Curt wrote: > On 2023-03-12, Dan Ritter <d...@randomstring.org> wrote: > >> > > >> > Many (most?) printers do not understand PostScript. The > >> > printing system itself is based on processing PDFs. > >> > > >> > >> Oh. > >> Times have changed! > >> I thought it was the other way around. > > > > You are correct, Yassine. > > > > PostScript is an interpreted language. PDF is a compressed > > archive data format which includes simplified PostScript commands, > > images, fonts, and other chunks of data. > > > > Apart from Windows-derived GDI printers, the majority of laser > > and inkjet printers have a PostScript interpreter built in, even > > if its primary use is in interpreting PDF files. > > > > https://en.wikipedia.org/wiki/PostScript > > However, the cost of implementation was high; computers output raw PS code > that > would be interpreted by the printer into a raster image at the printer's > natural resolution. This required high performance microprocessors and ample > memory. The LaserWriter used a 12 MHz Motorola 68000, making it faster than > any > of the Macintosh computers to which it attached. When the laser printer > engines > themselves cost over a thousand dollars the added cost of PS was marginal. > But > as printer mechanisms fell in price, the cost of implementing PS became too > great a fraction of overall printer cost
As processor prices fell, this turned around. The ARM or MIPS processor and RAM inside a $100 laser printer is a tiny fraction of the cost, and completely capable of running PostScript. Now, the licensing cost from Adobe for PostScript is terribly high, but open source rode to the rescue: most printers say "PS compatible" rather than PostScript(tm). They tend to run Linux and GhostScript -- here's the Debian package description: Description: interpreter for the PostScript language and for PDF GPL Ghostscript is used for PostScript/PDF preview and printing. Usually as a back-end to a program such as ghostview, it can display PostScript and PDF documents in an X11 environment. Furthermore, it can render PostScript and PDF files as graphics to be printed on non-PostScript printers. Supported printers include common dot-matrix, inkjet and laser models. > ; in addition, with desktop computers > becoming more powerful, it no longer made sense to offload the rasterization > work onto the resource-constrained printer This is called the cycle of reincarnation: it happens over and over again, with functions being implemented in separate devices, then being integrated into a motherboard or SOC or chipset or even the CPU itself, and then occasionally coming back out for improved performance, which may then be re-integrated... -dsr-
