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|
diff --git a/userguide/libnetpbm_ug.html b/userguide/libnetpbm_ug.html
index 94d4fd4..bb1c77e 100644
--- a/userguide/libnetpbm_ug.html
+++ b/userguide/libnetpbm_ug.html
@@ -374,7 +374,7 @@ plain format.
<H2 id="reference">Reference</h2>
<p>The <a href="libnetpbm_image.html">Libnetpbm Netpbm Image
-Processing Manual</a> describes the the <b>libnetpbm</b> functions for
+Processing Manual</a> describes the <b>libnetpbm</b> functions for
processing image data.
<p>The <a href="libpm.html">Libnetpbm Utility Manual</a>
diff --git a/userguide/pamfunc.html b/userguide/pamfunc.html
index d158393..e0fe96a 100644
--- a/userguide/pamfunc.html
+++ b/userguide/pamfunc.html
@@ -57,7 +57,7 @@ output image.
and bit string (such as and with 01001000). For the arithmetic functions, the
function arguments and results are the fraction that a sample is of the
maxval, i.e. normal interpretation of PAM tuples. But for the bit string
-functions, the value is the the bit string whose value as a binary cipher is
+functions, the value is the bit string whose value as a binary cipher is
the sample value, and the maxval indicates the width of the bit string.
<h4>Arithmetic functions</h4>
diff --git a/userguide/pbmtog3.html b/userguide/pbmtog3.html
index ee2bd6b..3b23517 100644
--- a/userguide/pbmtog3.html
+++ b/userguide/pbmtog3.html
@@ -77,7 +77,7 @@ You cannot specify both.
<H2 id="history">HISTORY</H2>
<p>Before Netpbm 10.79 (June 2017), there was a different program by the same
-name in Netpbm, which was written by by Paul Haeberli
+name in Netpbm, which was written by Paul Haeberli
<<A HREF="mailto:paul@manray.sgi.com">paul@manray.sgi.com</A>> in 1989
and then modified extensively by others.
diff --git a/userguide/ppmtompeg.html b/userguide/ppmtompeg.html
deleted file mode 100644
index a1ce767..0000000
--- a/userguide/ppmtompeg.html
+++ /dev/null
@@ -1,1291 +0,0 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN">
-<HTML>
-<HEAD>
-<TITLE>Ppmtompeg User Manual</TITLE>
-</HEAD>
-<BODY>
-<H1>Ppmtompeg</H1>
-Updated: 23 July 2006
-<BR>
-<A HREF="#index">Table Of Contents</A>
-
-<H2>NAME</H2>
-ppmtompeg - encode an MPEG-1 bitstream
-
-<H2 id="synopsis">SYNOPSIS</H2>
-
-<B>ppmtompeg</B>
-[<I>options</I>]
-<I>parameter-file</I>
-
-<H2 id="description">DESCRIPTION</H2>
-
-<p>This program is part of <a href="index.html">Netpbm</a>.
-
-<P><B>ppmtompeg</B> produces an MPEG-1 video stream. MPEG-1 is the
-first great video compression method, and is what is used in Video CDs
-(VCD). <b>ppmtompeg</b> originated in the year 1995. DVD uses a more
-advanced method, MPEG-2. There is an even newer method called MPEG-4
-which is also called Divx. I don't know where one finds that used.
-
-<p>There's technically a difference between a compression method for
-video and an actual file (stream) format for a movie, and I don't know
-if it can be validly said that the format of the stream
-<b>ppmtompeg</b> produces is MPEG-1.
-
-<p>Mencoder from the <a href="http://www.mplayerhq.hu">Mplayer
-package</a> is probably superior for most video format generation
-needs, if for no other reason than that it is more popular.
-
-<p>The programming library <a href="http://pm2v.free.fr"><b>PM2V</b></a>
-generates MPEG-2 streams.
-
-<p>Use <a href="http://www.mplayerhq.hu">Mplayer</a> (not part of Netpbm)
-to do the reverse conversion: to create a series of PNM files from an MPEG
-stream.
-
-<p><i>param_file</i> is a parameter file which includes a list of
-input files and other parameters. The file is described in detail
-below.
-
-<P>To understand this program, you need to understand something about
-the complex MPEG-1 format. One source of information about this
-standard format is the section Introduction to MPEG in the <a
-href="http://www.faqs.org/faqs/compression-faq">Compression FAQ</a>.
-
-<H2 id="options">OPTIONS</H2>
-
-<p>The <b>-gop</b>, <b>-combine_gops</b>, <b>-frames</b>, and
-<b>-combine_frames</b> options are all mutually exclusive.
-
-<DL COMPACT>
-<DT><B>-stat stat_file</B>
-
-<DD>This option causes <b>ppmtompeg</b> to append the statistics that
-it write to Standard Output to the file <I>stat_file</I> as well. The
-statistics use the following abbreviations: bits per block (bpb), bits
-per frame (bpf), seconds per frame (spf), and bits per second (bps).
-
-<p>These statistics include how many I, P, and B frames there were,
-and information about compression and quality.
-
-
-<DT><B>-quiet</b> <i>num_seconds</i>
-
-<DD> causes <b>ppmtompeg</b> not to report remaining time more often
-than every <i>num_seconds</i> seconds (unless the time estimate rises,
-which will happen near the beginning of the run). A negative value
-tells <b>ppmtompeg</b> not to report at all. 0 is the default
-(reports once after each frame). Note that the time remaining is an
-estimate and does not take into account time to read in frames.
-
-<DT><B>-realquiet</B> <DD> causes <b>ppmtompeg</b> to run silently,
-with the only screen output being errors. Particularly useful when
-reading input from stdin.
-
-<DT>
-<B>-no_frame_summary</B>
-
-<DD> This option prevents <b>ppmtompeg</b> from printing a summary
-line for each frame
-
-<DT><B>-float_dct</B>
-
-<DD> forces <b>ppmtompeg</b> to use a more accurate, yet more
-computationally expensive version of the DCT.
-
-<DT><B>-gop</b> <i>gop_num</i>
-<DD>
-causes <b>ppmtompeg</b> to encode only the numbered GOP (first GOP is 0). The
-parameter file is the same as for normal usage. The output file will be
-the normal output file with the suffix <b>.gop.</b><i>gop_num</i>.
-<b>ppmtompeg</b> does not output any sequence information.
-
-<DT><B>-combine_gops</B>
-
-<DD> causes <b>ppmtompeg</b> simply to combine some GOP files into a
-single MPEG output stream. <b>ppmtompeg</b> inserts a sequence header
-and trailer. In this case, the parameter file needs only to contain
-the SIZE value, an output file, and perhaps a list of input GOP
-files (see below).
