HappyHorse 1.1 API

About HappyHorse 1.1

HappyHorse 1.1 is a video family from Alibaba with three endpoints: text-to-video, image-to-video and reference-to-video taking up to nine reference images. Clips run 3 to 15 whole seconds at 720p or 1080p, across nine aspect ratios including 4:5, 5:4, 21:9 and 9:21.

Call it with the model name alibaba/happyhorse-1.1/text-to-video on POST /jobs/createTask, from 105 credits for a 5-second clip ($1.05). New accounts get 30 free credits to try it in the Playground first.

Introduction

HappyHorse 1.1 Text to video is the prompt-only endpoint of Alibaba's HappyHorse 1.1 family: a prompt of up to 2,500 characters returns a clip of 3 to 15 whole seconds at 720p or 1080p, with a generated soundtrack. Nine aspect ratios are available, from 21:9 to 9:21, including the 4:5 and 5:4 feed and print crops.

Choose a HappyHorse 1.1 mode by starting material

Key features

Nine aspect ratios in one field

aspect_ratio accepts 16:9 (the default), 9:16, 1:1, 4:3, 3:4, 4:5, 5:4, 9:21 and 21:9. A set of deliverables in several shapes becomes a loop over one parameter rather than a round of re-framing in post. The rain-hood-convenience example was written for 9:16 at 1080p, the vertical end of that list, and spends its words on one continuous action away from camera.

A soundtrack with no switch

Every clip comes back with generated audio, and there is no field to turn it off. Describe the sound you want: the desert-tailgate brief asks for cicadas and a distant highway, and in rain-hood-convenience the rain hammering the awning arrives in the same pass as the picture. When the clip goes under your own mix, mute or replace the track in the edit.

Draft at 720p, deliver at 1080p

Duration runs from 3 to 15 whole seconds with 5 as the default, and resolution defaults to 720p. Draft at 720p, then re-run the take you want at 1080p; each pass draws its own take, so keep the wording fixed rather than expecting the same frames back at a higher resolution.

Request parameters

Pricing

Prices are in credits, the same credits you use on the website (1 credit = $0.01). The hold is taken when the task is accepted and settled to the actual charge when it finishes; failed tasks are refunded.

For an exact number before you run, send the same body to POST /jobs/quote.

Use cases

Vertical clips with a phone-camera look

The karaoke-room example asks for a device look by name, with rolling shutter, phone-camera noise, slight shake and mixed neon light, in 9:16 at 720p. Two people share one vertical frame, trade a chorus on a single microphone and collapse into each other laughing, and the room sound comes back with the picture.

Mood pieces carried by light

Moving light can hold a whole clip together. In motel-blinds-boots, amber street light through Venetian blinds crawls over the subject while she works off two boots and falls back across a quilt, a chain of actions held inside the default five seconds at 720p. Nothing lights the room except what the prompt describes.

Settle framing and pacing before building frames

When a shot needs an exact subject, or the brief goes past what this endpoint accepts, the path runs through an opening frame on image-to-video or a reference set on reference-to-video. Text-to-video is where framing, light and pacing can be settled in a few quick drafts before those inputs are prepared.

Prompt guide & pro tips

Write it as a shot

Give the subject, action, camera, light and pacing in the order the viewer sees them. The desert-tailgate prompt does this in one paragraph: who is on the tailgate and what she wears, what she does (boots swinging, tipping a bottle, squinting into the low sun), then "warm orange backlight, lens flare, handheld 35mm", then the sound.

Keep the brief within what this endpoint accepts

The prompt is screened before generation, and a description past its content line comes back as a rejection, not as a milder clip. The published examples work through wardrobe, light and gesture rather than spelling everything out. For work beyond that line, start from an image on image-to-video or reference-to-video. With a 2,500-character limit, cut adjectives before you cut actions.

Set the frame before comparing takes

The defaults are 16:9 and five seconds. If the deliverable is 4:5 or 9:21, set it before the first draft, because a composition written for one frame does not translate to another. Keep the move resolvable within the duration you choose, and remember that a written shot leaves wardrobe, body and framing to the model, so re-runs drift.

API quick start

Call the HappyHorse 1.1 API in three steps

1. Create an API key. Sign in to PopNow and create a key in the API console. Keys start with sk-popnow- and use the same credits as the website.
2. Send the request. POST /jobs/createTask with model alibaba/happyhorse-1.1/text-to-video and an input object that follows the parameter table. The response returns a task ID straight away.
3. Get the result. Poll GET /jobs/recordInfo with the task ID, or pass a callBackUrl and we post the result to it. Download the output links when the task succeeds.

# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(uuidgen)"
curl -X POST https://api.popnow.ai/api/v1/jobs/createTask \
  -H "Authorization: Bearer $POPNOW_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $IDEMPOTENCY_KEY" \
  -d '{
  "model": "alibaba/happyhorse-1.1/text-to-video",
  "input": {
    "prompt": "A slow aerial shot drifting over a misty pine forest at sunrise",
    "aspect_ratio": "16:9",
    "resolution": "720p",
    "duration_seconds": 5
  }
}'

# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
  -H "Authorization: Bearer $POPNOW_API_KEY"

Replace the prompt and any links with your own. The API tab has the response, polling and callback reference.

HappyHorse 1.1 API questions

Other video APIs

• MiniMax H3 APIExpressive clips with audio, up to 2KFrom 28 credits for a 5-second clip
• Wan 3.0 APIUp to 30-second clips with synced audioFrom 34 credits for a 5-second clip
• Wan 3.0 Prime APIQuicker Wan 3.0 renders, up to 30 seconds with audioFrom 46 credits for a 5-second clip
• Seedance 2.5 APIByteDance's newest: 30-second clips with native audioFrom 56 credits for a 5-second clip
• Kling 3.0 API4K clips, multi-shot cuts and motion controlFrom 51 credits for a 5-second clip
• Vidu Q4 Preview APIUp to 4K clips with sound and spoken dialogueFrom 34 credits for a 5-second clip

More about HappyHorse 1.1

Try it

HappyHorse 1.1 AI Video Generator onlineCreate videos with HappyHorse 1.1 in PopNow

Docs

HappyHorse 1.1 model ID and input schema in the API docsPopNow API quickstart: your first request in five minutesImage to video guide for the PopNow APIWebhooks: get HappyHorse 1.1 results without polling