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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/internal.h"
00023 #include "libavutil/log.h"
00024 #include "libavutil/opt.h"
00025 #include "libavutil/parseutils.h"
00026 #include <windows.h>
00027 #include <vfw.h>
00028 #include "avdevice.h"
00029 
00030 /* Defines for VFW missing from MinGW.
00031  * Remove this when MinGW incorporates them. */
00032 #define HWND_MESSAGE                ((HWND)-3)
00033 
00034 /* End of missing MinGW defines */
00035 
00036 struct vfw_ctx {
00037     const AVClass *class;
00038     HWND hwnd;
00039     HANDLE mutex;
00040     HANDLE event;
00041     AVPacketList *pktl;
00042     unsigned int curbufsize;
00043     unsigned int frame_num;
00044     char *video_size;       
00045     char *framerate;        
00046 };
00047 
00048 static enum PixelFormat vfw_pixfmt(DWORD biCompression, WORD biBitCount)
00049 {
00050     switch(biCompression) {
00051     case MKTAG('U', 'Y', 'V', 'Y'):
00052         return PIX_FMT_UYVY422;
00053     case MKTAG('Y', 'U', 'Y', '2'):
00054         return PIX_FMT_YUYV422;
00055     case MKTAG('I', '4', '2', '0'):
00056         return PIX_FMT_YUV420P;
00057     case BI_RGB:
00058         switch(biBitCount) { /* 1-8 are untested */
00059             case 1:
00060                 return PIX_FMT_MONOWHITE;
00061             case 4:
00062                 return PIX_FMT_RGB4;
00063             case 8:
00064                 return PIX_FMT_RGB8;
00065             case 16:
00066                 return PIX_FMT_RGB555;
00067             case 24:
00068                 return PIX_FMT_BGR24;
00069             case 32:
00070                 return PIX_FMT_RGB32;
00071         }
00072     }
00073     return PIX_FMT_NONE;
00074 }
00075 
00076 static enum CodecID vfw_codecid(DWORD biCompression)
00077 {
00078     switch(biCompression) {
00079     case MKTAG('d', 'v', 's', 'd'):
00080         return CODEC_ID_DVVIDEO;
00081     case MKTAG('M', 'J', 'P', 'G'):
00082     case MKTAG('m', 'j', 'p', 'g'):
00083         return CODEC_ID_MJPEG;
00084     }
00085     return CODEC_ID_NONE;
00086 }
00087 
00088 #define dstruct(pctx, sname, var, type) \
00089     av_log(pctx, AV_LOG_DEBUG, #var":\t%"type"\n", sname->var)
00090 
00091 static void dump_captureparms(AVFormatContext *s, CAPTUREPARMS *cparms)
00092 {
00093     av_log(s, AV_LOG_DEBUG, "CAPTUREPARMS\n");
00094     dstruct(s, cparms, dwRequestMicroSecPerFrame, "lu");
00095     dstruct(s, cparms, fMakeUserHitOKToCapture, "d");
00096     dstruct(s, cparms, wPercentDropForError, "u");
00097     dstruct(s, cparms, fYield, "d");
00098     dstruct(s, cparms, dwIndexSize, "lu");
00099     dstruct(s, cparms, wChunkGranularity, "u");
00100     dstruct(s, cparms, fUsingDOSMemory, "d");
00101     dstruct(s, cparms, wNumVideoRequested, "u");
00102     dstruct(s, cparms, fCaptureAudio, "d");
00103     dstruct(s, cparms, wNumAudioRequested, "u");
00104     dstruct(s, cparms, vKeyAbort, "u");
00105     dstruct(s, cparms, fAbortLeftMouse, "d");
00106     dstruct(s, cparms, fAbortRightMouse, "d");
00107     dstruct(s, cparms, fLimitEnabled, "d");
00108     dstruct(s, cparms, wTimeLimit, "u");
00109     dstruct(s, cparms, fMCIControl, "d");
00110     dstruct(s, cparms, fStepMCIDevice, "d");
00111     dstruct(s, cparms, dwMCIStartTime, "lu");
