vfwcap.c
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1 /*
2  * VFW capture interface
3  * Copyright (c) 2006-2008 Ramiro Polla
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavformat/avformat.h"
23 #include "libavformat/internal.h"
24 #include "libavutil/log.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/parseutils.h"
27 #include <windows.h>
28 #include <vfw.h>
29 
30 /* Defines for VFW missing from MinGW.
31  * Remove this when MinGW incorporates them. */
32 #define HWND_MESSAGE ((HWND)-3)
33 
34 #define BI_RGB 0
35 
36 /* End of missing MinGW defines */
37 
38 struct vfw_ctx {
39  const AVClass *class;
40  HWND hwnd;
41  HANDLE mutex;
42  HANDLE event;
44  unsigned int curbufsize;
45  unsigned int frame_num;
46  char *video_size;
47  char *framerate;
48 };
49 
50 static enum PixelFormat vfw_pixfmt(DWORD biCompression, WORD biBitCount)
51 {
52  switch(biCompression) {
53  case MKTAG('U', 'Y', 'V', 'Y'):
54  return PIX_FMT_UYVY422;
55  case MKTAG('Y', 'U', 'Y', '2'):
56  return PIX_FMT_YUYV422;
57  case MKTAG('I', '4', '2', '0'):
58  return PIX_FMT_YUV420P;
59  case BI_RGB:
60  switch(biBitCount) { /* 1-8 are untested */
61  case 1:
62  return PIX_FMT_MONOWHITE;
63  case 4:
64  return PIX_FMT_RGB4;
65  case 8:
66  return PIX_FMT_RGB8;
67  case 16:
68  return PIX_FMT_RGB555;
69  case 24:
70  return PIX_FMT_BGR24;
71  case 32:
72  return PIX_FMT_RGB32;
73  }
74  }
75  return PIX_FMT_NONE;
76 }
77 
78 static enum CodecID vfw_codecid(DWORD biCompression)
79 {
80  switch(biCompression) {
81  case MKTAG('d', 'v', 's', 'd'):
82  return CODEC_ID_DVVIDEO;
83  case MKTAG('M', 'J', 'P', 'G'):
84  case MKTAG('m', 'j', 'p', 'g'):
85  return CODEC_ID_MJPEG;
86  }
87  return CODEC_ID_NONE;
88 }
89 
90 #define dstruct(pctx, sname, var, type) \
91  av_log(pctx, AV_LOG_DEBUG, #var":\t%"type"\n", sname->var)
92 
93 static void dump_captureparms(AVFormatContext *s, CAPTUREPARMS *cparms)
94 {
95  av_log(s, AV_LOG_DEBUG, "CAPTUREPARMS\n");
96  dstruct(s, cparms, dwRequestMicroSecPerFrame, "lu");
97  dstruct(s, cparms, fMakeUserHitOKToCapture, "d");
98  dstruct(s, cparms, wPercentDropForError, "u");
99  dstruct(s, cparms, fYield, "d");
100  dstruct(s, cparms, dwIndexSize, "lu");
101  dstruct(s, cparms, wChunkGranularity, "u");
102  dstruct(s, cparms, fUsingDOSMemory, "d");
103  dstruct(s, cparms, wNumVideoRequested, "u");
104  dstruct(s, cparms, fCaptureAudio, "d");
105  dstruct(s, cparms, wNumAudioRequested, "u");
106  dstruct(s, cparms, vKeyAbort, "u");
107  dstruct(s, cparms, fAbortLeftMouse, "d");
108  dstruct(s, cparms, fAbortRightMouse, "d");
109  dstruct(s, cparms, fLimitEnabled, "d");
110  dstruct(s, cparms, wTimeLimit, "u");
111  dstruct(s, cparms, fMCIControl, "d");
112  dstruct(s, cparms, fStepMCIDevice, "d");
113  dstruct(s, cparms, dwMCIStartTime, "lu");
114  dstruct(s, cparms, dwMCIStopTime, "lu");
115  dstruct(s, cparms, fStepCaptureAt2x, "d");
116  dstruct(s, cparms, wStepCaptureAverageFrames, "u");
117  dstruct(s, cparms, dwAudioBufferSize, "lu");
118  dstruct(s, cparms, fDisableWriteCache, "d");
119  dstruct(s, cparms, AVStreamMaster, "u");
120 }
121 
122 static void dump_videohdr(AVFormatContext *s, VIDEOHDR *vhdr)
123 {
124 #ifdef DEBUG
125  av_log(s, AV_LOG_DEBUG, "VIDEOHDR\n");
126  dstruct(s, vhdr, lpData, "p");
