gchq/CyberChef · error · OperationError

Error opening image file. (${err})

Error message

Error opening image file. (${err})

What it means

Thrown by NormaliseImage.run when Jimp.read(input) rejects. The magic-byte check (isImage) passed, but Jimp could not decode the buffer — typically because the file is truncated, has a valid header but corrupt body, or uses a sub-format Jimp does not support. The original error is interpolated into the message.

Source

Thrown at src/core/operations/NormaliseImage.mjs:47

        this.presentType = "html";
        this.args = [];
    }

    /**
     * @param {ArrayBuffer} input
     * @param {Object[]} args
     * @returns {byteArray}
     */
    async run(input, args) {
        if (!isImage(input)) {
            throw new OperationError("Invalid file type.");
        }

        let image;
        try {
            image = await Jimp.read(input);
        } catch (err) {
            throw new OperationError(`Error opening image file. (${err})`);
        }

        try {
            image.normalize();

            let imageBuffer;
            if (image.mime === "image/gif") {
                imageBuffer = await image.getBuffer(JimpMime.png);
            } else {
                imageBuffer = await image.getBuffer(image.mime);
            }
            return imageBuffer.buffer;
        } catch (err) {
            throw new OperationError(`Error normalising image. (${err})`);
        }
    }

    /**

View on GitHub (pinned to 4290ea7539)

Solutions

1. Re-obtain the source image from a known-good copy.
2. Open the file in an image editor and re-export to repair structure.
3. Inspect the interpolated err string for the specific Jimp failure.
4. If the format is unusual (WebP/HEIC), convert to PNG/JPG first with another tool.

try {
  await chef.bake("Normalise Image", [], input);
} catch (e) {
  if (e.message.startsWith("Error opening image file.")) {
    // re-export the source image, then retry
  } else throw e;
}

When it happens

Trigger: run(input, args) where isImage returns a MIME type but Jimp.read() throws asynchronously. Examples: a JPEG with a correct SOI marker but truncated scan data; a PNG missing IDAT; a GIF89a header with no image data; a WebP/HEIC that fooled the sniffer.

Common situations: Corrupt download; image truncated by a size limit; CMYK or exotic colour-space JPEG; progressive JPEG with missing segments; file that had its header patched to look like an image.

Related errors

• Error loading image. (${err})
• Error loading image. (${err})
• Error loading image. (${err})
• Error opening image. (${err})
• Error normalising image. (${err})

AI-assisted analysis of gchq/CyberChef@4290ea7539 (2026-08-13). Data as JSON: /api/errors/1e02e533a4639cb1. Report an issue: GitHub.