TEMPORARY MEDIA WORKSPACE / VIDEO CROPPER
Center-crop a video to a common social aspect ratio while preserving proportions, then download the result as an H.264 MP4.
The processor required by this tool is available, and this worker can accept a temporary job.
Step 1 / source
Source intake
Choose a video whose important subject remains near the center of the frame.
Checking publication status before file selection...
The selected bytes are sent only to the Nirmion media API for this request. Processing uses a private temporary workspace rather than permanent catalogue storage.
Server-side source and result files are removed when the response stream closes. Re-downloads use the result Blob retained only in this browser tab.
Nirmion writes a separately named result containing nirmion_tools and never overwrites the selected source file.
Know the product contract
Every media page documents the accepted source, the selected FFmpeg transformation, the output container, and the limits that can affect the job.
Preview whether faces, captions, and moving subjects stay close enough to the center for an automatic crop.
FFmpeg calculates the largest centered rectangle matching the chosen ratio, removes the outer pixels, and encodes the remaining frame as H.264.
Watch the full result because a subject can move outside a centered crop later in the timeline.
Plain-language method
Cropping permanently removes edge pixels from the result. It does not intelligently track a subject or invent missing composition.
Preview whether faces, captions, and moving subjects stay close enough to the center for an automatic crop.
Choose 1:1 for square, 16:9 for landscape, 9:16 for vertical, or 4:5 for portrait feed posts.
Watch the full result because a subject can move outside a centered crop later in the timeline.
Useful when
Before processing
Container and codec
Output is H.264 MP4 with available audio encoded as AAC. The frame is cropped, not stretched or padded.
Know the boundary
The tool does not provide a movable crop box, keyframed subject tracking, or per-scene framing. Off-center content can be cut out.
Quick answers
These answers describe the actual upload, FFmpeg processing, download, and temporary-retention contract.
No. It removes outer pixels to reach the selected ratio while preserving proportions.
No. This bounded tool uses a centered crop.
Yes, when the source has audio it is encoded into the MP4.