-
-If you don't supply a list of input GOP files is used, then
-<b>ppmtompeg</b> assumes you're using the same parameter file you used
-when you created the input (with the <b>-gop</b> option) and
-calculates the corresponding gop filenames itself. If this is not the
-case, you can specify input GOP files in the same manner as normal
-input files -- except instead of using INPUT_DIR, INPUT, and
-END_INPUT, use GOP_INPUT_DIR, GOP_INPUT, and GOP_END_INPUT. If no
-input GOP files are specified, then the default is to use the output
-file name with suffix <b>.gop.</b><i>gop_num</i>, with <i>gop_num</i>
-starting from 0, as the input files.
-
-<p>Thus, unless you're mixing and matching GOP files from different
-sources, you can simply use the same parameter file for creating the
-GOP files (<b>-gop</b>) and for later turning them into an MPEG stream
-(<b>-combine_gops</b>).
-
-
-<DT><B>-frames <i>first_frame</i> <i>last_frame</i></B>
-
-<DD>This option causes <b>ppmtompeg</b> to encode only the frames numbered
-<i>first_frame</i> to <i>last_frame</i>, inclusive. The parameter
-file is the same as for normal usage. The output will be placed in
-separate files, one per frame, with the file names being the normal
-output file name with the suffix <b>.frame.</b><i>frame_num</i>. No
-GOP header information is output. (Thus, the parameter file need not
-include the GOP_SIZE value)
-
-<p>Use <b>ppmtompeg -combine_frames</b> to combine these frames later into
-an MPEG stream.
-
-
-<DT><B>-combine_frames</B>
-
-<DD> This option causes <b>ppmtompeg</b> simply to combine some
-individual MPEG frames (such as you might have created with an earlier
-run of <b>ppmtompeg -frames</b>) into a single MPEG stream. Sequence
-and GOP headers are inserted appropriately. In this case, the
-parameter file needs to contain only the SIZE value, the GOP_SIZE
-value, an output file, and perhaps a list of frame files (see below).
-
-<p>The parameter file may specify input frame files in the same manner
-as normal input files -- except instead of using INPUT_DIR, INPUT, and
-END_INPUT, use FRAME_INPUT_DIR, FRAME_INPUT, and FRAME_END_INPUT. If
-no input frame files are specified, then the default is to use the
-output file name with suffix <b>.frame.</b><i>frame_num</i>, with
-<i>frame_num</i> starting from 0, as the input files.
-
-
-
-<DT><B>-nice</B>
-
-<DD>This option causes <b>ppmtompeg</b> to run any remote processes
-"nicely," i.e. at low priority. (This is relevant only if you are
-running <b>ppmtompeg</b> in parallel mode. Otherwise, there are no
-remote processes). See 'man nice.'
-
-<DT><B>-max_machines <i>num_machines</i></B>
-
-<DD>This option causes <b>ppmtompeg</b> to use no more than
-<i>num_machines</i> machines as slaves for use in parallel encoding.
-
-<DT><B>-snr</B>
-
-<DD>This option causes <b>ppmtompeg</b> to include the signal-to-noise
-ratio in the reported statistics. Prints SNR (Y U V) and peak SNR (Y
-U V) for each frame. In summary, prints averages of luminance only
-(Y). SNR is defined as 10*log(variance of original/variance of
-error). Peak SNR is defined as 20*log(255/RMSE). Note that
-<b>ppmtompeg</b> runs a little slower when you use this option.
-
-<DT><B>-mse</B>
-
-<DD>This option causes <b>ppmtompeg</b> to report the mean squared
-error per block. It also automatically reports the quality of the
-images, so there is no need to specify <b>-snr</b> then.
-
-<DT><B>-bit_rate_info</b> <i>rate_file</i>
-
-<DD> This option makes <b>ppmtompeg</b> write bit rate information
-into the file <i>rate_file</i>. Bit rate information is bits per frame, and
-also bits per I-frame-to-I-frame.
-
-<DT><B>-mv_histogram</B>
-
-<DD> This option causes <b>ppmtompeg</b> to print a histogram of the
-motion vectors as part of statistics. There are three histograms --
-one for P frame, one for forward B frame, and one for backward B frame
-motion vectors.
-
-<p>The output is in the form of a matrix, each entry corresponding to one
-motion vector in the search window. The center of the matrix
-represents (0,0) motion vectors.
-
-<dt><b>-debug_sockets</b>
-
-<dd>This option causes <b>ppmtompeg</b> to print to Standard Output
-messages that narrate the communication between the machines when you run
-<b>ppmtompeg</b> in <a href="#parallel">parallel mode</a>.
-
-<dt><b>-debug_machines</b>
-
-<dd>This option causes <b>ppmtompeg</b> to print to Standard Output
-messages that narrate the progress of the conversion on the various
-machines when you run <b>ppmtompeg</b> in <a href="#parallel">parallel
-mode</a>.
-
-</DL>
-
-<H2 id="parmfile">PARAMETER FILE</H2>
-
-<P>The parameter file <strong>must</strong> contain the following
-lines (except when using the <b>-combine_gops</b> or <b>-combine_frames</b>
-options):
-
-<DL COMPACT>
-
-<DT><B>PATTERN</b> <i>pattern</i>
-
-<DD>This statement specifies the pattern (sequence) of I frames, P frames,
-and B frames. <i>pattern</i> is just a sequence of the letters I, P, and
-B with nothing between. Example:
-
-<pre>
- PATTERN IBBPBBPBBPBBPBB
-</pre>
-
-<p>See <a href="#ipb">I Frames, P Frames, B Frames</a>.
-
-<DT><B>OUTPUT</b> <i>output file</i>
-<DD>This names the file where the output MPEG stream goes.
-
-<DT><B>INPUT_DIR</b> <i>directory</i>
-
-<DD>This statement tells where the input images (frames) come from.
-If each frame is in a separate file, <i>directory</i> is the directory
-where they all are. You may use <b>.</b> to refer to the current
-directory. A null <i>directory</i> refers to the root directory of the
-system file tree.
-
-<p>To have <b>ppmtompeg</b> read all the frames serially from Standard
-Input, specify
-<pre>
- INPUT_DIR stdin
-</pre>
-
-<DT><B>INPUT</b>
-<DD>
-This line must be followed by a list of the input files (in display order)
-and then the line <B>END_INPUT</B>.
-
-<p>There are three types of lines between INPUT and END_INPUT. First,
-a line may simply be the name of an input file. Second, the line
-may be of the form <i>single_star_expr</i>
-<b>[</b><i>x</i><b>-</b><i>y</i><b>]</b>.
