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Diffstat (limited to 'drivers/media/video/gspca/coarse_expo_autogain.h')
-rw-r--r--drivers/media/video/gspca/coarse_expo_autogain.h116
1 files changed, 0 insertions, 116 deletions
diff --git a/drivers/media/video/gspca/coarse_expo_autogain.h b/drivers/media/video/gspca/coarse_expo_autogain.h
deleted file mode 100644
index 1cb9d941eaf6..000000000000
--- a/drivers/media/video/gspca/coarse_expo_autogain.h
+++ /dev/null
@@ -1,116 +0,0 @@
-/*
- * Auto gain algorithm for camera's with a coarse exposure control
- *
- * Copyright (C) 2010 Hans de Goede <hdegoede@redhat.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-/* Autogain + exposure algorithm for cameras with a coarse exposure control
- (usually this means we can only control the clockdiv to change exposure)
- As changing the clockdiv so that the fps drops from 30 to 15 fps for
- example, will lead to a huge exposure change (it effectively doubles),
- this algorithm normally tries to only adjust the gain (between 40 and
- 80 %) and if that does not help, only then changes exposure. This leads
- to a much more stable image then using the knee algorithm which at
- certain points of the knee graph will only try to adjust exposure,
- which leads to oscilating as one exposure step is huge.
-
- Note this assumes that the sd struct for the cam in question has
- exp_too_high_cnt and exp_too_high_cnt int members for use by this function.
-
- Returns 0 if no changes were made, 1 if the gain and or exposure settings
- where changed. */
-static int gspca_coarse_grained_expo_autogain(struct gspca_dev *gspca_dev,
- int avg_lum, int desired_avg_lum, int deadzone)
-{
- int i, steps, gain, orig_gain, exposure, orig_exposure;
- int gain_low, gain_high;
- const struct ctrl *gain_ctrl = NULL;
- const struct ctrl *exposure_ctrl = NULL;
- struct sd *sd = (struct sd *) gspca_dev;
- int retval = 0;
-
- for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
- if (gspca_dev->ctrl_dis & (1 << i))
- continue;
- if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
- gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
- if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
- exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
- }
- if (!gain_ctrl || !exposure_ctrl) {
- PDEBUG(D_ERR, "Error: gspca_coarse_grained_expo_autogain "
- "called on cam without gain or exposure");
- return 0;
- }
-
- if (gain_ctrl->get(gspca_dev, &gain) ||
- exposure_ctrl->get(gspca_dev, &exposure))
- return 0;
-
- orig_gain = gain;
- orig_exposure = exposure;
- gain_low =
- (gain_ctrl->qctrl.maximum - gain_ctrl->qctrl.minimum) / 5 * 2;
- gain_low += gain_ctrl->qctrl.minimum;
- gain_high =
- (gain_ctrl->qctrl.maximum - gain_ctrl->qctrl.minimum) / 5 * 4;
- gain_high += gain_ctrl->qctrl.minimum;
-
- /* If we are of a multiple of deadzone, do multiple steps to reach the
- desired lumination fast (with the risc of a slight overshoot) */
- steps = (desired_avg_lum - avg_lum) / deadzone;
-
- PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d",
- avg_lum, desired_avg_lum, steps);
-
- if ((gain + steps) > gain_high &&
- sd->exposure < exposure_ctrl->qctrl.maximum) {
- gain = gain_high;
- sd->exp_too_low_cnt++;
- } else if ((gain + steps) < gain_low &&
- sd->exposure > exposure_ctrl->qctrl.minimum) {
- gain = gain_low;
- sd->exp_too_high_cnt++;
- } else {
- gain += steps;
- if (gain > gain_ctrl->qctrl.maximum)
- gain = gain_ctrl->qctrl.maximum;
- else if (gain < gain_ctrl->qctrl.minimum)
- gain = gain_ctrl->qctrl.minimum;
- sd->exp_too_high_cnt = 0;
- sd->exp_too_low_cnt = 0;
- }
-
- if (sd->exp_too_high_cnt > 3) {
- exposure--;
- sd->exp_too_high_cnt = 0;
- } else if (sd->exp_too_low_cnt > 3) {
- exposure++;
- sd->exp_too_low_cnt = 0;
- }
-
- if (gain != orig_gain) {
- gain_ctrl->set(gspca_dev, gain);
- retval = 1;
- }
- if (exposure != orig_exposure) {
- exposure_ctrl->set(gspca_dev, exposure);
- retval = 1;
- }
-
- return retval;
-}