dvips produces improperly-trimmed output for non-standard papersize

Question

Note:

Rather than creating a new question that has almost the same code base, I rewrote my previous question. Because this issue is not specific to PSTricks, I changed the code so everybody can play with it.

---

I want to avoid using pdfcrop so I set the paper size to tightly suit my need in advance as follows.

% sample.tex
\documentclass{minimal}
\usepackage
[
paperwidth=144bp,%2in = 2x72bp = 144bp
paperheight=108bp,%1.5in = 1.5x72bp = 108bp
margin=0bp
]
{geometry}
\usepackage{xcolor,calc}
\fboxsep=0bp
\fboxrule=2bp
\begin{document}
\noindent\fbox{\color{yellow}\rule{\paperwidth-2\fboxrule}{\paperheight-2\fboxrule}}%
\end{document}

or without using geometry.sty:

% sample.tex
\documentclass{minimal}
\paperwidth=144bp%2in = 2x72bp = 144bp
\paperheight=108bp%1.5in = 1.5x72bp = 108bp
\voffset=-72bp
\hoffset=-72bp
\special{papersize=144bp,108bp}
\usepackage{xcolor,calc}
\fboxsep=0bp
\fboxrule=2bp
\begin{document}
\noindent\fbox{\color{yellow}\rule{\paperwidth-2\fboxrule}{\paperheight-2\fboxrule}}%
\end{document}

Then I compiled it with latex->dvips->ps2pdf and I got a strange result as follows:

I also got EPS with strange bounding box as follows:

%!PS-Adobe-3.0 EPSF-3.0
% Produced by xpdf/pdftops 3.02pl4
%%Creator: TeX
%%LanguageLevel: 2
%%DocumentSuppliedResources: (atend)
%%BoundingBox: 0 0 105 145
%%HiResBoundingBox: 0 0 104.994 144.018
%%EndComments
%%BeginProlog
%%BeginResource: procset xpdf 3.02pl4 0
%%Copyright: Copyright 1996-2007 Glyph & Cog, LLC

Summary

I tested this using pdflatex with no problem. Herbert tested it using xelatex with no problem too. According to Herbert, there is a problem in dvips.

Answer 1

As Ulrike mentions in a comment, dvips tries a known paper size that is near the specified dimensions. The call

dvips -t unknown sample -o

produces the following header:

%!PS-Adobe-2.0
%%Creator: dvips(k) 5.99 Copyright 2010 Radical Eye Software
%%Title: sample.dvi
%%CreationDate: Sun Jul 10 19:22:45 2011
%%Pages: 1
%%PageOrder: Ascend
%%BoundingBox: 0 0 144 108
%%EndComments
%DVIPSWebPage: (www.radicaleye.com)
%DVIPSCommandLine: dvips -t unknown sample -o
%DVIPSParameters: dpi=600
%DVIPSSource:  TeX output 2011.07.10:1911
%%BeginProcSet: tex.pro 0 0
%!

to be compared with the code obtained without -t unknown:

%!PS-Adobe-2.0
%%Creator: dvips(k) 5.99 Copyright 2010 Radical Eye Software
%%Title: sample.dvi
%%CreationDate: Sun Jul 10 19:19:40 2011
%%Pages: 1
%%PageOrder: Ascend
%%Orientation: Landscape
%%BoundingBox: 0 0 105 148
%%DocumentPaperSizes: a9
%%EndComments
%DVIPSWebPage: (www.radicaleye.com)
%DVIPSCommandLine: dvips sample -o
%DVIPSParameters: dpi=600
%DVIPSSource:  TeX output 2011.07.10:1911
%%BeginProcSet: tex.pro 0 0
%!