-<i>single_star_expr</i> can have a single <b>*</b> in it. It is
-replaced by all the numbers between x and y inclusive. So, for
-example, the line <b>tennis*.ppm [12-15]</b> refers to the files
-tennis12.ppm, tennis13.ppm, tennis14.ppm, tennis15.ppm.
-
-<p>Uniform zero-padding occurs, as well. For example, the line
-<b>football.*.ppm [001-130]</b> refers to the files football.001.ppm,
-football.002.ppm, ..., football.009.ppm, football.010.ppm, ...,
-football.130.ppm.
-
-<p>The third type of line is: <i>single_star_expr</i>
-<b>[</b><i>x</i><b>-</b><i>y</i><b>+</b><i>s</i><b>]</b>, where the
-line is treated exactly as above, except that we skip by <i>s</i>. Thus, the
-line <b>football.*.ppm [001-130+4]</b> refers to the files
-football.001.ppm, football.005.ppm, football.009.ppm,
-football.013.ppm, etc.
-
-<p>Furthermore, a line may specify a shell command to execute to
-generate lines to be interpreted as described above, as if those lines
-were in the parameter file instead. Use back ticks, like in the
-Bourne Shell, like this:
-
-<pre>
- `cat myfilelist`
-</pre>
-
-<p>
-If input is from Standard Input (per the <b>INPUT_DIR</b> statement),
-<b>ppmtompeg</b> ignores the <B>INPUT</b>/<b>END_INPUT</b> block, but
-it still must be present.
-
-<DT><b>BASE_FILE_FORMAT</b> {<b>PPM</b> | <b>PNM</b> | <b>YUV</b> |
- <b>JPEG</b> | <b>JMOVIE</b>}
-
-<DD><B>ppmtompeg</b> must convert all input files to one of the
-following formats as a first step of processing: PNM, YUV, JPEG(v4),
-or JMOVIE. (The conversion may be trivial if your input files are
-already in one of these formats). This line specifies which of the
-four formats. PPM is actually a subset of PNM. The separate
-specification is allowed for backward compatibility. Use PNM instead
-of PPM in new applications.
-
-<DT><b>INPUT_CONVERT</b> <i>conversion_command</i>
-
-<DD>You must specify how to convert a file to the base file format.
-If no conversion is necessary, then you would just say:
-
- <pre>
- INPUT_CONVERT *
- </pre>
-
-<p>Otherwise, <i>conversion_command</i> is a shell command that causes
-an image in the format your specified with <B>BASE_FILE_FORMAT</b> to
-be written to Standard Output. <b>ppmtompeg</b> executes the command
-once for each line between <b>INPUT</b> and <b>END_INPUT</b> (which is
-normally, but not necessarily, a file name). In the conversion
-command, <b>ppmtompeg</b> replaces each '*' with the contents of that
-line.
-
- If you had a bunch of gif files, you might say:
- <pre>
- INPUT_CONVERT giftopnm *
- </pre>
-
- If you have a bunch of separate a.Y, a.U, and a.V files (where
- the U and V have already been subsampled), then you might say:
-
- <pre>
- INPUT_CONVERT cat *.Y *.U *.V
- </pre>
-
-<p>Input conversion is not allowed with input from stdin, so use
-
- <pre>
- INPUT_CONVERT *
- </pre>
-
-as described above.
-
-<DT><b>SIZE</b> <i>width</i><b>x</b><i>height</i>
-
-<dd>
-
-<p><i>width</i> and <i>height</i> are the width and height of each
-frame in pixels.
-
-<p>When <b>ppmtompeg</b> can get this information from the input image
-files, it ignores the <b>SIZE</b> parameter and you may omit it.
-
-<p>When the image files are in YUV format, the files don't contain
-dimension information, so <b>SIZE</b> is required.
-
-<p>When <b>ppmtompeg</b> is running in parallel mode, not all of the
-processes in the network have access to the image files, so
-<b>SIZE</b> is required and must give the same dimensions as the
-input image files.
-
-<DT><b>YUV_SIZE</b> <i>width</i><b>x</b><i>height</i>
-
-<dd>This is an obsolete synonym of <b>SIZE</b>.
-
-<DT><b>YUV_FORMAT</B> {<b>ABEKAS</b> | <b>PHILLIPS</b> | <b>UCB</B> |
- <b>EYUV</b> | <i>pattern</i>}
-
-<DD>This is meaningful only when <b>BASE_FILE_FORMAT</b> specifies
-YUV format, and then it is required. It specifies the sub-format of
-the YUV class.
-
-
-<DT><b>GOP_SIZE</b> <i>n</i>
-
-<DD><i>n</i> is the number of frames in a Group of Pictures. Except that
-because a GOP must start with an I frame, <b>ppmtompeg</b> makes a GOP as
-much longer than <i>n</i> as it has to to make the next GOP start with an
-I frame.
-
-<p>Normally, it makes sense to make your GOP size a multiple of your
-pattern length (the latter is determined by the PATTERN parameter file
-statement).
-
-<p>See <a href="#gop">Group Of Pictures</a>.
-
-<DT><b>SLICES_PER_FRAME</b> <i>n</i>
-<dd><i>n</i> is roughly the number of slices per frame. Note, at
-least one MPEG player may complain if slices do not start at the left
-side of an image. To ensure this does not happen, make sure the
-number of rows is divisible by SLICES_PER_FRAME.
-
-<DT><b>PIXEL</b> {<b>FULL</b> | <b>HALF</b>}
-
-<dd>use half-pixel motion vectors, or just full-pixel ones It is
-usually important that you use half-pixel motion vectors, because it
-results in both better quality and better compression.
-
-
-<DT><b>RANGE</b> <i>n</i>
-<dd>Use a search range of <i>n</i> pixels in each of the four directions
-from a subject pixel. (So the search window is a square <i>n</i>*2 pixels
-on a side).
-
-<DT><b>PSEARCH_ALG</b> {<b>EXHAUSTIVE</B> | <b>TWOLEVEL</b> |
- <b>SUBSAMPLE</b> | <b>LOGARITHMIC</b>}
-
-<dd>This statement tells <b>ppmtompeg</b> what kind of search
- technique (algorithm) to use for P frames. You select the desired
- combination of speed and compression. <b>EXHAUSTIVE</b> gives the
- best compression, but <b>LOGARITHMIC</B> is the fastest.
- <B>TWOLEVEL</B> is an exhaustive full-pixel search, followed by a
- local half- pixel search around the best full-pixel vector (the
- PIXEL option is ignored for this search technique).
-
-<DT><b>BSEARCH_ALG</b> {<b>SIMPLE</B> | <B>CROSS2</B> | <B>EXHAUSTIVE</B>}
-
-<dd>This statement tells <b>ppmtompeg</b> what kind of search
- technique (algorithm) to use for B frames. <b>SIMPLE</B> means
- find best forward and backward vectors, then interpolate.
