From 556522f647ac3a60b0e74681168adb6c191dd9e0 Mon Sep 17 00:00:00 2001
From: tth <sigfood@dinorama.fr>
Date: Wed, 14 Aug 2019 19:29:11 +0200
Subject: [PATCH] period time now in floating point

---
 v4l2/grabvidseq.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/v4l2/grabvidseq.c b/v4l2/grabvidseq.c
index 31aef141..14ba0983 100644
--- a/v4l2/grabvidseq.c
+++ b/v4l2/grabvidseq.c
@@ -91,15 +91,15 @@ struct timeval                  tv;
 int                             r, fd = -1;
 unsigned int                    i, n_buffers;
 char                            *dev_name = "/dev/video0";
-char                            out_name[256];
+
 FILE                            *fout;
 struct buffer                   *buffers;
 
 int		foo, bar;
-int		period = 10;		/* delai entre les captures */
+double		period = 10.0;		/* delai entre les captures */
 int		nbre_capt = 1;		/* nombre de captures */
 int		opt;
-double		t_debut, t_final;
+double		t_final;
 char		*dest_dir = ".";	/* no trailing slash */
 char		*outfile = "out.pnm";
 
@@ -114,13 +114,14 @@ while ((opt = getopt(argc, argv, "d:hn:o:O:p:v")) != -1) {
 		case 'n':	nbre_capt = atoi(optarg);	break;
 		case 'O':	dest_dir = optarg;		break;
 		case 'o':	outfile = optarg;		break;
-		case 'p':	period = atoi(optarg);		break;
+		case 'p':	period = 1e6*atof(optarg);	break;
 		case 'v':	verbosity++;			break;
 		}
 	}
 
 if (verbosity) {
 	fprintf(stderr, "running %s  pid=%d\n", argv[0], getpid());
+	fprintf(stderr, "period is %.3f microseconds\n", period);
 	}
 
 fd = v4l2_open(dev_name, O_RDWR | O_NONBLOCK, 0);
@@ -172,7 +173,7 @@ for (n_buffers = 0; n_buffers < req.count; ++n_buffers) {
 		}
 	}
 
-t_debut = fimg_timer_set(0);
+(void)fimg_timer_set(0);
 
 for (i = 0; i < n_buffers; ++i) {
 	CLEAR(buf);
@@ -218,6 +219,11 @@ for (i = 0; i < nbre_capt; i++) {
 		return errno;
 		}
 
+	if(verbosity > 1) {
+		printf("%6d   %5.3f\n", i, fimg_timer_get(0));
+		}
+
+
 	CLEAR(buf);
 	buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	buf.memory = V4L2_MEMORY_MMAP;
@@ -253,8 +259,8 @@ for (i = 0; i < nbre_capt; i++) {
 			out_name);
 #endif
 
-	if (nbre_capt > 1 && period) {
-		sleep(period);
+	if (nbre_capt > 1 && period > 1.0) {
+		usleep(period);
 		}
 
 	xioctl(fd, VIDIOC_QBUF, &buf);