Nodes/KIE.ai Nodes Next/Qwen 2.1 - Text to Image
ComfyUI Node

Qwen 2.1 - Text to Image

Text rendering, transparency, and a seed that works

By felipederosilva·Created 2 months ago·Updated 5 days ago· 3
Qwen 2.1 - Text to Image
    • image
    • url
    • all_urls_json
    • task_id
    • raw_json
    • credits_consumed
    • credits_left
    ◄promptA corgi wearing a yellow rain hat sitting on stone steps after the rain, shallow depth of field►
    ◄aspect_ratio16:9►
    ◄resolution1K►
    ◄backgroundopaque►
    ◄output_formatpng►
    ◄enhance_prompttrue►
    ◄seed20260921►
    ◄nsfw_checkerfalse►
    ◄timeout_seconds1200►
    ◄callback_url►

    Two reasons people reach for a hosted Qwen image model rather than a local checkpoint: it renders text inside images better than most local bases, and it hands back a real alpha channel when you ask for a transparent background. Both are things open local workflows still fiddle with. This node is the text-to-image half of that - prompt in, IMAGE out, no reference required.

    It's also the cheapest sensible way to prototype a composition before you commit to a local render pipeline. Generate the layout, check the framing, then rebuild it locally with the model you actually want to ship.

    What it's doing

    A KIE Market job, model qwen2-1/text-to-image. The node submits your prompt plus the optional fields, polls the task, downloads the result and decodes it into a ComfyUI IMAGE tensor. Nothing local runs. Every execution is a billed call, and the pixels go through KIE's infrastructure - that's the trade for not owning the GPU.

    Worth knowing because it changes how you prompt: enhance_prompt is on by default, so the model rewrites your words into a fuller scene description before generating. Helpful for composition, unhelpful if you're testing a specific phrasing - turn it off when the wording itself is what you're evaluating.

    Inputs

    • prompt - required, up to 5000 characters, any language. Be specific about the text you want rendered (wrap it in quotes in the prompt) and about the composition.
    • aspect_ratio - 16:9 is the node's default even though the API's own default is 1:1; the full list covers 1:1, 4:3, 3:4, 3:2, 2:3, 9:16, 21:9, 9:21. Set it deliberately, because the pixel size is the ratio times the resolution tier.
    • resolution - 1K or 2K. Only those two; 4K is rejected. 2K is four times the pixels and noticeably slower.
    • background - opaque (default) or transparent. Transparent produces a genuine alpha channel in PNG or WebP. The prompt rule that trips people up: when you ask for transparency, describe only the subject. Any mention of a background, a surface or a scene tends to produce an opaque image.
    • output_format - png, webp or jpeg. JPEG has no alpha, so it can't be combined with a transparent background.
    • enhance_prompt - on. The single most consequential boolean here.
    • seed - the reason this node is nicer to iterate on than some hosted competitors: the same seed with the same prompt and parameters reproduces the image within a service version. Lock it once you've found your composition.
    • nsfw_checker - ships false, meaning no additional filtering pass beyond the provider's own.
    • timeout_seconds, callback_url - defaults; leave the callback empty.

    Outputs: image, url, all_urls_json, task_id, raw_json, credits_consumed, credits_left. all_urls_json is worth keeping an eye on: if the provider returns more than one result, you get every URL, not just the one the node decoded.

    Install

    cd ComfyUI/custom_nodes
    git clone https://github.com/felipederosilva/ComfyUI-KIE-Nodes-Next
    cd ComfyUI-KIE-Nodes-Next && pip install -r requirements.txt
    # restart ComfyUI
    

    Or Manager → search "KIE.ai Nodes Next". Dependencies: requests, Pillow, numpy, PyYAML. No model files, no VRAM, so the install is a few seconds. Then one key paste in Settings → KIE.ai Nodes Next → Connection - tested against KIE before it's saved, kept out of workflow JSON, shown only as a masked fingerprint.

    Failure modes and honest advice

    Transparency requests that come back opaque are almost always a prompt problem, not a node problem: you mentioned a background. Rewrite for the subject alone.

    Also: an unwired image output means the node never executes. It's not an output node, so nothing runs and nothing is charged - a common "why is there no error and no image" moment. Connect it to a preview or save node first.

    Use the right-click KIE Next · Check inputs & model controls menu when you want the documented limits without spending anything; it reads cached documentation fields locally and won't upload or submit.

    And the standing objection to every node in this pack: you cannot run this model at home, so an API call is the honest price, but that price recurs on every iteration. If your actual goal is a hundred images of the same character, a local checkpoint plus a small LoRA is cheaper by the end of the week.

    CategoryKIE Next/Image/Qwen

    Inputs (10)

    NameTypeDefaultDescription
    promptSTRINGA corgi wearing a yellow rain hat sitting on stone steps after the rain, shallow depth of fieldThe prompt that describes the image content, style and composition you want to generate. Required. Any language is supported, up to 5000 characters; if it is longer, the request is rejected.
    aspect_ratiooptCOMBO16:9The output aspect ratio. Default `1:1`. The actual pixel size also depends on `resolution`.
    resolutionoptCOMBO1KThe output resolution tier. `1K` is the faster option; `2K` produces four times the pixels and takes longer. Only `1K` and `2K` are accepted — with any other value, including `4K`, the request is rejected.
    backgroundoptCOMBOopaqueBackground type. transparent outputs a PNG or WebP with a real alpha channel and cannot be used with JPEG. When using transparent, describe only the subject — prompts that mention a background, scene, surface, etc. may produce a non-transparent result.
    output_formatoptCOMBOpngThe output image format. `png` (default) and `webp` both carry an alpha channel and can be used with `background: transparent`. `jpeg` has no alpha channel and cannot be combined with a transparent background.
    enhance_promptoptBOOLEANtrueRewrites the prompt into a fuller scene description before generating, which noticeably improves quality. Enabled by default (also when the parameter is omitted); pass false to turn it off.
    seedoptINT20260921-2147483648–2147483647The random seed. Omit it to generate with a random seed. Passing the same seed together with the same prompt and parameters reproduces the same image within the same service version.
    nsfw_checkeroptBOOLEANfalseDefaults to false. When false, no additional content filtering is applied and results are returned directly by the model.
    timeout_secondsoptINT120030–7200—
    callback_urloptSTRINGOptional KIE callback URL. Leave empty for normal ComfyUI use.

    Outputs (7)

    NameTypeDescription
    imageIMAGE—
    urlSTRING—
    all_urls_jsonSTRING—
    task_idSTRING—
    raw_jsonSTRING—
    credits_consumedFLOAT—
    credits_leftFLOAT—