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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     AVFormatContext *s;
00042     unsigned int curbufsize;
00043     unsigned int frame_num;
00044 };
00045 
00046 static enum PixelFormat vfw_pixfmt(DWORD biCompression, WORD biBitCount)
00047 {
00048     switch(biCompression) {
00049     case MKTAG('Y', 'U', 'Y', '2'):
00050         return PIX_FMT_YUYV422;
00051     case MKTAG('I', '4', '2', '0'):
00052         return PIX_FMT_YUV420P;
00053     case BI_RGB:
00054         switch(biBitCount) { /* 1-8 are untested */
00055             case 1:
00056                 return PIX_FMT_MONOWHITE;
00057             case 4:
00058                 return PIX_FMT_RGB4;
00059             case 8:
00060                 return PIX_FMT_RGB8;
00061             case 16:
00062                 return PIX_FMT_RGB555;
00063             case 24:
00064                 return PIX_FMT_BGR24;
00065             case 32:
00066                 return PIX_FMT_RGB32;
00067         }
00068     }
00069     return -1;
00070 }
00071 
00072 #define dstruct(pctx, sname, var, type) \
00073     av_log(pctx, AV_LOG_DEBUG, #var":\t%"type"\n", sname->var)
00074 
00075 static void dump_captureparms(AVFormatContext *s, CAPTUREPARMS *cparms)
00076 {
00077     av_log(s, AV_LOG_DEBUG, "CAPTUREPARMS\n");
00078     dstruct(s, cparms, dwRequestMicroSecPerFrame, "lu");
00079     dstruct(s, cparms, fMakeUserHitOKToCapture, "d");
00080     dstruct(s, cparms, wPercentDropForError, "u");
00081     dstruct(s, cparms, fYield, "d");
00082     dstruct(s, cparms, dwIndexSize, "lu");
00083     dstruct(s, cparms, wChunkGranularity, "u");
00084     dstruct(s, cparms, fUsingDOSMemory, "d");
00085     dstruct(s, cparms, wNumVideoRequested, "u");
00086     dstruct(s, cparms, fCaptureAudio, "d");
00087     dstruct(s, cparms, wNumAudioRequested, "u");
00088     dstruct(s, cparms, vKeyAbort, "u");
00089     dstruct(s, cparms, fAbortLeftMouse, "d");
00090     dstruct(s, cparms, fAbortRightMouse, "d");
00091     dstruct(s, cparms, fLimitEnabled, "d");
00092     dstruct(s, cparms, wTimeLimit, "u");
00093     dstruct(s, cparms, fMCIControl, "d");
00094     dstruct(s, cparms, fStepMCIDevice, "d");
00095     dstruct(s, cparms, dwMCIStartTime, "lu");
00096     dstruct(s, cparms, dwMCIStopTime, "lu");
00097     dstruct(s, cparms, fStepCaptureAt2x, "d");
00098     dstruct(s, cparms, wStepCaptureAverageFrames, "u");
00099     dstruct(s, cparms, dwAudioBufferSize, "lu");
00100     dstruct(s, cparms, fDisableWriteCache, "d");
00101     dstruct(s, cparms, AVStreamMaster, "u");
00102 }
00103 
00104 static void dump_videohdr(AVFormatContext *s, VIDEOHDR *vhdr)
00105 {
00106 #ifdef DEBUG_VFW
00107     av_log(s, AV_LOG_DEBUG, "VIDEOHDR\n");
00108     dstruct(s, vhdr, lpData, "p");
00109     dstruct(s, vhdr, dwBufferLength, "lu");
00110     dstruct(s, vhdr, dwBytesUsed, "lu");
00111     dstruct(s, vhdr, dwTimeCaptured, "lu");
00112     dstruct(s, vhdr, dwUser, "lu");
00113     dstruct(s, vhdr, dwFlags, "lu");
00114     dstruct(s, vhdr, dwReserved[0], "lu");
00115     dstruct(s, vhdr, dwReserved[1], "lu");
00116     dstruct(s, vhdr, dwReserved[2], "lu");
00117     dstruct(s, vhdr, dwReserved[3], "lu");
00118 #endif
00119 }
00120 
00121 static void dump_bih(AVFormatContext *s, BITMAPINFOHEADER *bih)
00122 {
00123     av_log(s, AV_LOG_DEBUG, "BITMAPINFOHEADER\n");
00124     dstruct(s, bih, biSize, "lu");
00125     dstruct(s, bih, biWidth, "ld");
00126     dstruct(s, bih, biHeight, "ld");
00127     dstruct(s, bih, biPlanes, "d");
