Re: libv4l release: 0.5.97: the whitebalance release!

[Hans de Goede <hdegoede@redhat.com>]

On 04/18/2009 04:40 PM, Erik Andrén wrote:
>
> Hans de Goede wrote:
>>
>> On 04/17/2009 09:27 PM, Erik Andrén wrote:
>>> Hans de Goede wrote:
>>>> On 04/16/2009 10:46 PM, Adam Baker wrote:
>>>>> On Thursday 16 Apr 2009, Hans de Goede wrote:
>>>>>> On 04/16/2009 12:26 AM, Adam Baker wrote:
>>>>>>> On Wednesday 15 Apr 2009, Hans de Goede wrote:
>>>>>>>> Currently only whitebalancing is enabled and only on Pixarts (pac)
>>>>>>>> webcams (which benefit tremendously from this). To test this with
>>>>>>>> other
>>>>>>>> webcams (after instaling this release) do:
>>>>>>>>
>>>>>>>> export LIBV4LCONTROL_CONTROLS=15
>>>>>>>> LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so v4l2ucp&
>>>>>>> Strangely while those instructions give me a whitebalance control
>>>>>>> for the
>>>>>>> sq905 based camera I can't get it to appear for a pac207 based camera
>>>>>>> regardless of whether LIBV4LCONTROL_CONTROLS is set.
>>>>>> Thats weird, there is a small bug in the handling of pac207
>>>>>> cams with usb id 093a:2476 causing libv4l to not automatically
>>>>>> enable whitebalancing (and the control) for cams with that id,
>>>>>> but if you have LIBV4LCONTROL_CONTROLS set (exported!) both
>>>>>> when loading v4l2ucp (you must preload v4l2convert.so!) and
>>>>>> when loading your viewer, then it should work.
>>>>>>
>>>>> I've tested it by plugging in the sq905 camera, verifying the
>>>>> whitebablance
>>>>> control is present and working, unplugging the sq905 and plugging in
>>>>> the
>>>>> pac207 and using up arrow to restart v4l2ucp and svv so I think I've
>>>>> eliminated most finger trouble possibilities. The pac207 is id
>>>>> 093a:2460 so
>>>>> not the problem id. I'll have to investigate more thoroughly later.
>>>>>
>>>> Does the pac207 perhaps have a / in its "card" string (see v4l-info
>>>> output) ?
>>>> if so try out this patch:
>>>> http://linuxtv.org/hg/~hgoede/libv4l/rev/1e08d865690a
>>>>
>>> I have the same issue as Adam when trying to test this with my
>>> gspca_stv06xx based Quickcam Web camera i. e no whitebalancing
>>> controls show up. I'm attaching a dump which logs all available
>>> pixformats and v4l2ctrls showing that libv4l is properly loaded.
>>> (And yes, LIBV4LCONTROL_CONTROLS is exported and set to 15).
>>>
>>> Best regards,
>>> Erik
>>>
>> Ah, you are using v4l2-ctl, not v4l2ucp, and that uses
>> V4L2_CTRL_FLAG_NEXT_CTRL
>> control enumeration. My code doesn't handle V4L2_CTRL_FLAG_NEXT_CTRL
>> (which is
>> a bug). I'm not sure when I'll have time to fix this. Patches welcome,
>> or in
>> the mean time use v4l2ucp to play with the controls.
>>
>
> Actually, I've tried to use both without finding the controls.
> I've only tried with v4l2ucp v. 1.2. Is 1.3 necessary?
>

Apparently there are different versions of v4l2ucp in different distro's
and some do use the V4L2_CTRL_FLAG_NEXT_CTRL, just like v4l2-ctl. See
Adam Baker's patch later in this thread. Which I will apply to my
tree after I've reviewed it (when I find some time currently I've a lot of
$work$ )

Regards,

Hans