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Sensor orientation reporting

PATCH In review Adam Baker 6 participants 10 messages Mar 29, 2009 – Apr 10, 2009 Media (V4L/DVB)

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Adam Baker

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#0 lore raw

v2 cover Sensor orientation reporting

Hi,

Based on the limited feedback from last time I'm assuming people are generally happy with this so I've updated according to Jean-Francois Moine's comments and added documentation. Again this features only the minimum changes in libv4l to make some use of the info.

author
#1 lore raw

Add support to the SQ-905 driver to pass back to user space the sensor orientation information obtained from the camera during init. Modifies gspca and the videodev2.h header to create the necessary API.

---

linux/drivers/media/video/gspca/gspca.c +1 -0
diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.c
@@ -1147,6 +1147,7 @@
 	if (input->index != 0)
 		return -EINVAL;
 	input->type = V4L2_INPUT_TYPE_CAMERA;
+	input->status = gspca_dev->cam.input_flags;
 	strncpy(input->name, gspca_dev->sd_desc->name,
 		sizeof input->name);
 	return 0;
linux/drivers/media/video/gspca/gspca.h +1 -0
diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.h
@@ -56,6 +56,7 @@
 				 * - cannot be > MAX_NURBS
 				 * - when 0 and bulk_size != 0 means
 				 *   1 URB and submit done by subdriver */
+	u32 input_flags;	/* value for ENUM_INPUT status flags */
 };
 
 struct gspca_dev;
linux/drivers/media/video/gspca/sq905.c +6 -0
diff -r d8d701594f71 linux/drivers/media/video/gspca/sq905.c
@@ -360,6 +360,12 @@
 	gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
 	if (!(ident & SQ905_HIRES_MASK))
 		gspca_dev->cam.nmodes--;
+
+	if (ident & SQ905_ORIENTATION_MASK)
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
+	else
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
+					     V4L2_IN_ST_HFLIP;
 	return 0;
 }
 
linux/include/linux/videodev2.h +3 -0
diff -r d8d701594f71 linux/include/linux/videodev2.h
@@ -737,6 +737,11 @@
 #define V4L2_IN_ST_NO_SIGNAL   0x00000002
 #define V4L2_IN_ST_NO_COLOR    0x00000004
 
+/* field 'status' - sensor orientation */
+/* If sensor is mounted upside down set both bits */
+#define V4L2_IN_ST_HFLIP       0x00000010 /* Output is flipped horizontally 

*/
+#define V4L2_IN_ST_VFLIP 0x00000020 /* Output is flipped vertically */
+
/* field 'status' - analog */

 #define V4L2_IN_ST_NO_H_LOCK   0x00000100  /* No horizontal sync lock */
 #define V4L2_IN_ST_COLOR_KILL  0x00000200  /* Color killer is active */
author
#2 lore raw

PATCH v2 2/4 Specify SHELL in documentation Makefile

The Makefile for the V4L2 spec uses bash extensions but was using the default system shell, change it to explicitly request bash.

---

v4l2-spec/Makefile +1 -0
diff -r d8d701594f71 v4l2-spec/Makefile
@@ -1,5 +1,6 @@
 # Also update in v4l2.sgml!
 VERSION = 0.25
+SHELL=/bin/bash
 
 SGMLS = \
 	biblio.sgml \
author
#3 lore raw

PATCH v2 3/4 Document the orientation flags in ENUMINPUT

Add documentation for the flags that have been added to VIDIOC_ENUMINPUT to specify the sensor orientation.

---

v4l2-spec/vidioc-enuminput.sgml +18 -1
diff -r d8d701594f71 v4l2-spec/vidioc-enuminput.sgml
@@ -119,7 +119,7 @@
 	    <entry><structfield>status</structfield></entry>
 	    <entry>This field provides status information about the
 input. See <xref linkend="input-status"> for flags.
-<structfield>status</structfield> is only valid when this is the
+With the exception of the sensor orientation bits <structfield>status</structfield> is only valid when this is the
 current input.</entry>
 	  </row>
 	  <row>
@@ -188,6 +188,23 @@
 detect color modulation in the signal.</entry>
 	  </row>
 	  <row>
+	    <entry spanname="hspan">Sensor Orientation</entry>
+	  </row>
+	  <row>
+	    <entry><constant>V4L2_IN_ST_HFLIP</constant></entry>
+	    <entry>0x00000010</entry>
+	    <entry>The input is connected to a device that produces a signal
+that is flipped horizontally and does not correct this before passing the
+signal to userspace.</entry>
+	  </row>
+	  <row>
+	    <entry><constant>V4L2_IN_ST_VFLIP</constant></entry>
+	    <entry>0x00000020</entry>
+	    <entry>The input is connected to a device that produces a signal
+that is flipped vertically and does not correct this before passing the
+signal to userspace. Note that a 180 degree rotation is the same as HFLIP | VFLIP</entry>
+	  </row>
+	  <row>
 	    <entry spanname="hspan">Analog Video</entry>
 	  </row>
 	  <row>
author
#4 lore raw

