Chiebot-Mirror
/
opencv
mirror of https://github.com/opencv/opencv.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

allow changing FPS and Image Size using V4L2

Browse Source 
use logic similar to cap_libv4l: replace icvSetVideoSize by v4l2_reset
as it was not used for V4L1, the actual frame format is negotiated in
try_palette_v4l2 and the stream has to restarted anyway.
pull/5474/head
Pavel Rojtberg 9 years ago
parent 18034a5138
commit c0fe522c9d
1 changed files with 67 additions and 127 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 194
      modules/videoio/src/cap_v4l.cpp

194
modules/videoio/src/cap_v4l.cpp
Unescape View File

@ -244,6 +244,7 @@ make & enjoy!
/* Defaults - If your board can do better, set it here. Set for the most common type inputs. */
#define DEFAULT_V4L_WIDTH 640
#define DEFAULT_V4L_HEIGHT 480
#define DEFAULT_V4L_FPS 30
#define CHANNEL_NUMBER 1
#define MAX_CAMERAS 8
@ -315,6 +316,9 @@ typedef struct CvCaptureCAM_V4L
#ifdef HAVE_CAMV4L2
enum PALETTE_TYPE palette;
int index;
int width, height;
__u32 fps;
/* V4L2 variables */
buffer buffers[MAX_V4L_BUFFERS + 1];
struct v4l2_capability cap;
@ -373,8 +377,6 @@ static IplImage* icvRetrieveFrameCAM_V4L( CvCaptureCAM_V4L* capture, int );
static double icvGetPropertyCAM_V4L( CvCaptureCAM_V4L* capture, int property_id );
static int icvSetPropertyCAM_V4L( CvCaptureCAM_V4L* capture, int property_id, double value );
static int icvSetVideoSize( CvCaptureCAM_V4L* capture, int w, int h);
/*********************** Implementations ***************************************/
static int numCameras = 0;
@ -440,8 +442,8 @@ static int try_palette_v4l2(CvCaptureCAM_V4L* capture, unsigned long colorspace)
capture->form.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
capture->form.fmt.pix.pixelformat = colorspace;
capture->form.fmt.pix.field = V4L2_FIELD_ANY;
capture->form.fmt.pix.width = DEFAULT_V4L_WIDTH;
capture->form.fmt.pix.height = DEFAULT_V4L_HEIGHT;
capture->form.fmt.pix.width = capture->width;
capture->form.fmt.pix.height = capture->height;
if (-1 == ioctl (capture->deviceHandle, VIDIOC_S_FMT, &capture->form))
return -1;
@ -725,8 +727,21 @@ static void v4l2_scan_controls(CvCaptureCAM_V4L* capture)
v4l2_control_range(capture, V4L2_CID_FOCUS_ABSOLUTE);
}
static int _capture_V4L2 (CvCaptureCAM_V4L *capture, char *deviceName)
static int v4l2_set_fps(CvCaptureCAM_V4L* capture) {
v4l2_streamparm setfps;
CLEAR(setfps);
setfps.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
setfps.parm.capture.timeperframe.numerator = 1;
setfps.parm.capture.timeperframe.denominator = capture->fps;
return ioctl (capture->deviceHandle, VIDIOC_S_PARM, &setfps);
}
static int _capture_V4L2 (CvCaptureCAM_V4L *capture)
{
char deviceName[MAX_DEVICE_DRIVER_NAME];
/* Print the CameraNumber at the end of the string with a width of one character */
sprintf(deviceName, "/dev/video%1d", capture->index);
if (try_init_v4l2(capture, deviceName) != 1) {
/* init of the v4l2 device is not OK */
return -1;
@ -777,14 +792,11 @@ static int _capture_V4L2 (CvCaptureCAM_V4L *capture, char *deviceName)
return -1;
}
if (V4L2_SUPPORT == 0)
{
}
if (autosetup_capture_mode_v4l2(capture) == -1)
return -1;
icvSetVideoSize(capture, DEFAULT_V4L_WIDTH, DEFAULT_V4L_HEIGHT);
/* try to set framerate */
v4l2_set_fps(capture);
unsigned int min;
