Anime & animation
Remediate rapid brightness changes and red flashes in animated sequences.
“Powerful” — David Revoy · CC BY 4.0 · Cropped to fit
Reduce the flashes.
Keep the video.
Detect hazardous flashing, remediate affected sequences, and preserve the rest of your video.
From a flash
to a finding.
See where the incidents occur—and which intervals were remediated.
Static preview · Demonstration data
For the videos
you actually make.
Animation, gameplay, a concert edit.
Find and remediate flashing in your MP4.
Gaming
Check gameplay footage before you share the highlights.
Music videos & edits
Find and remediate rapid lighting changes in concert recordings and edits.
Everyday video
Bring the same careful review to the videos you make every day.
Illustrative stills. FlashShield analyzes video over time; these images are not remediation results.
A report you
can work with.
Follow the incident from detection to the verification scan.
- Luminance analysis
- Find rapid changes in brightness, with timestamps for the affected intervals.
- Red-flash detection
- See red-flash incidents separately, alongside the luminance findings.
- Re-analysis after remediation
- Edited output is scanned again. A download is published only after an exact IRIS Pass.
How it works
- 01
Upload
Choose an MP4 to scan.
- 02
Analyze & remediate
Review findings. Request corrections.
- 03
Review & export
Download the verified result.
Choose your plan.
Start free. More room when you need it.
Basic
For users who only need to scan a few videos.
Free
- ✓MP4 uploads up to 50 MB
- ✓Up to 2 scans per day
- ✓Automatic flash detection
- ✓Targeted video remediation
- ✓Verified video download
- ✓Scan history
Plus
Designed for occasional users.
$9.99/month
- ✓Everything in Basic
- ✓MP4 uploads up to 500 MB
- ✓Up to 4 scans per day
- ✓Up to 5 GB retained media
- ✓Stripe subscription management
Most popular
Premium
For users processing video more often.
$19.99/month
- ✓Everything in Basic
- ✓MP4 uploads up to 1 GB
- ✓Up to 8 scans per day
- ✓Up to 10 GB retained media
- ✓Stripe subscription management
Prices are in USD. Paid plans renew monthly until canceled. Refunds & cancellationTerms & conditions
A few things
before you start.
Video flash checker FAQ
What does FlashShield detect?
FlashShield checks MP4 videos for potentially hazardous luminance and red-flash incidents using IRIS analysis. Timestamped reports help you find the affected moments.
Can I reduce flashing in an existing video?
Yes. After a scan, you can request targeted remediation of flagged intervals. FlashShield analyzes the edited output again and publishes an edited download only after an exact IRIS Pass.
Is there a free plan?
The Basic plan includes MP4 uploads up to 50 MB and up to two scans per day. Plus and Premium support larger files, more daily scans, and more retained media.
Does a passing scan guarantee viewer safety?
No. A pass means the video met the implemented scan thresholds. It is not a medical guarantee or a certification of accessibility compliance. Read about results and limitations.
A note from the builder
It started with a friend.
I began building FlashShield after becoming friends with someone who has photosensitive epilepsy. Watching a new episode of Death Note required precautions I had never considered.
At first, I focused on making the video pass the luminance test. But ghost frames and distorted colors made me reconsider what “working” should mean. I rebuilt the remediation around another question: would someone actually want to watch the result?
That is still the goal: helping people enjoy more of what they love, while taking both visual quality and flash reduction seriously. FlashShield remains an accessibility aid, not a guarantee of safety for every viewer.