ASR API Documentation

Interface Information

POST /openapi/autosubrt/v1/asr

This is the speech recognition service

The base URL of this interface is https://autosubrt.jcaigc.cn, which is a different service (and a different path prefix) from CapCut Mate (https://capcut-mate.jcaigc.cn).

Full URL = https://autosubrt.jcaigc.cn + /openapi/autosubrt/v1/asr

Function Description

Speech recognition: transcribe audio into punctuated full text, split it into sentences by sentence-ending punctuation, and return a timeline for every character of each sentence. Use it when you have audio and want copy or subtitles directly.

For plain text only use ASR Text; for an SRT subtitle file use ASR SRT; to align your own text against the audio use Align Text To Audio.

Punctuation is restored by a dedicated punctuation model (Whisper is unreliable on Chinese punctuation), so text always carries punctuation — the split sentences do too.

Request Parameters

json

{
  "audio_url": "https://example.com/audio.mp3",
  "apiKey": "123e4567-e89b-12d3-a456-426614174000"
}

Parameter Description

Parameter	Type	Required	Default	Description
audio_url	string	✅	-	Audio file URL, must be downloadable by the server
apiKey	string	Required when billing is on	-	A valid UUID; get one at https://jcaigc.cn

Parameter Details

audio_url

Type: string
Description: The server downloads this URL before transcribing, so it must be a direct, publicly reachable link (not a page that requires login)
Format: Any common audio or video file: wav, mp3, m4a, aac, flac, ogg; video files such as mp4 and mov also work (the audio track is extracted server-side)
Limit: 100MB per file (server-side FILE_SIZE_LIMIT, 104857600 bytes by default)

apiKey

Type: string
Description: Must be a valid UUID; required while billing is enabled (it is by default), and the account balance must be greater than 1

Response Format

Success Response (200)

json

{
  "code": 0,
  "message": "Success",
  "data": {
    "text": "多谢，请入席吧。",
    "utterances": [
      {
        "text": "多谢，请入席吧。",
        "words": [
          { "text": "多", "start_time": 2810, "end_time": 3070 },
          { "text": "谢", "start_time": 3070, "end_time": 3330 },
          { "text": "请", "start_time": 4889, "end_time": 5320 },
          { "text": "入", "start_time": 5320, "end_time": 5620 },
          { "text": "席", "start_time": 5620, "end_time": 5860 },
          { "text": "吧", "start_time": 5860, "end_time": 6009 }
        ]
      }
    ]
  }
}

Response Field Description

Field	Type	Description
code	int	0 means success; see the error codes below otherwise
message	string	Human-readable message, Chinese by default, English when `Accept-Language: en` is sent
data.text	string	Full copy, always punctuated
data.utterances	array	Sentence-split result, each item ends with sentence-ending punctuation
data.utterances[].text	string	Text of one sentence, punctuation included
data.utterances[].words	array	Per-character timeline of that sentence, punctuation excluded
data.utterances[].words[].text	string	A single character (Latin text is split into letters)
data.utterances[].words[].start_time	int	Start time (milliseconds)
data.utterances[].words[].end_time	int	End time (milliseconds)

Error Response

json

{
  "code": 2003,
  "message": "Download file failed"
}

Error bodies contain no data field; every error is returned with HTTP 200, so check code instead of the status code.

Usage Examples

cURL Examples

bash

curl -X POST https://autosubrt.jcaigc.cn/openapi/autosubrt/v1/asr \
  -H "Content-Type: application/json" \
  -d '{
    "audio_url": "https://example.com/audio.mp3",
    "apiKey": "123e4567-e89b-12d3-a456-426614174000"
  }'

Python Example

python

import requests

resp = requests.post(
    "https://autosubrt.jcaigc.cn/openapi/autosubrt/v1/asr",
    json={
        "audio_url": "https://example.com/audio.mp3",
        "apiKey": "123e4567-e89b-12d3-a456-426614174000",
    },
    timeout=600,
)

result = resp.json()
if result["code"] != 0:
    raise RuntimeError(result["message"])

for sentence in result["data"]["utterances"]:
    print(sentence["text"])
    for word in sentence["words"]:
        print(word["text"], word["start_time"], word["end_time"])  # milliseconds

Billing

This interface is charged by audio duration and shares the same points system as CapCut Mate.

Item	Description
Price	0.00022 points / second
Basis	Actual audio duration in seconds, as reported by the recognition engine
When charged	Only after a successful recognition; failures are not charged
Balance gate	The account must hold more than 1 point before the call, otherwise it is rejected (2035)

Audio duration	Cost (points)
10 seconds	0.002200
60 seconds	0.013200
1 hour	0.792000

apiKey must be a valid UUID and can be obtained at https://jcaigc.cn.

Error Code Description

Error Code	Error Message	Description	Solution
1001	Parameter validation failed	audio_url missing, or apiKey is not a valid UUID	Check the request parameters
2001	Failed to recognize audio	Audio could not be decoded, model not loaded, or audio_url returned 401/403/404	Try a playable file or a reachable direct link
2002	File size exceeds the limit	Audio is larger than 100MB	Compress or trim it and retry
2003	Download file failed	Network or server error during download, still failing after retries	Make sure it is a public direct download link
2005	Download file timeout	Overall download timed out	Use a faster source or a smaller file
2035	Insufficient account balance	The account needs more than 1 point to keep using the service	Recharge and retry
2036	Invalid apiKey	apiKey missing while billing is enabled	Get an apiKey at https://jcaigc.cn
9997	Server is busy	Concurrency limit reached; the request was not queued	Retry later
9998	Internal server error	Unexpected internal error	Contact technical support
9999	Unknown error	Points service unavailable, etc.	Retry later

Notes

Time unit is milliseconds (1 second = 1000). Note that Align Text To Audio returns microseconds instead.
Sentences are split by sentence-ending punctuation only: a sentence ends on 。！？.!?; commas, enumeration commas and colons stay inside the sentence.
Concatenating all sentences reproduces data.text character by character: "".join(u.text) == data.text.
Punctuation has no timestamp: words only contains real characters; punctuation appears in text only.
When no speech is recognized, data.text is an empty string and data.utterances is an empty array — the call still succeeds.
Repeated calls are charged repeatedly; do not blindly retry after a timeout.

Workflow

Validate apiKey and account balance (while billing is enabled)
Download the audio/video behind audio_url into a server-side temp directory
Run speech recognition to obtain per-character timelines
Restore punctuation with the punctuation model to get the punctuated full text
Split by sentence-ending punctuation; punctuation stays with its sentence
Charge by audio duration after a successful recognition
Return the copy and sentence timelines, then delete the temp file

📚 Project Resources
GitHub: https://github.com/Hommy-master/autosubrt

ASR API Documentation ​

🌐 Language Switch ​

Interface Information ​

Function Description ​

Request Parameters ​

Parameter Description ​

Parameter Details ​

audio_url ​

apiKey ​

Response Format ​

Success Response (200) ​

Response Field Description ​

Error Response ​

Usage Examples ​

cURL Examples ​

Python Example ​

Billing ​

Error Code Description ​

Notes ​

Workflow ​

Related Interfaces ​

ASR API Documentation

🌐 Language Switch

Interface Information

Function Description

Request Parameters

Parameter Description

Parameter Details

audio_url

apiKey

Response Format

Success Response (200)

Response Field Description

Error Response

Usage Examples

cURL Examples

Python Example

Billing

Error Code Description

Notes

Workflow

Related Interfaces