Without the "--below" option, it is guarenteed to start at the 0,0 coordinate. "--below", "--hires" and "-v" are recommended options.
The page size is set exactly corresponding to the BoundingBox. This means that when Ghostscript renders it, the result needs no cropping, and the PDF MediaBox is correct.
If the bounding box is not right, of course, you have problems. If you feed crap in, you get crap. But you can supply the --bboxfrom=compute-gs option to make GS recompute the bounding box.
The name of the input file doesn't matter --- a2ping detects the file format based on the first few bytes of the file. The name of the output file matters if outformat is missing from the command line: then the extension of the output file determines the FileFormat (outformat).
To analyse the bounding box and other properties of non-EPS PS files (and EPS files with option --bboxfrom other than =guess), GS is used. Converting PS to EPS involves this analysis.
To write PDF files, GS is used.
To read PDF files, pdftops from the xpdf package is used.
Sampled input formats are PNG, JPEG, TIFF, PNM, BMP, GIF, LBM, XPM, PCX and TGA. To read sampled input formats, sam2p is used. sam2p is a raster image converter written in C++ by the author of a2ping.pl.
Extra output formats are PNG, XWD, BMP, TIFF, JPEG, GIF and XPM. To write extra output formats, sam2p and GS are used.
PNM output formats are PGM, PGM and PPM. To write PNM output formats, GS is used.
a2ping is inspired by and historically based on the epstopdf Perl script modified by Thomas Esser, Sept. 1998, but his modifications have been removed from a2ping, and also a2ping and epstopdf do not share common code anymore. epstopdf is written by Sebastian Rahtz, for Elsevier Science. epstopdf contained extra tricks from Hans Hagen's texutil.
1999/05/06 v2.5 (Heiko Oberdiek)
* New options: --hires, --exact, --filter, --help. * Many cosmetics: title, usage, ... * New code for debug, warning, error * Detecting of cygwin perl * Scanning for %%{Hires,Exact,}BoundingBox. * Scanning only the header in order not to get a wrong BoundingBox of an included file. * (atend) supported. * uses strict; (earlier error detecting). * changed first comment from '%!PS' to '%!'; * corrected (atend) pattern: '\s*\(atend\)' * using of $bbxpat in all BoundingBox cases, correct the first white space to '...Box:\s*$bb...' * corrected first line (one line instead of two before 'if 0;';
2000/11/05 v2.6 (Heiko Oberdiek)
* %%HiresBoundingBox corrected to %%HiResBoundingBox
2001/03/05 v2.7 (Heiko Oberdiek)
* Newline before grestore for the case that there is no whitespace at the end of the eps file.
2003/02/02 (Szab['o] P['e]ter)
* option --below * removes DOS EPSF binary junk correctly * adds all 3 BoundingBox DSC comments * reads all 3 BoundingBox DSC comments, and picks the best * forces BoundingBox to be an integer * adds %%EndComments and proper %!PS-Adobe-?-? EPSF-?.? header * adds %%Pages: * adds invocation syntax: a2ping <infile.eps> <outfile.eps|pdf> * can convert PDF to EPS (by calling pdftops(1)) and PDF to PDF * emulates work for PDF input
2003/04/16 (Szab['o] P['e]ter)
* added PS and sam2p support, renamed to a2ping * sam2p and pdftops if $InputFilename eq '-'; * remove PJL UEL header from the beginning * works for PS non-EPS files for input * input support for PNG JPEG TIFF PNM BMP GIF LBM XPM PCX TGA via sam2p * removes ^L (form feed) from end of EPS file * -x=-c:rle to add sam2p options
2003/04/26 (Szab['o] P['e]ter)
* omit the unnecessary setpagedevice calls when creating normal eps * --noverbose --nocompress supported differently * no more option defaults :-( * justlib2 * multi-page output with PS:, PDF:, PCL5: * after `a2ping -pa4', file out.pcl says: `HP PCL printer data - A4 page size', instead of `US letter' * justlib2-ified doesn't depend on Getopt::Long anymore * fully supports filtering (stdin and/or stdout), PDF and PCL5 output to pipe (!$$ll_zero) * adds DSC ``%%DocumentMedia: plain 612 792 0 () ()'' * BoundingBox precedence for EPS input: --PageSize, %%*BoundingBox, setpagedevice. Precedence for other inputs: --PageSize, setpagedevice, %%*BoundingBox
2003/09/25 (Szab['o] P['e]ter)
* --bboxfrom=adsc: %%BoundingBox overrides -sDEVICE=bbox * improved bbox discovery * many bugfixes * MetaPost EPS input fixes for prologues:=0; * a2ping.pl -v --papersize=50,60 --bboxfrom=compute-gs t.ps t2.ps * consistent bbox, --PageSize, /PageSize handling * consistent --Resolution and --Duplex handling
2003/12/02 (Szab['o] P['e]ter)
* --bboxfrom=compute-gs option to fix PS -> EPS bbox (gs -sDEVICE=bbox), tuzv.eps
2004/02/10 v2.77 (Szab['o] P['e]ter)
* the compute-pipe routine is now run unless --bboxfrom=guess with EPS * added --gsextra= * added --antialias= * added FileFormat PBM, PGM, PPM * separated FileFormat features to FL_* constants * added --doc * there is no default FileFormat (PDF) anymore