PATCH v2 4/4 Add support to libv4l to use orientation from VIDIOC_ENUMINPUT

Add check to libv4l of the sensor orientation as reported by VIDIOC_ENUMINPUT

---

v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c +13 -0
diff -r a647c2dfa989 v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c
@@ -29,6 +29,11 @@
 #define MIN(a,b) (((a)<(b))?(a):(b))
 #define ARRAY_SIZE(x) ((int)sizeof(x)/(int)sizeof((x)[0]))
 
+/* Workaround this potentially being missing from videodev2.h */
+#ifndef V4L2_IN_ST_VFLIP
+#define V4L2_IN_ST_VFLIP       0x00000020 /* Output is flipped vertically */
+#endif
+
 /* Note for proper functioning of v4lconvert_enum_fmt the first entries in
   supported_src_pixfmts must match with the entries in supported_dst_pixfmts */
 #define SUPPORTED_DST_PIXFMTS \
@@ -134,6 +139,7 @@
   int i, j;
   struct v4lconvert_data *data = calloc(1, sizeof(struct v4lconvert_data));
   struct v4l2_capability cap;
+  struct v4l2_input input;
 
   if (!data)
     return NULL;
@@ -161,6 +167,13 @@
 
   /* Check if this cam has any special flags */
   data->flags = v4lconvert_get_flags(data->fd);
+  if ((syscall(SYS_ioctl, fd, VIDIOC_G_INPUT, &input.index) == 0) &&
+      (syscall(SYS_ioctl, fd, VIDIOC_ENUMINPUT, &input) == 0)) {
+    /* Don't yet support independent HFLIP and VFLIP so getting
+     * image the right way up is highest priority. */
+    if (input.status & V4L2_IN_ST_VFLIP)
+      data->flags |= V4LCONVERT_ROTATE_180;
+  }
   if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP, &cap) == 0) {
     if (!strcmp((char *)cap.driver, "uvcvideo"))
       data->flags |= V4LCONVERT_IS_UVC;
#8 lore raw
In reply to Adam Baker
Quoted 59 lines · On Monday 30 March 2009 00:17:10 Adam Baker wrote:

Add support to the SQ-905 driver to pass back to user space the sensor orientation information obtained from the camera during init. Modifies gspca and the videodev2.h header to create the necessary API.

---
diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.c
--- a/linux/drivers/media/video/gspca/gspca.c Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/gspca.c Sun Mar 29 23:00:08
2009 +0100 @@ -1147,6 +1147,7 @@

linux/drivers/media/video/gspca/gspca.c +1 -0
 	if (input->index != 0)
 		return -EINVAL;
 	input->type = V4L2_INPUT_TYPE_CAMERA;
+	input->status = gspca_dev->cam.input_flags;
 	strncpy(input->name, gspca_dev->sd_desc->name,
 		sizeof input->name);
 	return 0;

diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.h
--- a/linux/drivers/media/video/gspca/gspca.h Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/gspca.h Sun Mar 29 23:00:08
2009 +0100 @@ -56,6 +56,7 @@

linux/drivers/media/video/gspca/gspca.h +1 -0
 				 * - cannot be > MAX_NURBS
 				 * - when 0 and bulk_size != 0 means
 				 *   1 URB and submit done by subdriver */
+	u32 input_flags;	/* value for ENUM_INPUT status flags */
 };
 
 struct gspca_dev;

diff -r d8d701594f71 linux/drivers/media/video/gspca/sq905.c
--- a/linux/drivers/media/video/gspca/sq905.c Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/sq905.c Sun Mar 29 23:00:08
2009 +0100 @@ -360,6 +360,12 @@

linux/drivers/media/video/gspca/sq905.c +6 -0
 	gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
 	if (!(ident & SQ905_HIRES_MASK))
 		gspca_dev->cam.nmodes--;
+
+	if (ident & SQ905_ORIENTATION_MASK)
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
+	else
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
+					     V4L2_IN_ST_HFLIP;
 	return 0;
 }

diff -r d8d701594f71 linux/include/linux/videodev2.h

linux/include/linux/videodev2.h +3 -0
@@ -737,6 +737,11 @@
 #define V4L2_IN_ST_NO_SIGNAL   0x00000002
 #define V4L2_IN_ST_NO_COLOR    0x00000004
 
+/* field 'status' - sensor orientation */
+/* If sensor is mounted upside down set both bits */
+#define V4L2_IN_ST_HFLIP       0x00000010 /* Output is flipped

horizontally */
+#define V4L2_IN_ST_VFLIP 0x00000020 /* Output is flipped
vertically */ +
/* field 'status' - analog */

Quoted 2 lines
 #define V4L2_IN_ST_NO_H_LOCK   0x00000100  /* No horizontal sync lock */
 #define V4L2_IN_ST_COLOR_KILL  0x00000200  /* Color killer is active */

Hi Adam,

I've only one small comment: the V4L2_IN_ST_H/VFLIP comments talk about 'Output' while these flags deal with an input. I know you mean the output from the sensor, but the point of view in this API is the application, and for the application it is an input.

