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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 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 "libavformat/internal.h"
23 #include "libavutil/log.h"
24 #include "libavutil/opt.h"
25 #include "libavutil/parseutils.h"
26 #include <windows.h>
27 #include <vfw.h>
28 #include "avdevice.h"
29 
30 /* Defines for VFW missing from MinGW.
31  * Remove this when MinGW incorporates them. */
32 #define HWND_MESSAGE ((HWND)-3)
33 
34 /* End of missing MinGW defines */
35 
36 struct vfw_ctx {
37  const AVClass *class;
38  HWND hwnd;
39  HANDLE mutex;
40  HANDLE event;
41  AVPacketList *pktl;
42  unsigned int curbufsize;
43  unsigned int frame_num;
44  char *video_size; /**< A string describing video size, set by a private option. */
45  char *framerate; /**< Set by a private option. */
46 };
47 
48 static enum AVPixelFormat vfw_pixfmt(DWORD biCompression, WORD biBitCount)
49 {
50  switch(biCompression) {
51  case MKTAG('U', 'Y', 'V', 'Y'):
52  return AV_PIX_FMT_UYVY422;
53  case MKTAG('Y', 'U', 'Y', '2'):
54  return AV_PIX_FMT_YUYV422;
55  case MKTAG('I', '4', '2', '0'):
56  return AV_PIX_FMT_YUV420P;
57  case BI_RGB:
58  switch(biBitCount) { /* 1-8 are untested */
59  case 1:
60  return AV_PIX_FMT_MONOWHITE;
61  case 4:
62  return AV_PIX_FMT_RGB4;
63  case 8:
64  return AV_PIX_FMT_RGB8;
65  case 16:
66  return AV_PIX_FMT_RGB555;
67  case 24:
68  return AV_PIX_FMT_BGR24;
69  case 32:
70  return AV_PIX_FMT_RGB32;
71  }
72  }
73  return AV_PIX_FMT_NONE;
74 }
75 
76 static enum AVCodecID vfw_codecid(DWORD biCompression)
77 {
78  switch(biCompression) {
79  case MKTAG('d', 'v', 's', 'd'):
80  return AV_CODEC_ID_DVVIDEO;
81  case MKTAG('M', 'J', 'P', 'G'):
82  case MKTAG('m', 'j', 'p', 'g'):
83  return AV_CODEC_ID_MJPEG;
84  }
85  return AV_CODEC_ID_NONE;
86 }
87 
88 #define dstruct(pctx, sname, var, type) \
89  av_log(pctx, AV_LOG_DEBUG, #var":\t%"type"\n", sname->var)
90 
91 static void dump_captureparms(AVFormatContext *s, CAPTUREPARMS *cparms)
92 {
93  av_log(s, AV_LOG_DEBUG, "CAPTUREPARMS\n");
94  dstruct(s, cparms, dwRequestMicroSecPerFrame, "lu");
95  dstruct(s, cparms, fMakeUserHitOKToCapture, "d");
96  dstruct(s, cparms, wPercentDropForError, "u");
97  dstruct(s, cparms, fYield, "d");
98  dstruct(s, cparms, dwIndexSize, "lu");
99  dstruct(s, cparms, wChunkGranularity, "u");
100  dstruct(s, cparms, fUsingDOSMemory, "d");
101  dstruct(s, cparms, wNumVideoRequested, "u");
102  dstruct(s, cparms, fCaptureAudio, "d");
103  dstruct(s, cparms, wNumAudioRequested, "u");
104  dstruct(s, cparms, vKeyAbort, "u");
105  dstruct(s, cparms, fAbortLeftMouse, "d");
106  dstruct(s, cparms, fAbortRightMouse, "d");
107  dstruct(s, cparms, fLimitEnabled, "d");
108  dstruct(s, cparms, wTimeLimit, "u");
109  dstruct(s, cparms, fMCIControl, "d");
110  dstruct(s, cparms, fStepMCIDevice, "d");
111  dstruct(s, cparms, dwMCIStartTime, "lu");
112  dstruct(s, cparms, dwMCIStopTime, "lu");
113  dstruct(s, cparms, fStepCaptureAt2x, "d");
114  dstruct(s, cparms, wStepCaptureAverageFrames, "u");
115  dstruct(s, cparms, dwAudioBufferSize, "lu");
116  dstruct(s, cparms, fDisableWriteCache, "d");
117  dstruct(s, cparms, AVStreamMaster, "u");
118 }
119 
120 static void dump_videohdr(AVFormatContext *s, VIDEOHDR *vhdr)
121 {
122 #ifdef DEBUG
123  av_log(s, AV_LOG_DEBUG, "VIDEOHDR\n");
124  dstruct(s, vhdr, lpData, "p");
125  dstruct(s, vhdr, dwBufferLength, "lu");
126  dstruct(s, vhdr, dwBytesUsed, "lu");
