DaVinci Resolve APIAdvancedRender

How to Start One Render Job with the DaVinci Resolve Python API

Use StartRendering with a specific job ID without launching stale tasks in the queue

Start only the Render Job you just created, trying compatible job-ID representations where necessary, instead of triggering every task that may remain in the Render Queue.

API

Resolve Scripting API

Language

Python

Resolve

19–20+

Requires

Running Resolve

Syntax

ok = project.StartRendering([job_id])

Parameters

• The relevant arguments are shown in the complete working example below. Validate paths, object types, and required project state before calling the API method.

Returns

Always validate the returned object, list, identifier, or boolean before continuing to the next automation step.

Complete working Python exampleuse it as a starting point for your own script

import os
import sys
import time
from pathlib import Path


def import_resolve_module():
    try:
        import DaVinciResolveScript as dvr
        return dvr
    except ImportError:
        search_paths = [
            os.environ.get("RESOLVE_SCRIPT_API", ""),
            os.environ.get("RESOLVE_MODULES", ""),
            r"C:\ProgramData\Blackmagic Design\DaVinci Resolve\Support\Developer\Scripting\Modules",
            "/opt/resolve/Developer/Scripting/Modules",
            "/opt/BlackmagicDesign/DaVinciResolve/Developer/Scripting/Modules",
            "/Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules",
            str(Path.home() / "Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules"),
        ]
        for path in search_paths:
            if path and os.path.isdir(path) and path not in sys.path:
                sys.path.append(path)
        import DaVinciResolveScript as dvr
        return dvr


def safe_call(obj, name, *args, **kwargs):
    try:
        fn = getattr(obj, name, None)
        if callable(fn):
            return fn(*args, **kwargs)
    except Exception:
        return None
    return None


def get_project_and_timeline():
    dvr = import_resolve_module()
    resolve = dvr.scriptapp("Resolve")
    if not resolve:
        raise RuntimeError("DaVinci Resolve API is unavailable")

    project_manager = safe_call(resolve, "GetProjectManager")
    project = safe_call(project_manager, "GetCurrentProject") if project_manager else None
    if not project:
        raise RuntimeError("No DaVinci Resolve project is open")

    timeline = safe_call(project, "GetCurrentTimeline")
    if not timeline:
        raise RuntimeError("No active Timeline")

    return resolve, project, timeline



def start_single_render_job(project, job_id):
    variants = [
        [job_id],
        [str(job_id)],
        job_id,
        str(job_id),
    ]
    try:
        variants.insert(2, [int(job_id)])
        variants.append(int(job_id))
    except Exception:
        pass

    for value in variants:
        if safe_call(project, "StartRendering", value):
            return True, f"targeted:{type(value).__name__}"

    return False, "targeted_start_failed"


resolve, project, timeline = get_project_and_timeline()
job_id = safe_call(project, "AddRenderJob")
if not job_id:
    raise RuntimeError("Configure the render and create a Render Job first")

started, mode = start_single_render_job(project, job_id)
print("Started:", started, "mode:", mode, "job_id:", job_id)

Guide

What the example does

Resolve builds can expose job IDs as strings or numbers and may accept a single ID or a list. The helper tries a small set of equivalent representations and reports which form successfully started the intended job.

Why StartRendering() without arguments is avoided

A no-argument call can start the entire queue. When stale jobs are present, that can produce unexpected exports. Targeting the freshly created job ID is the safer automation pattern.

When this approach is especially useful

Targeted execution is valuable in production tools that users can run repeatedly. Even when the queue was not cleaned perfectly, the script still attempts to start only the new task rather than every historical job.

How the example works

Connect to Resolve

Establish a Resolve Scripting API connection and stop early if the application object is unavailable.

Validate the current context

Check the active project, Timeline, Media Pool, source paths, or Render Queue state required by this specific operation.

Run the core API operation

Execute the operation demonstrated in this guide: how to start one render job with the davinci resolve python api.

Validate the result

Check the returned value before the workflow continues. Resolve methods often signal an unavailable object or failed operation with None, False, or an empty result.

Resolve API notes

Create the Render Job with AddRenderJob() before trying to start it.
If every StartRendering form is rejected, verify the Deliver-page configuration and the job ID.
Job-ID types can differ across Resolve scripting versions.
For stricter workflows, clean or inspect the Render Queue before adding the new job.

Common errors

Resolve API is unavailable

Reason: Resolve is closed or Python cannot import/use DaVinciResolveScript.

Fix: Start Resolve and verify the Developer/Scripting/Modules path from the same Python interpreter used by the script.

The method returns None or False

Reason: A required project, Timeline, clip, preset, path, or application state is missing.

Fix: Validate each input and add explicit result checks after important Resolve API calls.

The script only works on one workstation

Reason: Paths or environment assumptions are hard-coded for a single operating system or machine.

Fix: Move paths into configuration and support the required Windows, Linux, and macOS locations explicitly.

Next step

Continue only after the current operation has returned the expected Resolve object or result.

Related API guides

Render