Other than that I'm happy with it.

Regards,

Hans

Signature · 1 line
Hans Verkuil - video4linux developer - sponsored by TANDBERG
#9 lore raw
Quoted 70 lines · Hans Verkuil
Quoted 59 lines · On Monday 30 March 2009 00:17:10 Adam Baker wrote:

Add support to the SQ-905 driver to pass back to user space the sensor orientation information obtained from the camera during init. Modifies gspca and the videodev2.h header to create the necessary API.

---
diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.c
--- a/linux/drivers/media/video/gspca/gspca.c Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/gspca.c Sun Mar 29 23:00:08
2009 +0100 @@ -1147,6 +1147,7 @@

linux/drivers/media/video/gspca/gspca.c +1 -0
 	if (input->index != 0)
 		return -EINVAL;
 	input->type = V4L2_INPUT_TYPE_CAMERA;
+	input->status = gspca_dev->cam.input_flags;
 	strncpy(input->name, gspca_dev->sd_desc->name,
 		sizeof input->name);
 	return 0;

diff -r d8d701594f71 linux/drivers/media/video/gspca/gspca.h
--- a/linux/drivers/media/video/gspca/gspca.h Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/gspca.h Sun Mar 29 23:00:08
2009 +0100 @@ -56,6 +56,7 @@

linux/drivers/media/video/gspca/gspca.h +1 -0
 				 * - cannot be > MAX_NURBS
 				 * - when 0 and bulk_size != 0 means
 				 *   1 URB and submit done by subdriver */
+	u32 input_flags;	/* value for ENUM_INPUT status flags */
 };
 
 struct gspca_dev;

diff -r d8d701594f71 linux/drivers/media/video/gspca/sq905.c
--- a/linux/drivers/media/video/gspca/sq905.c Sun Mar 29 08:45:36 2009
+0200 +++ b/linux/drivers/media/video/gspca/sq905.c Sun Mar 29 23:00:08
2009 +0100 @@ -360,6 +360,12 @@

linux/drivers/media/video/gspca/sq905.c +6 -0
 	gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
 	if (!(ident & SQ905_HIRES_MASK))
 		gspca_dev->cam.nmodes--;
+
+	if (ident & SQ905_ORIENTATION_MASK)
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
+	else
+		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
+					     V4L2_IN_ST_HFLIP;
 	return 0;
 }

diff -r d8d701594f71 linux/include/linux/videodev2.h

linux/include/linux/videodev2.h +3 -0
@@ -737,6 +737,11 @@
 #define V4L2_IN_ST_NO_SIGNAL   0x00000002
 #define V4L2_IN_ST_NO_COLOR    0x00000004
 
+/* field 'status' - sensor orientation */
+/* If sensor is mounted upside down set both bits */
+#define V4L2_IN_ST_HFLIP       0x00000010 /* Output is flipped

horizontally */
+#define V4L2_IN_ST_VFLIP 0x00000020 /* Output is flipped
vertically */ +
/* field 'status' - analog */

Quoted 2 lines
 #define V4L2_IN_ST_NO_H_LOCK   0x00000100  /* No horizontal sync lock */
 #define V4L2_IN_ST_COLOR_KILL  0x00000200  /* Color killer is active */

Hi Adam,

I've only one small comment: the V4L2_IN_ST_H/VFLIP comments talk about 'Output' while these flags deal with an input. I know you mean the output from the sensor, but the point of view in this API is the application, and for the application it is an input.

Quoted 5 lines

Other than that I'm happy with it.

Regards,

Hans

Hmmm. These two comments?

Quoted 4 lines
Quoted 4 lines

+#define V4L2_IN_ST_HFLIP 0x00000010 /* Output is flipped
horizontally */
+#define V4L2_IN_ST_VFLIP 0x00000020 /* Output is flipped
vertically */ +

Perhaps one could change them to say /* Frames must be flipped ...

instead.

Theodore Kilgore

#5 lore raw

Re: [PATCH v2 4/4] Add support to libv4l to use orientation from VIDIOC_ENUMINPUT

In reply to Adam Baker
Quoted 5 lines · Adam Baker

Add check to libv4l of the sensor orientation as reported by VIDIOC_ENUMINPUT

Looks good, thanks. I'll apply this to my libv4l tree, as soon as its certain that the matching kernel changes will go in to the kernel without any API changes.