127  dstruct(s, vhdr, dwTimeCaptured, "lu");
128  dstruct(s, vhdr, dwUser, "lu");
129  dstruct(s, vhdr, dwFlags, "lu");
130  dstruct(s, vhdr, dwReserved[0], "lu");
131  dstruct(s, vhdr, dwReserved[1], "lu");
132  dstruct(s, vhdr, dwReserved[2], "lu");
133  dstruct(s, vhdr, dwReserved[3], "lu");
134 #endif
135 }
136 
137 static void dump_bih(AVFormatContext *s, BITMAPINFOHEADER *bih)
138 {
139  av_log(s, AV_LOG_DEBUG, "BITMAPINFOHEADER\n");
140  dstruct(s, bih, biSize, "lu");
141  dstruct(s, bih, biWidth, "ld");
142  dstruct(s, bih, biHeight, "ld");
143  dstruct(s, bih, biPlanes, "d");
144  dstruct(s, bih, biBitCount, "d");
145  dstruct(s, bih, biCompression, "lu");
146  av_log(s, AV_LOG_DEBUG, " biCompression:\t\"%.4s\"\n",
147  (char*) &bih->biCompression);
148  dstruct(s, bih, biSizeImage, "lu");
149  dstruct(s, bih, biXPelsPerMeter, "lu");
150  dstruct(s, bih, biYPelsPerMeter, "lu");
151  dstruct(s, bih, biClrUsed, "lu");
152  dstruct(s, bih, biClrImportant, "lu");
153 }
154 
155 static int shall_we_drop(AVFormatContext *s)
156 {
157  struct vfw_ctx *ctx = s->priv_data;
158  const uint8_t dropscore[] = {62, 75, 87, 100};
159  const int ndropscores = FF_ARRAY_ELEMS(dropscore);
160  unsigned int buffer_fullness = (ctx->curbufsize*100)/s->max_picture_buffer;
161 
162  if(dropscore[++ctx->frame_num%ndropscores] <= buffer_fullness) {
163  av_log(s, AV_LOG_ERROR,
164  "real-time buffer %d%% full! frame dropped!\n", buffer_fullness);
165  return 1;
166  }
167 
168  return 0;
169 }
170 
171 static LRESULT CALLBACK videostream_cb(HWND hwnd, LPVIDEOHDR vdhdr)
172 {
173  AVFormatContext *s;
174  struct vfw_ctx *ctx;
175  AVPacketList **ppktl, *pktl_next;
176 
177  s = (AVFormatContext *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
178  ctx = s->priv_data;
179 
180  dump_videohdr(s, vdhdr);
181 
182  if(shall_we_drop(s))
183  return FALSE;
184 
185  WaitForSingleObject(ctx->mutex, INFINITE);
186 
187  pktl_next = av_mallocz(sizeof(AVPacketList));
188  if(!pktl_next)
189  goto fail;
190 
191  if(av_new_packet(&pktl_next->pkt, vdhdr->dwBytesUsed) < 0) {
192  av_free(pktl_next);
193  goto fail;
194  }
195 
196  pktl_next->pkt.pts = vdhdr->dwTimeCaptured;
197  memcpy(pktl_next->pkt.data, vdhdr->lpData, vdhdr->dwBytesUsed);
198 
199  for(ppktl = &ctx->pktl ; *ppktl ; ppktl = &(*ppktl)->next);
200  *ppktl = pktl_next;
201 
202  ctx->curbufsize += vdhdr->dwBytesUsed;
203 
204  SetEvent(ctx->event);
205  ReleaseMutex(ctx->mutex);
206 
207  return TRUE;
208 fail:
209  ReleaseMutex(ctx->mutex);
210  return FALSE;
211 }
212 
213 static int vfw_read_close(AVFormatContext *s)
214 {
215  struct vfw_ctx *ctx = s->priv_data;
216  AVPacketList *pktl;
217 
218  if(ctx->hwnd) {
219  SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
220  SendMessage(ctx->hwnd, WM_CAP_DRIVER_DISCONNECT, 0, 0);
221  DestroyWindow(ctx->hwnd);
222  }
223  if(ctx->mutex)
224  CloseHandle(ctx->mutex);
225  if(ctx->event)
226  CloseHandle(ctx->event);
227 
228  pktl = ctx->pktl;
229  while (pktl) {
230  AVPacketList *next = pktl->next;
231  av_destruct_packet(&pktl->pkt);
232  av_free(pktl);
233  pktl = next;
234  }
235 
236  return 0;
237 }
238 
239 static int vfw_read_header(AVFormatContext *s)
240 {
241  struct vfw_ctx *ctx = s->priv_data;
242  AVCodecContext *codec;
243  AVStream *st;
244  int devnum;
245  int bisize;
246  BITMAPINFO *bi = NULL;
247  CAPTUREPARMS cparms;
248  DWORD biCompression;
249  WORD biBitCount;