- <B>CROSS2</B> means find those two vectors, then see what backward
- vector best matches the best forward vector, and vice versa.
- <b>EXHAUSTIVE</b> does an n-squared search and is
- <em>extremely</em> slow in relation to the others (<b>CROSS2</b>
- is about half as fast as <b>SIMPLE</B>).
-
-<DT><b>IQSCALE</b> <i>n</i>
-<dd>Use <i>n</i> as the qscale for I frames.
- See <a href="#qscale">Qscale</a>.
-
-<DT><b>PQSCALE</b> <i>n</i>
-<dd>Use <i>n</i> as the qscale for P frames.
- See <a href="#qscale">Qscale</a>.
-
-<DT><b>BQSCALE</b> <i>n</i>
-<dd>Use <i>n</i> as the qscale for B frames.
- See <a href="#qscale">Qscale</a>.
-
-<DT><b>REFERENCE_FRAME</b> {<B>ORIGINAL</B> | <b>DECODED</b>} <dd>This
-statement determines whether <b>ppmtompeg</b> uses the original images
-or the decoded images when computing motion vectors. Using decoded
-images is more accurate and should increase the playback quality of
-the output, but it makes the encoding take longer and seems to give
-worse compression. It also causes some complications with parallel
-encoding. (see the section on parallel encoding). One thing you can
-do as a trade-off is select <b>ORIGINAL</b> here, and lower the
-qscale (see <b>QSCALE</b> if the quality is not good enough.
-
-<table border="1" cellpadding="5" cellspacing="0"
-summary="comparison of original to decoded">
- <caption>Original or Decoded? (Normalized)</caption>
-<?makeman r c c c c c. ?>
-<?makeman _ ?>
- <tr align="center" bgcolor="#CCCCCC">
- <th>Reference</th>
- <th>Compression</th>
- <th>Speed</th>
- <th>Quality I</th>
- <th>Quality P</th>
- <th>Quality B</th>
- </tr>
- <tr>
- <td align="right">Decoded</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- <td align="center">969</td>
- <td align="center">919</td>
- </tr>
- <tr>
- <td align="right">Original</td>
- <td align="center">885</td>
- <td align="center">1373</td>
- <td align="center">1000</td>
- <td align="center">912</td>
- <td align="center">884</td>
- </tr>
- </table>
-
-
-
-</dl>
-
-<p>The following lines are optional:
-
-<DL>
-
-<DT><B>FORCE_ENCODE_LAST_FRAME</B>
-
-<dd>This statement is obsolete. It does nothing.
-
-<p>Before Netpbm 10.26 (January 2005), <b>ppmtompeg</b> would drop
-trailing B frames from your movie, since a movie can't end with a B
-frame. (See <a href="#ipb">I Frames, P Frames, B Frames</a>.
-You would have to specify <b>FORCE_ENCODE_LAST_FRAME</b> to stop
-that from happening and get the same function that <b>ppmtompeg</b>
-has today.
-
-
-<DT><b>NIQTABLE</b>
-
-<dd>This statement specifies a custom non-intra quantization table.
-If you don't specify this statement, <b>ppmtompeg</b> uses a default
-non-intra quantization table.
-
-<p>
-The 8 lines immediately following <b>NIQTABLE</b> specify the quantization
-table. Each line defines a table row and consists of 8 integers,
-whitespace-delimited, which define the table columns.
-
-<DT><B>IQTABLE</b>
-
-<dd>This is analogous to NIQTABLE, but for the intra quantization table.
-
-<DT><b>ASPECT_RATIO</b> <i>ratio</i>
-
-<dd>This statement specifies the aspect ratio for <b>ppmtompeg</b> to
-specify in the MPEG output. I'm not sure what this is used for.
-
-<p><i>ratio</i> must be 1.0, 0.6735, 0.7031, 0.7615, 0.8055, 0.8437,
-0.8935, 0.9157, 0.9815, 1.0255, 1.0695, 1.0950, 1.1575, or 1.2015.
-
-<DT><b>FRAME_RATE</b> <i>rate</i>
-<dd>This specifies the frame rate for <b>ppmtompeg</b> to specify in the
-MPEG output. Some players use this value to determine the playback rate.
-
-<p><i>rate</i> must be 23.976, 24, 25, 29.97, 30, 50, 59.94, or 60.
-
-<DT><b>BIT_RATE</b> <i>rate</i>
-<DD>This specifies the bit rate for Constant Bit Rate (CBR) encoding.
-
-<p><i>rate</i> must be an integer.
-
-<DT><b>BUFFER_SIZE</b> <i>size</i>
-
-<dd>This specifies the value
-<b>ppmtompeg</b> is to specify in the MPEG output for the Video
-Buffering Verifier (VBV) buffer size needed to decode the sequence.
-
-<p>A Video Verifying Buffer is a buffer in which a decoder keeps the
-decoded bits in order to match the uneven speed of the decoding with
-the required constant playback speed.
-
-<p>As <b>ppmtompeg</b> encodes the image, it simulates the decoding
-process in terms of how many bits would be in the VBV as each frame gets
-decoded, assuming a VBV of the size you indicate.
-
-<P>If you specify the <b>WARN_VBV_UNDERFLOW</b> statement,
-<b>ppmtompeg</b> issues a warning each time the simulation underflows
-the buffer, which suggests that an underflow would occur on playback,
-which suggests the buffer is too small.
-
-<P>If you specify the <b>WARN_VBV_OVERFLOW</b> statement,
-<b>ppmtompeg</b> issues a warning each time the simulation overflows
-the buffer, which suggests that an overflow would occur on playback,
-which suggests the buffer is too small.
-
-<DT><B>WARN_VBV_UNDERFLOW</B>
-<DT><B>WARN_VBV_OVERFLOW</B>
-
-<dd>See <b>BUFFER_SIZE</b>.
-
-<p>These options were new in Netpbm 10.26 (January 2005). Before that,
-<b>ppmtompeg</b> issued the warnings always.
-
-</DL>
-
-
-The following statements apply only to parallel operation:
-
-<DL>
-
-<DT><b>PARALLEL</b>
-
-<dd>This statement, paired with <b>END PARALLEL</B>, is what causes
-<b>ppmtompeg</b> to operate in parallel mode. See <a
-href="#parallel">Parallel Operation</a>.
-
-<dt><b>END PARALLEL</b>
-
-<DD>This goes with <b>PARALLEL</b>.
