Invalid file 'image': unsupported mimetype ('application/octet-stream'). Supported file formats are 'image/png'.

[ChiefGnome]

Confirm this is a Node library issue and not an underlying OpenAI API issue

• This is an issue with the Node library

Describe the bug

Since yesterday, a call to the "openai.images.edit" API throws an error:
BadRequestError: 400 Invalid file 'image': unsupported mimetype ('application/octet-stream'). Supported file formats are 'image/png'.
The same API call worked for that last year without this error.

To Reproduce

• Provide to images, and set the filenames to patchFn and maskFn, both files are PNGs.
• Call the openai.images.edit API with the following code

Code snippets

const response = await openai.images.edit({
        image: fs.createReadStream(patchFn),
        prompt,
        mask: fs.createReadStream(maskFn),
        n: 1,
        size: "1024x1024",
        response_format: "b64_json",
    }
);

OS

macOS 15.4

Node version

Node v22.14.0

Library version

openai 4.95.0

[aaronkopplin]

getting the same error

[SlicoHP]

Same error here with:

Node version
v20.9.0

Openai
4.93.0

[vemiliogp]

Getting the same error

[iMcreAtive]

Same error:
Node: v20.18.1
Openai: 4.95.1

[akinoavx13]

Hi,
Is there a fix available for this issue?
Thanks!

[jt55401]

same issue
node: v23.9.0
openai: 4.95.1

[kennethhutw]

Hi,
same issue
Is there a fix available for this issue? or sample code
Thanks!

[joeydotdev]

Seeing this across both go + node.js clients. Seems like a regression on OpenAI's side

[akinncar]

same issue

[devPablo]

Having the same issue on my end.
"openai": "^4.96.0"

[taufiq-husain]

Getting the same issue with this:

"engines": {
    "node": "22"
  },
"openai": "^4.96.0",

Might have to resort to CURL requests for now.

[dested]

Same error.

[kgmodi]

I am facing the same issue.

[Vadko]

temporary workaround if you are looking for immediate fix:

import { fileFromPath } from 'formdata-node/file-from-path';

const file = await fileFromPath(cachedFile, { type: 'image/jpeg' });

const response = await this.client.images.edit({
  model: 'gpt-image-1',
  prompt,
  n: 1,
  size: '1024x1024',
  image: file,
});

upd: I would recommend method below since it doesnt require any external library #1468 (comment)

[taufiq-husain]

temporary workaround if you are looking for immediate fix:

import { fileFromPath } from 'formdata-node/file-from-path';

const file = await fileFromPath(cachedFile, { type: 'image/jpeg' });

const response = await this.client.images.edit({
model: 'gpt-image-1',
prompt,
n: 1,
size: '1024x1024',
image: file,
});

This worked like a charm. Thank you very much!

[kennethhutw]

temporary workaround if you are looking for immediate fix:

import { fileFromPath } from 'formdata-node/file-from-path';

const file = await fileFromPath(cachedFile, { type: 'image/jpeg' });

const response = await this.client.images.edit({
model: 'gpt-image-1',
prompt,
n: 1,
size: '1024x1024',
image: file,
});

My files are on a remote host not locally
What should I do?

[Vadko]

temporary workaround if you are looking for immediate fix:
import { fileFromPath } from 'formdata-node/file-from-path';
const file = await fileFromPath(cachedFile, { type: 'image/jpeg' });
const response = await this.client.images.edit({
model: 'gpt-image-1',
prompt,
n: 1,
size: '1024x1024',
image: file,
});

My files are on a remote host not locally What should I do?

you can download file from remote host first using axios:

const response = await this.httpService.axiosRef<Readable>({
  url,
  method: 'GET',
  responseType: 'stream',
});

await new Promise<void>((resolve, reject) => {
  const writeStream = fs.createWriteStream(
    filepath
  );

  response.data.pipe(writeStream);

  writeStream.on('finish', resolve);
  writeStream.on('error', reject);
});

and after that you can pass filepath variable to fileFromPath function from comment above. dont forget to make cleanup after uploading image to openai with fs.unlinkSync(filepath) :)

[kennethhutw]

temporary workaround if you are looking for immediate fix:
import { fileFromPath } from 'formdata-node/file-from-path';
const file = await fileFromPath(cachedFile, { type: 'image/jpeg' });
const response = await this.client.images.edit({
model: 'gpt-image-1',
prompt,
n: 1,
size: '1024x1024',
image: file,
});

My files are on a remote host not locally What should I do?

you can download file from remote host first using axios:

const response = await this.httpService.axiosRef<Readable>({
  url,
  method: 'GET',
  responseType: 'stream',
});

await new Promise<void>((resolve, reject) => {
  const writeStream = fs.createWriteStream(
    filepath
  );

  response.data.pipe(writeStream);

  writeStream.on('finish', resolve);
  writeStream.on('error', reject);
});

and after that you can pass filepath variable to fileFromPath function from comment above. dont forget to make cleanup after uploading image to openai with fs.unlinkSync(filepath) :)

Sorry I didn't make myself clear, but in my case I can't save files locally. Thank for your answer.

 const response = await axios.get(imagePath, { responseType: 'arraybuffer' });
   const buffer = Buffer.from(response.data, 'binary');
 const file = new File([response], filename, { type: 'image/png' }); 

but not work.

[95gabor]

Here is my solution based on the official documentation:

import OpenAI, { toFile } from "openai";
import { createReadStream } from 'fs';
import { resolve } from 'path';

const prompt = 'something';

const result = await this.openAI.images.edit({
  model: 'gpt-image-1',
  image: await toFile(
    createReadStream(resolve(__dirname, './test/sample.png')),
    null,
    { type: 'image/png' },
  ),
  prompt,
  n: 1,
  size: '1024x1024',
  // response_format: 'b64_json',
});

console.log(result.data[0].b64_json);

[LeonMueller-OneAndOnly]

For people who have the same issue and want to send user uploaded images images (that dont live on the file system of your server) to the openai editing enpoint you can use following utilities from node-fetch:

import { Blob, File } from "node-fetch"

// referenceImages: { dataurl: string; mimeType: string }[]

const image: Uploadable[] = input.referenceImages.map((aImg, aIndex) => {
    return new File([dataURLtoBlob(aImg.dataurl)], `reference-image-${aIndex}`, {
      type: aImg.mimeType,
    })
 })

client_openAISdk.images.edit({
      model: "gpt-image-1",
      prompt: input.prompt,
      // @ts-ignore
      size: input.size,
      user: userIdentifier,
      quality: input.quality,
      n: input.countImagesToGenerate,
      background: input.enableTransparency ? "transparent" : "opaque",
      moderation: "low",
      image: image,
})

function dataURLtoBlob(dataurl: string) {
  // DataURL parsen
  const arr = dataurl.split(",")
  const mimeMatch = arr[0]!.match(/:(.*?);/)
  const mime = mimeMatch ? mimeMatch[1] : ""
  const bstr = atob(arr[1]!)
  let n = bstr.length
  const u8arr = new Uint8Array(n)
  while (n--) {
    u8arr[n] = bstr.charCodeAt(n)
  }

  return new Blob([u8arr], { type: mime })
}