When an AI video tool adds an object, first confirm that the addition was requested. Then check whether it fits the scene, preserves the source image, and remains visually consistent from frame to frame.
First, determine whether the object belongs in the video
Start by comparing the output with the instruction and the source image. Classify the result before judging its polish: Is the object requested, unwanted, or missing even though the prompt asked for it? Object-insertion research identifies failure to add the requested object as one major problem, alongside unsuitable appearance and implausible placement.
This distinction keeps the review focused. An unwanted addition is an instruction-following failure even if it looks convincing. A requested object that never appears is also a failure. If the correct object is present, continue to placement and visual-quality checks rather than treating its mere presence as success.
Check placement, appearance, and preservation of the source scene
Pause on clear frames and inspect the object in context. Ask whether its location plausibly fits what the scene allows. An object should not appear in a position where it seems unsupported, obstructs the scene inexplicably, or otherwise conflicts with the surrounding structure. Next, examine whether its scale, shape, and general appearance suit the scene.
Compare the generated frame with the source image. Look for unintended changes to the original composition, structures, and fine details. Successful insertion requires a balance: preserve the source while allowing changes that the new object logically requires. Shadows and reflections may need to appear, but they should remain coherent with the object and its surroundings. Record each mismatch separately so a later prompt revision can target placement, appearance, preservation, shadow, or reflection problems.
Review identity, lighting, and artifacts across frames
A plausible still frame does not guarantee a consistent video. Scrub through the clip slowly and compare the added object at its first appearance, during motion, and near the end. Check whether its identity, outline, proportions, and surface details remain recognizable. Watch for parts that merge, stretch, disappear, or transform unexpectedly.
Also inspect lighting over time. A supplied overview of Veo 3.1 reports that generated objects can exhibit morphing artifacts and lighting shifts, with results varying across workflows. Its reference-image workflow accepts up to three images intended to help maintain the identity of characters, objects, or scenes across shots, but that intended function does not remove the need for review.
Use the still-image insertion categories as a practical inspection framework, not as proof of how every video system performs. The object-insertion paper evaluates still images, while the reported temporal issues come from a separate third-party product overview.
Conclusion
Use the same sequence for every clip: confirm that the object was requested, judge whether its placement and appearance make sense, compare the source composition and details, and then inspect the full timeline for coherent shadows, reflections, lighting, shape, and identity.
Review the footage frame by frame and record every placement, appearance, lighting, reflection, shadow, morphing, or identity problem. Revise the prompt or regenerate the clip before using or publishing the video.
Disclosures and limitations
- This article was prepared with AI assistance using only the supplied research package and its identified sources.
- The Veo 3.1 evidence comes from a third-party overview and was not independently corroborated; the Add-it research concerns still-image insertion, so it does not by itself establish video performance.
Sources
- Google Veo 3 vs Veo 3.1: What's New and Should You Upgrade? — MindStudio
- Add-it: Training-Free Object Insertion in Images With Pretrained Diffusion Models — arxiv.org
- OracleParameterCollection Class — docs.oracle.com
- Nano Banana + Dreamina Guide: Meet the AI Combo You've Never Seen — Dreamina
Improve this guide
Report a problem or suggest the next question
Submissions enter a private editorial queue. They are reviewed and deduplicated before any public update or new page is created.