> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apiyi.com/llms.txt
> Use this file to discover all available pages before exploring further.
# VEO 3.1 Official vs Reverse Channel Comparison
> Full-dimension comparison of VEO 3.1 Official (this series) vs existing VEO 3.1 (Reverse Channel) — pricing, capabilities, decision tree, and scenario-by-scenario recommendations.
APIYI provides two Veo 3.1 channels simultaneously. This page helps you **pick by scenario**: official quality + can accept async polling → **Official** (this series); cost-sensitive + need streaming sync or frame-to-video → **Reverse** ([VEO 3.1](/en/api-capabilities/veo/overview)). Both channels can be **used in parallel under the same account** without conflict.
## Full Comparison Matrix
| Dimension | **Official** (this series) | **Reverse** ([existing VEO 3.1](/en/api-capabilities/veo/overview)) |
| - | - | - |
| **Channel type** | Transparent passthrough to Google AI Studio | Reverse-engineered access to Google Flow |
| **Model IDs** | `veo-3.1-generate-preview` / `veo-3.1-fast-generate-preview` | `veo-3.1` / `veo-3.1-fast` / `-landscape` / `-fl` series (8 variants) |
| **Billing mode** | Pay-per-request (independent of duration / resolution) | Pay-per-request (independent of duration / resolution) |
| **Price** | \$0.3 (fast) / \$1.2 (standard) | \$0.15 (fast) / \$0.25 (standard) — **50–75% cheaper** |
| **Endpoint paths** | `POST /v1/videos` only (async) | `POST /v1/chat/completions` (streaming sync) + `POST /v1/videos` (async) |
| **Streaming sync** | ❌ Async polling only | ✅ Supports `stream: true` for live progress |
| **Duration** | 4 / 6 / 8 seconds (string) | Fixed 8 seconds |
| **Resolution** | 720p / 1080p / 4k (three tiers) | HD landscape (1280×720) / portrait (720×1280) |
| **Reference image** | 1 image via `input_reference` (multipart) | 1–2 images (**supports frame-to-video** with `-fl` series) |
| **Landscape / portrait** | Via `aspectRatio` parameter | Via model ID (`-landscape` series) |
| **Group** | `Default` | `Default` |
| **Billing model** | Pay-per-request ✅ / Pay-as-you-go Priority ✅ (pure Pay-as-you-go ❌) | Pay-per-request ✅ / Pay-as-you-go Priority ✅ |
| **Response fields** | `id` / `task_id` / `status` / `progress` (coarse 0/50/100) | Sync: full chat completion; async: `task_id` / `status` |
| **Failed billing** | ❌ Not billed | ❌ Not billed |
| **Audio** | Native synchronized audio | Native synchronized audio |
| **When to use** | Production needing official quality + can accept async polling | Cost-sensitive, needs sync UI progress, needs frame-to-video |
## Three-Step Decision Tree
* **Yes** → Use **[VEO 3.1 (Reverse)](/en/api-capabilities/veo/overview)** `-fl` series (e.g., `veo-3.1-landscape-fast-fl`); Official **does not yet expose** frame-to-video
* **No** → Go to Q2
* **Yes** (user-facing UI can't go blank) → Use **[VEO 3.1 (Reverse)](/en/api-capabilities/veo/overview)** `/v1/chat/completions` streaming endpoint
* **Backend tasked** (queue consumer, batch production) → Go to Q3
* **Budget first** (\$0.15 vs \$0.3 difference matters) → Use **[VEO 3.1 (Reverse)](/en/api-capabilities/veo/overview)**, 50% lower price
* **Quality / stability first** (final delivery, 4K, strong instruction following) → Use **Official** (this series) with `veo-3.1-generate-preview`
* **Iteration / preview** → Use **Official** `veo-3.1-fast-generate-preview` (\$0.3) or **Reverse** `-fast` (\$0.15)
## Scenario-by-Scenario Recommendations
| Business scenario | Recommended channel | Recommended model | Why |
| - | - | - | - |
| Short-video matrix batch production (100+/day) | **Reverse** | `veo-3.1-landscape-fast` | \$0.15 unit price, controllable batch cost |
| Final client ad delivery | **Official** | `veo-3.1-generate-preview` | Stable official quality + 4K optional |
| Frontend live display (needs loading animation) | **Reverse** | `veo-3.1-landscape-fast` + streaming sync | Visible progress, avoids blank-wait anxiety |
| Static poster + frame-to-video → motion clip | **Reverse** | `veo-3.1-landscape-fast-fl` | Frame-to-video capability |
| 4K cinematic clips (hero asset) | **Official** | `veo-3.1-generate-preview` + `resolution=4k` | Only Official supports 4K |
| Overseas team onboarding (existing Key unchanged) | **Official** | `veo-3.1-fast-generate-preview` | Default group + pay-per-request, zero friction |
| Same-prompt multi-seed style exploration | **Official** | `veo-3.1-fast-generate-preview` | 4–6 sec optional, low iteration cost |
| Iteration + final delivery workflow | Mixed | Reverse fast iterate → Official standard final | Cheap iteration, stable delivery |
## Can I use both channels together?
**Absolutely**. The two channels are independently routed:
* Under the same account, **a single Token** (on the Default group) can call both channels simultaneously; billing is tracked per-call
* Switch the `model` field as needed in your business code:
* To use Official → `veo-3.1-fast-generate-preview` / `veo-3.1-generate-preview`
* To use Reverse → `veo-3.1-fast` / `veo-3.1-landscape` / `veo-3.1-fl` etc.
**Recommended setup**: Route "business-critical delivery" to Official, route "iteration / batch previews / sync UI" to Reverse. Unified account, clean billing, complementary capabilities.
## Related Docs
* [VEO 3.1 Official Overview](/en/api-capabilities/veo-3-1-official/overview) — Official channel complete intro
* [VEO 3.1 (Reverse) Overview](/en/api-capabilities/veo/overview) — Existing Reverse channel complete intro
* [VEO 3.1 Official Text-to-Video Playground](/en/api-capabilities/veo-3-1-official/text-to-video)
* [VEO 3.1 Official Image-to-Video Playground](/en/api-capabilities/veo-3-1-official/image-to-video)
* [VEO 3.1 (Reverse) Quick Start](/en/api-capabilities/veo/quick-start) — Streaming sync usage
* [VEO 3.1 (Reverse) Async API](/en/api-capabilities/veo/async-api) — Includes frame-to-video usage
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