 
577  if (gdigrab->bmi.bmiHeader.biBitCount <= 8)
578  GetDIBColorTable(dest_hdc, 0, 1 << gdigrab->bmi.bmiHeader.biBitCount,
579  (RGBQUAD *) (pkt->data + sizeof(bfh) + sizeof(gdigrab->bmi.bmiHeader)));
580 
581  memcpy(pkt->data + gdigrab->header_size, gdigrab->buffer, gdigrab->frame_size);
582 
583  gdigrab->time_frame = time_frame;
584 
585  return gdigrab->header_size + gdigrab->frame_size;
586 }
587 
588 /**
589  * Closes gdi frame grabber (public device demuxer API).
590  *
591  * @param s1 Context from avformat core
592  * @return 0 success, !0 failure
593  */
594  static int gdigrab_read_close(AVFormatContext *s1)
595 {
596  struct gdigrab *s = s1->priv_data;
597 
598  if (s->show_region)
599  gdigrab_region_wnd_destroy(s1, s);
600 
601  if (s->source_hdc)
602  ReleaseDC(s->hwnd, s->source_hdc);
603  if (s->dest_hdc)
604  DeleteDC(s->dest_hdc);
605  if (s->hbmp)
606  DeleteObject(s->hbmp);
607  if (s->source_hdc)
608  DeleteDC(s->source_hdc);
609 
610  return 0;
611 }
612 
613  #define OFFSET(x) offsetof(struct gdigrab, x)
614  #define DEC AV_OPT_FLAG_DECODING_PARAM
615  static const AVOption options[] = {
616  { "draw_mouse", "draw the mouse pointer", OFFSET(draw_mouse), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, DEC },
617  { "show_region", "draw border around capture area", OFFSET(show_region), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC },
618  { "framerate", "set video frame rate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "ntsc"}, 0, 0, DEC },
619  { "video_size", "set video frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
620  { "offset_x", "capture area x offset", OFFSET(offset_x), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC },
621  { "offset_y", "capture area y offset", OFFSET(offset_y), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC },
622  { NULL },
623 };
624 
625  static const AVClass gdigrab_class = {
626  .class_name = "GDIgrab indev",
627  .item_name = av_default_item_name,
628  .option = options,
629  .version = LIBAVUTIL_VERSION_INT,
630 };
631 
632 /** gdi grabber device demuxer declaration */
633  AVInputFormat ff_gdigrab_demuxer = {
634  .name = "gdigrab",
635  .long_name = NULL_IF_CONFIG_SMALL("GDI API Windows frame grabber"),
636  .priv_data_size = sizeof(struct gdigrab),
637  .read_header = gdigrab_read_header,
638  .read_packet = gdigrab_read_packet,
639  .read_close = gdigrab_read_close,
640  .flags = AVFMT_NOFILE,
641  .priv_class = &gdigrab_class,
642 };
gdigrab_read_packet
static int gdigrab_read_packet(AVFormatContext *s1, AVPacket *pkt)
Grabs a frame from gdi (public device demuxer API).
Definition: gdigrab.c:510
OFFSET
#define OFFSET(x)
Definition: gdigrab.c:613
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:631
gdigrab::show_region
int show_region
Draw border (private option)
Definition: gdigrab.c:49
AVOption
AVOption.
Definition: opt.h:245
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1597
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:70
options
static const AVOption options[]
Definition: gdigrab.c:615
avpriv_set_pts_info
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:4149
AV_OPT_TYPE_INT
Definition: opt.h:223
gdigrab::frame_size
int frame_size
Size in bytes of the frame pixel data.
Definition: gdigrab.c:43
gdigrab::bmi
BITMAPINFO bmi
Information describing DIB format.
Definition: gdigrab.c:59
av_usleep
int av_usleep(unsigned usec)
Sleep for a period of time.
Definition: time.c:76
gdigrab::region_hwnd
HWND region_hwnd
Handle of the region border window.
Definition: gdigrab.c:64
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
gdigrab_read_close
static int gdigrab_read_close(AVFormatContext *s1)
Closes gdi frame grabber (public device demuxer API).
Definition: gdigrab.c:594
AVCodecContext::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1661
gdigrab_region_wnd_destroy
static void gdigrab_region_wnd_destroy(AVFormatContext *s1, struct gdigrab *gdigrab)
Cleanup/free the region outline window.
Definition: gdigrab.c:187
AVFormatContext
Format I/O context.
Definition: avformat.h:1314
AVClass::class_name
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
AVFMT_FLAG_NONBLOCK
#define AVFMT_FLAG_NONBLOCK
Do not block when reading packets from input.
Definition: avformat.h:1428
opt.h
AVOptions.
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3805
gdigrab::clip_rect
RECT clip_rect
The subarea of the screen or window to clip.
Definition: gdigrab.c:62
gdigrab_region_wnd_proc
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
av_q2d
static double av_q2d(AVRational a)
Convert rational to double.
