xenial (1) pnmtoy4m.1.gz

Provided by: mjpegtools_2.1.0+debian-4_amd64 bug

NAME

       pnmtoy4m - Convert PNM/PAM images to YUV4MPEG2 stream

SYNOPSIS

       pnmtoy4m [options] [ filename ]

DESCRIPTION

       pnmtoy4m  converts one or more raw PPM, PGM, PBM, or PAM images into a YUV4MPEG2 stream ready for further
       processing by other video tools.  These three (or four) image formats are  collectively  referred  to  as
       "PNM images".

       Output  is  to  stdout  to  facilitate  piping  to other MJPEG tools.  The size of the output frame(s) is
       determined from the (first) input image.

       Input is a 'raw' format PNM image, read from stdin or from the optional filename.  The input may  contain
       multiple  PNM images concatenated together; pnmtoy4m will read and process them sequentially.  All images
       must have identical size and format.  Input images can be interpreted as whole progressive frames,  pairs
       of  interleaved  fields,  or  as  sequential  fields  (read  in  pairs  of images) to be output as either
       interlaced or progressive frames.  PPM and PGM images must have 8 bits per channel (i.e. 'maxval' must be
       255).

       PPM  input  images should be in the usual R'G'B' colorspace.  They are converted to the Y'CbCr colorspace
       (ITU-R BT.601) before being output to a "4:4:4" (non-subsampled) YUV4MPEG2 stream.  If chroma subsampling
       is  required  (e.g.  to  4:2:0  for  MPEG),  the output should be further piped through a program such as
       y4mscaler.

       PGM images should be in the standard full-range ([0,255]) grayscale colorspace.  PGM and PBM images  will
       be converted to BT.601 luma and output as "MONO" (luma-only) YUV4MPEG2 streams.

       The  PAM format is a newer superset of the PNM formats; the precise contents of a PAM image is defined by
       the TUPLTYPE header tag.  pnmtoy4m handles TUPLTYPE "GRAYSCALE" as PGM, "RGB" as PPM, and "RGB_ALPHA"  as
       PPM  with  an  8-bit alpha channel.  (The alpha channel is converted to BT.601 luma as is appropriate for
       YUV4MPEG2 streams.)

       pnmtoy4m and y4mtopnm are inverses of each other; you can pipe the output of  one  into  the  other,  and
       vice-versa.   Note  that the colorspace operations are lossy in both directions.  And, when converting to
       PNM, information on interlacing and sample aspect ratio is lost (but can be  reconstructed  by  supplying
       command-line arguments to pnmtoy4m).

OPTIONS

       pnmtoy4m accepts the following options:

       -o num
            Frame offset:  skip output of the first 'num' frames.  (default: 0)

       -n num
            Output a total of 'num' output frames.  Use '0' to specify all frames.  (default: 0)

       -B   Interpret data as being  BGR rather than RGB.

       -r   Repeat  last  input  frame  until output is complete.  If '-n 0' is also specified, last input frame
            will be repeated forever.

       -D x Treat each PNM image as a single (de-interleaved) field instead  of  a  full  frame.   The  argument
            specifies the interpretation:
             t - the first image is a top-field
             b - the first image is a bottom-field

            With  this option, two input images will be required per output frame.  Be careful:  mismatched "-I"
            and "-D" options can invert the temporal or spatial order of the fields (or both).

       -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

       -A n:d
            Set pixel aspect ratio encoded in output stream, as an exact integer ratio.  (default:  1:1)  Common
            ratios are:
                 1:1  - square pixels (computer graphics)
                10:11 - CCIR-601 NTSC
                59:54 - CCIR-601 PAL

       -I x Set the output interlacing mode, encoded in the output stream.  (Default is to match "-D" if  given,
            or 'p' if not.)
             p - progressive, non-interlaced
             t - top/upper-field-first interlaced
             b - bottom/lower-field-first interlaced

       -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 convert a file containing a single PPM file into a stream of 15 (identical) frames:

            pnmtoy4m -n 15 -r some-image.ppm

       To  convert a series of Targa format images (in the current directory) to a YUV4MPEG2 stream displayed by
       yuvplay:

            ls *.tga | xargs -n1 tgatoppm | pnmtoy4m | yuvplay

AUTHOR

       This manual 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

       pam(5),   pbm(5),   pgm(5),   pnm(5),  ppm(5),  y4mtopnm(1),  mjpegtools(1),  mpeg2enc(1),  y4mscaler(1),
       yuv2lav(1), yuvplay(1)