-
-<DT><b>PARALLEL_TEST_FRAMES</b> <i>n</i>
-
-<dd>The master starts off by measuring each slave's speed. It does
-this by giving each slave <i>n</i> frames to encode and noting how
-long the slave takes to finish. These are not just test frames,
-though -- they're real frames and the results become part of the
-output.
-<b>ppmtompeg</b> is old and measures time in undivided seconds, so
-to get useful timings, specify enough frames that it will take at
-least 5 seconds to process them. The default is 10.
-
-<p>If you specify <b>FORCE_I_ALIGN</b>, <b>ppmtompeg</b> will increase
-the test frames value enough to maintain the alignment.
-
-<p>If there aren't enough frames for every slave to have the indicated
-number of test frames, <b>ppmtompeg</b> will give some slaves fewer.
-
-
-<DT><b>PARALLEL_TIME_CHUNKS</b> <i>t</i>
-
-<dd>When you specify this statement, the master attempts to feed work
-to the slaves in chunks that take <i>t</i> seconds to process. It uses
-the speed measurement it made when it started up (see PARALLEL_TEST_FRAMES)
-to decide how many frames to put in the chunk. This statement obviously
-doesn't affect the first batch of work sent to each slave, which is the
-one used to measure the slave's speed.
-
-<p>Smaller values of <i>t</i> increase communication, but improve load
-balancing. The default is 30 seconds.
-
-<p>You may specify only one of PARALLEL_TIME_CHUNKS, PARALLEL_CHUNK_TAPER,
-and PARALLEL_PERFECT. PARALLEL_CHUNK_TAPER is usually best.
-
-<DT><b>PARALLEL_CHUNK_TAPER</b>
-
-<DD>When you specify this statement, the master distributes work like
-with PARALLEL_TIME_CHUNKS, except that the master chooses the number
-of seconds for the chunks. It starts with a large number and, as it
-gets closer to finishing the job, reduces it. That way, it reduces
-scheduling overhead when precise scheduling isn't helpful, but still
-prevents a slave from finishing early after all the work has already
-been handed out to the other slaves, and then sitting idle while
-there's still work to do.
-
-<p>You may specify only one of PARALLEL_TIME_CHUNKS, PARALLEL_CHUNK_TAPER,
-and PARALLEL_PERFECT. PARALLEL_CHUNK_TAPER is usually best.
-
-
-<DT><b>PARALLEL_PERFECT</b>
-
-<dd>If this statement is present, <b>ppmtompeg</b> schedules on the
-assumption that each machine is about the same speed. The master will
-simply divide up the frames evenly between the slaves -- each
-slave gets the same number of frames. If some slaves are faster than
-others, they will finish first and remain idle while the slower slaves
-continue.
-
-<p>This has the advantage of minimal scheduling overhead. Where slaves
-have different speeds, though, it makes inefficient use of the fast
-ones. Where slaves are the same speed, it also has the disadvantage
-that they all finish at the same time and feed their output to the
-single Combine Server in a burst, which makes less efficient use of
-the Combine Server and thus can increase the total elapsed time.
-
-<p>You may specify only one of PARALLEL_TIME_CHUNKS, PARALLEL_CHUNK_TAPER,
-and PARALLEL_PERFECT. PARALLEL_CHUNK_TAPER is usually best.
-
-<DT><b>RSH</b> <i>remote_shell_command</i>
-
-<DD><b>ppmtompeg</b> executes the shell command
-<i>remote_shell_command</i> to start a process on another machine.
-The default command is <b>rsh</b>, and whatever command you specify
-must have compatible semantics. <b>ssh</b> is usually compatible.
-The command <b>ppmtompeg</b> uses is one like this:
-<b>ssh remote.host.com -l username shellcommand</b>.
-
-<p>Be sure to set up <b>.rhosts</b> files or SSH key authorizations
-where needed. Otherwise, you'll have to type in passwords.
-
-<p>On some HP machines, <b>rsh</b> is the restricted shell, and you want
-to specify <b>remsh</b>.
-
-<DT><b>FORCE_I_ALIGN</b>
-
-<dd>This statement forces each slave to encode a chunk of frames which
-is a multiple of the pattern length (see <b>PATTERN</b>). Since the
-first frame in any pattern is an I frame, this forces each chunk
-encoded by a slave to begin with an I frame.
-
-<p>This document used to say there was an argument to
-<b>FORCE_I_ALIGN</b> which was the number of frames <b>ppmtompeg</b>
-would use (and was required to be a multiple of the pattern length).
-But <b>ppmtompeg</b> has apparently always ignored that argument, and
-it does now.
-
-<DT><B>KEEP_TEMP_FILES</B>
-
-<dd>This statement causes <b>ppmtompeg</b> not to delete the temporary
-files it uses to transmit encoded frames to the combine server. This
-means you will be left with a file for each frame, the same as you
-would get with the <b>-frames</b> option.
-
-<p>This is mostly useful for debugging.
-
-<p>This works only if you're using a shared filesystem to communicate
-between the servers.
-
-<p>This option was new in Netpbm 10.26 (January 2005).
-
-</DL>
-
-
-<H3>Parameter File Notes</h3>
-
-<P> If you use the <b>-combine_gops</b> option, then you need to specify
-only the SIZE and OUTPUT values in the parameter file. In
-addition, the parameter file may specify input GOP files in the same
-manner as normal input files -- except instead of using INPUT_DIR,
-INPUT, and END_INPUT, use GOP_INPUT_DIR, GOP_INPUT, and GOP_END_INPUT.
-If you specify no input GOP files, then <b>ppmtompeg</b> uses by default the
-output file name with suffix <b>.gop.</b><i>gop_num</i>, with <i>gop_num</i>
-starting from 0, as the input files.
-
-<p>If you use the <b>-combine_frames</b> option, then you need to
-specify only the SIZE, GOP_SIZE, and OUTPUT values in the
-parameter file. In addition, the parameter file may specify input
-frame files in the same manner as normal input files -- except instead
-of using INPUT_DIR, INPUT, and END_INPUT, use FRAME_INPUT_DIR,
-FRAME_INPUT, and FRAME_END_INPUT. If no input frame files are
-specified, then the default is to use the output file name with suffix
-<b>.frame.</b><i>frame_num</i>, with <i>frame_num</i> starting from 0,
-as the input files.
-
-<p>Any number of spaces and tabs may come between each option and value. Lines
-beginning with <b>#</b> are ignored. Any other lines are ignored except for
-those between INPUT and END_INPUT. This allows you to use the same
-parameter file for normal usage and for <b>-combine_gops</b> and
-<b>-combine_frames</b>.
-
-<P>The file format is case-sensitive so all keywords should be in
-upper case.
-
-<P>The statements may appear in any order, except that the order within
-a block statement (such as INPUT ... END INPUT) is significant.
