Hide the human readable text under a printed barcode

The line of digits under every barcode is for people, and it costs you a full row of label height on every code. On multi-row sheets — pick lists, work orders, tray labels — deleting that row packs more codes onto each page and often onto each label. Because a reader decodes the bars and spaces and never the digits, the change is free at the scanner as long as the quiet zone survives your tighter layout. This guide shows which property turns the text off, how to render the symbol yourself when no property exists, the quiet-zone widths to hold, and the pixel math that proves your camera still reads the result.

Does the scanner ever read the digits under the barcode?

No — a decoder measures the widths of the bars and spaces against the symbol's start and stop pattern, and the digits printed underneath never enter that calculation. GS1's name for those digits is the human readable interpretation, HRI. The symbology standards define the machine pattern and treat the interpretation as a separate, optional layer, so a text-free symbol decodes to exactly the same characters as before on a handheld gun, a fixed reader or a camera.

What the reader does care about is untouched by your edit: module width, contrast and reading geometry — the factors behind Code 128 module size, reading angle and reader distance. Dropping the text is a people decision, not a scanning decision.

Are you allowed to print a barcode with no text under it?

On internal labels that only machines scan, yes: no symbology standard makes the interpretation part of the symbol, so a text-free Code 39, Code 128 or QR print is a compliant print. Two rule sets override that freedom. GS1 labeling for retail and healthcare requires the HRI in defined positions, so an EAN-13 on a selling unit keeps its digits. ISO 22742, which governs coding on healthcare packaging, requires the human readable interpretation for linear symbols.

The third force is your own recovery path. When a read fails and an operator keys the number by hand, the text is the fallback; delete it and a ten-second recovery becomes a stopped line. Decision: internal, machine-only tracking — drop the text and take the row back. Customer-facing, regulated, or human-fallback labels — keep it.

How do you stop the barcode component from drawing the text?

Look for a visibility property on the component — display components commonly name it showText — and clear it; when the report engine exposes no toggle, render the symbol yourself and leave out the text-drawing call. Some report components gained the toggle only in a later release of their suite, so an older build can simply lack it.

1. Search the component's property list for a text switch: showText, "display value", "human readable". If one exists, set it off and jump to step 5.
2. If none exists, build the bar and space widths from your symbology's pattern table and draw them as rectangles. The Code 39 printing walkthrough and the EAN-13 bitmap walkthrough cover the pattern-to-rectangle steps; both finish with a text-drawing call, and that is the call you omit.
3. Change nothing else: same X-dimension, same bar height, same quiet zone. The missing text row is the only edit.
4. Spend the freed height so no neighbour's print moves into the quiet zone — the widths are in the next section.
5. Print one page and read every symbol with the production reader before releasing the layout.

How wide must the quiet zone be once the text is gone?

Ten times the narrow element width on each side for Code 39 and Code 128 — at a 0.33 mm X-dimension that is 3.3 mm of clear space left and right, and it does not shrink because the text left. The text never counted toward this margin; it sat below the bars, so you neither gain quiet zone nor owe any back.

EAN-13 is asymmetric under ISO/IEC 15420: 11X clear before the leading guard bar and 7X after the trailing one — 3.6 mm and 2.3 mm at the same 0.33 mm. QR needs four modules of clear margin on all four sides under ISO/IEC 18004. The risk your edit introduces is tighter rows: the symbol below moves up until its edge sits inside your quiet zone, and a code that scanned for months starts failing at its ends. The EAN-13 quiet zone failure guide walks through that diagnosis.

How much label height does removing the text actually save?

One text row per code: 8 pt digits plus their gap come to about 3.5 mm, so a sheet of 45 rows reclaims 45 × 3.5 = 157.5 mm — more than half of the 297 mm height of an A4 page. The arithmetic:

• 1 pt = 25.4 mm ÷ 72 = 0.353 mm, so an 8 pt digit row occupies 8 × 0.353 = 2.8 mm
• add the 0.7 mm gap below the bars: 2.8 + 0.7 ≈ 3.5 mm per row
• 45 rows × 3.5 mm = 157.5 mm, which is 157.5 ÷ 297 = 53% of the page height
• on a 12 mm label, the same 3.5 mm is 29% of the face

That second column on the label, or those extra rows per sheet, is the whole business case for the change.

