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libavdevice/vfwcap.c

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00001 /*
00002  * VFW capture interface
00003  * Copyright (c) 2006-2008 Ramiro Polla
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavformat/avformat.h"
00023 #include <windows.h>
00024 #include <vfw.h>
00025 
00026 //#define DEBUG_VFW
00027 
00028 /* Defines for VFW missing from MinGW.
00029  * Remove this when MinGW incorporates them. */
00030 #define HWND_MESSAGE                ((HWND)-3)
00031 
00032 #define BI_RGB                      0
00033 
00034 /* End of missing MinGW defines */
00035 
00036 struct vfw_ctx {
00037     HWND hwnd;
00038     HANDLE mutex;
00039     HANDLE event;
00040     AVPacketList *pktl;
00041     unsigned int curbufsize;
00042     unsigned int frame_num;
00043 };
00044 
00045 static enum PixelFormat vfw_pixfmt(DWORD biCompression, WORD biBitCount)
00046 {
00047     switch(biCompression) {
00048     case MKTAG('U', 'Y', 'V', 'Y'):
00049         return PIX_FMT_UYVY422;
00050     case MKTAG('Y', 'U', 'Y', '2'):
00051         return PIX_FMT_YUYV422;
00052     case MKTAG('I', '4', '2', '0'):
00053         return PIX_FMT_YUV420P;
00054     case BI_RGB:
00055         switch(biBitCount) { /* 1-8 are untested */
00056             case 1:
00057                 return PIX_FMT_MONOWHITE;
00058             case 4:
00059                 return PIX_FMT_RGB4;
00060             case 8:
00061                 return PIX_FMT_RGB8;
00062             case 16:
00063                 return PIX_FMT_RGB555;
00064             case 24:
00065                 return PIX_FMT_BGR24;
00066             case 32:
00067                 return PIX_FMT_RGB32;
00068         }
00069     }
00070     return PIX_FMT_NONE;
00071 }
00072 
00073 static enum CodecID vfw_codecid(DWORD biCompression)
00074 {
00075     switch(biCompression) {
00076     case MKTAG('d', 'v', 's', 'd'):
00077         return CODEC_ID_DVVIDEO;
00078     case MKTAG('M', 'J', 'P', 'G'):
00079     case MKTAG('m', 'j', 'p', 'g'):
00080         return CODEC_ID_MJPEG;
00081     }
00082     return CODEC_ID_NONE;
00083 }
00084 
00085 #define dstruct(pctx, sname, var, type) \
00086     av_log(pctx, AV_LOG_DEBUG, #var":\t%"type"\n", sname->var)
00087 
00088 static void dump_captureparms(AVFormatContext *s, CAPTUREPARMS *cparms)
00089 {
00090     av_log(s, AV_LOG_DEBUG, "CAPTUREPARMS\n");
00091     dstruct(s, cparms, dwRequestMicroSecPerFrame, "lu");
00092     dstruct(s, cparms, fMakeUserHitOKToCapture, "d");
00093     dstruct(s, cparms, wPercentDropForError, "u");
00094     dstruct(s, cparms, fYield, "d");
00095     dstruct(s, cparms, dwIndexSize, "lu");
00096     dstruct(s, cparms, wChunkGranularity, "u");
00097     dstruct(s, cparms, fUsingDOSMemory, "d");
00098     dstruct(s, cparms, wNumVideoRequested, "u");
00099     dstruct(s, cparms, fCaptureAudio, "d");
00100     dstruct(s, cparms, wNumAudioRequested, "u");
00101     dstruct(s, cparms, vKeyAbort, "u");
00102     dstruct(s, cparms, fAbortLeftMouse, "d");
00103     dstruct(s, cparms, fAbortRightMouse, "d");
00104     dstruct(s, cparms, fLimitEnabled, "d");
00105     dstruct(s, cparms, wTimeLimit, "u");
00106     dstruct(s, cparms, fMCIControl, "d");
00107     dstruct(s, cparms, fStepMCIDevice, "d");
00108     dstruct(s, cparms, dwMCIStartTime, "lu");
00109     dstruct(s, cparms, dwMCIStopTime, "lu");
00110     dstruct(s, cparms, fStepCaptureAt2x, "d");
00111     dstruct(s, cparms, wStepCaptureAverageFrames, "u");
00112     dstruct(s, cparms, dwAudioBufferSize, "lu");
00113     dstruct(s, cparms, fDisableWriteCache, "d");
00114     dstruct(s, cparms, AVStreamMaster, "u");
00115 }
00116 
00117 static void dump_videohdr(AVFormatContext *s, VIDEOHDR *vhdr)
00118 {
00119 #ifdef DEBUG_VFW
