Barcode color screening

What the checker evaluates

The tool takes bar color, background color, and a transparent or metallic substrate answer. Bar options are Black, Dark blue, Dark green, Dark brown, Red, Orange, and Yellow. Background options are White, Yellow, Red, Blue, Green, and Black. The substrate answer is Yes or No. The checker does not accept RGB values, spectral data, measured reflectance, dimensions, or quiet zone measurements. It returns two rows, Color screen and Reason, as an early named-color screen.

How bar color is screened

The bar branch flags Red, Orange, and Yellow. Any of those selections sets Color screen to Change the color combination before proofing, whatever the background. Reason then reads Warm-colored bars can reflect scanner red light. Black, Dark blue, Dark green, and Dark brown do not trigger this branch. A red bar can look distinct on screen yet remain a poor candidate under red scanner illumination. The checker does not calculate a contrast ratio or predict scanner performance.

How background color is screened

The background branch flags Blue, Green, and Black. If the bar is not already flagged and the background is one of those three, Color screen becomes Change the color combination before proofing. Reason reads Dark background can erase symbol contrast. White, Yellow, and Red backgrounds do not trigger this branch. A dark background can reduce separation between bars and spaces, so the checker asks for a combination change before proofing. This is still a named-color screen, not a measured result.

Transparent or metallic substrate

The substrate question is evaluated only after the color branches. If either color branch is flagged, Color screen already says Change the color combination before proofing, and the substrate answer does not alter that row or the reason. If neither color branch is flagged and the substrate is Yes, Color screen becomes Require an opaque background and printed verification. If neither branch is flagged and the substrate is No, Color screen becomes Candidate for printed verification. This ordering prevents a clear or metallic answer from masking a flagged color combination.

Reading the two output rows

Color screen is the action result: change the combination before proofing, require an opaque background and printed verification, or treat the named combination as a candidate for printed verification. Reason reports the first flagged color branch. When neither color is flagged, it says named colors cannot establish measured reflectance, regardless of the substrate answer. Because the bar check runs before the background check, a combination with both a warm bar and a dark background reports the warm-bar reason. The reason row is not an exhaustive list of every concern.

Worked examples

With Black bars, White background, and No for transparent or metallic stock, neither color branch is flagged. The substrate branch is not triggered because the answer is No. Color screen reads Candidate for printed verification. Reason reads Named colors cannot establish measured reflectance. This is the supplied starting scenario. It means the names pass this screen, not that a printed symbol is verified.

With Red bars, White background, and No for transparent or metallic stock, the bar branch is flagged. Color screen reads Change the color combination before proofing. Reason reads Warm-colored bars can reflect scanner red light. The white background does not rescue the result because the bar branch is evaluated first. Changing the bar to Black, Dark blue, Dark green, or Dark brown removes this flag, after which the background and substrate branches determine the next result.

Limits and verification

A screen name or RGB value is not a barcode grade. The checker cannot establish measured reflectance, print gain, bar width, quiet zones, or symbol dimensions. Verify finished symbols under the applicable GS1 and ISO/IEC specification, including quiet zones and dimensions. The supplied GS1 Canada design guidance supports barcode color, substrate, and verification considerations, but this checker does not reproduce a full verification procedure. Candidate for printed verification is a prompt to test a printed sample, not an approval or certification.

Practical workflow

Start with the intended bar and background names, then answer the substrate question. If the result says Change the color combination before proofing, revise the flagged color before producing a proof. If it says Require an opaque background and printed verification, plan an opaque backing and a printed check. If it says Candidate for printed verification, proceed to a printed sample and verify the finished symbol under the applicable specification. Record the selected names and returned rows so the design decision is traceable.

Questions about barcode color screening