Will a camera still read the text-free symbol at your distance?

Yes, provided the narrow element still covers at least three pixels on the sensor — the digits never entered this calculation, so the check is the one you ran before the edit: horizontal pixels against field of view. Three pixels per narrow element is the working floor and five is comfortable. Work a 300 mm strip of labels printed at X = 0.33 mm:

• modules across the strip: 300 mm ÷ 0.33 mm = 909
• pixels needed at the floor: 909 × 3 = 2727 px

A 5 MP camera in 4:3 carries about 2592 × 1944 px. Over 300 mm that is 2592 ÷ 300 = 8.64 px/mm, and 8.64 × 0.33 = 2.85 px per narrow element — under the floor. Either narrow the field of view to 2592 × 0.33 ÷ 3 = 285 mm, or step up to 6 MP, about 3072 × 2048 px: 3072 ÷ 300 = 10.24 px/mm, and 10.24 × 0.33 = 3.4 px per module, a 12% margin, with a strip ceiling of 3072 × 0.33 ÷ 3 ≈ 338 mm at the floor. Run your own strip width and X through the camera resolution calculator.

The lens follows from the field of view. A 1/2.4-inch sensor class runs about 5.8 mm across — an estimate, since formats drift a few tenths — so imaging 300 mm onto 5.8 mm is a magnification of 5.8 ÷ 300 = 0.0193.

Rearranged for working distance with an 8 mm lens: WD = 8 mm × 1.0193 ÷ 0.0193 ≈ 422 mm, so mount near 420 mm and trim focus. The MV-SC5060XM-08M-WBN is a 6 MP mono smart camera with an 8 mm focal length, an M12 mount, a 1/2.4" sensor format and a GigE interface.

For one label at a time, 1.6 MP holds the floor across a useful span: 1440 px × 0.33 mm ÷ 3 = 158 mm of maximum field of view. The MV-SCB007EC-12S-WBN is a 1.6 MP vision sensor with a 12 mm lens, manual focus, an M12 mount, a 1/2.9" sensor, a global shutter and a Fast Ethernet interface.

If the labels move, cap exposure so blur stays under half a module: at 0.5 m/s and X = 0.33 mm, t ≤ 0.5 × 0.33 mm ÷ 500 mm/s = 0.00033 s ≈ 0.3 ms. That means a strobed light, not a long integration.

What checks does a text-free label need before the print run?

Five checks on the first sheet off the press: quiet zone at final geometry, whole-dot module edges, a scan test at production distance, glare on the label stock, and your fallback if a read fails. Each one catches the specific failure that removing the text invites.

• Quiet zone at final geometry. Re-measure the quiet zone on the final artwork, after the rows moved up; the neighbour below is now the margin.
• Whole-dot modules. X must land on an integer number of printer dots — at 8 dots/mm that is 0.25 or 0.375 mm — because fractional dots print ragged edges.
• Scan test. Read twenty labels from the new layout with the production reader at the real distance and angle, corner rows included.
• Glare. Glossy stock under a bare bar light can wash out the narrow elements. A diffuser plate flattens the hot spot; the LS-LAC-0010 is a 170 x 30 mm bar light diffuser plate. Browse lighting accessories or the lighting accessories finder, and for deeper contrast problems start from improving decode on damaged, low-contrast codes.
• Fallback. Decide now what an operator does when a read fails. If the answer is "key the digits", that label family keeps its text.

When is hiding the text the wrong move?

Keep the digits when a person must key the code after a failed scan, when a GS1 retail or healthcare label requires the interpretation in its defined position, and when your camera already sits at three pixels per module with no margin. The first two are rules about people. The third is physics: deleting the text buys vertical space, never pixels, so a thin margin calls for a smaller field of view before it calls for a layout change.

Motion closes the list. The 6 MP camera above carries a rolling shutter, which shears symbols on a moving web; it belongs on stationary sheets and triggered captures. For the belt, choose a global-shutter reader — the 1.6 MP unit above has one — and strobe the light.

To pick the reader, start from the smart cameras category or the camera finder, feed the system configurator your strip width and X-dimension, or send a sample label through the contact page.