Hi there,
I have two cards PV148H, one PV148HA and another PV148HB, each one has 4 bt878 chips and allows video capture at 25 fps on each video input. This allows me to have 8 video input using only 2 PCI cards. May problem is that I can capture video from the first card (the PV148HA), but form the second I get nothing. I read somewere that the first card used the video channel 0 and that the second used the video channel 1. My question is:
How can I change the video channel in the cards using the bttv2?
Currenty i use the VIDIOC_S_INPUT in order to change channel, but it apears not to be working right. Can someone take a look at my code and tell me what i'm doing wrong?
On Init the card:
int i,id,chroma_agc_id;
struct v4l2_control ctrl;
struct v4l2_queryctrl qc;
char str_std[20]="Chroma AGC";
fd = open(video_device, O_RDONLY);
if(fd<=0) { perror("open"); exit(-1); }
video_format = V4L2_PIX_FMT_BGR24;
cfmt.fmt.pix.width = video_width;
cfmt.fmt.pix.height = video_height;
cfmt.fmt.pix.depth = 24; //Paulino 16;
cfmt.fmt.pix.pixelformat = video_format;
cfmt.fmt.pix.flags = V4L2_FMT_FLAG_INTERLACED;
if (ioctl(fd, VIDIOC_S_FMT, &cfmt)) { perror("s_fmt"); exit(-1); }
if(cfmt.fmt.pix.pixelformat != video_format) { fprintf(stderr, "could not get necessary pixel format.\n");
exit(-1); }
// Here I change the channel that i want.... I suppose!!!
video_port = 0;
if (ioctl(fd,VIDIOC_S_INPUT,&video_port)) { perror("video_port"); exit(-1); };
video_width = cfmt.fmt.pix.width;
video_height = cfmt.fmt.pix.height;
video_frame_size = (video_width * video_height * cfmt.fmt.pix.depth)>>3;
fprintf(stderr, "capture got %ix%i(%i)\n", video_width, video_height, cfmt.fmt.pix.depth);
cparm.type = V4L2_BUF_TYPE_CAPTURE;
if (ioctl(fd, VIDIOC_G_PARM, &cparm) != 0) { perror("G_PARM"); exit(-1); }
video_frame_rate = cparm.parm.capture.timeperframe;
video_frame_rate = 10000000/video_frame_rate;
if(half_frame) video_frame_rate/=2;
fprintf(stderr, "Capturing at %f fps\n", video_frame_rate);
if (!READ)
{
crbuf.type = V4L2_BUF_TYPE_CAPTURE;
crbuf.count = BUFS;
if (ioctl(fd, VIDIOC_REQBUFS, &crbuf) != 0) { perror("REQBUF"); exit(-1); }
bufs = crbuf.count;
fprintf(stderr, "got %i buffers\n", bufs);
for(i=0; i<bufs; i++)
{
cbuf.type = V4L2_BUF_TYPE_CAPTURE;
cbuf.index = i;
if(ioctl(fd, VIDIOC_QUERYBUF, &cbuf)!=0) { perror("querybuf"); exit(-1); }
buf[i] = mmap(NULL, cbuf.length, PROT_READ, MAP_SHARED, fd, cbuf.offset);
if((int)(buf[i])==-1) { perror("mmap"); exit(-1); }
if(ioctl(fd, VIDIOC_QBUF, &cbuf)!=0) { perror("QBUF"); exit(-1); }
}
i = V4L2_BUF_TYPE_CAPTURE;
if(ioctl(fd, VIDIOC_STREAMON, &i)!=0) { perror("streamon"); exit(-1); }
}
ctrl.id=V4L2_CID_AUTOGAIN;
ctrl.value=0;
ioctl(fd,VIDIOC_S_CTRL,&ctrl);
ioctl(fd,VIDIOC_G_CTRL,&ctrl);
ctrl.id=V4L2_CID_AUTO_WHITE_BALANCE;
ctrl.value=0;
ioctl(fd,VIDIOC_S_CTRL,&ctrl);
ioctl(fd,VIDIOC_G_CTRL,&ctrl);
for (id = 0; id < 100; ++id)
{
qc.id = V4L2_CID_PRIVATE_BASE+id;
i = ioctl(fd, VIDIOC_QUERYCTRL, &qc);
if (i)
break;
if (strcmp(qc.name,str_std)==0) chroma_agc_id=id;
}
ctrl.id=V4L2_CID_PRIVATE_BASE+chroma_agc_id;
ctrl.value=0;
ioctl(fd,VIDIOC_S_CTRL,&ctrl);
ioctl(fd,VIDIOC_G_CTRL,&ctrl);
Thanks in advance
Maciel
