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In-Line Machine Vision Reject Archives

By Noah Loul · Reviewed by Noah Loul · Updated

  1. 01Your data spec
  2. 02Matched to businesses
  3. 03Rights and samples reviewed
  4. 04Licensed delivery
How it works with SourceX: Your data spec → Matched to businesses → Rights and samples reviewed → Licensed delivery.Illustrative

Short answer

An in-line machine vision archive holds images captured at inspection stations, either of every part or only of rejects, with the system's pass or fail call, scores and recipe settings. It is often the largest existing source of defect imagery in a plant. Retention is short, labels are the machine's own, reject folders include false alarms, and escapes are missing, so request an archive profile and a verified sample first.

What these archives are

Automated optical inspection and machine-vision stations capture an image at a trigger, run a program (a recipe) and log a verdict. What gets saved is a storage policy, and the policy decides what the archive can teach.

Storage policyWhat is keptGood forBlind spot
Store allEvery inspected partNominal and defect imagery; escapes can be found laterVolume forces short retention
Store rejects onlyParts the system flaggedDefect examples, and false alarmsNo nominal images; parts it missed are absent
Store on eventImages around alarms, faults or recipe changesDebugging contextNot representative of production
SampledEvery nth part or a periodic burstA cheap nominal baselineDefects are under-represented

Plants can mix policies across stations and change them over time, so a single archive may hold several regimes.

What a reject folder contains

A reject folder is the reverse of a curated benchmark. MVTec AD's training set, 3,629 of its 5,354 images, is defect-free only, and its test anomalies carry pixel-precise ground truth (Bergmann et al., 2021). A reject archive is defect-heavy by selection, and its labels are the machine's. Expect a mix of:

  • true defects of the types the recipe was built to find;
  • false rejects caused by dust, flicker, misalignment, a new material lot or a drifted threshold;
  • setup, calibration and test images saved under the same folder;
  • images from several recipes or product variants with no label saying which;
  • duplicates from re-presentation of the same part;
  • no examples of defects the system missed.

The last point matters most for training. The archive records what the system saw and flagged, so it inherits that system's blind spots. Reject precision, meaning the share of machine rejects that experts confirm as real defects, is the number to measure. Inspection images linked to outcomes covers attaching final decisions that settle which rejects were real.

A public example of a labeled AOI-style set

DeepPCB consists of 1,500 image pairs, each a template image and a test image, annotated with six common PCB defect types (Tang et al., 2019). Use it as a yardstick for any offer. Does the archive keep the reference image for each recipe? Are defects labeled by type and location, or only by verdict? For electronics specifically, see PCB and solder joint inspection and golden samples and reference images.

Image fidelity: what to check in the files

  • Resolution and bit depth. Ask whether files are the sensor's original size or downscaled. Small defects in large images are one of the harder cases added in MVTec AD 2 (Heckler-Kram et al., 2025), and a downscaled archive can erase them.
  • Compression. Lossy compression can smear fine defects or add artifacts that look like them. Ask for originals or lossless files where they exist.
  • Burned-in overlays. Some systems save the region of interest, verdict text or defect boxes into the pixels. A model can learn the overlay. Ask for a clean image with the result stored separately.
  • Crops versus full frames. Region crops drop the context that tells a defect from a feature.
  • Multi-view sets. Several cameras may image one part. Ask whether images are grouped by part.
  • Lighting and trigger conditions. Record lighting setup, exposure and trigger timing per image; the fields are listed in imaging conditions metadata.

Illustrative archive profile to request before any images

# Illustrative only — synthetic stations and values; the supplier completes one block per station
station: aoi_station_04
product_family: stamped_bracket_family_A
storage_policy: rejects_only             # all | rejects_only | on_event | sampled
retention: {oldest_image: 2026-06-14, rule: "overwrite at 120 days"}
counts: {total_images: "supplier-reported", rejects: "supplier-reported", passes_kept: 0}
images: {resolution: "12 MP, original", bit_depth: 8, format: png, overlays_burned_in: false}
recipes: {versions_in_period: 7, changes: ["2026-07-02 threshold", "2026-08-19 lighting"]}
hardware_changes: [{date: 2026-08-19, change: "ring light replaced"}]
identifiers: {serial_read_rate: "supplier-reported", lot_in_filename: true}
result_data: {verdict: yes, score: yes, defect_boxes: yes, reference_image_per_recipe: yes}
export: {native_format: "vendor database + image folders", vendor_support_needed: "to be confirmed"}
ownership: {images: plant, software: vision_vendor_X, customer_design: yes}

Export and format problems

Vision systems often keep metadata in a database and pixels in folders, with filenames encoding parts of the story. Extraction can need the system vendor's help, and the supplier's license for the vision software may govern what can be exported. Volumes can reach terabytes, so transfer and storage planning matter; see delivery and transfer of large datasets. Ask for a pilot export of one day's images with metadata and check it end to end before negotiating the whole archive.