250  int ret;
251  AVRational framerate_q;
252 
253  if (!strcmp(s->filename, "list")) {
254  for (devnum = 0; devnum <= 9; devnum++) {
255  char driver_name[256];
256  char driver_ver[256];
257  ret = capGetDriverDescription(devnum,
258  driver_name, sizeof(driver_name),
259  driver_ver, sizeof(driver_ver));
260  if (ret) {
261  av_log(s, AV_LOG_INFO, "Driver %d\n", devnum);
262  av_log(s, AV_LOG_INFO, " %s\n", driver_name);
263  av_log(s, AV_LOG_INFO, " %s\n", driver_ver);
264  }
265  }
266  return AVERROR(EIO);
267  }
268 
269  ctx->hwnd = capCreateCaptureWindow(NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
270  if(!ctx->hwnd) {
271  av_log(s, AV_LOG_ERROR, "Could not create capture window.\n");
272  return AVERROR(EIO);
273  }
274 
275  /* If atoi fails, devnum==0 and the default device is used */
276  devnum = atoi(s->filename);
277 
278  ret = SendMessage(ctx->hwnd, WM_CAP_DRIVER_CONNECT, devnum, 0);
279  if(!ret) {
280  av_log(s, AV_LOG_ERROR, "Could not connect to device.\n");
281  DestroyWindow(ctx->hwnd);
282  return AVERROR(ENODEV);
283  }
284 
285  SendMessage(ctx->hwnd, WM_CAP_SET_OVERLAY, 0, 0);
286  SendMessage(ctx->hwnd, WM_CAP_SET_PREVIEW, 0, 0);
287 
288  ret = SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0,
289  (LPARAM) videostream_cb);
290  if(!ret) {
291  av_log(s, AV_LOG_ERROR, "Could not set video stream callback.\n");
292  goto fail;
293  }
294 
295  SetWindowLongPtr(ctx->hwnd, GWLP_USERDATA, (LONG_PTR) s);
296 
297  st = avformat_new_stream(s, NULL);
298  if(!st) {
299  vfw_read_close(s);
300  return AVERROR(ENOMEM);
301  }
302 
303  /* Set video format */
304  bisize = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, 0, 0);
305  if(!bisize)
306  goto fail;
307  bi = av_malloc(bisize);
308  if(!bi) {
309  vfw_read_close(s);
310  return AVERROR(ENOMEM);
311  }
312  ret = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, bisize, (LPARAM) bi);
313  if(!ret)
314  goto fail;
315 
316  dump_bih(s, &bi->bmiHeader);
317 
318  ret = av_parse_video_rate(&framerate_q, ctx->framerate);
319  if (ret < 0) {
320  av_log(s, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", ctx->framerate);
321  goto fail;
322  }
323 
324  if (ctx->video_size) {
325  ret = av_parse_video_size(&bi->bmiHeader.biWidth, &bi->bmiHeader.biHeight, ctx->video_size);
326  if (ret < 0) {
327  av_log(s, AV_LOG_ERROR, "Couldn't parse video size.\n");
328  goto fail;
329  }
330  }
331 
332  if (0) {
333  /* For testing yet unsupported compressions
334  * Copy these values from user-supplied verbose information */
335  bi->bmiHeader.biWidth = 320;
336  bi->bmiHeader.biHeight = 240;
337  bi->bmiHeader.biPlanes = 1;
338  bi->bmiHeader.biBitCount = 12;
339  bi->bmiHeader.biCompression = MKTAG('I','4','2','0');
340  bi->bmiHeader.biSizeImage = 115200;
341  dump_bih(s, &bi->bmiHeader);
342  }
343 
344  ret = SendMessage(ctx->hwnd, WM_CAP_SET_VIDEOFORMAT, bisize, (LPARAM) bi);
345  if(!ret) {
346  av_log(s, AV_LOG_ERROR, "Could not set Video Format.\n");
347  goto fail;
348  }
349 
350  biCompression = bi->bmiHeader.biCompression;
351  biBitCount = bi->bmiHeader.biBitCount;
352 
353  /* Set sequence setup */
354  ret = SendMessage(ctx->hwnd, WM_CAP_GET_SEQUENCE_SETUP, sizeof(cparms),
355  (LPARAM) &cparms);
356  if(!ret)
357  goto fail;
358 
359  dump_captureparms(s, &cparms);
360 
361  cparms.fYield = 1; // Spawn a background thread
362  cparms.dwRequestMicroSecPerFrame =
363  (framerate_q.den*1000000) / framerate_q.num;
