Video Transition API - Join Clips With Fades, Wipes and Slides: Pricing, Documentation
by Pixazo
Join clips with a real transition rather than a hard cut. Pick a family - fades, wipes, slides, smooth, geometric, diagonals, slices, wind, cover-reveal or texture - then name the exact effect in transition, giving you all 58 of ffmpeg's transitions rather than a handful. Set the length with crossfade_seconds, from 0.2 to 3 seconds, and shape the audio blend with audio_curve, including nofade to leave a music bed untouched. Accepts 2 to 4 MP4 or MOV clips totalling up to 60 seconds of source.

Models Version
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Video Transition 1.0 API Documentation
https://gateway.pixazo.ai/media-tools/v1/video-transition
Authentication
All requests require an API key passed via header.
Pricing: Billed at $0.004 per second of the produced video — the total length of the clips you join. Joining three 30-second clips costs $0.18. Combined source is capped at 60 seconds.
Rounding: billing is per second but always rounds up to a whole second — a 5.06-second source bills as 6 seconds. The shortest billable job is 1 second.
Retries: this is an asynchronous job on shared encoding capacity, so a request can occasionally come back processing_failed or take much longer than usual. These are transient and succeed on a retry, and a failed job is never charged — the wallet hold is released. If you chain these tools, retry a failed step rather than failing the whole pipeline.
Inputs must be MP4 or MOV. Anything else — WebM, MKV, AVI — is rejected up front with every video_urls entry must be a readable MP4/MOV. The reason is billing, not capability: a merge is priced on the SUM of its clips, so every clip’s duration has to be measured before the job is accepted, and that measurement reads the MP4/MOV container only. Rejecting is deliberate — guessing a duration would mis-charge you. Convert other formats with the Video Converter API first, then merge.
| Header | Type | Required | Description |
|---|---|---|---|
| Ocp-Apim-Subscription-Key | string | Yes | Your API subscription key |
Video Transition generate request
Request Code
POST https://gateway.pixazo.ai/media-tools/v1/video-transition
Content-Type: application/json
Cache-Control: no-cache
Ocp-Apim-Subscription-Key: YOUR_API_KEY
{
"video_urls": [
"https://api-assets.pixazo.ai/media-api-test/t.mov",
"https://api-assets.pixazo.ai/media-api-test/t.mov"
],
"family": "fades",
"transition": "dissolve",
"crossfade_seconds": 1.0
}
import requests
url = "https://gateway.pixazo.ai/media-tools/v1/video-transition"
headers = {
"Content-Type": "application/json",
"Cache-Control": "no-cache",
"Ocp-Apim-Subscription-Key": "YOUR_API_KEY"
}
data = {
"video_urls": [
"https://api-assets.pixazo.ai/media-api-test/t.mov",
"https://api-assets.pixazo.ai/media-api-test/t.mov"
],
"family": "fades",
"transition": "dissolve",
"crossfade_seconds": 1.0
}
response = requests.post(url, json=data, headers=headers)
print(response.json())
const url = "https://gateway.pixazo.ai/media-tools/v1/video-transition";
const headers = {
"Content-Type": "application/json",
"Cache-Control": "no-cache",
"Ocp-Apim-Subscription-Key": "YOUR_API_KEY"
};
const data = {
"video_urls": [
"https://api-assets.pixazo.ai/media-api-test/t.mov",
"https://api-assets.pixazo.ai/media-api-test/t.mov"
],
"family": "fades",
"transition": "dissolve",
"crossfade_seconds": 1.0
};
fetch(url, {
method: "POST",
headers: headers,
body: JSON.stringify(data)
})
.then(response => response.json())
.then(data => console.log(data));
curl -X POST "https://gateway.pixazo.ai/media-tools/v1/video-transition" \
-H "Content-Type: application/json" \
-H "Cache-Control: no-cache" \
-H "Ocp-Apim-Subscription-Key: YOUR_API_KEY" \
--data-raw '{
"video_urls": [
"https://api-assets.pixazo.ai/media-api-test/t.mov",
"https://api-assets.pixazo.ai/media-api-test/t.mov"
],
"family": "fades",
"transition": "dissolve",
"crossfade_seconds": 1.0
}'
Output
{
"request_id": "media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
"status": "QUEUED",
"polling_url": "https://gateway.pixazo.ai/v2/requests/status/media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
}
Webhook (Optional)
Add the X-Webhook-URL header to your generate request to receive a POST callback instead of polling.