Definition: rational.h:80
AVFormatContext::flags
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1425
AVPacket::data
uint8_t * data
Definition: avcodec.h:1467
ff_gdigrab_demuxer
AVInputFormat ff_gdigrab_demuxer
gdi grabber device demuxer declaration
Definition: gdigrab.c:633
HWND
HANDLE HWND
Definition: basicDataTypeConversions.h:22
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
DEC
#define DEC
Definition: gdigrab.c:614
av_new_packet
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
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_default_item_name
av_default_item_name
Definition: libopenh264enc.c:68
AVERROR
#define AVERROR(e)
Definition: error.h:43
FALSE
#define FALSE
Definition: windows2linux.h:37
gdigrab_read_header
static int gdigrab_read_header(AVFormatContext *s1)
Initializes the gdi grab device demuxer (public device demuxer API).
Definition: gdigrab.c:222
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
gdigrab::hbmp
HBITMAP hbmp
Information on the bitmap captured.
Definition: gdigrab.c:60
AV_CODEC_ID_BMP
Definition: avcodec.h:185
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
gdigrab::framerate
AVRational framerate
Capture framerate (private option)
Definition: gdigrab.c:50
gdigrab::time_frame
int64_t time_frame
Current time.
Definition: gdigrab.c:46
paint_mouse_pointer
static void paint_mouse_pointer(AVFormatContext *s1, struct gdigrab *gdigrab)
Paints a mouse pointer in a Win32 image.
Definition: gdigrab.c:431
gdigrab_class
static const AVClass gdigrab_class
Definition: gdigrab.c:625
gdigrab::height
int height
Height of the grab frame (private option)
Definition: gdigrab.c:52
AVStream::codec
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
gdigrab::time_base
AVRational time_base
Time base.
Definition: gdigrab.c:45
gdigrab::header_size
int header_size
Size in bytes of the DIB header.
Definition: gdigrab.c:44
AVFormatContext::filename
char filename[1024]
input or output filename
Definition: avformat.h:1390
LONG_PTR
int32_t * LONG_PTR
Definition: basicDataTypeConversions.h:58
gdigrab::dest_hdc
HDC dest_hdc
Destination, source-compatible DC.
Definition: gdigrab.c:58
REGION_WND_BORDER
#define REGION_WND_BORDER
Definition: gdigrab.c:72
gdigrab
GDI Device Demuxer context.
Definition: gdigrab.c:40
gdigrab::buffer
void * buffer
The buffer containing the bitmap image data.
Definition: gdigrab.c:61
WIN32_API_ERROR
#define WIN32_API_ERROR(str)
Definition: gdigrab.c:69
av_gettime
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
AVStream
Stream structure.
Definition: avformat.h:877
gdigrab::hwnd
HWND hwnd
Handle of the window for the grab.
Definition: gdigrab.c:56
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:1540
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:1549
gdigrab::cursor_error_printed
int cursor_error_printed
Definition: gdigrab.c:66
gdigrab::offset_y
int offset_y
Capture y offset (private option)
Definition: gdigrab.c:54
rect::x
int x
Definition: f_ebur128.c:90
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
rect
Definition: f_ebur128.c:90
AVRational
rational number numerator/denominator
Definition: rational.h:43
gdigrab::source_hdc
HDC source_hdc
Source device context.
Definition: gdigrab.c:57
AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:235
s1
#define s1
Definition: regdef.h:38
AV_OPT_TYPE_IMAGE_SIZE
offset must point to two consecutive integers
Definition: opt.h:232
DWORD
uint32_t DWORD
Definition: basicDataTypeConversions.h:51
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:133
gdigrab::width
int width
Width of the grab frame (private option)
Definition: gdigrab.c:51
gdigrab::draw_mouse
int draw_mouse
Draw mouse cursor (private option)
Definition: gdigrab.c:48
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:477
HBITMAP
void * HBITMAP
Definition: basicDataTypeConversions.h:25
LRESULT
LONG_PTR LRESULT
Definition: basicDataTypeConversions.h:59
gdigrab_region_wnd_init
static int gdigrab_region_wnd_init(AVFormatContext *s1, struct gdigrab *gdigrab)
Initialize the region outline window.
Definition: gdigrab.c:121
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1342
gdigrab::offset_x
int offset_x
Capture x offset (private option)
Definition: gdigrab.c:53
CURSOR_ERROR
#define CURSOR_ERROR(str)
UINT
unsigned int UINT
Definition: basicDataTypeConversions.h:49
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:193
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1444
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1460
buffer
GLuint buffer
Definition: opengl_enc.c:102
name
const char * name
Definition: opengl_enc.c:103
gdigrab_region_wnd_update
static void gdigrab_region_wnd_update(AVFormatContext *s1, struct gdigrab *gdigrab)
Process the Windows message queue.
Definition: gdigrab.c:205
width
static int width
Definition: demuxing_decoding.c:39
HDC
void * HDC
Definition: basicDataTypeConversions.h:24
Generated on Mon Feb 15 2016 15:20:43 for FFmpeg by   doxygen 1.8.6

AltStyle によって変換されたページ (->オリジナル) /