00128     dstruct(s, bih, biBitCount, "d");
00129     dstruct(s, bih, biCompression, "lu");
00130     av_log(s, AV_LOG_DEBUG, "    biCompression:\t\"%.4s\"\n",
00131                    (char*) &bih->biCompression);
00132     dstruct(s, bih, biSizeImage, "lu");
00133     dstruct(s, bih, biXPelsPerMeter, "lu");
00134     dstruct(s, bih, biYPelsPerMeter, "lu");
00135     dstruct(s, bih, biClrUsed, "lu");
00136     dstruct(s, bih, biClrImportant, "lu");
00137 }
00138 
00139 static int shall_we_drop(struct vfw_ctx *ctx)
00140 {
00141     AVFormatContext *s = ctx->s;
00142     const uint8_t dropscore[] = {62, 75, 87, 100};
00143     const int ndropscores = FF_ARRAY_ELEMS(dropscore);
00144     unsigned int buffer_fullness = (ctx->curbufsize*100)/s->max_picture_buffer;
00145 
00146     if(dropscore[++ctx->frame_num%ndropscores] <= buffer_fullness) {
00147         av_log(ctx->s, AV_LOG_ERROR,
00148               "real-time buffer %d%% full! frame dropped!\n", buffer_fullness);
00149         return 1;
00150     }
00151 
00152     return 0;
00153 }
00154 
00155 static LRESULT CALLBACK videostream_cb(HWND hwnd, LPVIDEOHDR vdhdr)
00156 {
00157     struct vfw_ctx *ctx;
00158     AVPacketList **ppktl, *pktl_next;
00159 
00160     ctx = (struct vfw_ctx *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
00161 
00162     dump_videohdr(ctx->s, vdhdr);
00163 
00164     if(shall_we_drop(ctx))
00165         return FALSE;
00166 
00167     WaitForSingleObject(ctx->mutex, INFINITE);
00168 
00169     pktl_next = av_mallocz(sizeof(AVPacketList));
00170     if(!pktl_next)
00171         goto fail;
00172 
00173     if(av_new_packet(&pktl_next->pkt, vdhdr->dwBytesUsed) < 0) {
00174         av_free(pktl_next);
00175         goto fail;
00176     }
00177 
00178     pktl_next->pkt.pts = vdhdr->dwTimeCaptured;
00179     memcpy(pktl_next->pkt.data, vdhdr->lpData, vdhdr->dwBytesUsed);
00180 
00181     for(ppktl = &ctx->pktl ; *ppktl ; ppktl = &(*ppktl)->next);
00182     *ppktl = pktl_next;
00183 
00184     ctx->curbufsize += vdhdr->dwBytesUsed;
00185 
00186     SetEvent(ctx->event);
00187     ReleaseMutex(ctx->mutex);
00188 
00189     return TRUE;
00190 fail:
00191     ReleaseMutex(ctx->mutex);
00192     return FALSE;
00193 }
00194 
00195 static int vfw_read_close(AVFormatContext *s);
00196 
00197 static int vfw_read_header(AVFormatContext *s, AVFormatParameters *ap)
00198 {
00199     struct vfw_ctx *ctx = s->priv_data;
00200     AVCodecContext *codec;
00201     AVStream *st;
00202     int devnum;
00203     int bisize;
00204     BITMAPINFO *bi;
00205     CAPTUREPARMS cparms;
00206     DWORD biCompression;
00207     WORD biBitCount;
00208     int width;
00209     int height;
00210     int ret;
00211 
00212     if(!ap->time_base.den) {
00213         av_log(s, AV_LOG_ERROR, "A time base must be specified.\n");
00214         return AVERROR_IO;
00215     }
00216 
00217     ctx->s = s;
00218 
00219     ctx->hwnd = capCreateCaptureWindow(NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
00220     if(!ctx->hwnd) {
00221         av_log(s, AV_LOG_ERROR, "Could not create capture window.\n");
00222         return AVERROR_IO;
00223     }
00224 
00225     /* If atoi fails, devnum==0 and the default device is used */
00226     devnum = atoi(s->filename);
00227 
00228     ret = SendMessage(ctx->hwnd, WM_CAP_DRIVER_CONNECT, devnum, 0);
00229     if(!ret) {
00230         av_log(s, AV_LOG_ERROR, "Could not connect to device.\n");
00231         DestroyWindow(ctx->hwnd);
00232         return AVERROR(ENODEV);
00233     }
