[cpia] CPiA 0.7.2 & Zoomtel camera: Colour balance strangeness
rich@annexia.org
rich@annexia.org
Tue, 29 Feb 2000 21:42:03 +0000
Dear all:
Running gqcam supplied with cpia-0.7.2 (kernel 2.3.48), or
running Xawtv, I get strange colour-balance problems. The
picture appears yellow most of the time, as in this example:
http://www.annexia.org/tmp/yellow.jpg
(about 1 in every 10 times I run the program, the colour
is correct). Note that the walls in this picture are white
and the poster on the right is turquoise.
If I put my hand over the camera for a few seconds, then
afterwards, everything is green (:-)
http://www.annexia.org/tmp/green.jpg
... for a few seconds before going dark!
http://www.annexia.org/tmp/dark.jpg
... permanently. You have to restart gqcam to get back to
`normal' (ie. yellow mode).
I have tried setting color_balance_mode and exposure_mode
to manual and auto, but to no apparent effect. I also tried
setting the {red,green,blue}_gain settings, but these seem
to have a mind of their own, and just wander back to obviously
incorrect values after I set them (independent of whether the
various exposure_mode and color_balance_mode are manual or
not).
Oh, and these problems only really occur in low light conditions
(with a 60W bulb). In very bright daylight the results are much
better. Being a hacker I'm obviously mainly interested in the low
light situation :-)
Any ideas what's going on?
Rich.
read-only
-----------------------
CPIA Version: 1.30 (2.10)
CPIA PnP-ID: 0553:0002:0100
VP-Version: 1.0 0100
system_state: 0x02
grab_state: 0x10
stream_state: 0x00
fatal_error: 0x00
cmd_error: 0x00
debug_flags: 0x00
vp_status: 0x10
error_code: 0x80
video_size: CIF
sub_sample: 422
yuv_order: YUYV
roi: ( 0, 0) to (352, 288)
actual_fps: 4
transfer_rate: 918kB/s
read-write
----------------------- current min max default comment
brightness: 50 0 100 50
contrast: 48 0 96 48 steps of 8
saturation: 49 0 100 50
sensor_fps: 15.000 3 30 15
stream_start_line: 240 0 288 240
ecp_timing: normal slow normal normal
color_balance_mode: manual manual auto auto
red_gain: 6 0 212 32
green_gain: 208 0 212 6
blue_gain: 210 0 212 92
max_gain: 2 1,2,4,8 2
exposure_mode: manual manual auto auto
centre_weight: off off on on
gain: 2 1 max_gain 1 1,2,4,8 possible
fine_exp: 0 0 511 0
coarse_exp: 256 0 65535 185
red_comp: 0 220 255 220
green1_comp: 0 214 255 214
green2_comp: 192 214 255 214
blue_comp: 128 230 255 230
apcor_gain1: 0x1c 0x0 0xff 0x1c
apcor_gain2: 0x1a 0x0 0xff 0x1a
apcor_gain4: 0x2d 0x0 0xff 0x2d
apcor_gain8: 0x2a 0x0 0xff 0x2a
vl_offset_gain1: 24 0 255 24
vl_offset_gain2: 28 0 255 28
vl_offset_gain4: 30 0 255 30
vl_offset_gain8: 30 0 255 30
flicker_control: off off on off
mains_frequency: 50 50 60 50 only 50/60
allowable_overexposure: 0 0 255 0
compression_mode: auto none,auto,manual auto
decimation_enable: off off off off
compression_target: framerate framerate quality quality
target_framerate: 7 0 30 7
target_quality: 10 0 255 10
y_threshold: 3 0 31 15
uv_threshold: 3 0 31 15
hysteresis: 3 0 255 3
threshold_max: 11 0 255 11
small_step: 1 0 255 1
large_step: 3 0 255 3
decimation_hysteresis: 2 0 255 2
fr_diff_step_thresh: 5 0 255 5
q_diff_step_thresh: 3 0 255 3
decimation_thresh_mod: 2 0 255 2
--
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