qmp3info(1) [debian man page]
qmp3info(1) quelcom man pages qmp3info(1) NAME
qmp3info - show info from mp3 files SYNOPSIS
qmp3info [option]... file... DESCRIPTION
qmp3info reads a list of mp3 files and prints on standard output some of its parameters: version, layer, sample rate, bit rate, duration and tag. a duration summary is appended at the end of the list. OPTIONS
-c, --check check the entire stream (slower but accurate). all the frames of the stream are read and the total duration is exactly computed. this option is automatically activated if the stream appears to be vbr (have different bit rate frames). -h, --help show a brief help and exit. -s, --summary-only show only the summary. do not show info from every file. -v, --verbose show also the number of bytes and frames. -V, --version show version and exit. BUGS
variable bit rate (vbr) streams are detected by reading the initial (5) frames in the stream. if their bit rate field differs, the --check option is activated automatically. if vbr is not detected, qmp3info reads only the first frame in the stream and calculates the duration supposing that (1) the entire stream is composed by valid frames and (2) all the frames have the same bit rate. this is a fast way to compute the duration of the stream, but it is not exact: there's an error of 0.3% aprox. if you want to be accurate, or qmp3info is unable to detect a vbr stream, use --check. tests have been done only with mpeg version 1 layer iii streams, though it may (or not) work with other versions or layers. AUTHOR
dmanye@etse.urv.es http://www.etse.urv.es/~dmanye/quelcom/quelcom.html SEE ALSO
qmp3join(1), qmp3cut(1), qmp3check(1), qmp3report(1) qwavinfo(1), qwavjoin(1), qwavcut(1), qwavsilence(1), qwavfade(1), qwavheaderdump(1) quelcom 0.4.0 february 2001 qmp3info(1)
Check Out this Related Man Page
yuvfps(1) MJPEG tools manual yuvfps(1) NAME
yuvfps - Converts to a different frame rate SYNOPSIS
yuvfps [-r Num:Den] [-s Num:Den] [-i Interlacing] [-I Interlacing] [-c] [-n] [-w] [-v 0-2] [-h] DESCRIPTION
yuvfps is a general (UP or DOWN) resampling utility that is provided to allow the generation of video streams with the frame rates required for each standard video format. yuvfps reads a YUV4MPEG stream from the standard input and outputs a YUV4MPEG stream to the standard output in which frames from the original ones are skipped (downsampling) or duplicated (upsampling). This allows for other mjpegtools that require a specific frame rate to process the stream. yuvfps uses by default Bresenham's algorithm to do the resampling so that the new video stream is similar to the original one. Note, how- ever, that downscaling is a non-reversible operation because frames are dropped. Moreover, the resulting video stream may not have the exact same duration as the original one if the new frame rate is not a whole multiple of the original rate. As an alternative to simply dropping or duplicating frames each output frame/field can be produced as a weighted average of the two tempo- rally closest input frames/fields. In this mode, yuvfps can also change the interlacing mode of the stream. yuvfps also can "fix" the framerate specified in the YUV4MPEG header. This allows for the generation of effects (fast-forwarding, slow motion) and also when the source stream has some framerate that is very close, but not exactly, the rate required for some standard video (for example, 24.9 vs 25). OPTIONS
-r Num:Den Specifies the resulting stream frame rate. -s Num:Den Ignores the frame rate in the input stream and assumes this frame rate for the input stream. -i Interlacing Specifies the interlacing mode of the resulting stream. The interlacing mode can be changed only when using the weighted average resampling mode (the -w option). p - progressive (non-interlaced) t - top-field first b - bottom-field first -I Interlacing Ignores the interlacing mode information in the input stream and assumes this interlacing mode for the input stream. The possible values are the same as for the -i option. -c Changes the stream header frame rate and interlacing mode in the output stream but copies frames from the original stream without changes. The -r and -i options specify the frame rate and interlacing mode for the output stream header. -n By default yuvfps tries to find a normalized framerate. Some programs create framerates like: 29969909:1000000 which is actually th typical NTSC framerate of 30000:1001. yuvfps prints out the normalizes values and the original when it starts. If you think the nor- malized value is not correct and want yuvfps to use the original given number you have to add that option. So yuvfps does not try to normalize the values. -w Produce each output frame/field as a weighted average of the two temporally closest input frames/fields instead of simply dropping or duplicating frames. The blending of two adjacent frames/fields reduces visible stepping compared to the default drop/duplicate algorithm but as a drawback it makes fast moving objects appear blurred and is much slower. -v [0,1,2] Set verbosity level. 0 = warnings and error messages only. 1 = add informative messages, like the framerate conversation information. 2 = add chatty debugging message, too. AUTHOR
This man page was written by Alfonso Garcia-Patino Barbolani. Johannes Lehtinen added information about the weighted average resampling mode and the related options. 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
yuvscaler(1), mjpegtools(1), lavpipe(1), lav2yuv(1) mpeg2enc(1) MJPEG Linux Square 8 Jan 2006 yuvfps(1)