00234 
00235     SendMessage(ctx->hwnd, WM_CAP_SET_OVERLAY, 0, 0);
00236     SendMessage(ctx->hwnd, WM_CAP_SET_PREVIEW, 0, 0);
00237 
00238     ret = SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0,
00239                       (LPARAM) videostream_cb);
00240     if(!ret) {
00241         av_log(s, AV_LOG_ERROR, "Could not set video stream callback.\n");
00242         goto fail_io;
00243     }
00244 
00245     SetWindowLongPtr(ctx->hwnd, GWLP_USERDATA, (LONG_PTR) ctx);
00246 
00247     st = av_new_stream(s, 0);
00248     if(!st) {
00249         vfw_read_close(s);
00250         return AVERROR_NOMEM;
00251     }
00252 
00253     /* Set video format */
00254     bisize = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, 0, 0);
00255     if(!bisize)
00256         goto fail_io;
00257     bi = av_malloc(bisize);
00258     if(!bi) {
00259         vfw_read_close(s);
00260         return AVERROR_NOMEM;
00261     }
00262     ret = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, bisize, (LPARAM) bi);
00263     if(!ret)
00264         goto fail_bi;
00265 
00266     dump_bih(s, &bi->bmiHeader);
00267 
00268     width  = ap->width  ? ap->width  : bi->bmiHeader.biWidth ;
00269     height = ap->height ? ap->height : bi->bmiHeader.biHeight;
00270     bi->bmiHeader.biWidth  = width ;
00271     bi->bmiHeader.biHeight = height;
00272 
00273 #if 0
00274     /* For testing yet unsupported compressions
00275      * Copy these values from user-supplied verbose information */
00276     bi->bmiHeader.biWidth       = 320;
00277     bi->bmiHeader.biHeight      = 240;
00278     bi->bmiHeader.biPlanes      = 1;
00279     bi->bmiHeader.biBitCount    = 12;
00280     bi->bmiHeader.biCompression = MKTAG('I','4','2','0');
00281     bi->bmiHeader.biSizeImage   = 115200;
00282     dump_bih(s, &bi->bmiHeader);
00283 #endif
00284 
00285     ret = SendMessage(ctx->hwnd, WM_CAP_SET_VIDEOFORMAT, bisize, (LPARAM) bi);
00286     if(!ret) {
00287         av_log(s, AV_LOG_ERROR, "Could not set Video Format.\n");
00288         goto fail_bi;
00289     }
00290 
00291     biCompression = bi->bmiHeader.biCompression;
00292     biBitCount = bi->bmiHeader.biBitCount;
00293 
00294     av_free(bi);
00295 
00296     /* Set sequence setup */
00297     ret = SendMessage(ctx->hwnd, WM_CAP_GET_SEQUENCE_SETUP, sizeof(cparms),
00298                       (LPARAM) &cparms);
00299     if(!ret)
00300         goto fail_io;
00301 
00302     dump_captureparms(s, &cparms);
00303 
00304     cparms.fYield = 1; // Spawn a background thread
00305     cparms.dwRequestMicroSecPerFrame =
00306                                (ap->time_base.num*1000000) / ap->time_base.den;
00307     cparms.fAbortLeftMouse = 0;
00308     cparms.fAbortRightMouse = 0;
00309     cparms.fCaptureAudio = 0;
00310     cparms.vKeyAbort = 0;
00311 
00312     ret = SendMessage(ctx->hwnd, WM_CAP_SET_SEQUENCE_SETUP, sizeof(cparms),
00313                       (LPARAM) &cparms);
00314     if(!ret)
00315         goto fail_io;
00316 
00317     codec = st->codec;
00318     codec->time_base = ap->time_base;
00319     codec->codec_type = CODEC_TYPE_VIDEO;
00320     codec->width = width;
00321     codec->height = height;
00322     codec->codec_id = CODEC_ID_RAWVIDEO;
00323     codec->pix_fmt = vfw_pixfmt(biCompression, biBitCount);
00324     if(biCompression == BI_RGB)
00325         codec->bits_per_coded_sample = biBitCount;
00326 
00327     av_set_pts_info(st, 32, 1, 1000);
00328 
00329     if(codec->pix_fmt == -1) {
00330         av_log(s, AV_LOG_ERROR, "Unknown compression type."