@ -887,9 +899,22 @@ static int _capture_V4L2 (CvCaptureCAM_V4L *capture, char *deviceName)
/* Allocate space for RGBA data */
capture->frame.imageData = (char *)cvAlloc(capture->frame.imageSize);
// reinitialize buffers
capture->FirstCapture = 1;
return 1;
}; /* End _capture_V4L2 */
/**
* some properties can not be changed while the device is in streaming mode.
* this method closes and re-opens the device to re-start the stream.
* this also causes buffers to be reallocated if the frame size was changed.
*/
static int v4l2_reset( CvCaptureCAM_V4L* capture) {
icvCloseCAM_V4L(capture);
return _capture_V4L2(capture);
}
#endif /* HAVE_CAMV4L2 */
#ifdef HAVE_CAMV4L
@ -1019,8 +1044,6 @@ static CvCaptureCAM_V4L * icvCaptureFromCAM_V4L (int index)
static int autoindex;
autoindex = 0;
char deviceName[MAX_DEVICE_DRIVER_NAME];
if (!numCameras)
icvInitCapture_V4L(); /* Havent called icvInitCapture yet - do it now! */
if (!numCameras)
@ -1049,8 +1072,7 @@ static CvCaptureCAM_V4L * icvCaptureFromCAM_V4L (int index)
index=autoindex;
autoindex++;// i can recall icvOpenCAM_V4l with index=-1 for next camera
}
/* Print the CameraNumber at the end of the string with a width of one character */
sprintf(deviceName, "/dev/video%1d", index);
capture->index = index;
/* w/o memset some parts arent initialized - AKA: Fill it with zeros so it is clean */
memset(capture,0,sizeof(CvCaptureCAM_V4L));
@ -1059,19 +1081,25 @@ static CvCaptureCAM_V4L * icvCaptureFromCAM_V4L (int index)
capture->FirstCapture = 1;
#ifdef HAVE_CAMV4L2
if (_capture_V4L2 (capture, deviceName) == -1) {
capture->width = DEFAULT_V4L_WIDTH;
capture->height = DEFAULT_V4L_HEIGHT;
capture->fps = DEFAULT_V4L_FPS;
if (_capture_V4L2 (capture) == -1) {
icvCloseCAM_V4L(capture);
V4L2_SUPPORT = 0;
#endif /* HAVE_CAMV4L2 */
#ifdef HAVE_CAMV4L
char deviceName[MAX_DEVICE_DRIVER_NAME];
/* Print the CameraNumber at the end of the string with a width of one character */
sprintf(deviceName, "/dev/video%1d", capture->index);
if (_capture_V4L (capture, deviceName) == -1) {
icvCloseCAM_V4L(capture);
return NULL;
}
#endif /* HAVE_CAMV4L */
#ifdef HAVE_CAMV4L2
} else {
V4L2_SUPPORT = 1;
}
#endif /* HAVE_CAMV4L2 */
@ -2247,6 +2275,18 @@ static double icvGetPropertyCAM_V4L (CvCaptureCAM_V4L* capture,
return capture->form.fmt.pix.height;
}
if(property_id == CV_CAP_PROP_FPS) {
struct v4l2_streamparm sp;
CLEAR(sp);
sp.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (ioctl(capture->deviceHandle, VIDIOC_G_PARM, &sp) < 0){
fprintf(stderr, "VIDEOIO ERROR: V4L: Unable to get camera FPS\n");
return -1;
}
return sp.parm.capture.timeperframe.denominator / (double)sp.parm.capture.timeperframe.numerator;
}
/* initialize the control structure */
if(property_id == CV_CAP_PROP_POS_MSEC) {
@ -2376,113 +2416,6 @@ static double icvGetPropertyCAM_V4L (CvCaptureCAM_V4L* capture,
};
static int icvSetVideoSize( CvCaptureCAM_V4L* capture, int w, int h) {
#ifdef HAVE_CAMV4L2
if (V4L2_SUPPORT == 1)
{
CLEAR (capture->cropcap);
capture->cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (ioctl (capture->deviceHandle, VIDIOC_CROPCAP, &capture->cropcap) < 0) {
fprintf(stderr, "VIDEOIO ERROR: V4L/V4L2: VIDIOC_CROPCAP\n");
} else {
CLEAR (capture->crop);
capture->crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
capture->crop.c= capture->cropcap.defrect;
/* set the crop area, but don't exit if the device don't support croping */
