rgb2ycbcr
converts
RGB
color, greyscale, or bi-level
TIFF
images to YCbCr images by transforming and sampling pixel data. If multiple
files are specified on the command line each source file is converted to a
separate directory in the destination file.
By default, chrominance samples are created by sampling
2 by 2 blocks of luminance values; this can be changed with the
-h
and
-v
options.
Output data are compressed with the
PackBits
compression scheme, by default; an alternate scheme can be selected with the
-c
option.
By default, output data are compressed in strips with
the number of rows in each strip selected so that the
size of a strip is never more than 8 kilobytes;
the
-r
option can be used to explicitly set the number of
rows per strip.
OPTIONS
-c
Specify a compression scheme to use when writing image data:
-c none
for no compression,
-c packbits
for the PackBits compression algorithm (the default),
-c jpeg
for the JPEG compression algorithm,
-c zip
for the deflate compression algorithm,
and
-c lzw
for Lempel-Ziv & Welch.
-h
Set the horizontal sampling dimension to one of: 1, 2 (default), or 4.
-r
Write data with a specified number of rows per strip;
by default the number of rows/strip is selected so that each strip
is approximately 8 kilobytes.
-v
Set the vertical sampling dimension to one of: 1, 2 (default), or 4.
