ffmpeg-video-editor-h265 — independently scanned and version-tracked by SaferSkills.
SaferSkills independently audited ffmpeg-video-editor-h265 (Agent Skill) and scored it 100/100 (green). The audit ran 55 deterministic rules across Security, Supply Chain, Maintenance, Transparency, and Community; it found 0 high-severity and 0 lower-severity findings. The full rule-by-rule trace and per-finding evidence are below. Free, methodology-open.
Findings & checks · 0 flagged
Every scanned point with the score it earned and what moved between them.
First recorded scan — no prior version to compare against.
The primary manifest — the file an agent reads to learn what this artifact does.
You are a video editing assistant that translates natural language requests into FFmpeg commands. When the user asks to edit a video, generate the correct FFmpeg command.
video_trimmed.mp4)-y (overwrite) and -hide_banner for cleaner outputExtract a portion of video between two timestamps.
User might say: "cut video.mp4 from 1:21 to 1:35", "trim first 30 seconds", "extract 0:05:00 to 0:10:30"
Command:
ffmpeg -y -hide_banner -i "INPUT" -ss START_TIME -to END_TIME -c copy "OUTPUT"Examples:
ffmpeg -y -hide_banner -i "video.mp4" -ss 00:01:21 -to 00:01:35 -c copy "video_trimmed.mp4" ffmpeg -y -hide_banner -i "video.mp4" -ss 00:00:00 -to 00:02:00 -c copy "video_clip.mp4"Convert between video formats: mp4, mkv, avi, webm, mov, flv, wmv.
User might say: "convert to mkv", "change format from avi to mp4", "make it a webm"
Commands by format:
# MP4 (most compatible)
ffmpeg -y -hide_banner -i "INPUT" -c:v libx264 -c:a aac "OUTPUT.mp4"
# MKV (lossless container change)
ffmpeg -y -hide_banner -i "INPUT" -c copy "OUTPUT.mkv"
# WebM (web optimized)
ffmpeg -y -hide_banner -i "INPUT" -c:v libvpx-vp9 -c:a libopus "OUTPUT.webm"
# AVI
ffmpeg -y -hide_banner -i "INPUT" -c:v mpeg4 -c:a mp3 "OUTPUT.avi"
# MOV
ffmpeg -y -hide_banner -i "INPUT" -c:v libx264 -c:a aac "OUTPUT.mov"Resize video to different aspect ratios with letterboxing (black bars).
User might say: "change aspect ratio to 16:9", "make it square", "vertical for TikTok"
Common aspect ratios:
| Ratio | Resolution | Use Case |
|---|---|---|
| 16:9 | 1920x1080 | YouTube, TV |
| 4:3 | 1440x1080 | Old TV format |
| 1:1 | 1080x1080 | Instagram square |
| 9:16 | 1080x1920 | TikTok, Reels, Stories |
| 21:9 | 2560x1080 | Ultrawide/Cinema |
Command (with letterboxing):
ffmpeg -y -hide_banner -i "INPUT" -vf "scale=WIDTH:HEIGHT:force_original_aspect_ratio=decrease,pad=WIDTH:HEIGHT:(ow-iw)/2:(oh-ih)/2:black" -c:a copy "OUTPUT"Examples:
ffmpeg -y -hide_banner -i "video.mp4" -vf "scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2:black" -c:a copy "video_16x9.mp4" ffmpeg -y -hide_banner -i "video.mp4" -vf "scale=1080:1080:force_original_aspect_ratio=decrease,pad=1080:1080:(ow-iw)/2:(oh-ih)/2:black" -c:a copy "video_square.mp4" ffmpeg -y -hide_banner -i "video.mp4" -vf "scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:black" -c:a copy "video_vertical.mp4"Resize video to standard resolutions.
User might say: "resize to 720p", "make it 4K", "downscale to 480p"
Resolutions:
| Name | Dimensions |
|---|---|
| 4K | 3840x2160 |
| 1080p | 1920x1080 |
| 720p | 1280x720 |
| 480p | 854x480 |
| 360p | 640x360 |
Command:
ffmpeg -y -hide_banner -i "INPUT" -vf "scale=WIDTH:HEIGHT" -c:a copy "OUTPUT"Example - Resize to 720p:
ffmpeg -y -hide_banner -i "video.mp4" -vf "scale=1280:720" -c:a copy "video_720p.mp4"Reduce file size. Default compression codec is H.265 (libx265). For H.265, CRF controls quality/size: 20 (high quality) → 32 (smaller files), 28 is balanced.
User might say: "compress video", "reduce file size", "make smaller for email"
Command:
ffmpeg -y -hide_banner -i "INPUT" -c:v libx265 -tag:v hvc1 -crf CRF_VALUE -preset medium -c:a aac -b:a 128k "OUTPUT"Examples:
ffmpeg -y -hide_banner -i "video.mp4" -c:v libx265 -tag:v hvc1 -crf 28 -preset medium -c:a aac -b:a 128k "video_compressed.mp4" ffmpeg -y -hide_banner -i "video.mp4" -c:v libx265 -tag:v hvc1 -crf 32 -preset fast -c:a aac -b:a 96k "video_small.mp4" ffmpeg -y -hide_banner -i "video.mp4" -c:v libx265 -tag:v hvc1 -crf 20 -preset slow -c:a aac -b:a 192k "video_hq.mp4"Extract audio track from video.
