How we got here

Thumbnails and our subconscious mind.

A curiosity about mindless scrolling became a measurement project, a failed performance predictor, a human-choice study, and finally a more honest way to review what an image is asking the eye to do.

01

Our why

Why spend hours on an image that search cannot read like a title?

Creators polish thumbnails because the feed is a visual contest. A viewer can react to a face, color, object, or unresolved moment before they finish reading. We wanted to know what makes that visual hook work, and whether it leaves a measurable trace in video performance.

What gets noticed?
What gets chosen?
What performs?

“Notice,” “choose,” and “perform” sound similar. The project taught us that they are three different research questions.

02

Data collection

We started with public YouTube evidence.

We collected long-form video metadata and downloaded thumbnail images across categories. For performance analysis, views were adjusted for video age and compared only within the same channel. This reduced audience-size differences, but it could not reveal private click-through rate.

Public APIcategory, channel, title, views, date
42,488 imagescached at a consistent thumbnail size
Within-channel targetage-adjusted views above or below history
What public data gives usViews, not impressions or CTR

Views are downstream of recommendation exposure, topic, timing, audience, title, and the thumbnail. They are a noisy proxy for the click itself.

03

Reading the research

We translated design and psychology into seven visible checks.

We reviewed visual-attention research, Gestalt principles, processing fluency, thumbnail studies, and practitioner guidance. Then we turned recurring ideas into a fixed rubric that could be inspected rather than treated as intuition.

The seven-check rubricWeights are declared, not learned from performance.
  1. 01Readable on a phone20%
  2. 02Clear visual hierarchy15%
  3. 03Subject separation15%
  4. 04Controlled clutter15%
  5. 05Picture adds to title20%
  6. 06Specific visual hook10%
  7. 07Category fit5%
04

The unlabeled pass

First, we tried reading the pixels without asking people.

This was not truly unsupervised training. It was a label-free measurement system: fixed computer-vision and semantic models measured the image, then reference percentiles described how typical or strong each trait looked.

01Spectral-residual saliency

Where contrast concentrates and how many focal regions compete.

02Text and face detection

PPOCR-style text regions, YuNet face boxes, and timestamp collisions.

03CLIP and OCR meaning

Image-title alignment, visual-hook prompts, visible words, and duplication.

04Reference percentiles

Compare the measurements with similar thumbnails, then apply the fixed rubric.

This route can describe a thumbnail. Without an outcome label, it cannot learn what people click or what performs.

05

The supervised performance model

Then we gave the model an outcome and a gate.

Logistic regression and a small LightGBM model learned from image and title measurements. Training used five channel-grouped folds, so one creator could not appear in both train and test data. The question was whether the model could order better and worse videos within the same channel.

The line we promised not to moveMacro channel AUC, where 0.50 is chance and 1.00 is perfect ordering.

The signal was real, but too weak to tell a creator which thumbnail would perform better. We kept the measurement work and dropped the prediction claim.

Primary modelLogistic regressionC = 0.25, LBFGS, 2,000 max iterations
Nonlinear checkLightGBM180 trees, 7 leaves, depth 3
ValidationGroupKFold5 folds grouped by channel
06

The choice study

Views were not enough, so we asked for the first choice directly.

We built a second app that shows randomized thumbnail grids on mobile and desktop. A tap labels the chosen image and preserves the alternatives it competed against. The attention model controls for category and screen position, then learns a separate choice pattern for each device.

One promptChoose the first thumbnail that pulls your attention.
first choice

Every selected image became one label. Every other image shown in that same grid became an observed alternative.

Mobile protocol2 × 5 gridone choice among 10
Desktop protocol5 × 4 gridone choice among 20
Training unitComplete choice setselected image plus every shown alternative
07

The current model

One shared representation, two supervised questions.

We combined frozen image and title meaning with visible structure. A small neural network learns an official YouTube category and a continuous channel-relative performance target at the same time. The category task works as useful semantic supervision. The performance task remains weak.

A small shared model with two questionsAll preprocessing is fitted inside each training fold.
Image meaning512 CLIP valuescompressed to 32
Title meaning512 CLIP valuescompressed to 32
Visible structure35 measurementssaliency, text, faces, color, title
96 hidden units48-unit shared bottleneck20% dropout
Category headWhat kind of video is this?class-weighted cross-entropy
Performance headHow far above channel history?Huber regression
Evaluation
5 channel-grouped folds
Repeats
3 random seeds
Training
25 epochs, batch 512
Learning rate
0.001
Category53.5% exact74.8% top two, macro F1 0.564
Performance regressionR² 0.00353.3% within-channel pair ordering
First-look attentionsmall liftmobile clearer than desktop after position control
08

How the app works

The report turns every model into something you can inspect.

Eyelicium keeps feed context, attention, design measurements, category language, and channel familiarity separate. It does not collapse them into a single claim about future clicks.

  1. 01Upload

    Add the final crop, title, and category.

  2. 02Place

    See it inside desktop and mobile feed mockups.

  3. 03Inspect

    Read saliency, subject, text, face, and safe-area marks.

  4. 04Revise

    Use the strongest and weakest checks as the next edit.

Review a thumbnail
09

What comes next

The missing outcome is creator-owned CTR.

We can improve the attention sample, test stronger device-specific features, and validate category priming. The biggest step is simpler: compare thumbnail measurements with real impressions, click-through rate, and YouTube Test & Compare results.

More balanced first-choice dataCreator-owned CTR and impression logsReplication on fresh thumbnail setsCategory-priming experiments

Have creator-side data or want to volunteer for the next study? We will keep shared data scoped, anonymized, and clearly separated from public results.

jpaul.fernandez18@gmail.com