Hi,
On 26.04.2017 16:23, Pavel Machek wrote:
Hi!
I don't see why it would be hard to open files or have threads inside
a library. There are several libraries that do that already, specially
the ones designed to be used on multimidia apps.
Well, This is what the libv4l2 says:
This file implements libv4l2, which offers v4l2_ prefixed versions
of
open/close/etc. The API is 100% the same as directly opening
/dev/videoX
using regular open/close/etc, the big difference is that format
conversion
but if I open additional files in v4l2_open(), API is no longer the
same, as unix open() is defined to open just one file descriptor.
Now. There is autogain support in libv4lconvert, but it expects to use
same fd for camera and for the gain... which does not work with
subdevs.
Of course, opening subdevs by name like this is not really
acceptable. But can you suggest a method that is?
There are two separate things here:
1) Autofoucs for a device that doesn't use subdev API
2) libv4l2 support for devices that require MC and subdev API
Actually there are three: 0) autogain. Unfortunately, I need autogain
first before autofocus has a chance...
And that means... bayer10 support for autogain.
Plus, I changed avg_lum to long long. Quick calculation tells me int
could overflow with few megapixel sensor.
Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
longer works.
Regards,
Pavel
diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
index c6866d6..0b52d0f 100644
--- a/lib/libv4lconvert/processing/autogain.c
+++ b/lib/libv4lconvert/processing/autogain.c
@@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
}
}
+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
+{
+ long long avg_lum = 0;
+ int x, y;
+
+ buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
+ fmt->fmt.pix.width / 4;
+
+ for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+ for (x = 0; x < fmt->fmt.pix.width / 2; x++)
That would take some time :). AIUI, we have NEON support in ARM kernels
(CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert
the above loop to NEON-optimized when it comes to it? Are there any
drawbacks in using NEON code in kernel?
+ avg_lum += *buf++;
+ buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
+ }
+ avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+ avg_lum /= 4;
+ return avg_lum;
+}
+
+static int get_luminosity_bayer8(unsigned char *buf, const struct v4l2_format *fmt)
+{
+ long long avg_lum = 0;
+ int x, y;
+
+ buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
+ fmt->fmt.pix.width / 4;
+
+ for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+ for (x = 0; x < fmt->fmt.pix.width / 2; x++)
ditto.
+ avg_lum += *buf++;
+ buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
+ }
+ avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+ return avg_lum;
+}
+
/* auto gain and exposure algorithm based on the knee algorithm described here:
http://ytse.tricolour.net/docs/LowLightOptimization.html */
static int autogain_calculate_lookup_tables(
@@ -100,17 +142,16 @@ static int autogain_calculate_lookup_tables(
switch (fmt->fmt.pix.pixelformat) {
+ case V4L2_PIX_FMT_SGBRG10:
+ case V4L2_PIX_FMT_SGRBG10:
+ case V4L2_PIX_FMT_SBGGR10:
+ case V4L2_PIX_FMT_SRGGB10:
+ avg_lum = get_luminosity_bayer10((void *) buf, fmt);
+ break;
+
case V4L2_PIX_FMT_SGBRG8:
case V4L2_PIX_FMT_SGRBG8:
case V4L2_PIX_FMT_SBGGR8:
case V4L2_PIX_FMT_SRGGB8:
- buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
- fmt->fmt.pix.width / 4;
-
- for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
- for (x = 0; x < fmt->fmt.pix.width / 2; x++)
- avg_lum += *buf++;
- buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
- }
- avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+ avg_lum = get_luminosity_bayer8(buf, fmt);
break;
case V4L2_PIX_FMT_RGB24:
diff --git a/lib/libv4lconvert/processing/libv4lprocessing.c b/lib/libv4lconvert/processing/libv4lprocessing.c
index b061f50..b98d024 100644
--- a/lib/libv4lconvert/processing/libv4lprocessing.c
+++ b/lib/libv4lconvert/processing/libv4lprocessing.c
@@ -164,6 +165,10 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
case V4L2_PIX_FMT_SGRBG8:
case V4L2_PIX_FMT_SBGGR8:
case V4L2_PIX_FMT_SRGGB8:
+ case V4L2_PIX_FMT_SGBRG10:
+ case V4L2_PIX_FMT_SGRBG10:
+ case V4L2_PIX_FMT_SBGGR10:
+ case V4L2_PIX_FMT_SRGGB10:
case V4L2_PIX_FMT_RGB24:
case V4L2_PIX_FMT_BGR24:
break;