00120     av_log(s, AV_LOG_DEBUG, "VIDEOHDR\n");
00121     dstruct(s, vhdr, lpData, "p");
00122     dstruct(s, vhdr, dwBufferLength, "lu");
00123     dstruct(s, vhdr, dwBytesUsed, "lu");
00124     dstruct(s, vhdr, dwTimeCaptured, "lu");
00125     dstruct(s, vhdr, dwUser, "lu");
00126     dstruct(s, vhdr, dwFlags, "lu");
00127     dstruct(s, vhdr, dwReserved[0], "lu");
00128     dstruct(s, vhdr, dwReserved[1], "lu");
00129     dstruct(s, vhdr, dwReserved[2], "lu");
00130     dstruct(s, vhdr, dwReserved[3], "lu");
00131 #endif
00132 }
00133 
00134 static void dump_bih(AVFormatContext *s, BITMAPINFOHEADER *bih)
00135 {
00136     av_log(s, AV_LOG_DEBUG, "BITMAPINFOHEADER\n");
00137     dstruct(s, bih, biSize, "lu");
00138     dstruct(s, bih, biWidth, "ld");
00139     dstruct(s, bih, biHeight, "ld");
00140     dstruct(s, bih, biPlanes, "d");
00141     dstruct(s, bih, biBitCount, "d");
00142     dstruct(s, bih, biCompression, "lu");
00143     av_log(s, AV_LOG_DEBUG, "    biCompression:\t\"%.4s\"\n",
00144                    (char*) &bih->biCompression);
00145     dstruct(s, bih, biSizeImage, "lu");
00146     dstruct(s, bih, biXPelsPerMeter, "lu");
00147     dstruct(s, bih, biYPelsPerMeter, "lu");
00148     dstruct(s, bih, biClrUsed, "lu");
00149     dstruct(s, bih, biClrImportant, "lu");
00150 }
00151 
00152 static int shall_we_drop(AVFormatContext *s)
00153 {
00154     struct vfw_ctx *ctx = s->priv_data;
00155     const uint8_t dropscore[] = {62, 75, 87, 100};
00156     const int ndropscores = FF_ARRAY_ELEMS(dropscore);
00157     unsigned int buffer_fullness = (ctx->curbufsize*100)/s->max_picture_buffer;
00158 
00159     if(dropscore[++ctx->frame_num%ndropscores] <= buffer_fullness) {
00160         av_log(s, AV_LOG_ERROR,
00161               "real-time buffer %d%% full! frame dropped!\n", buffer_fullness);
00162         return 1;
00163     }
00164 
00165     return 0;
00166 }
00167 
00168 static LRESULT CALLBACK videostream_cb(HWND hwnd, LPVIDEOHDR vdhdr)
00169 {
00170     AVFormatContext *s;
00171     struct vfw_ctx *ctx;
00172     AVPacketList **ppktl, *pktl_next;
00173 
00174     s = (AVFormatContext *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
00175     ctx = s->priv_data;
00176 
00177     dump_videohdr(s, vdhdr);
00178 
00179     if(shall_we_drop(s))
00180         return FALSE;
00181 
00182     WaitForSingleObject(ctx->mutex, INFINITE);
00183 
00184     pktl_next = av_mallocz(sizeof(AVPacketList));
00185     if(!pktl_next)
00186         goto fail;
00187 
00188     if(av_new_packet(&pktl_next->pkt, vdhdr->dwBytesUsed) < 0) {
00189         av_free(pktl_next);
00190         goto fail;
00191     }
00192 
00193     pktl_next->pkt.pts = vdhdr->dwTimeCaptured;
00194     memcpy(pktl_next->pkt.data, vdhdr->lpData, vdhdr->dwBytesUsed);
00195 
00196     for(ppktl = &ctx->pktl ; *ppktl ; ppktl = &(*ppktl)->next);
00197     *ppktl = pktl_next;
00198 
00199     ctx->curbufsize += vdhdr->dwBytesUsed;
00200 
00201     SetEvent(ctx->event);
00202     ReleaseMutex(ctx->mutex);
00203 
00204     return TRUE;
00205 fail:
00206     ReleaseMutex(ctx->mutex);
00207     return FALSE;
00208 }
00209 
00210 static int vfw_read_close(AVFormatContext *s)
00211 {
00212     struct vfw_ctx *ctx = s->priv_data;
00213     AVPacketList *pktl;
00214 
00215     if(ctx->hwnd) {
00216         SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
00217         SendMessage(ctx->hwnd, WM_CAP_DRIVER_DISCONNECT, 0, 0);
00218         DestroyWindow(ctx->hwnd);
00219     }
00220     if(ctx->mutex)
00221         CloseHandle(ctx->mutex);
00222     if(ctx->event)
00223         CloseHandle(ctx->event);
00224 
00225     pktl = ctx->pktl;
00226     while (pktl) {
00227         AVPacketList *next = pktl->next;
00228         av_destruct_packet(&pktl->pkt);
00229         av_free(pktl);
