Re: RFC on proposed patches to mr97310a.c for gspca and v4l

[Thomas Kaiser <v4l@kaiser-linux.li>]

Hello Theodore

kilgota@banach.math.auburn.edu wrote:
> Also, after the byte indicator for the compression algorithm there are 
> some more bytes, and these almost definitely contain information which 
> could be valuable while doing image processing on the output. If they 
> are already kept and passed out of the module over to libv4lconvert, 
> then it would be very easy to do something with those bytes if it is 
> ever figured out precisely what they mean. But if it is not done now it 
> would have to be done then and would cause even more trouble.

I sent it already in private mail to you. Here is the observation I made 
for the PAC207 SOF some years ago:

 From usb snoop.
FF FF 00 FF 96 64 xx 00 xx xx xx xx xx xx 00 00
1. xx: looks like random value
2. xx: changed from 0x03 to 0x0b
3. xx: changed from 0x06 to 0x49
4. xx: changed from 0x07 to 0x55
5. xx: static 0x96
6. xx: static 0x80
7. xx: static 0xa0

And I did play in Linux and could identify some fields :-) .
In Linux the header looks like this:

FF FF 00 FF 96 64 xx 00 xx xx xx xx xx xx F0 00
1. xx: don't know but value is changing between 0x00 to 0x07
2. xx: this is the actual pixel clock
3. xx: this is changing according light conditions from 0x03 (dark) to
0xfc (bright) (center)
4. xx: this is changing according light conditions from 0x03 (dark) to
0xfc (bright) (edge)
5. xx: set value "Digital Gain of Red"
6. xx: set value "Digital Gain of Green"
7. xx: set value "Digital Gain of Blue"

Thomas