127  dstruct(s, vhdr, dwBufferLength, "lu");
128  dstruct(s, vhdr, dwBytesUsed, "lu");
129  dstruct(s, vhdr, dwTimeCaptured, "lu");
130  dstruct(s, vhdr, dwUser, "lu");
131  dstruct(s, vhdr, dwFlags, "lu");
132  dstruct(s, vhdr, dwReserved[0], "lu");
133  dstruct(s, vhdr, dwReserved[1], "lu");
134  dstruct(s, vhdr, dwReserved[2], "lu");
135  dstruct(s, vhdr, dwReserved[3], "lu");
136 #endif
137 }
138 
139 static void dump_bih(AVFormatContext *s, BITMAPINFOHEADER *bih)
140 {
141  av_log(s, AV_LOG_DEBUG, "BITMAPINFOHEADER\n");
142  dstruct(s, bih, biSize, "lu");
143  dstruct(s, bih, biWidth, "ld");
144  dstruct(s, bih, biHeight, "ld");
145  dstruct(s, bih, biPlanes, "d");
146  dstruct(s, bih, biBitCount, "d");
147  dstruct(s, bih, biCompression, "lu");
148  av_log(s, AV_LOG_DEBUG, " biCompression:\t\"%.4s\"\n",
149  (char*) &bih->biCompression);
150  dstruct(s, bih, biSizeImage, "lu");
151  dstruct(s, bih, biXPelsPerMeter, "lu");
152  dstruct(s, bih, biYPelsPerMeter, "lu");
153  dstruct(s, bih, biClrUsed, "lu");
154  dstruct(s, bih, biClrImportant, "lu");
155 }
156 
158 {
159  struct vfw_ctx *ctx = s->priv_data;
160  const uint8_t dropscore[] = {62, 75, 87, 100};
161  const int ndropscores = FF_ARRAY_ELEMS(dropscore);
162  unsigned int buffer_fullness = (ctx->curbufsize*100)/s->max_picture_buffer;
163 
164  if(dropscore[++ctx->frame_num%ndropscores] <= buffer_fullness) {
165  av_log(s, AV_LOG_ERROR,
166  "real-time buffer %d%% full! frame dropped!\n", buffer_fullness);
167  return 1;
168  }
169 
170  return 0;
171 }
172 
173 static LRESULT CALLBACK videostream_cb(HWND hwnd, LPVIDEOHDR vdhdr)
174 {
175  AVFormatContext *s;
176  struct vfw_ctx *ctx;
177  AVPacketList **ppktl, *pktl_next;
178 
179  s = (AVFormatContext *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
180  ctx = s->priv_data;
181 
182  dump_videohdr(s, vdhdr);
183 
184  if(shall_we_drop(s))
185  return FALSE;
186 
187  WaitForSingleObject(ctx->mutex, INFINITE);
188 
189  pktl_next = av_mallocz(sizeof(AVPacketList));
190  if(!pktl_next)
191  goto fail;
192 
193  if(av_new_packet(&pktl_next->pkt, vdhdr->dwBytesUsed) < 0) {
194  av_free(pktl_next);
195  goto fail;
196  }
197 
198  pktl_next->pkt.pts = vdhdr->dwTimeCaptured;
199  memcpy(pktl_next->pkt.data, vdhdr->lpData, vdhdr->dwBytesUsed);
200 
201  for(ppktl = &ctx->pktl ; *ppktl ; ppktl = &(*ppktl)->next);
202  *ppktl = pktl_next;
203 
204  ctx->curbufsize += vdhdr->dwBytesUsed;
205 
206  SetEvent(ctx->event);
207  ReleaseMutex(ctx->mutex);
208 
209  return TRUE;
210 fail:
211  ReleaseMutex(ctx->mutex);
212  return FALSE;
213 }
214 
216 {
217  struct vfw_ctx *ctx = s->priv_data;
219 
220  if(ctx->hwnd) {
221  SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
222  SendMessage(ctx->hwnd, WM_CAP_DRIVER_DISCONNECT, 0, 0);
223  DestroyWindow(ctx->hwnd);
224  }
225  if(ctx->mutex)
226  CloseHandle(ctx->mutex);
227  if(ctx->event)
228  CloseHandle(ctx->event);
229 
230  pktl = ctx->pktl;
231  while (pktl) {
232  AVPacketList *next = pktl->next;
233  av_destruct_packet(&pktl->pkt);
234  av_free(pktl);
235  pktl = next;
236  }
237 
238  return 0;
239 }
240 
242 {
243  struct vfw_ctx *ctx = s->priv_data;
244  AVCodecContext *codec;
245  AVStream *st;
246  int devnum;
247  int bisize;
248  BITMAPINFO *bi;
