Media Processing Skill

Process video, audio, and images using FFmpeg and ImageMagick command-line tools for conversion, optimization, streaming, and manipulation tasks.

When to Use This Skill

Use when:

Converting media formats (video, audio, images)
Encoding video with codecs (H.264, H.265, VP9, AV1)
Processing images (resize, crop, effects, watermarks)
Extracting audio from video
Creating streaming manifests (HLS/DASH)
Generating thumbnails and previews
Batch processing media files
Optimizing file sizes and quality
Applying filters and effects
Creating composite images or videos

Tool Selection Guide

FFmpeg: Video/Audio Processing

Use FFmpeg for:

Video encoding, conversion, transcoding
Audio extraction, conversion, mixing
Live streaming (RTMP, HLS, DASH)
Video filters (scale, crop, rotate, overlay)
Hardware-accelerated encoding
Media file inspection (ffprobe)
Frame extraction, concatenation
Codec selection and optimization

ImageMagick: Image Processing

Use ImageMagick for:

Image format conversion (PNG, JPEG, WebP, GIF)
Resizing, cropping, transformations
Batch image processing (mogrify)
Visual effects (blur, sharpen, sepia)
Text overlays and watermarks
Image composition and montages
Color adjustments, filters
Thumbnail generation

Decision Matrix

Task Tool Why

Video encoding FFmpeg Native video codec support

Audio extraction FFmpeg Direct stream manipulation

Image resize ImageMagick Optimized for still images

Batch images ImageMagick mogrify for in-place edits

Video thumbnails FFmpeg Frame extraction built-in

GIF creation FFmpeg or ImageMagick FFmpeg for video source, ImageMagick for images

Streaming FFmpeg Live streaming protocols

Image effects ImageMagick Rich filter library

Installation

macOS

brew install ffmpeg imagemagick

Ubuntu/Debian

sudo apt-get install ffmpeg imagemagick

Windows

Using winget

winget install ffmpeg winget install ImageMagick.ImageMagick

Or download binaries

FFmpeg: https://ffmpeg.org/download.html

ImageMagick: https://imagemagick.org/script/download.php

Verify Installation

ffmpeg -version ffprobe -version magick -version

or

convert -version

Quick Start Examples

Video Conversion

Convert format (copy streams, fast)

ffmpeg -i input.mkv -c copy output.mp4

Re-encode with H.264

ffmpeg -i input.avi -c:v libx264 -crf 22 -c:a aac output.mp4

Resize video to 720p

ffmpeg -i input.mp4 -vf scale=-1:720 -c:a copy output.mp4

Audio Extraction

Extract audio (no re-encoding)

ffmpeg -i video.mp4 -vn -c:a copy audio.m4a

Convert to MP3

ffmpeg -i video.mp4 -vn -q:a 0 audio.mp3

Image Processing

Convert format

magick input.png output.jpg

Resize maintaining aspect ratio

magick input.jpg -resize 800x600 output.jpg

Create square thumbnail

magick input.jpg -resize 200x200^ -gravity center -extent 200x200 thumb.jpg

Batch Image Resize

Resize all JPEGs to 800px width

mogrify -resize 800x -quality 85 *.jpg

Output to separate directory

mogrify -path ./output -resize 800x600 *.jpg

Video Thumbnail

Extract frame at 5 seconds

ffmpeg -ss 00:00:05 -i video.mp4 -vframes 1 -vf scale=320:-1 thumb.jpg

HLS Streaming

Generate HLS playlist

ffmpeg -i input.mp4
-c:v libx264 -preset fast -crf 22 -g 48
-c:a aac -b:a 128k
-f hls -hls_time 6 -hls_playlist_type vod
playlist.m3u8

Image Watermark

Add watermark to corner

magick input.jpg watermark.png -gravity southeast
-geometry +10+10 -composite output.jpg

Common Workflows

Optimize Video for Web

H.264 with good compression

ffmpeg -i input.mp4
-c:v libx264 -preset slow -crf 23
-c:a aac -b:a 128k
-movflags +faststart
output.mp4

Create Responsive Images

Generate multiple sizes

for size in 320 640 1024 1920; do magick input.jpg -resize ${size}x -quality 85 "output-${size}w.jpg" done

Extract Video Segment

From 1:30 to 3:00 (re-encode for precision)

ffmpeg -i input.mp4 -ss 00:01:30 -to 00:03:00
-c:v libx264 -c:a aac output.mp4

Batch Image Optimization

Convert PNG to optimized JPEG

mogrify -path ./optimized -format jpg -quality 85 -strip *.png

Video GIF Creation

High quality GIF with palette

ffmpeg -i input.mp4 -vf "fps=15,scale=640:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" output.gif

