y4mcolorbars(1)

NAME

y4mcolorbars - Create a YUV4MPEG2 stream containing a col
orbar test pattern

SYNOPSIS

y4mcolorbars [options]

DESCRIPTION

y4mcolorbars creates a YUV4MPEG2 stream consisting entirely of frames containing a colorbar test pattern.
This stream is ready for further processing by the
mpeg2enc(1) MPEG encoder and image processing filters like yuvscaler(1).

Output is to stdout to facilitate piping to other MJPEG
tools.

OPTIONS

y4mcolorbars accepts the following options:

-n num

Output a total of 'num' output frames. (default: 1)

-F n:d

Set framerate encoded in output stream, as an exact
integer ratio. (default: 30000:1001) Common rates
are:

24000:1001 - NTSC 3:2 pulldown converted film

24:1 - native film
25:1 - PAL/SECAM

30000:1001 - NTSC video

50:1 - PAL field rate

60000:1001 - NTSC field rate

-W w Set frame width. (default: 720)

-H h Set frame height. (default: 480)

-A n:d

Set pixel aspect ratio encoded in output stream, as
an exact integer ratio. (default: 10:11) Common
ratios are:

1:1 - square pixels (computer graphics)

10:11 - CCIR-601 NTSC
59:54 - CCIR-601 PAL

-I x Set interlacing mode, used to interpret the PPM

image(s), and also encoded in output stream.
(default: 'p')

p - progressive, non-interlaced
t - top/upper-field-first interlaced
b - bottom/lower-field-first interlaced

-S mode

Set chroma subsampling mode. (default: 420_jpeg)

420_jpeg - 4:2:0 JPEG/MPEG-1, interstitial cositing

420_mpeg2 - 4:2:0 MPEG-2, horizontal cositing

Changing the subsampling mode from the default won't
necessarily make anything better. This option is
just for experimenting.

-v [0,1,2]

Set verbosity level.

0 = warnings and errors only.
1 = add informative messages, too.
2 = add chatty debugging message, too.

EXAMPLES

To create and display 200 frames of colorbars correspond
ing to a top-field-first interlaced 4:3 NTSC source:

y4mcolorbars -n 200 -It | yuvplay

To create and display 200 frames of colorbars correspond
ing to a bottom-field-first interlaced 4:3 PAL source:

y4mcolorbars -n 200 -H 576 -F 25:1 -A 59:54 -Ib
yuvplay

AUTHOR

This man page was written by Matt Marjanovic.
If you have questions, remarks, problems or you just want
to contact the developers, the main mailing list for the
MJPEG-tools is:

mjpeg-users@lists.sourceforge.net

For more info, see our website at

http://mjpeg.sourceforge.net

SEE ALSO

mjpegtools(1), mpeg2enc(1), yuvscaler(1), yuv2lav(1), yuvplay(1)

MJPEG Linux Square 13 November 2001 y4mcolorbars(1)