249  CAPTUREPARMS cparms;
250  DWORD biCompression;
251  WORD biBitCount;
252  int ret;
253  AVRational framerate_q;
254 
255  if (!strcmp(s->filename, "list")) {
256  for (devnum = 0; devnum <= 9; devnum++) {
257  char driver_name[256];
258  char driver_ver[256];
259  ret = capGetDriverDescription(devnum,
260  driver_name, sizeof(driver_name),
261  driver_ver, sizeof(driver_ver));
262  if (ret) {
263  av_log(s, AV_LOG_INFO, "Driver %d\n", devnum);
264  av_log(s, AV_LOG_INFO, " %s\n", driver_name);
265  av_log(s, AV_LOG_INFO, " %s\n", driver_ver);
266  }
267  }
268  return AVERROR(EIO);
269  }
270 
271  ctx->hwnd = capCreateCaptureWindow(NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
272  if(!ctx->hwnd) {
273  av_log(s, AV_LOG_ERROR, "Could not create capture window.\n");
274  return AVERROR(EIO);
275  }
276 
277  /* If atoi fails, devnum==0 and the default device is used */
278  devnum = atoi(s->filename);
279 
280  ret = SendMessage(ctx->hwnd, WM_CAP_DRIVER_CONNECT, devnum, 0);
281  if(!ret) {
282  av_log(s, AV_LOG_ERROR, "Could not connect to device.\n");
283  DestroyWindow(ctx->hwnd);
284  return AVERROR(ENODEV);
285  }
286 
287  SendMessage(ctx->hwnd, WM_CAP_SET_OVERLAY, 0, 0);
288  SendMessage(ctx->hwnd, WM_CAP_SET_PREVIEW, 0, 0);
289 
290  ret = SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0,
291  (LPARAM) videostream_cb);
292  if(!ret) {
293  av_log(s, AV_LOG_ERROR, "Could not set video stream callback.\n");
294  goto fail_io;
295  }
296 
297  SetWindowLongPtr(ctx->hwnd, GWLP_USERDATA, (LONG_PTR) s);
298 
299  st = avformat_new_stream(s, NULL);
300  if(!st) {
301  vfw_read_close(s);
302  return AVERROR(ENOMEM);
303  }
304 
305  /* Set video format */
306  bisize = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, 0, 0);
307  if(!bisize)
308  goto fail_io;
309  bi = av_malloc(bisize);
310  if(!bi) {
311  vfw_read_close(s);
312  return AVERROR(ENOMEM);
313  }
314  ret = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, bisize, (LPARAM) bi);
315  if(!ret)
316  goto fail_bi;
317 
318  dump_bih(s, &bi->bmiHeader);
319 
320 
321  if (ctx->video_size) {
322  ret = av_parse_video_size(&bi->bmiHeader.biWidth, &bi->bmiHeader.biHeight, ctx->video_size);
323  if (ret < 0) {
324  av_log(s, AV_LOG_ERROR, "Couldn't parse video size.\n");
325  goto fail_bi;
326  }
327  }
328 
329  if (0) {
330  /* For testing yet unsupported compressions
331  * Copy these values from user-supplied verbose information */
332  bi->bmiHeader.biWidth = 320;
333  bi->bmiHeader.biHeight = 240;
334  bi->bmiHeader.biPlanes = 1;
335  bi->bmiHeader.biBitCount = 12;
336  bi->bmiHeader.biCompression = MKTAG('I','4','2','0');
337  bi->bmiHeader.biSizeImage = 115200;
338  dump_bih(s, &bi->bmiHeader);
339  }
340 
341  ret = SendMessage(ctx->hwnd, WM_CAP_SET_VIDEOFORMAT, bisize, (LPARAM) bi);
342  if(!ret) {
343  av_log(s, AV_LOG_ERROR, "Could not set Video Format.\n");
344  goto fail_bi;
345  }
346 
347  biCompression = bi->bmiHeader.biCompression;
348  biBitCount = bi->bmiHeader.biBitCount;
349 
350  av_free(bi);
351 
352  /* Set sequence setup */
353  ret = SendMessage(ctx->hwnd, WM_CAP_GET_SEQUENCE_SETUP, sizeof(cparms),
354  (LPARAM) &cparms);
355  if(!ret)
356  goto fail_io;
357 
358  dump_captureparms(s, &cparms);
359 
