Common Upload Errors and Solutions

Uploading to FFmpeg Micro uses a presigned URL flow. Here are the most common issues and how to fix them.

1. "SignatureDoesNotMatch" Error

This error means the upload request doesn't match the presigned URL signature.

Common Causes

Wrong Content-Type:

# ❌ WRONG - Content-Type doesn't match what you requested
curl -X PUT "$UPLOAD_URL" \
  -H "Content-Type: video/mpeg" \
  --data-binary @video.mp4

# ✅ CORRECT - matches the contentType from presigned URL request
curl -X PUT "$UPLOAD_URL" \
  -H "Content-Type: video/mp4" \
  --data-binary @video.mp4

Extra headers:

# ❌ WRONG - Authorization header not allowed on presigned URL
curl -X PUT "$UPLOAD_URL" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  --data-binary @video.mp4

# ✅ CORRECT - only Content-Type header
curl -X PUT "$UPLOAD_URL" \
  -H "Content-Type: video/mp4" \
  --data-binary @video.mp4

Solution

Only include the Content-Type header. The presigned URL already contains authentication.

2. "Expired Presigned URL"

Presigned upload URLs expire after 15 minutes.

Error Message

<Error>
  <Code>ExpiredToken</Code>
  <Message>The provided token has expired.</Message>
</Error>

Solution

Request a fresh presigned URL and upload immediately:

// ❌ WRONG - URL could expire
const { uploadUrl } = await getPresignedUrl()
await doSomethingElse()  // Takes 20 minutes...
await uploadFile(uploadUrl, file)  // Expired!

// ✅ CORRECT - upload immediately
const { uploadUrl } = await getPresignedUrl()
await uploadFile(uploadUrl, file)  // Within 15 minutes

3. "Network Timeout"

Large files can timeout if your connection is slow.

Solutions

1. Use resumable uploads (for files > 100MB):

// Request a resumable upload URL
const response = await fetch('/v1/upload/presigned-url', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    filename: 'large-video.mp4',
    contentType: 'video/mp4',
    fileSize: file.size,
    resumable: true  // ← Enable resumable uploads
  })
})

2. Compress before uploading:

# Compress video before upload (reduces size by ~50%)
ffmpeg -i input.mp4 -vcodec libx264 -crf 28 compressed.mp4

3. Upload in chunks (for very large files):

Contact support for multipart upload instructions.

4. "Invalid Bucket Permissions"

If you're uploading to your own bucket, you may see permission errors.

Solution

Use the FFmpeg Micro presigned upload flow instead of your own bucket. Or contact support to configure bucket permissions.

5. CORS Errors (Browser Uploads)

If you're uploading from a browser and see CORS errors:

Error Message

Access to fetch at 'https://storage.googleapis.com/...'
from origin 'https://your-app.com' has been blocked by CORS policy

Solution

The presigned URLs already include CORS headers. Make sure you're:

Using the exact uploadUrl from the API response

Not adding extra headers (like Authorization)

Using PUT method (not POST)

6. "File Too Large"

Each plan has file size limits:

Free: 500 MB per file

Starter: 2 GB per file

Professional: 10 GB per file

Enterprise: Custom limits

Solution

Upgrade your plan

Compress the video before uploading

Split long videos into segments

Best Practices

✅ Do This

Get presigned URL and upload immediately (within 15 minutes)

Use exact Content-Type from your presigned URL request

Let the HTTP client calculate Content-Length automatically

Confirm upload after completion

Handle errors and retry with exponential backoff

❌ Don't Do This

Don't cache presigned URLs (they expire)

Don't add Authorization header to presigned URL requests

Don't change file between requesting URL and uploading

Don't modify Content-Type between request and upload

Example: Robust Upload Flow

async function uploadVideo(file) {
  const maxRetries = 3
  let attempt = 0

  while (attempt < maxRetries) {
    try {
      // 1. Get presigned URL
      const urlResponse = await fetch('/v1/upload/presigned-url', {
        method: 'POST',
        headers: {
          'Authorization': 'Bearer YOUR_API_KEY',
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({
          filename: file.name,
          contentType: file.type,
          fileSize: file.size
        })
      })

      if (!urlResponse.ok) {
        throw new Error('Failed to get presigned URL')
      }

      const { uploadUrl, filename } = await urlResponse.json()

      // 2. Upload file (no auth header!)
      const uploadResponse = await fetch(uploadUrl, {
        method: 'PUT',
        headers: {
          'Content-Type': file.type
        },
        body: file
      })

      if (!uploadResponse.ok) {
        throw new Error('Upload failed: ' + uploadResponse.statusText)
      }

      // 3. Confirm upload
      await fetch('/v1/upload/confirm', {
        method: 'POST',
        headers: {
          'Authorization': 'Bearer YOUR_API_KEY',
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({
          filename: filename,
          fileSize: file.size
        })
      })

      return filename

    } catch (error) {
      attempt++
      if (attempt >= maxRetries) {
        throw error
      }
      // Exponential backoff: 2s, 4s, 8s
      await new Promise(resolve => setTimeout(resolve, 2000 * Math.pow(2, attempt)))
    }
  }
}

Still Having Issues?

Contact support at javid@ffmpeg-micro.com with:

The exact error message

The file size and type

Your API key (first 8 characters)

Browser/platform if relevant

Common Upload Errors and Solutions

Common Upload Errors and Solutions

1. "SignatureDoesNotMatch" Error

Common Causes

Solution

2. "Expired Presigned URL"

Error Message

Solution

3. "Network Timeout"

Solutions

4. "Invalid Bucket Permissions"

Solution

5. CORS Errors (Browser Uploads)

Error Message

Solution

6. "File Too Large"

Solution

Best Practices

✅ Do This

❌ Don't Do This

Example: Robust Upload Flow

Still Having Issues?

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