00112     dstruct(s, cparms, dwMCIStopTime, "lu");
00113     dstruct(s, cparms, fStepCaptureAt2x, "d");
00114     dstruct(s, cparms, wStepCaptureAverageFrames, "u");
00115     dstruct(s, cparms, dwAudioBufferSize, "lu");
00116     dstruct(s, cparms, fDisableWriteCache, "d");
00117     dstruct(s, cparms, AVStreamMaster, "u");
00118 }
00119 
00120 static void dump_videohdr(AVFormatContext *s, VIDEOHDR *vhdr)
00121 {
00122 #ifdef DEBUG
00123     av_log(s, AV_LOG_DEBUG, "VIDEOHDR\n");
00124     dstruct(s, vhdr, lpData, "p");
00125     dstruct(s, vhdr, dwBufferLength, "lu");
00126     dstruct(s, vhdr, dwBytesUsed, "lu");
00127     dstruct(s, vhdr, dwTimeCaptured, "lu");
00128     dstruct(s, vhdr, dwUser, "lu");
00129     dstruct(s, vhdr, dwFlags, "lu");
00130     dstruct(s, vhdr, dwReserved[0], "lu");
00131     dstruct(s, vhdr, dwReserved[1], "lu");
00132     dstruct(s, vhdr, dwReserved[2], "lu");
00133     dstruct(s, vhdr, dwReserved[3], "lu");
00134 #endif
00135 }
00136 
00137 static void dump_bih(AVFormatContext *s, BITMAPINFOHEADER *bih)
00138 {
00139     av_log(s, AV_LOG_DEBUG, "BITMAPINFOHEADER\n");
00140     dstruct(s, bih, biSize, "lu");
00141     dstruct(s, bih, biWidth, "ld");
00142     dstruct(s, bih, biHeight, "ld");
00143     dstruct(s, bih, biPlanes, "d");
00144     dstruct(s, bih, biBitCount, "d");
00145     dstruct(s, bih, biCompression, "lu");
00146     av_log(s, AV_LOG_DEBUG, "    biCompression:\t\"%.4s\"\n",
00147                    (char*) &bih->biCompression);
00148     dstruct(s, bih, biSizeImage, "lu");
00149     dstruct(s, bih, biXPelsPerMeter, "lu");
00150     dstruct(s, bih, biYPelsPerMeter, "lu");
00151     dstruct(s, bih, biClrUsed, "lu");
00152     dstruct(s, bih, biClrImportant, "lu");
00153 }
00154 
00155 static int shall_we_drop(AVFormatContext *s)
00156 {
00157     struct vfw_ctx *ctx = s->priv_data;
00158     const uint8_t dropscore[] = {62, 75, 87, 100};
00159     const int ndropscores = FF_ARRAY_ELEMS(dropscore);
00160     unsigned int buffer_fullness = (ctx->curbufsize*100)/s->max_picture_buffer;
00161 
00162     if(dropscore[++ctx->frame_num%ndropscores] <= buffer_fullness) {
00163         av_log(s, AV_LOG_ERROR,
00164               "real-time buffer %d%% full! frame dropped!\n", buffer_fullness);
00165         return 1;
00166     }
00167 
00168     return 0;
00169 }
00170 
00171 static LRESULT CALLBACK videostream_cb(HWND hwnd, LPVIDEOHDR vdhdr)
00172 {
00173     AVFormatContext *s;
00174     struct vfw_ctx *ctx;
00175     AVPacketList **ppktl, *pktl_next;
00176 
00177     s = (AVFormatContext *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
00178     ctx = s->priv_data;
00179 
00180     dump_videohdr(s, vdhdr);
00181 
00182     if(shall_we_drop(s))
00183         return FALSE;
00184 
00185     WaitForSingleObject(ctx->mutex, INFINITE);
00186 
00187     pktl_next = av_mallocz(sizeof(AVPacketList));
00188     if(!pktl_next)
00189         goto fail;
00190 
00191     if(av_new_packet(&pktl_next->pkt, vdhdr->dwBytesUsed) < 0) {
00192         av_free(pktl_next);
00193         goto fail;
00194     }
00195 
00196     pktl_next->pkt.pts = vdhdr->dwTimeCaptured;
00197     memcpy(pktl_next->pkt.data, vdhdr->lpData, vdhdr->dwBytesUsed);
00198 
00199     for(ppktl = &ctx->pktl ; *ppktl ; ppktl = &(*ppktl)->next);
00200     *ppktl = pktl_next;
00201 
00202     ctx->curbufsize += vdhdr->dwBytesUsed;