364  cparms.fAbortLeftMouse = 0;
365  cparms.fAbortRightMouse = 0;
366  cparms.fCaptureAudio = 0;
367  cparms.vKeyAbort = 0;
368 
369  ret = SendMessage(ctx->hwnd, WM_CAP_SET_SEQUENCE_SETUP, sizeof(cparms),
370  (LPARAM) &cparms);
371  if(!ret)
372  goto fail;
373 
374  codec = st->codec;
375  codec->time_base = av_inv_q(framerate_q);
376  codec->codec_type = AVMEDIA_TYPE_VIDEO;
377  codec->width = bi->bmiHeader.biWidth;
378  codec->height = bi->bmiHeader.biHeight;
379  codec->pix_fmt = vfw_pixfmt(biCompression, biBitCount);
380  if(codec->pix_fmt == AV_PIX_FMT_NONE) {
381  codec->codec_id = vfw_codecid(biCompression);
382  if(codec->codec_id == AV_CODEC_ID_NONE) {
383  av_log(s, AV_LOG_ERROR, "Unknown compression type. "
384  "Please report verbose (-v 9) debug information.\n");
385  vfw_read_close(s);
386  return AVERROR_PATCHWELCOME;
387  }
388  codec->bits_per_coded_sample = biBitCount;
389  } else {
390  codec->codec_id = AV_CODEC_ID_RAWVIDEO;
391  if(biCompression == BI_RGB) {
392  codec->bits_per_coded_sample = biBitCount;
393  codec->extradata = av_malloc(9 + FF_INPUT_BUFFER_PADDING_SIZE);
394  if (codec->extradata) {
395  codec->extradata_size = 9;
396  memcpy(codec->extradata, "BottomUp", 9);
397  }
398  }
399  }
400 
401  av_freep(&bi);
402 
403  avpriv_set_pts_info(st, 32, 1, 1000);
404 
405  ctx->mutex = CreateMutex(NULL, 0, NULL);
406  if(!ctx->mutex) {
407  av_log(s, AV_LOG_ERROR, "Could not create Mutex.\n" );
408  goto fail;
409  }
410  ctx->event = CreateEvent(NULL, 1, 0, NULL);
411  if(!ctx->event) {
412  av_log(s, AV_LOG_ERROR, "Could not create Event.\n" );
413  goto fail;
414  }
415 
416  ret = SendMessage(ctx->hwnd, WM_CAP_SEQUENCE_NOFILE, 0, 0);
417  if(!ret) {
418  av_log(s, AV_LOG_ERROR, "Could not start capture sequence.\n" );
419  goto fail;
420  }
421 
422  return 0;
423 
424 fail:
425  av_freep(&bi);
426  vfw_read_close(s);
427  return AVERROR(EIO);
428 }
429 
430 static int vfw_read_packet(AVFormatContext *s, AVPacket *pkt)
431 {
432  struct vfw_ctx *ctx = s->priv_data;
433  AVPacketList *pktl = NULL;
434 
435  while(!pktl) {
436  WaitForSingleObject(ctx->mutex, INFINITE);
437  pktl = ctx->pktl;
438  if(ctx->pktl) {
439  *pkt = ctx->pktl->pkt;
440  ctx->pktl = ctx->pktl->next;
441  av_free(pktl);
442  }
443  ResetEvent(ctx->event);
444  ReleaseMutex(ctx->mutex);
445  if(!pktl) {
446  if(s->flags & AVFMT_FLAG_NONBLOCK) {
447  return AVERROR(EAGAIN);
448  } else {
449  WaitForSingleObject(ctx->event, INFINITE);
450  }
451  }
452  }
453 
454  ctx->curbufsize -= pkt->size;
455 
456  return pkt->size;
457 }
458 
459 #define OFFSET(x) offsetof(struct vfw_ctx, x)
460 #define DEC AV_OPT_FLAG_DECODING_PARAM
461 static const AVOption options[] = {
462  { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
463  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
464  { NULL },
465 };
466 
467 static const AVClass vfw_class = {
468  .class_name = "VFW indev",
469  .item_name = av_default_item_name,
470  .option = options,
471  .version = LIBAVUTIL_VERSION_INT,
472 };
473 
474 AVInputFormat ff_vfwcap_demuxer = {
475  .name = "vfwcap",
476  .long_name = NULL_IF_CONFIG_SMALL("VfW video capture"),
477  .priv_data_size = sizeof(struct vfw_ctx),
478  .read_header = vfw_read_header,
479  .read_packet = vfw_read_packet,
480  .read_close = vfw_read_close,
481  .flags = AVFMT_NOFILE,
482  .priv_class = &vfw_class,
483 };
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