with the log I did and Daniel’s log/source, I succeeded in having a 640×480 color image. It is also Bayer.
Quite amazingly, the first image produced by the cam is a 640×480 view of what is the bottom left quarter of the normal image, sometimes the next image is normal apart to be vertically flipped and the next ones are normal.

@dsd : I made a C program to map the USBsnif log to a shorter log and a C code with some anotation. It can help to understand a log. I’ll send you the source code and a “copy_to_files” version for my webcam model. Today I
tried to understand the syntek driver to integrate my work in however it seems to me quite difficult and the USB is differently managed…
USBsniff and USBsnoop seems to be the same program, they’re was just on link to donwload it.
Affichageb.exe comes from this link : http://www.cppfrance.com/codes/EXPLOITER-WEBCAM_24541.aspx .
I forced the application to quit after it has connected the webcam.

greets
simon

static void unbayer2RGB (unsigned char *bayer, unsigned char *RGB) {
int x,y,z;

for (z = 0,y = 0; y < IMG_HEIGHT; y+=2){
for (x=0; x < IMG_WIDTH; x+=2,z+=3){
RGB[z] = bayer[x+1]; //Rot
RGB[z+1] = ((bayer[x]+bayer[x+1+IMG_WIDTH])/2); //Grün
RGB[z+2] = bayer[x+IMG_WIDTH]; //Blau
}}
}

but the resulting picture is only half as with and half as height that could be better with an other interpolation algorithm…
perhaps first of all you test it, i don’t know if you can output RGBs, or do you need YUY2?

greets
Sur3

I added a sample image (rendered as greyscale) to the git repo if you want to play with the kind of data that I get…

static void grey2realyuv (unsigned char *grey, unsigned char *YUV, int num) {
int i, j;
int y0, y1, u0, u1, v0, v1;
int gval;

for (i = 0, j = 0; i < num; i += 1, j += 4)
{
//gval = grey[i];
//GREY2YUV (gval, y0, u0 , v0);
//gval = grey[i + 1];
//GREY2YUV (gval, y1, u1 , v1);
YUV[i] = grey[i];
YUV[i + 1] = 0;
YUV[i + 2] = 0;
//YUV[j + 3] = (v0+v1)/2;
}
}

static void display_frame(void)
{
unsigned char rowbuf[IMG_WIDTH];
int i;

if (adaptor < 0)
return;

for (i = 0; i < IMG_HEIGHT / 2; i++) {
int offset = i * IMG_WIDTH;
int swap_offset = IMG_SIZE - (IMG_WIDTH * (i + 1));

/* copy top row into buffer */
// memcpy(rowbuf, imgbuf + offset, IMG_WIDTH);

/* copy lower row over upper row */
// memcpy(imgbuf + offset, imgbuf + swap_offset, IMG_WIDTH);

/* copy buffer over lower row */
// memcpy(imgbuf + swap_offset, rowbuf, IMG_WIDTH);
}

//grey2yuy2(imgbuf, framebuffer, IMG_SIZE);
grey2realyuv(imgbuf, framebuffer, IMG_SIZE);

xv_image = XvCreateImage(display, info[adaptor].base_id, FORMAT,
framebuffer, IMG_WIDTH, IMG_HEIGHT);
XvPutImage(display, info[adaptor].base_id, window, gc, xv_image,
0, 0, IMG_WIDTH, IMG_HEIGHT, 0, 0, IMG_WIDTH, IMG_HEIGHT);
XFlush(display);
}

@dsd:
I’m right, I only see the upper left corner, and the picture is streched vertically, i think this is because of the bayer-filter, i’ll try different bayer-filters-patterns the week..
…and i forgot to mention: great work!

thanks&greet
Sur3