Supplier types

SupplierTypical archiveStrengthWatch for
Manufacturers with AOI linesReject or all-part images per stationLarge volumes, consistent framingShort retention; recipes tied to the product
Packaging and label linesPrint, seal and fill-check imagesHigh image volumesBrand artwork and customer labels in frame
Contract manufacturersImages of customers' partsVariety of productsDesigns belong to the customers; see contract manufacturers as suppliers
Machine-vision integratorsCustomer systems they serviceTechnical knowledge of the archiveOften do not own the images

Preparation to budget for

Expect expert review to separate real defects from false rejects, de-duplication by part, relabeling into your taxonomy, joins to dispositions, and splits by lot, line and date. A pass over a random sample of rejects before purchase gives you a reject-precision estimate, which sets how much review the full archive needs.

Quality and acceptance criteria

  1. The archive profile is delivered per station and matches the sample.
  2. Reject precision is measured on a sample you draw, not one the supplier selects.
  3. Images are at original resolution and bit depth, with overlays absent or separable.
  4. Counts per recipe and per camera are given with change dates.
  5. The serial or lot join rate is stated, and unmatched images are described.
  6. Nominal images are included, or the sampling rule is documented.
  7. Timestamps are in one time zone, with clock offsets noted.
  8. Duplicates and re-presentations are flagged.

What this data cannot support

Archive images do not show how a humanoid would handle, turn or present a part. They come from fixed cameras with lighting tuned for the line, not from a robot's head or wrist view, so plan separate robot-view images; see active inspection by humanoids. They do not show defects the system missed, and the machine's verdict is not ground truth. A model fitted to one line's recipe and lighting often degrades on the next (domain shift across lines).

Rights and confidentiality

Images often show part markings, serial numbers, logos and customer-owned designs, and occasionally people or screens at the edge of the frame. The plant may not own the images outright if a customer, a contract or the vision vendor claims them. Treat this as an early diligence item; confidentiality in defect data lists the questions. Cropping a design out of an image does not by itself settle whether the images may be licensed.

Questions to ask suppliers

  1. Which stations save images, and under which policy: all parts, rejects, events or samples?
  2. How long are images retained, and what is the oldest image today?
  3. How many images exist per recipe and per camera, and when did recipes, cameras or lighting change?
  4. What share of rejects do your inspectors confirm as real defects?
  5. Are images saved at original resolution without lossy compression or burned-in overlays?
  6. Can images be exported in a standard format with metadata, and what vendor support is needed?
  7. Are passing images kept, and if so, sampled how?
  8. Who owns the saved images: you, your customer or the vision-system vendor?

Discuss your requirements

If you need machine-vision images for a specific part family, describe the parts, defect types and station details to SourceX. SourceX looks for US businesses that hold suitable inspection data, checks the data and the supplier's licensing permissions, and coordinates pricing, allowed uses and delivery in a license. SourceX's role is sourcing, rights review, licensing and delivery coordination; it can also arrange annotation, scoped case by case. SourceX reviews each request and follows up about potential sources; a request does not guarantee a match.

See also the inspection, defect and failure hub, the humanoid training data guide, the guide to sourcing defect image datasets, and the catalog page on licensing images and inspection photos.

Explore sourcing and licensing options with SourceX

Sources

Frequently asked questions

What do in-line machine vision archives hold, and how does storage policy shape them?

An archive holds station images with the system's pass or fail call, scores and recipe settings, kept for every part, for rejects only, on events or as a sample. The storage policy decides what the archive can teach, since reject-only storage has no nominal images and no parts the system missed.

What do reject folders typically contain that a buyer must account for?

They mix true defects with false rejects caused by dust, flicker, misalignment or a drifted threshold, plus setup and test images, images from several recipes with no label, and duplicates from re-presentation. They contain no examples of defects the system missed.

Why should reject precision be measured on a sample the buyer draws?

Reject precision, the share of machine rejects that experts confirm as real defects, is the number to measure. A sample the buyer draws avoids selection by the supplier, and a pilot export of one day's images should be checked end to end before the whole archive is negotiated.

Describe the data your robots need

Describe the tasks, modalities and permitted uses you need. SourceX reviews the requirement and follows up about potential sources; a request does not guarantee a match.

Discuss your humanoid training-data requirements with SourceX
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