00203 
00204     SetEvent(ctx->event);
00205     ReleaseMutex(ctx->mutex);
00206 
00207     return TRUE;
00208 fail:
00209     ReleaseMutex(ctx->mutex);
00210     return FALSE;
00211 }
00212 
00213 static int vfw_read_close(AVFormatContext *s)
00214 {
00215     struct vfw_ctx *ctx = s->priv_data;
00216     AVPacketList *pktl;
00217 
00218     if(ctx->hwnd) {
00219         SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
00220         SendMessage(ctx->hwnd, WM_CAP_DRIVER_DISCONNECT, 0, 0);
00221         DestroyWindow(ctx->hwnd);
00222     }
00223     if(ctx->mutex)
00224         CloseHandle(ctx->mutex);
00225     if(ctx->event)
00226         CloseHandle(ctx->event);
00227 
00228     pktl = ctx->pktl;
00229     while (pktl) {
00230         AVPacketList *next = pktl->next;
00231         av_destruct_packet(&pktl->pkt);
00232         av_free(pktl);
00233         pktl = next;
00234     }
00235 
00236     return 0;
00237 }
00238 
00239 static int vfw_read_header(AVFormatContext *s, AVFormatParameters *ap)
00240 {
00241     struct vfw_ctx *ctx = s->priv_data;
00242     AVCodecContext *codec;
00243     AVStream *st;
00244     int devnum;
00245     int bisize;
00246     BITMAPINFO *bi = NULL;
00247     CAPTUREPARMS cparms;
00248     DWORD biCompression;
00249     WORD biBitCount;
00250     int ret;
00251     AVRational framerate_q;
00252 
00253     if (!strcmp(s->filename, "list")) {
00254         for (devnum = 0; devnum <= 9; devnum++) {
00255             char driver_name[256];
00256             char driver_ver[256];
00257             ret = capGetDriverDescription(devnum,
00258                                           driver_name, sizeof(driver_name),
00259                                           driver_ver, sizeof(driver_ver));
00260             if (ret) {
00261                 av_log(s, AV_LOG_INFO, "Driver %d\n", devnum);
00262                 av_log(s, AV_LOG_INFO, " %s\n", driver_name);
00263                 av_log(s, AV_LOG_INFO, " %s\n", driver_ver);
00264             }
00265         }
00266         return AVERROR(EIO);
00267     }
00268 
00269     ctx->hwnd = capCreateCaptureWindow(NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
00270     if(!ctx->hwnd) {
00271         av_log(s, AV_LOG_ERROR, "Could not create capture window.\n");
00272         return AVERROR(EIO);
00273     }
00274 
00275     /* If atoi fails, devnum==0 and the default device is used */
00276     devnum = atoi(s->filename);
00277 
00278     ret = SendMessage(ctx->hwnd, WM_CAP_DRIVER_CONNECT, devnum, 0);
00279     if(!ret) {
00280         av_log(s, AV_LOG_ERROR, "Could not connect to device.\n");
00281         DestroyWindow(ctx->hwnd);
00282         return AVERROR(ENODEV);
00283     }
00284 
00285     SendMessage(ctx->hwnd, WM_CAP_SET_OVERLAY, 0, 0);
00286     SendMessage(ctx->hwnd, WM_CAP_SET_PREVIEW, 0, 0);
00287 
00288     ret = SendMessage(ctx->hwnd, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0,
00289                       (LPARAM) videostream_cb);
00290     if(!ret) {
00291         av_log(s, AV_LOG_ERROR, "Could not set video stream callback.\n");
00292         goto fail;
00293     }
00294 
00295     SetWindowLongPtr(ctx->hwnd, GWLP_USERDATA, (LONG_PTR) s);
00296 
00297     st = avformat_new_stream(s, NULL);
00298     if(!st) {
00299         vfw_read_close(s);