X-Webhook-URL: https://your-server.com/webhook/callback
Request Parameters - Video Transition generate request
| Parameter | Required | Type | Default | Allowed values / range | Description |
|---|---|---|---|---|---|
| video_urls | Yes | array of strings | — | 2 – 4 items; each an HTTP(S) URL to an MP4 or MOV; combined length ≤ 60 s | The clips to join, in the order given, with a transition between each pair. Every entry must be readable — if any one cannot be measured the request is rejected before you are charged. |
| family | Yes | enum | — | fades, wipes, slides, smooth, geometric, diagonals, slices, wind, cover-reveal, texture | Which group of transitions to use. Pick the family for the effect you want — a dip or blend (fades), a travelling edge (wipes, smooth, diagonals), a moving clip (slides, cover-reveal), a shape opening or closing (geometric), banded or streaky dissolves (slices, wind), or an optical effect (texture). Then name the exact one in transition. |
| transition | Yes | enum | — | Depends on family — see Transitions by family below | The specific transition, which must belong to the family you named. A valid transition from the wrong family is rejected with a 400 listing that family's values, so the two fields can never disagree silently. |
| audio_curve | No | enum | tri | nofade, tri, qsin, esin, hsin, log, ipar, qua, cub, squ, cbr, par, exp, iqsin, ihsin, dese, desi, losi, sinc, isinc, quat, quatr, qsin2, hsin2 | The fade shape applied to the audio at each join. tri (the default) is a straight linear crossfade. nofade leaves the audio untouched through the join — useful when a continuous music bed should not dip. The rest are easing curves: qsin, hsin and esin are sine-based and sound gentler than linear; log, exp and par weight the fade toward one side. |
| crossfade_seconds | No | number | 1.0 | 0.2 – 3 | How long each transition lasts. It must be shorter than the first and last clips, and at most half of any clip between them — otherwise the request is rejected with a message naming the clip. That rule is deliberate: a longer fade would consume a clip entirely and silently drop it from the output. |
| target_resolution | No | enum | — (matches the first clip) | 480p, 720p, 1080p | Normalise every clip to this size before joining. Omit it and the first clip's dimensions are used. |
Transitions by family. Both family and transition are required, and the transition must be one of the values listed for the family you chose. The bold value in each row is a good default if you have no preference. All 58 are available.
| family | Valid transition values | What it looks like |
|---|---|---|
fades | fade, fadeblack, fadewhite, fadegrays, fadefast, fadeslow, dissolve | Blends and dips. Straight cross-dissolves, dips through black/white/grey, and a grainy per-pixel dissolve. |
wipes | wipeleft, wiperight, wipeup, wipedown, wipetl, wipetr, wipebl, wipebr | A hard edge travels across the frame, revealing the next clip. Four sides plus four corners. |
slides | slideleft, slideright, slideup, slidedown | Both clips move together — the outgoing one is pushed off frame. |
smooth | smoothleft, smoothright, smoothup, smoothdown | The same directions as a wipe, but with a soft, ramped edge instead of a hard line. |
geometric | circleopen, circleclose, circlecrop, rectcrop, vertopen, vertclose, horzopen, horzclose, radial | A shape opens or closes over the frame. radial sweeps around the centre like a clock hand. |
diagonals | diagtl, diagtr, diagbl, diagbr | The boundary runs corner to corner. |
slices | hlslice, hrslice, vuslice, vdslice | The frame is cut into bands that swap one after another. |
wind | hlwind, hrwind, vuwind, vdwind | A streaky, directional dissolve, as if blown across the frame. |
cover-reveal | coverleft, coverright, coverup, coverdown, revealleft, revealright, revealup, revealdown | One clip moves over or off a stationary one. cover* slides the incoming clip on top; reveal* slides the outgoing clip away to expose it. |
texture | zoomin, pixelize, hblur, distance, squeezeh, squeezev | Optical and sampling effects rather than a moving boundary — zoom, blur, pixelate, squeeze. |
Example Request
{
"video_urls": [
"https://api-assets.pixazo.ai/media-api-test/t.mov",
"https://api-assets.pixazo.ai/media-api-test/t.mov"
],
"family": "fades",
"transition": "dissolve",
"crossfade_seconds": 1.0
}
Response
{
"request_id": "media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
"status": "QUEUED",
"polling_url": "https://gateway.pixazo.ai/v2/requests/status/media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
}
Request Headers
| Header | Value |
|---|---|
| Content-Type | application/json |
| Cache-Control | no-cache |
| Ocp-Apim-Subscription-Key | YOUR_API_KEY |
Response Handling
Common status codes.