-
-<P><b>ppmtompeg</b> is prepared to handle up to 16 B frames between
-reference frames when encoding with input from stdin. (To build a
-modified <b>ppmtompeg</b> with a higher limit, change the constant
-B_FRAME_RUN in frame.c and recompile).
-
-<H2 id="general">GENERAL USAGE INFORMATION</H2>
-
-<H3 id="qscale">Qscale</h3>
-
-<p>The quantization scale values (qscale) give a trade-off between
-quality and compression. Using different Qscale values has very little
-effect on speed. The qscale values can be set separately for I, P, and
-B frames.
-
-<p>You select the qscale values with the <B>IQSCALE</b>,
-<b>PQSCALE</b>, and <b>BSCALE</b> parameter file statements.
-
-<p>A qscale value is an integer from 1 to 31. Larger numbers give
-better compression, but worse quality. In the following, the quality
-numbers are peak signal-to-noise ratio, defined as:
-<img src="ppmtompeg-snr.gif" alt="signal-to-noise formula" height="52" width="302">
-where MSE is the mean squared error.
-
-
-<p>Flower garden tests:
-
-<table border="1" cellpadding="5" cellspacing="0" summary="Qscale vs Quality">
- <caption>Qscale vs Quality</caption>
-<?makeman r r r r. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Qscale</th>
- <th>I Frames</th>
- <th>P Frames</th>
- <th>B Frames</th>
- </tr>
- <tr>
- <td align="right">1</td>
- <td align="right">43.2</td>
- <td align="right">46.3</td>
- <td align="right">46.5</td>
- </tr>
- <tr>
- <td align="right">6</td>
- <td align="right">32.6</td>
- <td align="right">34.6</td>
- <td align="right">34.3</td>
- </tr>
- <tr>
- <td align="right">11</td>
- <td align="right">28.6</td>
- <td align="right">29.5</td>
- <td align="right">30.0</td>
- </tr>
- <tr>
- <td align="right">16</td>
- <td align="right">26.3</td>
- <td align="right">26.8</td>
- <td align="right">28.6</td>
- </tr>
- <tr>
- <td align="right">21</td>
- <td align="right">24.7</td>
- <td align="right">25.0</td>
- <td align="right">27.9</td>
- </tr>
- <tr>
- <td align="right">26</td>
- <td align="right">23.5</td>
- <td align="right">23.9</td>
- <td align="right">27.5</td>
- </tr>
- <tr>
- <td align="right">31</td>
- <td align="right">22.6</td>
- <td align="right">23.0</td>
- <td align="right">27.3</td>
- </tr>
-</table>
-
-<table border="1" cellpadding="5" cellspacing="0"
-summary="Qscale vs Compression">
- <caption>Qscale vs Compression</caption>
-<?makeman r r r r. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Qscale</th>
- <th>I Frames</th>
- <th>P Frames</th>
- <th>B Frames</th>
- </tr>
- <tr>
- <td align="right">1</td>
- <td align="right">2</td>
- <td align="right">2</td>
- <td align="right">2</td>
- </tr>
- <tr>
- <td align="right">6</td>
- <td align="right">7</td>
- <td align="right">10</td>
- <td align="right">15</td>
- </tr>
- <tr>
- <td align="right">11</td>
- <td align="right">11</td>
- <td align="right">18</td>
- <td align="right">43</td>
- </tr>
- <tr>
- <td align="right">16</td>
- <td align="right">15</td>
- <td align="right">29</td>
- <td align="right">97</td>
- </tr>
- <tr>
- <td align="right">21</td>
- <td align="right">19</td>
- <td align="right">41</td>
- <td align="right">173</td>
- </tr>
- <tr>
- <td align="right">26</td>
- <td align="right">24</td>
- <td align="right">56</td>
- <td align="right">256</td>
- </tr>
- <tr>
- <td align="right">31</td>
- <td align="right">28</td>
- <td align="right">73</td>
- <td align="right">330</td>
- </tr>
-</table>
-
-
-<h3>Search Techniques</h3>
-
-<p>There are several different motion vector search techniques
-available. There are different techniques available for P frame
-search and B frame search. Using different search techniques present
-little difference in quality, but a large difference in compression
-and speed.
-
-<p>There are 4 types of P frame search: Exhaustive, TwoLevel,
-SubSample, and Logarithmic.
-
-<p>There are 3 types of B frame search: Exhaustive, Cross2, and
-Simple.
-
-The recommended search techniques are TwoLevel and Logarithmic for
-P frame search, and Cross2 and Simple for B frame search. Here are
-some numbers comparing the different search methods:
-
-<table border="1" cellpadding="5" cellspacing="0"
-summary="P frame motion vector search">
- <caption>P frame Motion Vector Search (Normalized)</caption>
-<?makeman r c c c. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Technique</th>
- <th>Compression<a href="#smallbetter"><sup>1</sup></a></th>
- <th>Speed <a href="#largefaster"><sup>2</sup></a></th>
- <th>Quality <a href="#largebetter"><sup>3</sup></a></th>
- </tr>
- <tr>
- <td align="right">Exhaustive</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- </tr>
- <tr>
- <td align="right">SubSample</td>
- <td align="center">1008</td>
- <td align="center">2456</td>
- <td align="center">1000</td>
- </tr>
- <tr>
- <td align="right">TwoLevel</td>
- <td align="center">1009</td>
- <td align="center">3237</td>
- <td align="center">1000</td>
- </tr>
- <tr>
- <td align="right">Logarithmic</td>
- <td align="center">1085</td>
- <td align="center">8229</td>
- <td align="center">998</td>
- </tr>
-</table>
-
-<table border="1" cellpadding="5" cellspacing="0"
-summary="B frame motion vector search">
- <caption>B frame Motion Vector Search (Normalized)</caption>
-<?makeman r c c c. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Technique</th>
- <th>Compression<a href="#smallbetter"><sup>1</sup></a></th>
- <th>Speed<a href="#largefaster"><sup>2</sup></a></th>
- <th>Quality<a href="#largebetter"><sup>3</sup></a></th>
- </tr>
- <tr>
- <td align="right">Exhaustive</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- </tr>
- <tr>
- <td align="right">Cross2</td>
- <td align="center">975</td>
- <td align="center">1000</td>
- <td align="center">996</td>
- </tr>
- <tr>
- <td align="right">Simple</td>
- <td align="center">938</td>
- <td align="center">1765</td>
- <td align="center">991</td>
- </tr>
-</table>
-
-<a name="smallbetter"> </a><sup>1</sup>Smaller numbers are better
-compression.
-
-<a name="largefaster"> </a><sup>2</sup>Larger numbers mean faster
-execution.