if (ioctl (capture->deviceHandle, VIDIOC_S_CROP, &capture->crop) < 0) {
fprintf(stderr, "VIDEOIO ERROR: V4L/V4L2: VIDIOC_S_CROP\n");
}
}
CLEAR (capture->form);
capture->form.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
/* read the current setting, mainly to retreive the pixelformat information */
ioctl (capture->deviceHandle, VIDIOC_G_FMT, &capture->form);
/* set the values we want to change */
capture->form.fmt.pix.width = w;
capture->form.fmt.pix.height = h;
capture->form.fmt.win.chromakey = 0;
capture->form.fmt.win.field = V4L2_FIELD_ANY;
capture->form.fmt.win.clips = 0;
capture->form.fmt.win.clipcount = 0;
capture->form.fmt.pix.field = V4L2_FIELD_ANY;
/* ask the device to change the size
* don't test if the set of the size is ok, because some device
* don't allow changing the size, and we will get the real size
* later */
ioctl (capture->deviceHandle, VIDIOC_S_FMT, &capture->form);
/* try to set framerate to 30 fps */
struct v4l2_streamparm setfps;
memset (&setfps, 0, sizeof(struct v4l2_streamparm));
setfps.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
setfps.parm.capture.timeperframe.numerator = 1;
setfps.parm.capture.timeperframe.denominator = 30;
ioctl (capture->deviceHandle, VIDIOC_S_PARM, &setfps);
/* we need to re-initialize some things, like buffers, because the size has
* changed */
capture->FirstCapture = 1;
/* Get window info again, to get the real value */
if (-1 == ioctl (capture->deviceHandle, VIDIOC_G_FMT, &capture->form))
{
fprintf(stderr, "VIDEOIO ERROR: V4L/V4L2: Could not obtain specifics of capture window.\n\n");
icvCloseCAM_V4L(capture);
return 0;
}
return 0;
}
#endif /* HAVE_CAMV4L2 */
#if defined(HAVE_CAMV4L) && defined(HAVE_CAMV4L2)
else
#endif /* HAVE_CAMV4L && HAVE_CAMV4L2 */
#ifdef HAVE_CAMV4L
{
if (capture==0) return 0;
if (w>capture->capability.maxwidth) {
w=capture->capability.maxwidth;
}
if (h>capture->capability.maxheight) {
h=capture->capability.maxheight;
}
capture->captureWindow.width=w;
capture->captureWindow.height=h;
if (ioctl(capture->deviceHandle, VIDIOCSWIN, &capture->captureWindow) < 0) {
icvCloseCAM_V4L(capture);
return 0;
}
if (ioctl(capture->deviceHandle, VIDIOCGWIN, &capture->captureWindow) < 0) {
icvCloseCAM_V4L(capture);
return 0;
}
capture->FirstCapture = 1;
}
#endif /* HAVE_CAMV4L */
return 0;
}
static int icvSetControl (CvCaptureCAM_V4L* capture,
int property_id, double value) {
@ -2589,23 +2522,30 @@ static int icvSetPropertyCAM_V4L( CvCaptureCAM_V4L* capture,
/* two subsequent calls setting WIDTH and HEIGHT will change
the video size */
/* the first one will return an error, though. */
switch (property_id) {
case CV_CAP_PROP_FRAME_WIDTH:
width = cvRound(value);
if(width !=0 && height != 0) {
retval = icvSetVideoSize( capture, width, height);
capture->width = width;
capture->height = height;
retval = v4l2_reset( capture);
width = height = 0;
}
break;
case CV_CAP_PROP_FRAME_HEIGHT:
height = cvRound(value);
if(width !=0 && height != 0) {
retval = icvSetVideoSize( capture, width, height);
capture->width = width;
capture->height = height;
retval = v4l2_reset( capture);
width = height = 0;
}
break;
case CV_CAP_PROP_FPS:
capture->fps = value;
retval = v4l2_reset( capture);
break;
default:
retval = icvSetControl(capture, property_id, value);
break;

Write Preview
Loading…
Cancel
Save