What does video validation check?

Postly checks supported media types, format, size and available duration and dimensions. A small, time-limited MP4/MOV header check can identify video encoding, reported frame rate and average bitrate. Other formats, metadata at the end of a file and unavailable headers remain unverified; codecs, audio, frame timing and peak bitrate are not fully verified. No video is converted, trimmed, cropped or re-encoded. Re-export incompatible files for the selected destination. Checks cannot guarantee provider acceptance.