Format Compatibility & Conversion Guide

Format Compatibility & Conversion Guide

Complete guide to media format support, codec recommendations, and conversion best practices.

Image Format Support

ImageMagick Formats

Raster Formats (Full Support):

• JPEG (.jpg, .jpeg) - Lossy, universal
• PNG (.png) - Lossless, transparency
• WebP (.webp) - Modern, lossy/lossless
• GIF (.gif) - Animation, limited colors
• TIFF (.tif, .tiff) - Professional, lossless
• BMP (.bmp) - Uncompressed, legacy
• ICO (.ico) - Icons, multi-size

Raw Formats (Read Support):

• CR2, NEF, ARW, DNG (Canon, Nikon, Sony, Adobe RAW)
• Requires dcraw or ufraw-batch

Vector Formats (Limited):

• SVG (.svg) - Read only, converts to raster
• PDF (.pdf) - Read/write, may have policy restrictions

Other Formats:

• HEIC (.heic) - Apple format, requires libheif
• AVIF (.avif) - Next-gen, requires libavif
• PSD (.psd) - Photoshop, basic support

FFmpeg Image Support

Input Formats:

• JPEG, PNG, BMP, TIFF, WebP, GIF
• Image sequences (frame_%04d.png)

Output Formats:

• JPEG, PNG, BMP, TIFF
• Video from images

Video Format Support

Container Formats

Universal Containers:

• MP4 (.mp4) - Most compatible, streaming
• MKV (.mkv) - Feature-rich, flexible
• WebM (.webm) - Web-optimized, open
• AVI (.avi) - Legacy, broad support
• MOV (.mov) - Apple, professional

Streaming Containers:

• TS (.ts) - Transport stream, HLS segments
• M3U8 (.m3u8) - HLS playlist
• MPD (.mpd) - DASH manifest
• FLV (.flv) - Flash (legacy)

Professional Formats:

• ProRes (.mov) - Apple professional
• DNxHD/DNxHR (.mxf, .mov) - Avid professional
• MXF (.mxf) - Broadcast

Video Codecs

Modern Codecs:

• H.264/AVC (libx264) - Universal, excellent balance
• H.265/HEVC (libx265) - Better compression, 4K
• VP9 (libvpx-vp9) - Open, YouTube
• AV1 (libaom-av1, libsvtav1) - Next-gen, best compression

Legacy Codecs:

• MPEG-4 (mpeg4) - Older devices
• MPEG-2 (mpeg2video) - DVD, broadcast
• VP8 (libvpx) - WebM predecessor

Professional Codecs:

• ProRes (prores) - Apple post-production
• DNxHD (dnxhd) - Avid editing
• Uncompressed (rawvideo) - Maximum quality

Audio Codecs

Modern Codecs:

• AAC (aac) - Universal, streaming
• Opus (libopus) - Best low-bitrate
• MP3 (libmp3lame) - Universal compatibility

Lossless Codecs:

• FLAC (flac) - Open, archival
• ALAC (alac) - Apple lossless
• WAV (pcm_s16le) - Uncompressed

Other Codecs:

• Vorbis (libvorbis) - Open, WebM
• AC-3 (ac3) - Dolby Digital, surround
• DTS (dts) - Cinema surround

Format Recommendations

Use Case Matrix

Platform Compatibility

Web Browsers (2025):

• Images: JPEG, PNG, WebP, GIF, SVG
• Video: MP4 (H.264), WebM (VP9), MP4 (AV1)
• Audio: AAC, MP3, Opus, Vorbis

Mobile Devices:

• iOS: JPEG, PNG, HEIC, MP4 (H.264/H.265), AAC
• Android: JPEG, PNG, WebP, MP4 (H.264/H.265), AAC

Smart TVs:

• Most: MP4 (H.264), AAC
• Modern: MP4 (H.265), AC-3

Social Media:

• All platforms: JPEG, MP4 (H.264), AAC

Quality vs Size Trade-offs

Image Quality Comparison

JPEG Quality Levels:

• 95-100: ~5-10 MB (large image), minimal artifacts
• 85-94: ~1-3 MB, imperceptible loss
• 75-84: ~500 KB-1 MB, slight artifacts
• 60-74: ~200-500 KB, visible artifacts
• Below 60: <200 KB, poor quality

Format Comparison (Same quality):

• WebP: 25-35% smaller than JPEG
• HEIC: 40-50% smaller than JPEG
• AVIF: 50-60% smaller than JPEG
• PNG: 2-5x larger than JPEG (lossless)