00230         pktl = next;
00231     }
00232 
00233     return 0;
00234 }
00235 
00236 static int vfw_read_header(AVFormatContext *s, AVFormatParameters *ap)
00237 {
00238     struct vfw_ctx *ctx = s->priv_data;
00239     AVCodecContext *codec;
00240     AVStream *st;
00241     int devnum;
00242     int bisize;
00243     BITMAPINFO *bi;
00244     CAPTUREPARMS cparms;
00245     DWORD biCompression;
00246     WORD biBitCount;
00247     int width;
00248     int height;
00249     int ret;
00250 
00251     if(!ap->time_base.den) {
00252         av_log(s, AV_LOG_ERROR, "A time base must be specified.\n");
00253         return AVERROR(EIO);
00254     }
00255 
00256     ctx->hwnd = capCreateCaptureWindow(NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
00257     if(!ctx->hwnd) {
00258         av_log(s, AV_LOG_ERROR, "Could not create capture window.\n");
00259         return AVERROR(EIO);
00260     }
00261 
00262     /* If atoi fails, devnum==0 and the default device is used */
00263     devnum = atoi(s->filename);
00264 
00265     ret = SendMessage(ctx->hwnd, WM_CAP_DRIVER_CONNECT, devnum, 0);
00266     if(!ret) {
00267         av_log(s, AV_LOG_ERROR, "Could not connect to device.\n");
00268         DestroyWindow(ctx->hwnd);
00269         return AVERROR(ENODEV);
00270     }
00271 
00272     SendMessage(ctx->hwnd, WM_CAP_SET_OVERLAY, 0, 0);
00273     SendMessage(ctx->hwnd, WM_CAP_SET_PREVIEW, 0, 0);
00274 
00275     ret = SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0,
00276                       (LPARAM) videostream_cb);
00277     if(!ret) {
00278         av_log(s, AV_LOG_ERROR, "Could not set video stream callback.\n");
00279         goto fail_io;
00280     }
00281 
00282     SetWindowLongPtr(ctx->hwnd, GWLP_USERDATA, (LONG_PTR) s);
00283 
00284     st = av_new_stream(s, 0);
00285     if(!st) {
00286         vfw_read_close(s);
00287         return AVERROR(ENOMEM);
00288     }
00289 
00290     /* Set video format */
00291     bisize = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, 0, 0);
00292     if(!bisize)
00293         goto fail_io;
00294     bi = av_malloc(bisize);
00295     if(!bi) {
00296         vfw_read_close(s);
00297         return AVERROR(ENOMEM);
00298     }
00299     ret = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, bisize, (LPARAM) bi);
00300     if(!ret)
00301         goto fail_bi;
00302 
00303     dump_bih(s, &bi->bmiHeader);
00304 
00305     width  = ap->width  ? ap->width  : bi->bmiHeader.biWidth ;
00306     height = ap->height ? ap->height : bi->bmiHeader.biHeight;
00307     bi->bmiHeader.biWidth  = width ;
00308     bi->bmiHeader.biHeight = height;
00309 
00310     if (0) {
00311         /* For testing yet unsupported compressions
00312          * Copy these values from user-supplied verbose information */
00313         bi->bmiHeader.biWidth       = 320;
00314         bi->bmiHeader.biHeight      = 240;
00315         bi->bmiHeader.biPlanes      = 1;
00316         bi->bmiHeader.biBitCount    = 12;
00317         bi->bmiHeader.biCompression = MKTAG('I','4','2','0');
00318         bi->bmiHeader.biSizeImage   = 115200;
00319         dump_bih(s, &bi->bmiHeader);
00320     }
00321 
00322     ret = SendMessage(ctx->hwnd, WM_CAP_SET_VIDEOFORMAT, bisize, (LPARAM) bi);
00323     if(!ret) {
00324         av_log(s, AV_LOG_ERROR, "Could not set Video Format.\n");
00325         goto fail_bi;
00326     }
00327 
00328     biCompression = bi->bmiHeader.biCompression;
00329     biBitCount = bi->bmiHeader.biBitCount;
00330 
00331     av_free(bi);
00332 
00333     /* Set sequence setup */
00334     ret = SendMessage(ctx->hwnd, WM_CAP_GET_SEQUENCE_SETUP, sizeof(cparms),
00335                       (LPARAM) &cparms);
00336     if(!ret)
00337         goto fail_io;
00338 
