Kling Video V3

The three models share PopGo's video task API, but differ in image count, frame semantics and output formats. Reference video and reference audio are not exposed by this integration. The service documentation's “audio” column does not declare an audio-reference input.

Model differences

Model	Images	Output audio (service documentation)	Resolution
kling-video-v3	Up to 2; first image = first frame, second = last frame	Supported	720p / 1080p / 4K
kling-video-v3-omni	Up to 7 reference images	Supported	720p / 1080p / 4K
kling-video-v3-turbo	One first frame only	Audio unsupported	720p / 1080p

Fields and defaults

Field	Type	Rule
model	string	Required; use a public model ID above
prompt	string	Required; describe subjects, movement and camera
seconds / duration	integer	Integer 3–15 seconds; set explicitly, UI default 5 seconds
resolution	string	Select 720p / 1080p / 4K per model; UI default 720p, service default 4K; Turbo excludes 4K
aspect_ratio	string	16:9 / 9:16 / 1:1; default 16:9; see image guidance below
reference_images	object[]	Object array; each item uses url or image_url with a public HTTP(S) URL or complete image Data URL

Use reference_images

Use the object array below for direct API calls. PopGo also normalizes Canvas file uploads and frame fields, but clients should not send multiple aliases together. Public URLs are optional; local images may be encoded as complete Data URLs. Sharing pages, login URLs and filesystem paths are not image URLs.

curl -X POST https://api.popgo.site/v1/videos \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "YOUR_MODEL",
    "prompt": "A person turns toward the camera",
    "seconds": 5,
    "resolution": "720p",
    "reference_images": [
      {"url": "YOUR_IMAGE_URL"}
    ]
  }'

Text-to-video: omit reference_images. Otherwise preserve array order. For the standard model, two images are the first and last frames, not two ordinary style references. Omni uses multiple images for subject/style references; Turbo rejects more than one image.

Aspect ratio and output

The service documentation records a 1024×1536 first frame producing 2352×3524 output on the standard model: the aspect ratio follows the first image. Crop the input first when you need a specific frame. Do not assume aspect_ratio overrides every image workflow. Canvas currently hides aspect ratio for first-frame mode.

A documented Omni 5-second 4K sample was 3840×2160, 24 fps, about 5.042 seconds, 8.9 Mbps and 5.6 MB. This is one observed output, not a fixed bitrate or file-size guarantee.

Unsupported and unconfirmed fields

None of these three models currently exposes reference_video, video_reference, reference_audio or a motion-control reference workflow. generate_audio controls the output track; it is not reference media. The current Canvas preset does not expose that output toggle. The name Omni does not imply motion-control support.

Unlisted fields such as quality may be silently ignored. HTTP 200 does not prove a field was used; do not infer seed or watermark support from generic video conventions. Confirm the current interface specification and inspect results before enabling new fields.

Four polling caveats

1. The service documentation records progress remaining at 0 until completed / 100. This alone does not mean the job is stuck; do not invent intermediate percentages.
2. The polling model field may be empty; retain the submitted model ID.
3. usage may be absent; use PopGo usage and billing records rather than assuming the task was free.
4. Resolution, duration and frame rate may be absent; probe the downloaded media. Response timestamps are not a reliable elapsed-time measurement.

Three documented runs took about 140, 200 and 420 seconds. Poll every 10 seconds and allow at least 15 minutes; this is not a latency guarantee. After a local timeout, query the original task instead of submitting another one.

Errors and corrections

Symptom	Action
400 invalid parameters	Check duration, ratio, resolution and image-count allowlists; do not repeat unchanged
404 model or task missing	Check public model ID, token permissions and the task ID returned by PopGo
503 no available account / 502 temporary service failure	Use bounded backoff; after a create timeout, check whether a task already exists
Successful video ignores the image	Check the actual reference_images payload and media access, then compare the frame/subject; a task ID alone proves nothing about reference use
Turbo with 4K or audio parameters	Remove unsupported parameters; use 720p / 1080p

Download through PopGo's /content proxy or a usable result URL from the response. Allow sufficient time for large files and never send the PopGo API Key to a third-party media host. See Video task workflow for complete polling, download and retry examples. Pricing follows Models and pricing.