Printer profiles

phil/print-preflight

A PrintProfile holds what one printer asks of a file. Every argument is named and has a default that suits most offset and digital printers; a profile for a given printer sets only what differs.

use Phil\PrintPreflight\Length;
use Phil\PrintPreflight\PrintProfile;
use Phil\PrintPreflight\Size;

$booklet = new PrintProfile(
    trimSizes: [Size::a5()],
    bleed: Length::mm(3),
    safetyMargin: Length::mm(6),
    minimumPages: 8,
    maximumPages: 64,
    pageMultiple: 4,
);

Rules

Argument	Default	Rule
`trimSizes`	`[]`	The trim sizes the printer prints, each orientation it accepts listed on its own; empty for any size
`uniformTrimSize`	`true`	Every page has the trim size of the first page
`bleed`	`Length::mm(3)`	The bleed each page must carry, and how far past the trim edge an element that bleeds must reach
`safetyMargin`	`Length::mm(5)`	How far inside the trim edge content must stay
`minimumResolution`	`150`	The effective resolution, in pixels per inch, below which an image is an error
`targetResolution`	`300`	The effective resolution below which an image is a warning
`maximumResolution`	`null`	The effective resolution above which an image is a notice, as weight the printer discards; none by default
`minimumPages`	`1`	The fewest pages the printer binds
`maximumPages`	`null`	The most pages it binds; no limit by default
`pageMultiple`	`1`	The page count must be a multiple of it: 2 for a sheet printed on both sides, 4 for saddle stitching
`colourWorkflow`	`ColourWorkflow::Cmyk`	The colours the printer expects: CMYK, or RGB for services that convert themselves
`allowSpotColours`	`false`	Whether the printer runs spot colour plates
`maximumInkCoverage`	`300`	The total ink coverage, in percent, above which an image or a flat colour is an error, in a CMYK workflow: 300 suits coated paper on an offset press, 260 to 280 uncoated paper, 240 newsprint
`minimumLineWidth`	`Length::pt(0.25)`	The thinnest line the printer reproduces; a thinner one is a warning
`allowOverprint`	`true`	Whether the printer honours overprint; when it does not, every element set to overprint is a warning
`allowTransparency`	`true`	Whether the printer accepts live transparency, as PDF/X-4 does; when it does not, as with PDF/X-1a, every element that uses it is a warning
`severities`	`[]`	The severity of a rule, by its code, in place of its default
`ignore`	`[]`	The codes of the rules not to report

A profile whose rules contradict each other is refused with InvalidProfile: a negative bleed or safety margin, a minimum resolution that is not positive, a target below the minimum, a maximum below the target, a minimum page count below one, a maximum below the minimum, a page multiple below one, a maximum ink coverage that is not positive, a negative minimum line width.

Severities

Each built-in rule has a default severity (see Checks and findings). A printer that adds blank pages itself makes the multiple a warning; one that never converts colours makes RGB an error; an application that does not want notices about colour ignores them:

use Phil\PrintPreflight\PrintProfile;
use Phil\PrintPreflight\Rule;
use Phil\PrintPreflight\Severity;

$profile = new PrintProfile(
    pageMultiple: 4,
    severities: [Rule::PageCountMultiple->value => Severity::Warning, Rule::ColourRgbInCmyk->value => Severity::Error],
    ignore: [Rule::ColourSpot->value],
);

The keys are codes, not Rule cases, so a profile also sets the severity of the findings of a check the application adds.