-
-<a name="largebetter"> </a><sup>3</sup>Larger numbers mean better quality.
-
-<p>For some reason, Simple seems to give better compression, but it
-depends on the image sequence.
-
-<p>Select the search techniques with the <B>PSEARCH_ALG</B> and
-<B>BSEARCH_ALG</b> parameter file statements.
-
-
-<a name="gop"></a>
-<h3>Group Of Pictures (GOP)</h3>
-
-<p>A Group of Pictures (GOP) is a roughly independently decodable
-sequence of frames. An MPEG video stream is made of one or more
-GOP's. You may specify how many frames should be in each GOP with the
-<b>GOP_SIZE</b> parameter file statement. A GOP always starts with an
-I frame.
-
-<p>Instead of encoding an entire sequence, you can encode a single
-GOP. To do this, use the <b>-gop</b> command option. You can later
-join the resulting GOP files at any time by running <b>ppmtompeg</b>
-with the <b>-combine_gops</b> command option.
-
-
-<h3>Slices</h3>
-
-<p>A slice is an independently decodable unit in a frame. It can be
-as small as one macroblock, or it can be as big as the entire frame.
-Barring transmission error, adding slices does not change quality or
-speed; the only effect is slightly worse compression. More slices are
-used for noisy transmission so that errors are more recoverable. Since
-usually errors are not such a problem, we usually just use one slice
-per frame.
-
-<p>Control the slice size with the <B>SLICES_PER_FRAME</B> parameter
-file statement.
-
-<p>Some MPEG playback systems require that each slice consist of whole
-rows of macroblocks. If you are encoding for this kind of player, if
-the height of the image is H pixels, then you should set the
-SLICES_PER_FRAME to some number which divides H/16. For example, if
-the image is 240 pixels (15 macroblocks) high, then you should use
-only 15, 5, 3, or 1 slices per frame.
-
-<p>Note: these MPEG playback systems are really wrong, since the MPEG
-standard says this doesn't have to be so.
-
-
-
-<h3>Search Window</h3>
-
-<p>The search window is the window in which <b>ppmtompeg</b> searches
-for motion vectors. The window is a square. You can specify the size
-of the square, and whether to allow half-pixel motion vectors or not,
-with the <b>RANGE</b> and <b>PIXEL</B> parameter file statements.
-
-<h3 id="ipb">I Frames, P Frames, B Frames</h3>
-
-<p>In MPEG-1, a movie is represented as a sequence of MPEG frames,
-each of which is an I Frame, a P Frame, or a B Frame. Each represents
-an actual frame of the movie (don't get confused by the dual use of
-the word "frame." A movie frame is a graphical image. An MPEG frame
-is a set of data that describes a movie frame).
-
-<p>An I frame ("intra" frame) describes a movie frame in isolation --
-without respect to any other frame in the movie. A P frame
-("predictive" frame) describes a movie frame by describing how it
-differs from the movie frame described by the latest preceding I or
-P frame. A B frame ("bidirectional" frame) describes a movie frame by
-describing how it differs from the movie frames described by the
-nearest I or P frame before <em>and</em> after it.
-
-<p>Note that the first frame of a movie must be described by an I
-frame (because there is no previous movie frame) and the last movie
-frame must be described by an I or P frame (because there is no
-subsequent movie frame).
-
-<p>Beyond that, you can choose which frames are represented by which
-types. You specify a pattern, such as IBPBP and <b>ppmtompeg</b>
-simply repeats it over and over throughout the movie. The pattern
-affects speed, quality, and stream size. Here is a chart which shows
-some of the trade-offs:
-
-<table border="1" cellpadding="5" cellspacing="0"
-summary="Comparison of I/P/B Frames">
- <caption>Comparison of I/P/B Frames (Normalized)</caption>
-<?makeman r c c c. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Frame Type</th>
- <th>Size</th>
- <th>Speed</th>
- <th>Quality</th>
- </tr>
- <tr>
- <td align="right">I frames</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- <td align="center">1000</td>
- </tr>
- <tr>
- <td align="right">P frames</td>
- <td align="center">409</td>
- <td align="center">609</td>
- <td align="center">969</td>
- </tr>
- <tr>
- <td align="right">B frames</td>
- <td align="center">72</td>
- <td align="center">260</td>
- <td align="center">919</td>
- </tr>
- </table>
-
-(this is with constant qscale)
-
-<p>A standard sequence is IBBPBBPBBPBBPBB.
-
-<p>Select the sequence with the <B>PATTERN</B> parameter file statement.
-
-<p>Since the last MPEG frame cannot be a B frame (see above), if the
-pattern you specify indicates a B frame for the last movie frame of
-the movie, <b>ppmtompeg</b> makes it an I frame instead.
-
-<p>Before Netpbm 10.26 (January 2005), <b>ppmtompeg</b> instead drops
-the trailing B frames by default, and you need the
-<b>FORCE_ENCODE_LAST_FRAME</b> parameter file statement to make it do
-this.
-
-<p>The MPEG frames don't appear in the MPEG-1 stream in the same order that
-the corresponding movie frames appear in the movie -- the B frames come after
-the I and P frames on which they are based. For example, if the movie is
-4 frames that you will represent with the pattern IBBP, the MPEG-1 stream
-will start with an I frame describing movie frame 0. The next frame in
-the MPEG-1 stream is a P frame describing movie frame 3. The last two
-frames in the MPEG-1 stream are B frames describing movie frames 1 and 2,
-respectively.
-
-
-<h3>Specifying Input and Output Files</h3>
-
-<p>Specify the input frame images with the <B>INPUT_DIR</B>,
-<B>INPUT</B>, <B>END_INPUT</B>, <B>BASE_FILE_FORMAT</B>,
-<B>SIZE</B>, <B>YUV_FORMAT</B> and <b>INPUT_CONVERT</B> parameter
-file statements.
-
-<p>Specify the output file with the <b>OUTPUT</b> parameter file statement.
-
-
-<h3>Statistics</h3>
-
-<p><b>ppmtompeg</b> can generate a variety of statistics about the
-encoding. See the <b>-stat</b>, <b>-snr</b>, <b>-mv_histogram</b>,
-<b>-quiet</b>, <b>-no_frame_summary</b>, and <b>-bit_rate_info</b>
-options.
-
-
-<H2 id="parallel">PARALLEL OPERATION</H2>
-
-<P>You can run <b>ppmtompeg</b> on multiple machines at once, encoding
-the same MPEG stream. When you do, the machines are used as shown in
-the following diagram. We call this "parallel mode."
