Black
Black at the start, at the end and inside the programme — where it begins and how long it lasts.
Deep Inspection
Every frame. Checked.
Metadata says what a file claims to be; Deep Inspection shows what it is. Media Inspector decodes every frame on your Mac's media engine, checks each one for what metadata can't tell you, and fingerprints the picture and sound — in about a minute for a feature film.
What it finds
Each frame is measured as it's decoded. Findings land on one timeline of the whole programme, summed up in one line — and each one is there for your policies, reports and shortcuts.
Frozen pictures
Pictures held still for two seconds or more — told apart from static shots, whose grain and noise keep moving.
Repeated frames
Duplicated frames and the real number of unique pictures per second: a 59.94 file that is really 29.97 doubled shows up at once.
Flash frames and shots
One- or two-frame shots left over at an edit, plus every shot change, the number of shots and the average shot length.
Interlacing and pulldown
Interlaced or progressive, top or bottom field first, and 3:2 pulldown — read from the pictures, so interlaced video flagged as progressive is caught (SD and HD, up to 30 frames per second).
Photosensitive flashing
General and red flashes per second across the picture — an indicative screen after ITU-R BT.1702 and Ofcom guidance that flags more than three flashes a second.
Decode errors
Damaged frames, one by one: a stretch the media engine rejects is decoded again in software, which pinpoints exactly the frames that are broken.
Picture fingerprint
A CRC32 of every decoded frame, sealed with SHA-256: the same picture in MP4 or Matroska gives the same fingerprint; change one frame and it changes.
Sound fingerprint
Every audio stream's decoded samples, fingerprinted: the same sound in WAV or QuickTime gives the same value, whatever the container.
A real feature film: 145,759 frames checked in 59 seconds, with four findings to review — flashing, freezes, flash frames and black inside the programme — each with its timecodes.
Frame previews
See the frames behind every finding
Hover the timeline and a card shows a finding's frames — for a flash frame, the frame before it, the flash frame and the frame after. Move into the card and click a frame to pin it beside the results.
- Step frame by frame with ← and →, or hover any moment of the programme
- Every frame shown is the exact frame Deep Inspection measured — its CRC32 is checked against the scan's, and the viewer says so
- Damaged frames are decoded again in software, so you see exactly what broke
Pinned: a flashing segment's frames in a filmstrip, each checked against the scan — step through them with ← and →, or play them with sound.
Playback
Play any finding, with sound
Play shows the seconds around a finding or a pinned frame in Media Inspector's own player, over a dimmed window. It uses the same decoder as the scan, so it plays every format the app reads — even ones your Mac can't play on its own.
- The finding's frames are marked as they pass
- The sound stays in sync with the picture, to within a millisecond
- Drag the playhead to scrub through the exact frames; Play picks up wherever you stop
On the media engine
A feature film in about a minute
Deep Inspection splits the stream at its keyframes and decodes the pieces in parallel on your Mac's media engine — the hardware video decoder — reading every frame straight from its memory. Every measurement runs on Accelerate, Apple's framework for vector math.
- Up to six VideoToolbox sessions decoding at once
- Every measurement on Accelerate (vDSP); fingerprints on the CPU's CRC32 and SHA-256 instructions
- 1 h 41 min of 720p H.264 — 145,759 frames — in 59 seconds on an M2 Pro
- Decoded in parallel or one piece after another, the results are identical
- You keep working while it runs; several files queue up and run one after another
Live progress: the stream is split at its keyframes and up to six media-engine sessions decode the pieces at once — you watch them fill in. Keep working, queue more files, or cancel at any time.
In your workflow
One click, then everywhere
Run it from the toolbar, from File ▸ Deep Inspection… (⌘I) or from the panel at the top of any Video tab. It explains what it will do first — with a “Don't show this again” box — then works while you do.
- Conformance policies — Picture Integrity and Flashing Content Screening (Indicative) are built in, and every finding can be a rule of your own
- QC Report — a Deep Inspection table beside the measured-vs-declared checks
- Comparison Report — whether two or three files carry the same picture and sound, or from which frame they differ
- Shortcuts — Check Conformance and Generate Report run Deep Inspection whenever a policy or a report needs it
Checked against known answers
Every result Deep Inspection gives is tested against files whose answers are known in advance — and against independent tools.
Known answers
Twenty-two test files made for the job — black, freezes, doubled frames, telecine, interlacing, flashing, corruption — each with an answer that follows from how it was made.
Independent cross-checks
Findings are cross-checked against FFmpeg's own detectors (blackdetect, freezedetect, idet, scdet), and every fingerprint matches an independent reference implementation.
No overclaiming
Flashing results are an indicative screen, not a certified test. H.264 and HEVC fingerprints are identical on every Mac; ProRes fingerprints depend on the decoder.
Frequently asked questions
Does Deep Inspection change my file?
No. It only reads and decodes — nothing is changed or written. The results stay in Media Inspector and in the reports you make from it.
How long does it take?
About a minute for a 1 h 41 min 720p film on an M2 Pro; 4K and older Macs take longer. You can keep working while it runs, follow its progress at the top of the Video tab, and cancel it at any time.
Which formats does it work with?
Every video Media Inspector opens. Formats your Mac's media engine decodes — H.264, HEVC and ProRes among them — run on it; anything else is decoded in software, with the same checks.
Is the flashing check a certified photosensitivity test?
No. It's an indicative screen after ITU-R BT.1702 and Ofcom guidance: it counts general and red flashes per second and flags more than three. Use it to catch problems early; where a certified test is required, you still need one.
Can it tell whether two files have the same content?
Yes. The picture and sound fingerprints depend only on the decoded essence, so the same picture in MP4 or Matroska — or the same sound in WAV or QuickTime — gives the same fingerprint. The Comparison Report puts it in words: identical, or different from frame N.
Where do I find it?
In the toolbar, in File ▸ Deep Inspection… (⌘I), and in the panel at the top of every Video tab. Select several files and they queue up and run one after another.
Can I see the frames behind a finding?
Yes. Hover the timeline to see a finding's frames, pin one and step through frame by frame, play the seconds around it with sound, or share any frame as a full-resolution PNG with its details. Every frame shown is checked against the CRC Deep Inspection measured.
Get Media Inspector
The complete media analyzer for your Mac — available now on the Mac App Store.
Requires macOS 14 (Sonoma) or later · Universal binary for Apple silicon and Intel