On Mon, Jul 13, 2020 at 07:39:41PM +0100, Laurence Tratt wrote:
> video(1) allows users to adjust controls such as brightness, saturation
> (etc.) depending on the input device in question. These values persist even
> after video(1) has quit, allowing you to e.g. increase the brightness of a
> webcam before connecting to a video call. However, the only way to adjust
> values is to hold down keys in the GUI, which is slow, error prone, and
> can't easily be scripted.
>
> This patch adds a "-c" option to video(1) which either takes the special
> value "reset" or a "control=value" pair. For example:
>
> $ video -c reset
>
> resets all the controls to their default values. Assuming the input device
> in question supports brightness one can set that as follows:
>
> $ video -c brightness=200
>
> Note that the available controls, and their min/max values, will vary from
> device to device.
>
> To keep the patch simple, only one "-c" option can be passed to video(1) at
> a time. Note that passing this option causes video(1) to quit before
> displaying video (in identical fashion to "-q") which makes it useful for
> scripting purposes.
The attached patch reworks things a bit. First, it now works with
white_balance_temperature, which (at least on my C920) requires mmap_init to
be called first. Second, the previous patch sometimes set controls to
surprising values because it called what is (in effect) a "change control by
X" function. This patch now renames the "old" function to "dev_inc_ctrl" and
introduces a new "dev_set_ctrl_abs". This then provides an obvious
opportunity to simplify the reset function.
With this patch I can do things like:
$ video -c white_balance_temperature=6500
$ video -c brightness=200
$ video && video -c reset && video
and see changes being made as appropriate.
Laurie
Index: video.1
===================================================================
RCS file: /cvs/xenocara/app/video/video.1,v
retrieving revision 1.15
diff -u -r1.15 video.1
--- video.1 17 Jul 2020 07:51:23 -0000 1.15
+++ video.1 17 Jul 2020 21:44:49 -0000
@@ -27,6 +27,7 @@
.Bk -words
.Op Fl \&gqRv
.Op Fl a Ar adaptor
+.Op Fl c Ar reset | control=value
.Op Fl e Ar encoding
.Op Fl f Ar file
.Op Fl i Ar input
@@ -81,6 +82,15 @@
adaptor to use.
The default is 0, the first adaptor reported by
.Xr X 7 .
+.It Fl c Ar reset | control=value
+Set control value (e.g. brightness) and exit. The special name
+.Ql reset
+resets all values to their default. The available controls can be found
+with
+.Fl q
+and the default values with
+.Fl c Ar reset
+.Fl v .
.It Fl e Ar encoding
Lowercase FOURCC name of video encoding to use.
Valid arguments are
Index: video.c
===================================================================
RCS file: /cvs/xenocara/app/video/video.c,v
retrieving revision 1.31
diff -u -r1.31 video.c
--- video.c 17 Jul 2020 07:51:23 -0000 1.31
+++ video.c 17 Jul 2020 21:44:49 -0000
@@ -192,7 +192,10 @@
#define M_IN_FILE 0x4
#define M_OUT_FILE 0x8
#define M_QUERY 0x10
+#define M_RESET 0x20
+#define M_SET_CTRL 0x40
int mode;
+ char *set_ctrl_str;
int verbose;
};
@@ -212,10 +215,12 @@
void dev_dump_info(struct video *);
void dev_dump_query(struct video *);
int dev_init(struct video *);
-void dev_set_ctrl(struct video *, int, int);
+void dev_inc_ctrl(struct video *, int, int);
+void dev_set_ctrl_abs(struct video *vid, int, int);
void dev_set_ctrl_auto_white_balance(struct video *, int);
void dev_reset_ctrls(struct video *);
+int parse_ctrl(struct video *, int *, int *);
int parse_size(struct video *);
int choose_size(struct video *);
int choose_enc(struct video *);
@@ -241,9 +246,9 @@
usage(void)
{
fprintf(stderr, "usage: %s [-gqRv] "
- "[-a adaptor] [-e encoding] [-f file] [-i input] [-O output]\n"