360  cparms.fYield = 1; // Spawn a background thread
361  cparms.dwRequestMicroSecPerFrame =
362  (framerate_q.den*1000000) / framerate_q.num;
363  cparms.fAbortLeftMouse = 0;
364  cparms.fAbortRightMouse = 0;
365  cparms.fCaptureAudio = 0;
366  cparms.vKeyAbort = 0;
367 
368  ret = SendMessage(ctx->hwnd, WM_CAP_SET_SEQUENCE_SETUP, sizeof(cparms),
369  (LPARAM) &cparms);
370  if(!ret)
371  goto fail_io;
372 
373  codec = st->codec;
374  codec->time_base = (AVRational){framerate_q.den, framerate_q.num};
376  codec->width = bi->bmiHeader.biWidth;
377  codec->height = bi->bmiHeader.biHeight;
378  codec->pix_fmt = vfw_pixfmt(biCompression, biBitCount);
379  if(codec->pix_fmt == PIX_FMT_NONE) {
380  codec->codec_id = vfw_codecid(biCompression);
381  if(codec->codec_id == CODEC_ID_NONE) {
382  av_log(s, AV_LOG_ERROR, "Unknown compression type. "
383  "Please report verbose (-v 9) debug information.\n");
384  vfw_read_close(s);
385  return AVERROR_PATCHWELCOME;
386  }
387  codec->bits_per_coded_sample = biBitCount;
388  } else {
389  codec->codec_id = CODEC_ID_RAWVIDEO;
390  if(biCompression == BI_RGB) {
391  codec->bits_per_coded_sample = biBitCount;
393  if (codec->extradata) {
394  codec->extradata_size = 9;
395  memcpy(codec->extradata, "BottomUp", 9);
396  }
397  }
398  }
399 
400  avpriv_set_pts_info(st, 32, 1, 1000);
401 
402  ctx->mutex = CreateMutex(NULL, 0, NULL);
403  if(!ctx->mutex) {
404  av_log(s, AV_LOG_ERROR, "Could not create Mutex.\n" );
405  goto fail_io;
406  }
407  ctx->event = CreateEvent(NULL, 1, 0, NULL);
408  if(!ctx->event) {
409  av_log(s, AV_LOG_ERROR, "Could not create Event.\n" );
410  goto fail_io;
411  }
412 
413  ret = SendMessage(ctx->hwnd, WM_CAP_SEQUENCE_NOFILE, 0, 0);
414  if(!ret) {
415  av_log(s, AV_LOG_ERROR, "Could not start capture sequence.\n" );
416  goto fail_io;
417  }
418 
419  return 0;
420 
421 fail_bi:
422  av_free(bi);
423 
424 fail_io:
425  vfw_read_close(s);
426  return AVERROR(EIO);
427 }
428 
430 {
431  struct vfw_ctx *ctx = s->priv_data;
433 
434  while(!pktl) {
435  WaitForSingleObject(ctx->mutex, INFINITE);
436  pktl = ctx->pktl;
437  if(ctx->pktl) {
438  *pkt = ctx->pktl->pkt;
439  ctx->pktl = ctx->pktl->next;
440  av_free(pktl);
441  }
442  ResetEvent(ctx->event);
443  ReleaseMutex(ctx->mutex);
444  if(!pktl) {
445  if(s->flags & AVFMT_FLAG_NONBLOCK) {
446  return AVERROR(EAGAIN);
447  } else {
448  WaitForSingleObject(ctx->event, INFINITE);
449  }
450  }
451  }
452 
453  ctx->curbufsize -= pkt->size;
454 
455  return pkt->size;
456 }
457 
458 #define OFFSET(x) offsetof(struct vfw_ctx, x)
459 #define DEC AV_OPT_FLAG_DECODING_PARAM
460 static const AVOption options[] = {
461  { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
462  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
463  { NULL },
464 };
465 
466 static const AVClass vfw_class = {
467  .class_name = "VFW indev",
468  .item_name = av_default_item_name,
469  .option = options,
470  .version = LIBAVUTIL_VERSION_INT,
471 };
472 
474  .name = "vfwcap",
475  .long_name = NULL_IF_CONFIG_SMALL("VfW video capture"),
476  .priv_data_size = sizeof(struct vfw_ctx),
477  .read_header = vfw_read_header,
478  .read_packet = vfw_read_packet,
479  .read_close = vfw_read_close,
480  .flags = AVFMT_NOFILE,
481  .priv_class = &vfw_class,
482 };