| Code | Meaning |
|---|---|
| 202 | Accepted — Request queued |
| 400 | Bad Request |
| 401 | Unauthorized |
| 402 | Insufficient Balance |
| 403 | Forbidden |
| 429 | Too Many Requests |
| 500 | Internal Server Error |
Error Responses
Queue system errors and model validation errors.
Queue System Errors
// 402 — Insufficient balance
{
"error": "Insufficient Balance",
"message": "Your wallet does not have enough balance."
}
// 400 — Model not found
{
"error": "Model not found",
"message": "Model 'media-transition' not found or is disabled"
}
Error via Status/Webhook
{
"request_id": "media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
"status": "ERROR",
"model_id": "media-transition",
"error": "Description of the error",
"output": null
}
Retrieving Results
Poll the universal status endpoint to check progress and retrieve results.
Endpoint
GET https://gateway.pixazo.ai/v2/requests/status/{request_id}
Ocp-Apim-Subscription-Key: YOUR_API_KEY
cURL Example
curl -H "Ocp-Apim-Subscription-Key: YOUR_API_KEY" \
"https://gateway.pixazo.ai/v2/requests/status/media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
Response (Completed)
{
"request_id": "media-transition_019dxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
"status": "COMPLETED",
"model_id": "media-transition",
"error": null,
"output": {
"media_url": [
"https://pub-582b7213209642b9b995c96c95a30381.r2.dev/v1/media-transition_019dxxxx/output.mp4"
],
"media_type": "video/mp4"
},
"created_at": "2026-03-31T10:00:00.000Z",
"updated_at": "2026-03-31T10:00:15.000Z",
"completed_at": "2026-03-31T10:00:15.000Z"
}
Response Fields
| Field | Type | Description |
|---|---|---|
| request_id | string | Unique request identifier |
| status | string | QUEUED, PROCESSING, COMPLETED, FAILED, or ERROR |
| model_id | string | Model that processed the request |
| error | string|null | Error message if failed |
| output.media_url | array | URLs to generated media (R2 CDN) |
| output.media_type | string | MIME type of the output |
| created_at | string | When request was created |
| completed_at | string | When request completed |
| polling_url | string | Status URL (initial response only) |
Status Values
| Status | Description |
|---|---|
| QUEUED | Request accepted, waiting to be processed |
| PROCESSING | Being processed by the model |
| COMPLETED | Done — output contains the result |
| FAILED | Failed — check error field |
| ERROR | System error — not charged |
Status Flow
QUEUED → PROCESSING → COMPLETED
→ FAILED
→ ERROR
Typical Workflow
- Send a generate request to the API endpoint
- Save the
request_idfrom the response - Poll every 5-10 seconds:
GET /v2/requests/status/{request_id} - When
statusis"COMPLETED", download fromoutput.media_url
Tip: Use X-Webhook-URL header to get a callback instead of polling.
Video Transition 1.0 API Pricing
⚡ Performance
Live usage measured on Pixazo's gateway, split by model version. Generation time is how long a generation takes end-to-end (lower is better). Success rate is the percent of generations that complete (higher is better).
〰 Uptime
Percent of generations that succeeded over the selected period, per model version.