00300         return AVERROR(ENOMEM);
00301     }
00302 
00303     /* Set video format */
00304     bisize = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, 0, 0);
00305     if(!bisize)
00306         goto fail;
00307     bi = av_malloc(bisize);
00308     if(!bi) {
00309         vfw_read_close(s);
00310         return AVERROR(ENOMEM);
00311     }
00312     ret = SendMessage(ctx->hwnd, WM_CAP_GET_VIDEOFORMAT, bisize, (LPARAM) bi);
00313     if(!ret)
00314         goto fail;
00315 
00316     dump_bih(s, &bi->bmiHeader);
00317 
00318     ret = av_parse_video_rate(&framerate_q, ctx->framerate);
00319     if (ret < 0) {
00320         av_log(s, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", ctx->framerate);
00321         goto fail;
00322     }
00323 
00324     if (ctx->video_size) {
00325         ret = av_parse_video_size(&bi->bmiHeader.biWidth, &bi->bmiHeader.biHeight, ctx->video_size);
00326         if (ret < 0) {
00327             av_log(s, AV_LOG_ERROR, "Couldn't parse video size.\n");
00328             goto fail;
00329         }
00330     }
00331 
00332     if (0) {
00333         /* For testing yet unsupported compressions
00334          * Copy these values from user-supplied verbose information */
00335         bi->bmiHeader.biWidth       = 320;
00336         bi->bmiHeader.biHeight      = 240;
00337         bi->bmiHeader.biPlanes      = 1;
00338         bi->bmiHeader.biBitCount    = 12;
00339         bi->bmiHeader.biCompression = MKTAG('I','4','2','0');
00340         bi->bmiHeader.biSizeImage   = 115200;
00341         dump_bih(s, &bi->bmiHeader);
00342     }
00343 
00344     ret = SendMessage(ctx->hwnd, WM_CAP_SET_VIDEOFORMAT, bisize, (LPARAM) bi);
00345     if(!ret) {
00346         av_log(s, AV_LOG_ERROR, "Could not set Video Format.\n");
00347         goto fail;
00348     }
00349 
00350     biCompression = bi->bmiHeader.biCompression;
00351     biBitCount = bi->bmiHeader.biBitCount;
00352 
00353     /* Set sequence setup */
00354     ret = SendMessage(ctx->hwnd, WM_CAP_GET_SEQUENCE_SETUP, sizeof(cparms),
00355                       (LPARAM) &cparms);
00356     if(!ret)
00357         goto fail;
00358 
00359     dump_captureparms(s, &cparms);
00360 
00361     cparms.fYield = 1; // Spawn a background thread
00362     cparms.dwRequestMicroSecPerFrame =
00363                                (framerate_q.den*1000000) / framerate_q.num;
00364     cparms.fAbortLeftMouse = 0;
00365     cparms.fAbortRightMouse = 0;
00366     cparms.fCaptureAudio = 0;
00367     cparms.vKeyAbort = 0;
00368 
00369     ret = SendMessage(ctx->hwnd, WM_CAP_SET_SEQUENCE_SETUP, sizeof(cparms),
00370                       (LPARAM) &cparms);
00371     if(!ret)
00372         goto fail;
00373 
00374     codec = st->codec;
00375     codec->time_base = (AVRational){framerate_q.den, framerate_q.num};
00376     codec->codec_type = AVMEDIA_TYPE_VIDEO;
00377     codec->width  = bi->bmiHeader.biWidth;
00378     codec->height = bi->bmiHeader.biHeight;
00379     codec->pix_fmt = vfw_pixfmt(biCompression, biBitCount);
00380     if(codec->pix_fmt == PIX_FMT_NONE) {
00381         codec->codec_id = vfw_codecid(biCompression);
00382         if(codec->codec_id == CODEC_ID_NONE) {
00383             av_log(s, AV_LOG_ERROR, "Unknown compression type. "
00384                              "Please report verbose (-v 9) debug information.\n");