- " %*s [-o output] [-r rate] [-s size]\n", __progname,
- (int)strlen(__progname), "");
+ "[-a adaptor] [-c reset|control=value] [-e encoding] [-f file]\n"
+ " %*s [-i input] [-O output] [-o output] [-r rate] [-s
size]\n",
+ __progname, (int)strlen(__progname), "");
}
int
@@ -657,46 +662,46 @@
switch (str) {
case 'A':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_SHARPNESS, 1);
+ dev_inc_ctrl(vid, CTRL_SHARPNESS, 1);
break;
case 'a':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_SHARPNESS, -1);
+ dev_inc_ctrl(vid, CTRL_SHARPNESS, -1);
break;
case 'B':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_BRIGHTNESS, 1);
+ dev_inc_ctrl(vid, CTRL_BRIGHTNESS, 1);
break;
case 'b':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_BRIGHTNESS, -1);
+ dev_inc_ctrl(vid, CTRL_BRIGHTNESS, -1);
break;
case 'C':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_CONTRAST, 1);
+ dev_inc_ctrl(vid, CTRL_CONTRAST, 1);
break;
case 'c':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_CONTRAST, -1);
+ dev_inc_ctrl(vid, CTRL_CONTRAST, -1);
break;
case 'f':
resize_window(vid, 1);
break;
case 'G':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_GAIN, 1);
+ dev_inc_ctrl(vid, CTRL_GAIN, 1);
break;
case 'g':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_GAIN, -1);
+ dev_inc_ctrl(vid, CTRL_GAIN, -1);
break;
case 'H':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_HUE, 1);
+ dev_inc_ctrl(vid, CTRL_HUE, 1);
break;
case 'h':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_HUE, -1);
+ dev_inc_ctrl(vid, CTRL_HUE, -1);
break;
case 'O':
if (!wout && vid->verbose > 0)
@@ -710,11 +715,11 @@
break;
case 'M':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_GAMMA, 1);
+ dev_inc_ctrl(vid, CTRL_GAMMA, 1);
break;
case 'm':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_GAMMA, -1);
+ dev_inc_ctrl(vid, CTRL_GAMMA, -1);
break;
case 'p':
hold = !hold;
@@ -728,20 +733,20 @@
break;
case 'S':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_SATURATION, 1);
+ dev_inc_ctrl(vid, CTRL_SATURATION, 1);
break;
case 's':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid, CTRL_SATURATION, -1);
+ dev_inc_ctrl(vid, CTRL_SATURATION, -1);
break;
case 'W':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid,
+ dev_inc_ctrl(vid,
CTRL_WHITE_BALANCE_TEMPERATURE, 10);
break;
case 'w':
if (vid->mode & M_IN_DEV)
- dev_set_ctrl(vid,
+ dev_inc_ctrl(vid,
CTRL_WHITE_BALANCE_TEMPERATURE,
-10);
break;
default:
@@ -1010,10 +1015,9 @@
}
void
-dev_set_ctrl(struct video *vid, int ctrl, int change)
+dev_inc_ctrl(struct video *vid, int ctrl, int change)
{
struct dev *d = &vid->dev;
- struct v4l2_control control;
int val;
if (ctrl < 0 || ctrl >= CTRL_LAST) {
@@ -1025,6 +1029,25 @@
ctrls[ctrl].name, d->path);
return;
}
+ val = ctrls[ctrl].cur + ctrls[ctrl].step * change;
+ dev_set_ctrl_abs(vid, ctrl, val);
+}
+
+void
+dev_set_ctrl_abs(struct video *vid, int ctrl, int val)
+{
+ struct dev *d = &vid->dev;
+ struct v4l2_control control;
+
+ if (ctrl < 0 || ctrl >= CTRL_LAST) {
+ warnx("invalid control");
+ return;
+ }
+ if (!ctrls[ctrl].supported) {
+ warnx("control %s not supported by %s",
+ ctrls[ctrl].name, d->path);
+ return;
+ }
if (ctrl == CTRL_WHITE_BALANCE_TEMPERATURE) {
/*
* The spec requires auto-white balance to be off before
@@ -1032,7 +1055,6 @@
*/
dev_set_ctrl_auto_white_balance(vid, 0);
}
- val = ctrls[ctrl].cur + ctrls[ctrl].step * change;
if (val > ctrls[ctrl].max)
val = ctrls[ctrl].max;
else if (val < ctrls[ctrl].min)
@@ -1081,25 +1103,7 @@
for (i = 0; i < CTRL_LAST; i++) {
if (!ctrls[i].supported)
continue;
- if (i == CTRL_WHITE_BALANCE_TEMPERATURE) {
- /*
- * We might be asked to reset before the white balance
- * temperature has been adjusted, so we need to make
- * sure that auto-white balance really is off.