-
-<p><img src="ppmtompeg-par.gif" alt="ppmtompeg-par.gif">
-
-<p>To do parallel processing, put the statement
-
-<pre>
- PARALLEL
-</pre>
-
-in the parameter file, followed by a listing of the machines, one
-machine per line, then
-
-<pre>
- END_PARALLEL
-</pre>
-
-Each of the machine lines must be in one of two forms. If the machine
-has filesystem access to the input files, then the line is:
-
-<p>
-<i>machine</i> <i>user</i> <i>executable</i>
-
-<P>The executable is normally <b>ppmtompeg</b> (you may need to give
-the complete path if you've built for different architectures). If
-the machine does not have filesystem access to the input files, the line
-is:
-
-<P><b>REMOTE</b> <i>machine</i> <i>user</i> <i>executable</i>
-<i>parameter file</i>
-
-<p>The <b>-max_machines</b> command option limits the number of
-machines <b>ppmtompeg</b> will use. If you specify more machines in
-the parameter file than <b>-max_machines</b> allows, <b>ppmtompeg</b>
-uses only the machines listed first. This is handy if you want to
-experiment with different amounts of parallelism.
-
-<p>In general, you should use full path file names when describing
-executables and parameter files. This <em>includes</em> the parameter
-file argument on the original invocation of <b>ppmtompeg</b>.
-
-<p>All file names must be the same on all systems (so if e.g. you're
-using an NFS filesystem, you must make sure it is mounted at the same
-mountpoint on all systems).
-
-<P>Because not all of the processes involved in parallel operation
-have easy access to the input files, you must specify the <B>SIZE</B>
-parameter file statement when you do parallel operation.
-
-<p>The machine on which you originally invoke <b>ppmtompeg</b> is the
-master machine. It hosts a "combine server,", a
-"decode server," and a number of "i/o servers,"
-all as separate processes. The other machines in the network (listed
-in the parameter file) are slave machines. Each hosts a single
-process that continuously requests work from the master and does it.
-The slave process does the computation to encode MPEG frames. It
-processes frames in batches identified by the master.
-
-<p>The master uses a remote shell command to start a process on a
-slave machine. By default, it uses an <b>rsh</b> shell command to do
-this. But use the <b>RSH</b> parameter file statement to control
-this. The shell command the master executes remotely is
-<b>ppmtompeg</b>, but with options to indicate that it is to perform
-slave functions.
-
-<p>The various machines talk to each other over TCP connections. Each
-machine finds and binds to a free TCP port number and tells its
-partners the port number. These port numbers are at least 2048.
-
-<p>Use the PARALLEL_TEST_FRAMES, PARALLEL_TIME_CHUNKS, and
-PARALLEL_PERFECT parameter file statements to control the way the
-master divides up work among the slaves.
-
-<p>Use the <b>-nice</b> command option to cause all slave processes to run
-"nicely," i.e. as low priority processes. That way, this substantial and
-long-running CPU load will have minimal impact on other, possibly
-interactive, users of the systems.
-
-<A NAME="speed"> </A>
-<H2>SPEED</h2>
-
-<p>Here is a look at <b>ppmtompeg</b> speed, in single-node (not parallel)
-operation:
-
-<table border="1" cellpadding="5" cellspacing="0" summary="Compression speed">
- <caption>Compression Speed</caption>
-<?makeman r c. ?>
-<?makeman _ ?>
- <tr align="center">
- <th>Machine Type</th>
- <th>Macroblocks per second<sup>1</sup></th>
- </tr>
- <tr>
- <td align="right">HP 9000/755</td>
- <td align="center">280</td>
- </tr>
- <tr>
- <td align="right">DEC 3000/400</td>
- <td align="center">247</td>
- </tr>
- <tr>
- <td align="right">HP 9000/750</td>
- <td align="center">191</td>
- </tr>
- <tr>
- <td align="right">Sparc 10</td>
- <td align="center">104</td>
- </tr>
- <tr>
- <td align="right">DEC 5000</td>
- <td align="center">68</td>
- </tr>
-</table>
-<sup>1</sup>A macroblock is a 16x16 pixel square
-
-<p>The measurements in the table are with inputs and outputs via a
-conventional locally attached filesystem. If you are using a network
-filesystem over a single 10 MB/s Ethernet, that constrains your speed more
-than your CPU speed. In that case, don't expect to get better than 4
-or 5 frames per second no matter how fast your CPUs are.
-
-<p>Network speed is even more of a bottleneck when the slaves do not
-have filesystem access to the input files -- i.e. you declare them
-REMOTE.
-
-<p>Where I/O is the bottleneck, size of the input frames can make a big
-difference. So YUV input is better than PPM, and JPEG is better than
-both.
-
-<p>When you're first trying to get parallel mode working, be sure to
-use the <b>-debug_machines</b> option so you can see what's going on.
-Also, <b>-debug_sockets</b> can help you diagnose communication
-problems.
-
-
-<H2 id="authors">AUTHORS</H2>
-
-<UL>
-
-<LI>Kevin Gong - University of California, Berkeley, <A
-HREF="mailto:keving@cs.berkeley.edu">keving@cs.berkeley.edu</A>
-
-<LI>Ketan Patel - University of California, Berkeley, <A
-HREF="mailto:kpatel@cs.berkeley.edu">kpatel@cs.berkeley.edu</A>
-
-<LI>Dan Wallach - University of California, Berkeley, <A
-HREF="mailto:dwallach@cs.berkeley.edu">dwallach@cs.berkeley.edu</A>
-
-<LI>Darryl Brown - University of California, Berkeley, <A
-HREF="mailto:darryl@cs.berkeley.edu">darryl@cs.berkeley.edu</A>
-
-<LI>Eugene Hung - University of California, Berkeley, <A
-HREF="mailto:eyhung@cs.berkeley.edu">eyhung@cs.berkeley.edu</A>
-
-<LI>Steve Smoot - University of California, Berkeley, <A
-HREF="mailto:smoot@cs.berkeley.edu">smoot@cs.berkeley.edu</A>
-
-</UL>
-
-<HR>
-<A NAME="index"> </A>
-<H2>Table Of Contents</H2>
-<UL>
-<LI><A HREF="#synopsis">SYNOPSIS</A></LI>
-<LI><A HREF="#description">DESCRIPTION</A></LI>
-<LI><A HREF="#options">OPTIONS</A></LI>
-<LI><A HREF="#parmfile">PARAMETER FILE</A></LI>
-<LI><A HREF="#general">GENERAL USAGE INFORMATION</A></LI>
-<LI><A HREF="#parallel">PARALLEL OPERATION</A></LI>
-<LI><A HREF="#speed">SPEED</A></LI>
-<LI><A HREF="#authors">AUTHORS</A></LI>
-</UL>
-</BODY>
-</HTML>
|