Thanks & Regards,

Hans

Quoted 40 lines

---
diff -r a647c2dfa989 v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c

v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c +13 -0
@@ -29,6 +29,11 @@
  #define MIN(a,b) (((a)<(b))?(a):(b))
  #define ARRAY_SIZE(x) ((int)sizeof(x)/(int)sizeof((x)[0]))
 
+/* Workaround this potentially being missing from videodev2.h */
+#ifndef V4L2_IN_ST_VFLIP
+#define V4L2_IN_ST_VFLIP       0x00000020 /* Output is flipped vertically */
+#endif
+
  /* Note for proper functioning of v4lconvert_enum_fmt the first entries in
    supported_src_pixfmts must match with the entries in supported_dst_pixfmts */
  #define SUPPORTED_DST_PIXFMTS \
@@ -134,6 +139,7 @@
    int i, j;
    struct v4lconvert_data *data = calloc(1, sizeof(struct v4lconvert_data));
    struct v4l2_capability cap;
+  struct v4l2_input input;
 
    if (!data)
      return NULL;
@@ -161,6 +167,13 @@
 
    /* Check if this cam has any special flags */
    data->flags = v4lconvert_get_flags(data->fd);
+  if ((syscall(SYS_ioctl, fd, VIDIOC_G_INPUT,&input.index) == 0)&&
+      (syscall(SYS_ioctl, fd, VIDIOC_ENUMINPUT,&input) == 0)) {
+    /* Don't yet support independent HFLIP and VFLIP so getting
+     * image the right way up is highest priority. */
+    if (input.status&  V4L2_IN_ST_VFLIP)
+      data->flags |= V4LCONVERT_ROTATE_180;
+  }
    if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP,&cap) == 0) {
      if (!strcmp((char *)cap.driver, "uvcvideo"))
        data->flags |= V4LCONVERT_IS_UVC;
#6 lore raw

Re: [PATCH v2 4/4] Add support to libv4l to use orientation from VIDIOC_ENUMINPUT

Quoted 10 lines · On Mon, 30 Mar 2009 10:30:22 +0200 Hans de Goede <[email protected]> wrote:
Quoted 5 lines · Adam Baker

Add check to libv4l of the sensor orientation as reported by VIDIOC_ENUMINPUT

Looks good, thanks. I'll apply this to my libv4l tree, as soon as its certain that the matching kernel changes will go in to the kernel without any API changes.

kernel patches merged. As per your request, I'm letting the libv4l one for you to take care.

Cheers,
Mauro

#7 lore raw

Re: [PATCH v2 4/4] Add support to libv4l to use orientation from VIDIOC_ENUMINPUT

In reply to Adam Baker

Thanks,

I've applied this to my tree, it will be part of the next libv4l release.

Regards,

Hans

Quoted 45 lines · Adam Baker

Add check to libv4l of the sensor orientation as reported by VIDIOC_ENUMINPUT

---
diff -r a647c2dfa989 v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c

v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c +13 -0
@@ -29,6 +29,11 @@
  #define MIN(a,b) (((a)<(b))?(a):(b))
  #define ARRAY_SIZE(x) ((int)sizeof(x)/(int)sizeof((x)[0]))
 
+/* Workaround this potentially being missing from videodev2.h */
+#ifndef V4L2_IN_ST_VFLIP
+#define V4L2_IN_ST_VFLIP       0x00000020 /* Output is flipped vertically */
+#endif
+
  /* Note for proper functioning of v4lconvert_enum_fmt the first entries in
    supported_src_pixfmts must match with the entries in supported_dst_pixfmts */
  #define SUPPORTED_DST_PIXFMTS \
@@ -134,6 +139,7 @@
    int i, j;
    struct v4lconvert_data *data = calloc(1, sizeof(struct v4lconvert_data));
    struct v4l2_capability cap;
+  struct v4l2_input input;
 
    if (!data)
      return NULL;
@@ -161,6 +167,13 @@
 
    /* Check if this cam has any special flags */
    data->flags = v4lconvert_get_flags(data->fd);
+  if ((syscall(SYS_ioctl, fd, VIDIOC_G_INPUT,&input.index) == 0)&&
+      (syscall(SYS_ioctl, fd, VIDIOC_ENUMINPUT,&input) == 0)) {
+    /* Don't yet support independent HFLIP and VFLIP so getting
+     * image the right way up is highest priority. */
+    if (input.status&  V4L2_IN_ST_VFLIP)
+      data->flags |= V4LCONVERT_ROTATE_180;
+  }
    if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP,&cap) == 0) {
      if (!strcmp((char *)cap.driver, "uvcvideo"))
        data->flags |= V4LCONVERT_IS_UVC;