- */
- dev_set_ctrl_auto_white_balance(vid, 0);
- }
- control.id = ctrls[i].id;
- control.value = ctrls[i].def;
- if (ioctl(d->fd, VIDIOC_S_CTRL, &control) != 0)
- warn("VIDIOC_S_CTRL(%s)", ctrls[i].name);
- control.id = ctrls[i].id;
- if (ioctl(d->fd, VIDIOC_G_CTRL, &control) != 0)
- warn("VIDIOC_G_CTRL(%s)", ctrls[i].name);
- ctrls[i].cur = control.value;
- if (vid->verbose > 0)
- fprintf(stderr, "%s now %d\n", ctrls[i].name,
- ctrls[i].cur);
+ dev_set_ctrl_abs(vid, i, ctrls[i].def);
if (i == CTRL_WHITE_BALANCE_TEMPERATURE) {
dev_set_ctrl_auto_white_balance(vid, 1);
}
@@ -1221,6 +1225,39 @@
return 1;
}
+
+int
+parse_ctrl(struct video *vid, int *ctrl_id, int *ctrl_val)
+{
+ char *valp;
+ const char *errstr;
+
+ if (!vid->set_ctrl_str) {
+ return 0;
+ }
+
+ valp = strsep(&vid->set_ctrl_str, "=");
+ if (*valp == '\0' || vid->set_ctrl_str == '\0') {
+ return 0;
+ }
+ for (*ctrl_id = 0; *ctrl_id < CTRL_LAST; (*ctrl_id)++) {
+ if (strcmp(valp, ctrls[*ctrl_id].name) == 0) {
+ break;
+ }
+ }
+ if (*ctrl_id == CTRL_LAST) {
+ warnx("Unknown control '%s'", valp);
+ return 0;
+ }
+ *ctrl_val = strtonum(vid->set_ctrl_str, ctrls[*ctrl_id].min,
+ ctrls[*ctrl_id].max, &errstr);
+ if (errstr != NULL) {
+ warnx("control value '%s' is %s", valp, errstr);
+ return 0;
+ }
+ return 1;
+}
+
int
parse_size(struct video *vid)
{
@@ -1481,6 +1518,8 @@
int
setup(struct video *vid)
{
+ int ctrl_id, ctrl_val;
+
if (vid->mode & M_IN_FILE) {
if (!strcmp(vid->iofile, "-"))
vid->iofile_fd = STDIN_FILENO;
@@ -1520,6 +1559,7 @@
if (!parse_size(vid) || !choose_size(vid))
return 0;
+
vid->bpf = vid->width * vid->height * encs[vid->enc].bpp / NBBY;
if (vid->verbose > 0) {
@@ -1553,17 +1593,30 @@
if ((vid->mode & M_IN_DEV) && !dev_init(vid))
return 0;
+ if (vid->mmap_on) {
+ if (!mmap_init(vid))
+ return 0;
+ }
+
+ if (vid->mode & M_SET_CTRL) {
+ if (!parse_ctrl(vid, &ctrl_id, &ctrl_val)) {
+ return 0;
+ }
+ dev_set_ctrl_abs(vid, ctrl_id, ctrl_val);
+ return 1;
+ }
+
+ if (vid->mode & M_RESET) {
+ dev_reset_ctrls(vid);
+ return 1;
+ }
+
if ((vid->mode & M_OUT_XV) && !xv_init(vid))
return 0;
if (vid->sz_str && !strcmp(vid->sz_str, "full"))
resize_window(vid, 1);
- if (vid->mmap_on) {
- if (!mmap_init(vid))
- return 0;
- }
-
if (vid->mode & M_OUT_XV)
net_wm_supported(vid);
@@ -1949,7 +2002,7 @@
vid.mmap_on = 1; /* mmap method is default */
wout = 1;
- while ((ch = getopt(argc, argv, "gqRva:e:f:i:O:o:r:s:")) != -1) {
+ while ((ch = getopt(argc, argv, "gqRva:c:e:f:i:O:o:r:s:")) != -1) {
switch (ch) {
case 'a':
x->cur_adap = strtonum(optarg, 0, 4, &errstr);
@@ -1958,6 +2011,17 @@
errs++;
}
break;
+ case 'c':
+ if ((vid.mode & M_RESET) || (vid.mode & M_SET_CTRL)) {
+ warnx("Only one '-c' option allowed.");
+ errs++;
+ } else if (strcmp(optarg, "reset") == 0) {
+ vid.mode |= M_RESET;
+ } else {
+ vid.mode |= M_SET_CTRL;
+ vid.set_ctrl_str = strdup(optarg);
+ }
+ break;
case 'e':
vid.enc = find_enc(optarg);
if (vid.enc >= ENC_LAST) {
@@ -2055,6 +2119,10 @@
if (!setup(&vid))
cleanup(&vid, 1);
+
+ if ((vid.mode & M_RESET) || (vid.mode & M_SET_CTRL)) {
+ cleanup(&vid, 0);
+ }
if (vid.mode & M_IN_FILE) {
if (pledge("stdio rpath", NULL) == -1)
