PNG to HEIC API#

The PNG to HEIC API converts a PNG image to HEIC (High Efficiency Image Container) format with a single request to POST /v1/convert/png-to-heic. Upload a .png file as multipart/form-data and receive raw HEIC bytes back, or set direct_download=false to get JSON metadata with a presigned download URL. Because HEIC does not support transparency, transparent areas in the PNG are composited onto a white background.


Endpoint#

POST /v1/convert/png-to-heic

Content-Type: multipart/form-data

Accepted input: .png files

Output format: .heic (image/heic)


Authentication#

Requires either a private API key or a JWT token from a public key.

X-API-Key: sk_your_private_key

Or:

Authorization: Bearer <jwt_token>

Request Parameters#

Parameter Type Required Default Description
file file Yes -- The .png image file to convert.
output_filename string No Input filename Custom output filename. The .heic extension is added automatically.
direct_download boolean No true When true, returns raw image bytes. When false, returns JSON metadata with a presigned download URL.

Conversion Details#

  • Uses Pillow with pillow-heif for HEIC encoding
  • If the PNG has an alpha channel (RGBA), transparent areas are composited onto a white background
  • Output quality is set to maximum (100)
Transparency note: HEIC does not support transparency. Any transparent areas in your PNG will appear white in the HEIC output.

Response#

Direct Download (direct_download=true, default)#

HTTP 200 OK
Content-Type: image/heic
Content-Disposition: inline; filename="image_20260405_123456789.heic"

Returns raw image bytes.

Metadata Response (direct_download=false)#

{
    "presigned_url": "https://spaces.example.com/...",
    "object_key": "env/files/{project_id}/png-to-heic/image_20260405_123456789.heic",
    "filename": "image_20260405_123456789.heic",
    "file_size": 45678,
    "conversion_time_seconds": 0.5
}

Code Examples#

Python#

import requests

with open("image.png", "rb") as f:
    response = requests.post(
        "https://api.enconvert.com/v1/convert/png-to-heic",
        headers={"X-API-Key": "sk_your_private_key"},
        files={"file": ("image.png", f)}
    )

with open("image_20260405_123456789.heic", "wb") as out:
    out.write(response.content)

Node.js#

const form = new FormData();
form.append("file", fs.createReadStream("image.png"));

const response = await fetch("https://api.enconvert.com/v1/convert/png-to-heic", {
    method: "POST",
    headers: { "X-API-Key": "sk_your_private_key" },
    body: form
});

fs.writeFileSync("image_20260405_123456789.heic", Buffer.from(await response.arrayBuffer()));

PHP#

$ch = curl_init("https://api.enconvert.com/v1/convert/png-to-heic");
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => ["X-API-Key: sk_your_private_key"],
    CURLOPT_POSTFIELDS => ["file" => new CURLFile("image.png")]
]);
$output = curl_exec($ch);
curl_close($ch);
file_put_contents("image_20260405_123456789.heic", $output);

Go#

body := &bytes.Buffer{}
writer := multipart.NewWriter(body)
part, _ := writer.CreateFormFile("file", "image.png")
file, _ := os.Open("image.png")
io.Copy(part, file)
writer.Close()

req, _ := http.NewRequest("POST", "https://api.enconvert.com/v1/convert/png-to-heic", body)
req.Header.Set("Content-Type", writer.FormDataContentType())
req.Header.Set("X-API-Key", "sk_your_private_key")
resp, _ := http.DefaultClient.Do(req)

Error Responses#

Status Condition
400 Bad Request File is not a .png file
400 Bad Request Image conversion failed (corrupt or unsupported file)
401 Unauthorized Missing or invalid API key / JWT token
402 Payment Required Monthly ops allowance exhausted
402 Payment Required Storage limit reached
413 Payload Too Large File exceeds plan's maximum file size

Limits#

Limit Value
Max file size Plan-dependent (Founding: 5 MB)
Output quality Maximum (not configurable)
Monthly conversions Plan-dependent

Frequently asked questions#

How do I convert PNG to HEIC with a REST API?#

Send a POST request to /v1/convert/png-to-heic with your .png file in a multipart/form-data body, authenticated via X-API-Key or a JWT Authorization: Bearer token. The converted HEIC is returned as raw image bytes by default.

What happens to PNG transparency when converting to HEIC?#

HEIC does not support transparency, so if the PNG has an alpha channel (RGBA), transparent areas are composited onto a white background in the HEIC output.

Can I control the HEIC output quality?#

No. Output quality is set to maximum (100) and is not configurable. Encoding uses Pillow with pillow-heif.

Can I get a download URL instead of raw HEIC bytes?#

Yes. Set direct_download=false and the API returns JSON metadata with a presigned_url, filename, file_size, and conversion_time_seconds.

Why does the API return 413 Payload Too Large?#

The uploaded file exceeds your plan's maximum file size (5 MB on the Founding plan).