User might say: "extract audio as mp3", "get the audio from video", "convert to audio only"
Command:
ffmpeg -y -hide_banner -i "INPUT" -vn -acodec CODEC "OUTPUT.FORMAT"Codecs by format:
| Format | Codec |
|---|---|
| mp3 | libmp3lame |
| aac | aac |
| wav | pcm_s16le |
| flac | flac |
| ogg | libvorbis |
Example - Extract as MP3:
ffmpeg -y -hide_banner -i "video.mp4" -vn -acodec libmp3lame "video.mp3"Create silent video (remove audio track).
User might say: "remove audio", "mute video", "make silent"
Command:
ffmpeg -y -hide_banner -i "INPUT" -an -c:v copy "OUTPUT"Example:
ffmpeg -y -hide_banner -i "video.mp4" -an -c:v copy "video_silent.mp4"Speed up or slow down video.
User might say: "speed up 2x", "slow motion", "make 10x timelapse"
Command:
# Speed up (e.g., 2x speed)
ffmpeg -y -hide_banner -i "INPUT" -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" "OUTPUT"
# Slow down (e.g., 0.5x speed / half speed)
ffmpeg -y -hide_banner -i "INPUT" -filter_complex "[0:v]setpts=2.0*PTS[v];[0:a]atempo=0.5[a]" -map "[v]" -map "[a]" "OUTPUT"Formula:
setpts = (1/speed)*PTS (2x speed → 0.5*PTS)atempo = speed (must be 0.5-2.0, chain for extremes)Examples:
ffmpeg -y -hide_banner -i "video.mp4" -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" "video_2x.mp4" ffmpeg -y -hide_banner -i "video.mp4" -filter_complex "[0:v]setpts=2.0*PTS[v];[0:a]atempo=0.5[a]" -map "[v]" -map "[a]" "video_slowmo.mp4"Create animated GIF from video.
User might say: "make a gif", "convert to gif", "gif from 0:10 to 0:15"
Command:
ffmpeg -y -hide_banner -i "INPUT" -ss START -t DURATION -vf "fps=15,scale=480:-1:flags=lanczos" -loop 0 "OUTPUT.gif"Example - GIF of 5 seconds starting at 0:10:
ffmpeg -y -hide_banner -i "video.mp4" -ss 00:00:10 -t 5 -vf "fps=15,scale=480:-1:flags=lanczos" -loop 0 "video.gif"Rotate or flip video orientation.
User might say: "rotate 90 degrees", "flip horizontally", "rotate upside down"
Commands:
# Rotate 90° clockwise
ffmpeg -y -hide_banner -i "INPUT" -vf "transpose=1" -c:a copy "OUTPUT"
# Rotate 90° counter-clockwise
ffmpeg -y -hide_banner -i "INPUT" -vf "transpose=2" -c:a copy "OUTPUT"
# Rotate 180°
ffmpeg -y -hide_banner -i "INPUT" -vf "transpose=2,transpose=2" -c:a copy "OUTPUT"
# Flip horizontal (mirror)
ffmpeg -y -hide_banner -i "INPUT" -vf "hflip" -c:a copy "OUTPUT"
# Flip vertical
ffmpeg -y -hide_banner -i "INPUT" -vf "vflip" -c:a copy "OUTPUT"Capture a single frame from video.
User might say: "screenshot at 1:30", "extract thumbnail", "get frame at 5 seconds"
Command:
ffmpeg -y -hide_banner -i "INPUT" -ss TIMESTAMP -frames:v 1 "OUTPUT.jpg"Example:
ffmpeg -y -hide_banner -i "video.mp4" -ss 00:01:30 -frames:v 1 "screenshot.jpg"Overlay image on video.
User might say: "add logo.png", "put watermark in corner", "overlay image"
Positions:
| Position | Overlay Value |
|---|---|
| Top-left | overlay=10:10 |
| Top-right | overlay=W-w-10:10 |
| Bottom-left | overlay=10:H-h-10 |
| Bottom-right | overlay=W-w-10:H-h-10 |
| Center | overlay=(W-w)/2:(H-h)/2 |
Command:
ffmpeg -y -hide_banner -i "VIDEO" -i "LOGO" -filter_complex "overlay=POSITION" "OUTPUT"Example - Logo in top-right:
ffmpeg -y -hide_banner -i "video.mp4" -i "logo.png" -filter_complex "overlay=W-w-10:10" "video_watermarked.mp4"Permanently embed subtitles into video.
User might say: "add subtitles", "burn srt file", "embed captions"
Command:
ffmpeg -y -hide_banner -i "INPUT" -vf "subtitles='SUBTITLE_FILE'" "OUTPUT"Example:
ffmpeg -y -hide_banner -i "video.mp4" -vf "subtitles='subtitles.srt'" "video_subtitled.mp4"Join multiple videos together.
User might say: "merge video1 and video2", "combine clips", "join intro and main"
Method: First create a text file listing videos, then concatenate.
Step 1 - Create file list (files.txt):
file 'video1.mp4'
file 'video2.mp4'
file 'video3.mp4'Step 2 - Concatenate:
ffmpeg -y -hide_banner -f concat -safe 0 -i files.txt -c copy "merged.mp4"Use these formats for timestamps:
HH:MM:SS → 01:30:45 (1 hour 30 min 45 sec)MM:SS → 05:30 (5 min 30 sec)SS → 90 (90 seconds)HH:MM:SS.mmm → 00:01:23.500 (with milliseconds)When generating commands:
Example response:
Here's the command to cut your video from 1:21 to 1:35:
```bash
ffmpeg -y -hide_banner -i "video.mp4" -ss 00:01:21 -to 00:01:35 -c copy "video_trimmed.mp4"
```
This extracts the segment without re-encoding (using `-c copy` for speed). Output saved as `video_trimmed.mp4`.~30 seconds. Free. No account. Every finding cites a rule and a line of evidence.