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

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

On Sunday 30 May 2010 23:58:11 Andy Walls wrote:
> On Sun, 2010-05-30 at 23:28 +0200, Ondrej Zary wrote:
> > 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:
> > >
> > > 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...
>
> I would try extracting a JPEG header from one of the files captured by
> the camera in stand alone mode (either a JPEG still or MJPEG file), and
> put that header together with the image data from the USB capture.  It
> may not look perfect, but hopefully you will get something you
> recognize.

Just thought about the same thing so I uploaded a video file: 
http://www.rainbow-software.org/linux_files/spca1528/sunp0003.avi

> Attached was Theodore's first attempt of such a procedure with a header
> extracted from a standalone image file from my Jeilin based camera and
> USB snoop data from the same camera.  It wasn't perfect, but it was
> recognizable.

Thanks, I'll try that tomorrow.

> I did look at the image data file Jean-Francois provided from your
> usbsnoop logs.  To my eye the data looks like it is Huffman coded
> (indicating JPEG).  Maybe I'm just seeing what I want to see.
>
>
> Regards,
> Andy

-- 
Ondrej Zary