MJPEG Tools Svn

1. updated usage-information
2. activated code-fragments missing in the last commit

various improvements

Field swap (-x) option to deal with broken mjpeg files/cards

Add casts to quiet gcc about the 5th arg to dv_decode_full_frame. It needs to be an array
of uint16_t but the libdv prototype still says 'int'.

Cleanup a little by removing the ->sampling code added in an attempt to deal
with libdv's mishandling of PALDV. Also remove the YUV4 references. Quicktime
says YUV4 is a 4:2:0 type but lav_io.c was treating it as 4:2:2 (and nothing
known today produced YUV4 anyhow - it's marked as obsolete/invalide in
Quicktime). Also cleanup a little by removing the 'check_YUV420_input' function
and single reference - that actually did NOT check if the input was 4;2:0 at
all! All that did was make sure a frame buffer could be malloc'd - not worth
the extra code since a ~500KB malloc failure will be noticed very quickly.

YV12/YUY2 autodetection patch from lucabon at infinito dot it.

Fix a typo and also clarify the comment when dealing with unknown chroma type
from a DV file (basically means a broken/corrupt file).

Continue trying to straighten out the libdv mess. Use the 'decoder->sampling'
value set up by 'dv_parse_header' instead of making assumptions (or guesses)
about how libdv was compiled

LIBDV_PAL_YV12 goes away - it was badly broken and libdv seems to do things
a different way now.

gcc4 caught an unused variable:
n.c:347: warning: unused variable 'delta'