00385             vfw_read_close(s);
00386             return AVERROR_PATCHWELCOME;
00387         }
00388         codec->bits_per_coded_sample = biBitCount;
00389     } else {
00390         codec->codec_id = CODEC_ID_RAWVIDEO;
00391         if(biCompression == BI_RGB) {
00392             codec->bits_per_coded_sample = biBitCount;
00393             codec->extradata = av_malloc(9 + FF_INPUT_BUFFER_PADDING_SIZE);
00394             if (codec->extradata) {
00395                 codec->extradata_size = 9;
00396                 memcpy(codec->extradata, "BottomUp", 9);
00397             }
00398         }
00399     }
00400 
00401     av_freep(&bi);
00402 
00403     avpriv_set_pts_info(st, 32, 1, 1000);
00404 
00405     ctx->mutex = CreateMutex(NULL, 0, NULL);
00406     if(!ctx->mutex) {
00407         av_log(s, AV_LOG_ERROR, "Could not create Mutex.\n" );
00408         goto fail;
00409     }
00410     ctx->event = CreateEvent(NULL, 1, 0, NULL);
00411     if(!ctx->event) {
00412         av_log(s, AV_LOG_ERROR, "Could not create Event.\n" );
00413         goto fail;
00414     }
00415 
00416     ret = SendMessage(ctx->hwnd, WM_CAP_SEQUENCE_NOFILE, 0, 0);
00417     if(!ret) {
00418         av_log(s, AV_LOG_ERROR, "Could not start capture sequence.\n" );
00419         goto fail;
00420     }
00421 
00422     return 0;
00423 
00424 fail:
00425     av_freep(&bi);
00426     vfw_read_close(s);
00427     return AVERROR(EIO);
00428 }
00429 
00430 static int vfw_read_packet(AVFormatContext *s, AVPacket *pkt)
00431 {
00432     struct vfw_ctx *ctx = s->priv_data;
00433     AVPacketList *pktl = NULL;
00434 
00435     while(!pktl) {
00436         WaitForSingleObject(ctx->mutex, INFINITE);
00437         pktl = ctx->pktl;
00438         if(ctx->pktl) {
00439             *pkt = ctx->pktl->pkt;
00440             ctx->pktl = ctx->pktl->next;
00441             av_free(pktl);
00442         }
00443         ResetEvent(ctx->event);
00444         ReleaseMutex(ctx->mutex);
00445         if(!pktl) {
00446             if(s->flags & AVFMT_FLAG_NONBLOCK) {
00447                 return AVERROR(EAGAIN);
00448             } else {
00449                 WaitForSingleObject(ctx->event, INFINITE);
00450             }
00451         }
00452     }
00453 
00454     ctx->curbufsize -= pkt->size;
00455 
00456     return pkt->size;
00457 }
00458 
00459 #define OFFSET(x) offsetof(struct vfw_ctx, x)
00460 #define DEC AV_OPT_FLAG_DECODING_PARAM
00461 static const AVOption options[] = {
00462     { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
00463     { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
00464     { NULL },
00465 };
00466 
00467 static const AVClass vfw_class = {
00468     .class_name = "VFW indev",
00469     .item_name  = av_default_item_name,
00470     .option     = options,
00471     .version    = LIBAVUTIL_VERSION_INT,
00472 };
00473 
00474 AVInputFormat ff_vfwcap_demuxer = {
00475     .name           = "vfwcap",
00476     .long_name      = NULL_IF_CONFIG_SMALL("VfW video capture"),
00477     .priv_data_size = sizeof(struct vfw_ctx),
00478     .read_header    = vfw_read_header,
00479     .read_packet    = vfw_read_packet,
00480     .read_close     = vfw_read_close,
00481     .flags          = AVFMT_NOFILE,
00482     .priv_class     = &vfw_class,
00483 };
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