Re: SPCA1527A/SPCA1528 (micro)SD camera in webcam mode

[Ondrej Zary <linux@rainbow-software.org>]

On Sunday 30 May 2010 21:26:14 Andy Walls wrote:
> On Sun, 2010-05-30 at 19:55 +0200, Ondrej Zary wrote:
> > On Sunday 30 May 2010 13:34:55 Jean-Francois Moine wrote:
> > > On Sat, 29 May 2010 21:32:07 +0200
> > >
> > > Ondrej Zary <linux@rainbow-software.org> wrote:
> > > > The Color Space/Compression reported by the driver is only one: RGB
> > > > 24 The driver also uses these files which may (or may not) be related
> > > > to used compression: iyuv_32.dll, msh263.drv, msyuv.dll, tsbyuv.dll
> > > > In standalone mode, the camera records video in MJPEG format.
> > >
> > > Hello Ondrej,
> > >
> > > Bad news, the images are compressed by an unknown algorithm (unknown
> > > from Linux point of vue). The decompression function could be found in
> > > some part of the ms-win driver, but:
> > > - first, I have no time to search and disassemble this function,
> > > - then, I did have this problem with an other webcam (17a1:0118), and
> > >   after searching for a long time, nobody could find the function, and
> > >   the driver is in stand-by since 2 years,
> > > - eventually, is this legal?
> >
> > That's bad...
> >
> > The driver contains file sp5x_32.dll which is registered in system.ini
> > file as [drivers32]
> > VIDC.SP54=SP5X_32.DLL
> >
> > Seems that the codec is called SP54 - hope that it's used to decompress
> > the data.
> >
> > > All I can do is to code the driver and let you or anyone find the
> > > decompression function...
>
> SP54 is Sunplus' ( http://www.sunplus.com.tw/ ) FourCC code for a
> version of MJPEG with the headers removed according to
>
> 	http://www.fourcc.org/
>
> > Maybe we can dump some data, create AVI file from that and try to decode
> > the file using that codec.
>
> FourCC.org points to this page:
>
> 	http://libland.fr.st/download.html
>
> which points to a utility to conver the data back into an MJPEG:
>
> 	http://mxhaard.free.fr/spca50x/Download/sp54convert.tar.gz
>
>
> I have no idea if any of the above is true, 'cause I read it on the
> Internet. ;)

Modified that utility to work on raw video frame extracted from usbsnoop file. 
The bad news is that the resulting jpeg file is not readable.

I also deleted the sp5x_32.dll file and the camera still works...

-- 
Ondrej Zary