Who makes the voice, and why it decides everything
OmniHuman 1.5 is audio-driven. The pipeline generates a voice track from your script first, then hands the model that track plus your avatar image, and the model animates the person delivering it. The output words are the input words. There is no paraphrasing step where they could change.
Happy Horse 1.1 is prompt-driven with joint audio and video generation. It produces the picture and the soundtrack in one pass, including lip-synced speech across multiple languages, from the scene description you give it. Short lines usually land close to what you asked for, but the model is composing the performance rather than reciting a fixed track.
For an offer ad, that difference is the whole ballgame. If your creative says "40% off through Sunday, code SPRING40", a model that improvises is a liability. If your creative is a lifestyle moment where someone says something warm and vague about the product, improvisation costs you nothing and saves you a scripting pass.
What OmniHuman 1.5 gives you: exact words, longer takes, no scene
OmniHuman 1.5 is ByteDance's avatar animation model. Its inputs are an image and an audio track, and that is genuinely all it takes: there is no duration slider and no resolution slider, because the length of the video is the length of the audio and the price is the same at 720p and 1080p.
That last point is worth acting on. A 15-second OmniHuman render is 490 credits whether you ask for 720p or 1080p, so there is no reason to ever pick the lower resolution on this model. Take the 1080p file.
The ceiling is 30 seconds in one continuous take, which is the longest unbroken talking-head render of the two by double. A full direct-response read, hook through to call to action, fits inside a single generation with no cut.
What you give up is the frame. OmniHuman animates the person and leaves the world alone: the background is whatever was in your source photo, there is no camera move, and there is no way to prompt a product into the shot. If you want a specific setting, you build it into the image before you generate.
What Happy Horse 1.1 gives you: a directed scene and nine reference slots
Happy Horse 1.1 is Alibaba's video model, running here as image to video with native joint audio. You describe the shot, it renders 5, 10 or 15 seconds with sound, at your choice of 720p or 1080p, in portrait, landscape or square.
The feature that separates it from most talking-head options is its reference image handling. It accepts up to nine images at once. One image behaves like a first frame to animate. Two or more become references, which is how you keep a specific product, a specific face from several angles, or a specific set consistent across a batch of clips. That is a real workflow advantage when you are shooting a campaign rather than a one-off.
Unlike OmniHuman, resolution here is a genuine cost lever rather than a label. 720p is a cheaper render and it is priced that way: 420 credits for 15 seconds against 550 at 1080p. If the clip is a mid-funnel test that will never be cropped, the cheaper tier is a defensible choice.
The billing models are different, and it changes how you brief
Happy Horse 1.1 is billed in fixed duration tiers. Five, ten or fifteen seconds, each at a set credit price: 140, 280 and 420 at 720p, or 180, 370 and 550 at 1080p. You know the cost before you write a word, and a longer script inside the same tier costs nothing extra.
OmniHuman 1.5 is billed by how long your script takes to say. The estimate runs at roughly 2.3 spoken words per second, at about 33 credits per spoken second, and the price you see on the generate button is the price you are charged. A 35-word hook is around 16 seconds and roughly 520 credits. A 60-word read is around 27 seconds and roughly 880 credits, about $8.64 on Starter.
The practical consequence: on OmniHuman, cutting your script is cutting your bill. Tightening a 60-word read to 40 words is not just better ad copy, it is around 300 credits back. On Happy Horse, script length only matters when it pushes you into the next duration tier.
It also changes how you brief. An OmniHuman brief is a script. A Happy Horse brief is a scene description with a line of dialogue in it. Writing one as if it were the other is the most common way to get a disappointing render from either model.
The real cost math side by side
Here are the live prices on UGC Vids AI. OmniHuman 1.5: 490 credits for 15 seconds, 980 for 30 seconds, identical at 720p and 1080p. Happy Horse 1.1 at 720p: 140 for 5 seconds, 280 for 10, 420 for 15. At 1080p: 180 for 5 seconds, 370 for 10, 550 for 15.
On the $49 Starter plan (5,000 credits, just under a cent each) that is about $4.80 for a 15-second OmniHuman take, $9.60 for a 30-second one, $4.12 for a 15-second Happy Horse render at 720p and $5.39 at 1080p.
Per second of finished video the two are within a few credits of each other at the 15-second mark: about 33 credits per second on OmniHuman, 28 on Happy Horse at 720p, 37 at 1080p. Where they separate is at short lengths. Happy Horse will give you a 5-second clip for 180 credits at 1080p; OmniHuman's floor is the length of your script, and short scripts still carry the per-second rate, so it is not the model to reach for when you want a three-second beat.
Volume on one Starter month: about 10 fifteen-second OmniHuman takes, or 9 fifteen-second Happy Horse renders at 1080p, or 27 five-second Happy Horse clips at 1080p. On the $99 Growth plan at 12,000 credits, roughly 24 OmniHuman takes.
Briefs that decide themselves
Testimonials and founder reads: OmniHuman 1.5. The words are the asset, the take needs to run 15 to 30 seconds without a cut, and the face stays locked to the photo you chose.
Offer and compliance-sensitive ads: OmniHuman 1.5, without much debate. Prices, guarantees, dosage claims, and anything a reviewer signed off on need a model that recites rather than composes.
Product-in-hand and lifestyle clips: Happy Horse 1.1. You want the scene, the motion and the product to be right, and the multi-reference input is built for exactly that.
Campaigns that need one consistent character across many shots: Happy Horse 1.1, using several angles of the same face as reference images.
Anything under 10 seconds: Happy Horse 1.1, because it has real short-form tiers and OmniHuman's price follows the script rather than a duration you choose.
A common pairing is to build the ad's opening on Happy Horse, where the product and setting need to be right, then carry the offer and call to action on an OmniHuman take where the wording is fixed. Both models draw on the same credit balance, so that is two generations on one plan.
Verdict: pick by who controls the words
Because the prices land so close together at 15 seconds, budget will not make this decision for you. Control will. OmniHuman 1.5 gives you the script and takes the scene away. Happy Horse 1.1 gives you the scene and takes some of the script away.
If you sell something where the claim is specific, default to OmniHuman and treat Happy Horse as your b-roll and product-shot engine. If you sell something visual where the copy lives in the caption and the on-screen text, default to Happy Horse and keep OmniHuman for the occasional talking-head test.
Both models are in the same picker on UGC Vids AI, on one credit balance and with no per-video limit, so the honest way to settle it is to run the same offer through each on a plan and let your ad account decide. The trial is $1 for 7 days. Cancel anytime.