00331                          "Please report verbose (-v 99) debug information.\n");
00332         vfw_read_close(s);
00333         return AVERROR_PATCHWELCOME;
00334     }
00335 
00336     ctx->mutex = CreateMutex(NULL, 0, NULL);
00337     if(!ctx->mutex) {
00338         av_log(s, AV_LOG_ERROR, "Could not create Mutex.\n" );
00339         goto fail_io;
00340     }
00341     ctx->event = CreateEvent(NULL, 1, 0, NULL);
00342     if(!ctx->event) {
00343         av_log(s, AV_LOG_ERROR, "Could not create Event.\n" );
00344         goto fail_io;
00345     }
00346 
00347     ret = SendMessage(ctx->hwnd, WM_CAP_SEQUENCE_NOFILE, 0, 0);
00348     if(!ret) {
00349         av_log(s, AV_LOG_ERROR, "Could not start capture sequence.\n" );
00350         goto fail_io;
00351     }
00352 
00353     return 0;
00354 
00355 fail_bi:
00356     av_free(bi);
00357 
00358 fail_io:
00359     vfw_read_close(s);
00360     return AVERROR_IO;
00361 }
00362 
00363 static int vfw_read_packet(AVFormatContext *s, AVPacket *pkt)
00364 {
00365     struct vfw_ctx *ctx = s->priv_data;
00366     AVPacketList *pktl = NULL;
00367 
00368     while(!pktl) {
00369         WaitForSingleObject(ctx->mutex, INFINITE);
00370         pktl = ctx->pktl;
00371         if(ctx->pktl) {
00372             *pkt = ctx->pktl->pkt;
00373             ctx->pktl = ctx->pktl->next;
00374             av_free(pktl);
00375         }
00376         ResetEvent(ctx->event);
00377         ReleaseMutex(ctx->mutex);
00378         if(!pktl) {
00379             if(s->flags & AVFMT_FLAG_NONBLOCK) {
00380                 return AVERROR(EAGAIN);
00381             } else {
00382                 WaitForSingleObject(ctx->event, INFINITE);
00383             }
00384         }
00385     }
00386 
00387     ctx->curbufsize -= pkt->size;
00388 
00389     return pkt->size;
00390 }
00391 
00392 static int vfw_read_close(AVFormatContext *s)
00393 {
00394     struct vfw_ctx *ctx = s->priv_data;
00395 
00396     if(ctx->hwnd) {
00397         SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
00398         SendMessage(ctx->hwnd, WM_CAP_DRIVER_DISCONNECT, 0, 0);
00399         DestroyWindow(ctx->hwnd);
00400     }
00401     if(ctx->mutex)
00402         CloseHandle(ctx->mutex);
00403     if(ctx->event)
00404         CloseHandle(ctx->event);
00405 
00406     return 0;
00407 }
00408 
00409 AVInputFormat vfwcap_demuxer = {
00410     "vfwcap",
00411     NULL_IF_CONFIG_SMALL("VFW video capture"),
00412     sizeof(struct vfw_ctx),
00413     NULL,
00414     vfw_read_header,
00415     vfw_read_packet,
00416     vfw_read_close,
00417     .flags = AVFMT_NOFILE,
00418 };

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