Less visual clutter
Only the arm relevant to the accepted issue is emphasized instead of covering the player with a full-body skeleton.
Visual pose correction
Visual tennis pose correction should clarify the evidence—not cover it.
ACEAI can draw a compact target for the hitting arm at the relevant video moment. The guide appears only after pose quality, racket hand, issue timing, and target confidence agree.
The overlay is a directional coaching reference, not a measured prescription for every joint.
Confidence-gated guideEvidence review
Hitting-arm target · evidence frame 04
01
White lineDetected shoulder-to-wrist structure in this frame.
02
Green lineSuggested direction for the accepted correction.
03
Hidden stateNo guide when evidence checks do not agree.
Racket-hand awareness
The correction must match the detected or manually confirmed hitting side before it can be drawn.
Playback-linked timing
The guide is associated with a specific issue window and can appear during playback near that evidence moment.
A transparent workflow
From court footage to a focused next step
ACEAI separates observable evidence from coaching interpretation so you can understand where each suggestion comes from.
- 1
Detect a usable pose
Local pose landmarks must show the relevant shoulder, elbow, and wrist with sufficient visibility.
- 2
Ground the issue
The coaching observation needs a timestamp, target arm, correction direction, and supporting evidence.
- 3
Check consistency
Nearby frames help reject unstable arm-landmark estimates before a target is retained.
- 4
Draw or stay silent
A solid or reference guide is shown when checks pass; otherwise the overlay remains hidden.
Reading the overlay
The detected arm and the suggested arm are different layers
The neutral arm line represents the current shoulder, elbow, and wrist detected in the video frame. The green target represents a coaching direction linked to the accepted issue. Seeing both helps the player compare where the arm is and the direction it could move, without drawing every landmark on screen.
The target is intentionally compact. It does not claim to recover the exact three-dimensional racket path from a two-dimensional phone video. Depth is flattened by the camera, the racket can blur, and clothing or the body may hide a joint. Use the guide as a directional cue alongside the written evidence.
Solid target
The clearest presentation, reserved for frames where pose and correction evidence are strong.
Reference guide
A more cautious presentation that communicates direction without implying exact coordinates.
No target
The correct state when the relevant arm, timing, or correction cannot be supported.
Arrow cue
Shows the direction from the detected wrist toward the accepted target position.
Why confidence matters
A plausible-looking skeleton can still be wrong
Pose models estimate body landmarks from pixels. They can swap sides when a player turns, lose the wrist behind the torso, follow the non-racket arm, or become unstable during motion blur. A visually polished line does not make those estimates reliable.
ACEAI combines several checks before drawing: the analysis must be confident in the issue, the racket hand must be known, the target must belong to that hand, important joints must be visible, the video must be near the evidence timestamp, and the pose must remain stable. This conservative policy means some useful written observations will have no visual correction.
Better source footage
Improve the chance of a useful guide at recording time
The model has a better chance of following the hitting arm when the player occupies a useful portion of the frame, the hand is not cropped, and the camera does not move. For a forehand, a rear three-quarter or side view often keeps the shoulder-to-wrist chain visible. For a serve, leave generous space above the player so the tossing and hitting arms remain in frame.
Good contrast also matters. A dark shirt against a dark fence, severe backlight, or a wrist hidden behind the torso can make side assignment and joint visibility harder. Record several repetitions: nearby clear frames can support a correction even when the contact frame itself is blurred.
Confirm the hitting hand
Use the manual hand control if automatic evidence is uncertain or incorrect.
Pause on the issue
Select a reported issue to seek to its evidence time and inspect the guide without motion.
Use it on court
Translate the shape into a simple movement cue
Trying to copy a frozen joint angle exactly can make a stroke rigid. Instead, convert the image into one task that preserves athletic movement: create more space before contact, let the elbow travel with the torso, reach upward before pronation, or finish balanced enough to recover.
Test the cue at reduced speed, then progress to a fed ball and finally a rally. Record again only after enough repetitions for the new task to feel familiar. The new clip is evidence of adaptation, not a demand that every frame match the same drawing.
Questions, answered
Frequently asked questions
Why does the correction appear only near one part of the video?
Each visual target belongs to a reported issue and evidence timestamp. During playback, ACEAI shows it only within the relevant time window so a preparation correction is not mistakenly displayed during contact or recovery.
Why is only one arm highlighted?
The overlay is designed to explain the accepted issue with minimal clutter. Highlighting the relevant shoulder, elbow, and wrist is usually clearer than drawing a full skeleton over the entire player.
Can the overlay show exact three-dimensional biomechanics?
No. A single consumer camera produces a two-dimensional view with perspective, occlusion, and blur. The overlay is a visual coaching reference, not motion-capture laboratory data or a medical joint-angle measurement.
What should I do if ACEAI chooses the wrong racket hand?
Use the hand selector in the analysis controls to confirm left or right. A manual confirmation takes precedence and helps prevent a correction from being drawn on the non-racket arm.
Is a dashed or cautious guide still useful?
It can communicate a broad direction, but it should not be copied as an exact pose. Read the issue text, look at the source frame, and use a simple movement cue when practicing.
Train with evidence
Use visual correction when the evidence deserves it.
Record a clear stroke, inspect the timestamped issue, and use the overlay as one input to deliberate practice.