y4mcolorbars(1) [suse man page]
y4mcolorbars(1) MJPEG tools manual y4mcolorbars(1) NAME
y4mcolorbars - Create a YUV4MPEG2 stream containing a colorbar test pattern SYNOPSIS
y4mcolorbars [options] DESCRIPTION
y4mcolorbars creates a YUV4MPEG2 stream consisting entirely of frames containing a colorbar test pattern. The pattern attempts to repro- duce the standard SMPTE EG-1-1990 colorbar test signal as faithfully as possible, given the constraints of the Y'CbCr colorspace. 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. Common rates are: 24000:1001 - NTSC 3:2 pulldown converted film 24:1 - native film 25:1 - PAL/SECAM 30000:1001 - NTSC video [default] 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. Common ratios are: 1:1 - square pixels (e.g. computer graphics) 10:11 - CCIR-601 NTSC [default] 59:54 - CCIR-601 PAL -I x Set interlacing mode, used to interpret the PPM image(s), and also encoded in output stream. p - progressive, non-interlaced [default] t - top/upper-field-first interlaced b - bottom/lower-field-first interlaced -Q n Data to place in the "-I/+Q" patches in the bottom row of the pattern: 0 - -I and +Q at 20% (20IRE) [default] 1 - -I and +Q at 50% (50IRE) 2 - +Cb and +Cr at 100% -S mode Set chroma subsampling mode. 444 - 4:4:4 (no subsampling) [default] 420jpeg - 4:2:0 JPEG/MPEG-1, interstitial cositing 420mpeg2 - 4:2:0 MPEG-2, horizontal cositing The supported subsampled modes use a lousy subsampling filter; better results will be achieved by passing the default 4:4:4 output to a scaler which supports subsampling, such as y4mscaler(1). -v [0,1,2] Set verbosity level. 0 - warnings and errors only. 1 - add informative messages, too. [default] 2 - add chatty debugging message, too. EXAMPLES
To create and display 200 frames of colorbars corresponding to a top-field-first interlaced 4:3 NTSC source: y4mcolorbars -n 200 -It -S 420jpeg | yuvplay To create and display 200 frames of colorbars corresponding to a bottom-field-first interlaced 4:3 PAL source: y4mcolorbars -n 200 -H 576 -F 25:1 -A 59:54 -Ib | yuvplay BUGS
First, it's not clear to the author (who hasn't actually ever seen the SMPTE EG-1-1990 document itself) what the absolute excursion of the -I and +Q regions is supposed to be; however, the phase is correct, and that should be the critical feature. Second, the PLUGE bars, of -4 and +4 IRE, can never be precisely synthesized --- the Y' digital space maps [16,235] over the full luma excursion, but the full luma excursion in analog space depends on whether or not 7.5 IRE NTSC setup is being used by whatever device eventually produces the analog out- put. However, the difference is within 1-bit of Y' accuracy anyway. 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), y4mscaler(1), yuv2lav(1), yuvplay(1) MJPEG Linux Square 28 April 2004 y4mcolorbars(1)
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pnmtoy4m(1) MJPEG tools manual pnmtoy4m(1) 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 inter- preted 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) MJPEG Linux Square 28 April 2004 pnmtoy4m(1)