SSC requires a recent passport-size photograph taken against a plain light background, without caps or dark glasses.
For One Time Registration you need a live captured photo; for each application the photo and signature must be in the format given in the notification.
The signature should be on white paper with black ink and match your usual signature.
The exact file size, dimensions and format are specified in the official SSC notification and can change between exams.
Applications with blurry or mismatched photos can be rejected, so upload carefully.