On Tue, 28 Jan 2003, Gerd Knorr wrote:
>> However, it maps VIDEO_PALETTE_YUV420 and VIDEO_PALETTE_YUV420P
>> both into same V4L2 format. According to V4L docs, the first should be
>> interleaved and the second planar.
>Which V4L docs you are talking about?
Sorry, I wasn't clear: the header file videodev.h (in kernel 2.4.20).
It quite clearly indicates that all VIDEO_PALETTE_*P formats should be
planar and nothing else.
>As far I know VIDEO_PALETTE_YUYV (+VIDEO_PALETTE_YUV422) and
>VIDEO_PALETTE_UYVY are the packed pixel (i.e. interleaved) ones and
>the others planar.
^-- ie. VIDEO_PALETTE_YUV420 and VIDEO_PALETTE_YUV411, too
Ok, so videodev.h header file is incorrect when it says
#define VIDEO_PALETTE_PLANAR 13 /* start of planar entries */
#define VIDEO_PALETTE_COMPONENT 7 /* start of component entries */
which indicates that formats 10-11 are component (packed pixel),
including the two above.
>> Same thing happens for
>> VIDEO_PALETTE_YUV411 and VIDEO_PALETTE_YUV411P.
>I don't see any mapping for VIDEO_PALETTE_YUV411 in my version of the
>file ...
Maybe you looked function pixelformat_to_palette() while I looked
palette_to_pixelformat()? Anyway, this v4l_compat.c (dated Mar 31 2002) I
just downloaded includes these two formats too.
>HI240 is a 6x6x6 dithered color cube, 8 bit/pixel.
What is the color order, how wrong is this:
red = h % 6;
green = (h/6) % 6;
blue = (h/6/6);
where h is HI240-pixel? (just guessing the color order, could you correct
me if I'm wrong, thanks). Also I'm not quite sure about the meaning of
"dithered" in this context (does it mean that the contents of HI240-images
are usually dithered?).