Image Blur Effect

Gaussian blur

magick input.jpg -gaussian-blur 0x8 output.jpg

Advanced Techniques

Multi-Pass Video Encoding

Pass 1 (analysis)

ffmpeg -y -i input.mkv -c:v libx264 -b:v 2600k -pass 1 -an -f null /dev/null

Pass 2 (encoding)

ffmpeg -i input.mkv -c:v libx264 -b:v 2600k -pass 2 -c:a aac output.mp4

Hardware-Accelerated Encoding

NVIDIA NVENC

ffmpeg -hwaccel cuda -i input.mp4 -c:v h264_nvenc -preset fast -crf 22 output.mp4

Intel QuickSync

ffmpeg -hwaccel qsv -c:v h264_qsv -i input.mp4 -c:v h264_qsv output.mp4

Complex Image Pipeline

Resize, crop, border, adjust

magick input.jpg
-resize 1000x1000^
-gravity center
-crop 1000x1000+0+0 +repage
-bordercolor black -border 5x5
-brightness-contrast 5x10
-quality 90
output.jpg

Video Filter Chains

Scale, denoise, watermark

ffmpeg -i video.mp4 -i logo.png
-filter_complex "[0:v]scale=1280:720,hqdn3d[v];[v][1:v]overlay=10:10"
-c:a copy output.mp4

Animated GIF from Images

Create with delay

magick -delay 100 -loop 0 frame*.png animated.gif

Optimize size

magick animated.gif -fuzz 5% -layers Optimize optimized.gif

Media Analysis

Inspect Video Properties

Detailed JSON output

ffprobe -v quiet -print_format json -show_format -show_streams input.mp4

Get resolution

ffprobe -v error -select_streams v:0
-show_entries stream=width,height
-of csv=s=x:p=0 input.mp4

Image Information

Basic info

identify image.jpg

Detailed format

identify -verbose image.jpg

Custom format

identify -format "%f: %wx%h %b\n" image.jpg

Performance Tips

Use CRF for quality control - Better than bitrate for video
Copy streams when possible - Avoid re-encoding with -c copy
Hardware acceleration - GPU encoding 5-10x faster
Appropriate presets - Balance speed vs compression
Batch with mogrify - In-place image processing
Strip metadata - Reduce file size with -strip
Progressive JPEG - Better web loading with -interlace Plane
Limit memory - Prevent crashes on large batches
Test on samples - Verify settings before batch
Parallel processing - Use GNU Parallel for multiple files

Reference Documentation

Detailed guides in references/ :

ffmpeg-encoding.md - Video/audio codecs, quality optimization, hardware acceleration
ffmpeg-streaming.md - HLS/DASH, live streaming, adaptive bitrate
ffmpeg-filters.md - Video/audio filters, complex filtergraphs
imagemagick-editing.md - Format conversion, effects, transformations
imagemagick-batch.md - Batch processing, mogrify, parallel operations
format-compatibility.md - Format support, codec recommendations

Common Parameters

FFmpeg Video

-c:v
Video codec (libx264, libx265, libvpx-vp9)
-crf
Quality (0-51, lower=better, 23=default)
-preset
Speed/compression (ultrafast to veryslow)
-b:v
Video bitrate (e.g., 2M, 2500k)
-vf
Video filters

FFmpeg Audio

-c:a
Audio codec (aac, mp3, opus)
-b:a
Audio bitrate (e.g., 128k, 192k)
-ar
Sample rate (44100, 48000)

ImageMagick Geometry

800x600
Fit within (maintains aspect)
800x600!
Force exact size
800x600^
Fill (may crop)
800x
Width only
x600
Height only
50%
Scale percentage

Troubleshooting

FFmpeg "Unknown encoder"

Check available encoders

ffmpeg -encoders | grep h264

Install codec libraries

sudo apt-get install libx264-dev libx265-dev

ImageMagick "not authorized"

Edit policy file

sudo nano /etc/ImageMagick-7/policy.xml

Change <policy domain="coder" rights="none" pattern="PDF" />

to <policy domain="coder" rights="read|write" pattern="PDF" />

Memory errors

Limit memory usage

ffmpeg -threads 4 input.mp4 output.mp4 magick -limit memory 2GB -limit map 4GB input.jpg output.jpg

Resources

FFmpeg: https://ffmpeg.org/documentation.html
FFmpeg Wiki: https://trac.ffmpeg.org/
ImageMagick: https://imagemagick.org/
ImageMagick Usage: https://imagemagick.org/Usage/