00339     dump_captureparms(s, &cparms);
00340 
00341     cparms.fYield = 1; // Spawn a background thread
00342     cparms.dwRequestMicroSecPerFrame =
00343                                (ap->time_base.num*1000000) / ap->time_base.den;
00344     cparms.fAbortLeftMouse = 0;
00345     cparms.fAbortRightMouse = 0;
00346     cparms.fCaptureAudio = 0;
00347     cparms.vKeyAbort = 0;
00348 
00349     ret = SendMessage(ctx->hwnd, WM_CAP_SET_SEQUENCE_SETUP, sizeof(cparms),
00350                       (LPARAM) &cparms);
00351     if(!ret)
00352         goto fail_io;
00353 
00354     codec = st->codec;
00355     codec->time_base = ap->time_base;
00356     codec->codec_type = AVMEDIA_TYPE_VIDEO;
00357     codec->width = width;
00358     codec->height = height;
00359     codec->pix_fmt = vfw_pixfmt(biCompression, biBitCount);
00360     if(codec->pix_fmt == PIX_FMT_NONE) {
00361         codec->codec_id = vfw_codecid(biCompression);
00362         if(codec->codec_id == CODEC_ID_NONE) {
00363             av_log(s, AV_LOG_ERROR, "Unknown compression type. "
00364                              "Please report verbose (-v 9) debug information.\n");
00365             vfw_read_close(s);
00366             return AVERROR_PATCHWELCOME;
00367         }
00368         codec->bits_per_coded_sample = biBitCount;
00369     } else {
00370         codec->codec_id = CODEC_ID_RAWVIDEO;
00371         if(biCompression == BI_RGB) {
00372             codec->bits_per_coded_sample = biBitCount;
00373             codec->extradata = av_malloc(9 + FF_INPUT_BUFFER_PADDING_SIZE);
00374             if (codec->extradata) {
00375                 codec->extradata_size = 9;
00376                 memcpy(codec->extradata, "BottomUp", 9);
00377             }
00378         }
00379     }
00380 
00381     av_set_pts_info(st, 32, 1, 1000);
00382 
00383     ctx->mutex = CreateMutex(NULL, 0, NULL);
00384     if(!ctx->mutex) {
00385         av_log(s, AV_LOG_ERROR, "Could not create Mutex.\n" );
00386         goto fail_io;
00387     }
00388     ctx->event = CreateEvent(NULL, 1, 0, NULL);
00389     if(!ctx->event) {
00390         av_log(s, AV_LOG_ERROR, "Could not create Event.\n" );
00391         goto fail_io;
00392     }
00393 
00394     ret = SendMessage(ctx->hwnd, WM_CAP_SEQUENCE_NOFILE, 0, 0);
00395     if(!ret) {
00396         av_log(s, AV_LOG_ERROR, "Could not start capture sequence.\n" );
00397         goto fail_io;
00398     }
00399 
00400     return 0;
00401 
00402 fail_bi:
00403     av_free(bi);
00404 
00405 fail_io:
00406     vfw_read_close(s);
00407     return AVERROR(EIO);
00408 }
00409 
00410 static int vfw_read_packet(AVFormatContext *s, AVPacket *pkt)
00411 {
00412     struct vfw_ctx *ctx = s->priv_data;
00413     AVPacketList *pktl = NULL;
00414 
00415     while(!pktl) {
00416         WaitForSingleObject(ctx->mutex, INFINITE);
00417         pktl = ctx->pktl;
00418         if(ctx->pktl) {
00419             *pkt = ctx->pktl->pkt;
00420             ctx->pktl = ctx->pktl->next;
00421             av_free(pktl);
00422         }
00423         ResetEvent(ctx->event);
00424         ReleaseMutex(ctx->mutex);
00425         if(!pktl) {
00426             if(s->flags & AVFMT_FLAG_NONBLOCK) {
00427                 return AVERROR(EAGAIN);
00428             } else {
00429                 WaitForSingleObject(ctx->event, INFINITE);
00430             }
00431         }
00432     }
00433 
00434     ctx->curbufsize -= pkt->size;
00435 
00436     return pkt->size;
00437 }
00438 
00439 AVInputFormat vfwcap_demuxer = {
00440     "vfwcap",
00441     NULL_IF_CONFIG_SMALL("VFW video capture"),
00442     sizeof(struct vfw_ctx),
00443     NULL,
00444     vfw_read_header,
00445     vfw_read_packet,
00446     vfw_read_close,
00447     .flags = AVFMT_NOFILE,
00448 };

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