static int grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) { VideoData *s = s1->priv_data; AVStream *st; int width, height; int video_fd, frame_size; int ret, frame_rate, frame_rate_base; int desired_palette, desired_depth; struct video_tuner tuner; struct video_audio audio; struct video_picture pict; int j; int vformat_num = sizeof(video_formats) / sizeof(video_formats[0]); if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) { av_log(s1, AV_LOG_ERROR, "Bad capture size (%dx%d) or wrong time base (%d)\n", ap->width, ap->height, ap->time_base.den); return -1; } width = ap->width; height = ap->height; frame_rate = ap->time_base.den; frame_rate_base = ap->time_base.num; if((unsigned)width > 32767 || (unsigned)height > 32767) { av_log(s1, AV_LOG_ERROR, "Capture size is out of range: %dx%d\n", width, height); return -1; } st = av_new_stream(s1, 0); if (!st) return AVERROR(ENOMEM); av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */ s->width = width; s->height = height; s->frame_rate = frame_rate; s->frame_rate_base = frame_rate_base; video_fd = open(s1->filename, O_RDWR); if (video_fd < 0) { av_log(s1, AV_LOG_ERROR, "%s: %s\n", s1->filename, strerror(errno)); goto fail; } if (ioctl(video_fd,VIDIOCGCAP, &s->video_cap) < 0) { av_log(s1, AV_LOG_ERROR, "VIDIOCGCAP: %s\n", strerror(errno)); goto fail; } if (!(s->video_cap.type & VID_TYPE_CAPTURE)) { av_log(s1, AV_LOG_ERROR, "Fatal: grab device does not handle capture\n"); goto fail; } desired_palette = -1; desired_depth = -1; for (j = 0; j < vformat_num; j++) { if (ap->pix_fmt == video_formats[j].pix_fmt) { desired_palette = video_formats[j].palette; desired_depth = video_formats[j].depth; break; } } /* set tv standard */ if (ap->standard && !ioctl(video_fd, VIDIOCGTUNER, &tuner)) { if (!strcasecmp(ap->standard, "pal")) tuner.mode = VIDEO_MODE_PAL; else if (!strcasecmp(ap->standard, "secam")) tuner.mode = VIDEO_MODE_SECAM; else tuner.mode = VIDEO_MODE_NTSC; ioctl(video_fd, VIDIOCSTUNER, &tuner); } /* unmute audio */ audio.audio = 0; ioctl(video_fd, VIDIOCGAUDIO, &audio); memcpy(&s->audio_saved, &audio, sizeof(audio)); audio.flags &= ~VIDEO_AUDIO_MUTE; ioctl(video_fd, VIDIOCSAUDIO, &audio); ioctl(video_fd, VIDIOCGPICT, &pict); #if 0 printf("v4l: colour=%d hue=%d brightness=%d constrast=%d whiteness=%d\n", pict.colour, pict.hue, pict.brightness, pict.contrast, pict.whiteness); #endif /* try to choose a suitable video format */ pict.palette = desired_palette; pict.depth= desired_depth; if (desired_palette == -1 || (ret = ioctl(video_fd, VIDIOCSPICT, &pict)) < 0) { for (j = 0; j < vformat_num; j++) { pict.palette = video_formats[j].palette; pict.depth = video_formats[j].depth; if (-1 != ioctl(video_fd, VIDIOCSPICT, &pict)) break; } if (j >= vformat_num) goto fail1; } ret = ioctl(video_fd,VIDIOCGMBUF,&s->gb_buffers); if (ret < 0) { /* try to use read based access */ struct video_window win; int val; win.x = 0; win.y = 0; win.width = width; win.height = height; win.chromakey = -1; win.flags = 0; ioctl(video_fd, VIDIOCSWIN, &win); s->frame_format = pict.palette; val = 1; ioctl(video_fd, VIDIOCCAPTURE, &val); s->time_frame = av_gettime() * s->frame_rate / s->frame_rate_base; s->use_mmap = 0; } else { s->video_buf = mmap(0,s->gb_buffers.size,PROT_READ|PROT_WRITE,MAP_SHARED,video_fd,0); if ((unsigned char*)-1 == s->video_buf) { s->video_buf = mmap(0,s->gb_buffers.size,PROT_READ|PROT_WRITE,MAP_PRIVATE,video_fd,0); if ((unsigned char*)-1 == s->video_buf) { av_log(s1, AV_LOG_ERROR, "mmap: %s\n", strerror(errno)); goto fail; } } s->gb_frame = 0; s->time_frame = av_gettime() * s->frame_rate / s->frame_rate_base; /* start to grab the first frame */ s->gb_buf.frame = s->gb_frame % s->gb_buffers.frames; s->gb_buf.height = height; s->gb_buf.width = width; s->gb_buf.format = pict.palette; ret = ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf); if (ret < 0) { if (errno != EAGAIN) { fail1: av_log(s1, AV_LOG_ERROR, "Fatal: grab device does not support suitable format\n"); } else { av_log(s1, AV_LOG_ERROR,"Fatal: grab device does not receive any video signal\n"); } goto fail; } for (j = 1; j < s->gb_buffers.frames; j++) { s->gb_buf.frame = j; ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf); } s->frame_format = s->gb_buf.format; s->use_mmap = 1; } for (j = 0; j < vformat_num; j++) { if (s->frame_format == video_formats[j].palette) { frame_size = width * height * video_formats[j].depth / 8; st->codec->pix_fmt = video_formats[j].pix_fmt; break; } } if (j >= vformat_num) goto fail; s->fd = video_fd; s->frame_size = frame_size; st->codec->codec_type = CODEC_TYPE_VIDEO; st->codec->codec_id = CODEC_ID_RAWVIDEO; st->codec->width = width; st->codec->height = height; st->codec->time_base.den = frame_rate; st->codec->time_base.num = frame_rate_base; st->codec->bit_rate = frame_size * 1/av_q2d(st->codec->time_base) * 8; return 0; fail: if (video_fd >= 0) close(video_fd); av_free(st); return AVERROR(EIO); }