Video Quality Comparison

H.264 CRF Values:

• CRF 18: Visually lossless, ~8-15 Mbps (1080p)
• CRF 23: High quality, ~4-8 Mbps (1080p)
• CRF 28: Medium quality, ~2-4 Mbps (1080p)

Codec Comparison (Same quality):

• H.265: 40-50% smaller than H.264
• VP9: 30-40% smaller than H.264
• AV1: 50-60% smaller than H.264

Audio Quality Comparison

AAC Bitrates:

• 320 kbps: Transparent, archival
• 192 kbps: High quality, music
• 128 kbps: Good quality, streaming
• 96 kbps: Acceptable, low bandwidth
• 64 kbps: Poor, voice only

Codec Efficiency (Same quality):

• Opus: Best at low bitrates (<128k)
• AAC: Best overall balance
• MP3: Less efficient but universal

Conversion Best Practices

Image Conversions

PNG to JPEG:

# Standard conversion
magick input.png -quality 85 -strip output.jpg

# With transparency handling
magick input.png -background white -flatten -quality 85 output.jpg

JPEG to WebP:

# FFmpeg
ffmpeg -i input.jpg -quality 80 output.webp

# ImageMagick
magick input.jpg -quality 80 output.webp

RAW to JPEG:

# Requires dcraw
magick input.CR2 -quality 90 output.jpg

HEIC to JPEG:

# Requires libheif
magick input.heic -quality 85 output.jpg

Video Conversions

MKV to MP4:

# Copy streams (fast)
ffmpeg -i input.mkv -c copy output.mp4

# Re-encode if needed
ffmpeg -i input.mkv -c:v libx264 -crf 23 -c:a aac output.mp4

AVI to MP4:

# Modern codecs
ffmpeg -i input.avi -c:v libx264 -crf 23 -c:a aac output.mp4

MOV to MP4:

# Copy if H.264 already
ffmpeg -i input.mov -c copy output.mp4

# Convert ProRes to H.264
ffmpeg -i input.mov -c:v libx264 -crf 18 -c:a aac output.mp4

Any to WebM:

# VP9 encoding
ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 -c:a libopus output.webm

Audio Conversions

Extract Audio from Video:

# Keep original codec
ffmpeg -i video.mp4 -vn -c:a copy audio.m4a

# Convert to MP3
ffmpeg -i video.mp4 -vn -q:a 0 audio.mp3

# Convert to FLAC (lossless)
ffmpeg -i video.mp4 -vn -c:a flac audio.flac

Audio Format Conversion:

# WAV to MP3
ffmpeg -i input.wav -c:a libmp3lame -b:a 192k output.mp3

# MP3 to AAC
ffmpeg -i input.mp3 -c:a aac -b:a 192k output.m4a

# Any to Opus
ffmpeg -i input.wav -c:a libopus -b:a 128k output.opus

Codec Selection Guide

Choose H.264 When:

• Maximum compatibility needed
• Targeting older devices
• Streaming to unknown devices
• Social media upload
• Fast encoding required

Choose H.265 When:

• 4K video encoding
• Storage space limited
• Modern device targets
• Archival quality needed
• Bandwidth constrained

Choose VP9 When:

• YouTube upload
• Open-source requirement
• Chrome/Firefox primary
• Royalty-free needed

Choose AV1 When:

• Future-proofing content
• Maximum compression needed
• Encoding time not critical
• Modern platform targets

Format Migration Strategies

Archive to Web

# High-res archive -> Web-optimized
for img in archive/*.tif; do
  base=$(basename "$img" .tif)
  magick "$img" -resize 2000x2000\> -quality 85 -strip "web/${base}.jpg"
  magick "$img" -resize 2000x2000\> -quality 85 "web/${base}.webp"
done

Legacy to Modern

# Convert old formats to modern codecs
for video in legacy/*.avi; do
  base=$(basename "$video" .avi)
  ffmpeg -i "$video" \
    -c:v libx264 -crf 23 -preset slow \
    -c:a aac -b:a 128k \
    "modern/${base}.mp4"
done

Multi-Format Publishing

# Create multiple formats for compatibility
input="source.mp4"

# Modern browsers
ffmpeg -i "$input" -c:v libx264 -crf 23 -c:a aac output.mp4
ffmpeg -i "$input" -c:v libvpx-vp9 -crf 30 -c:a libopus output.webm

# Images
ffmpeg -ss 5 -i "$input" -vframes 1 poster.jpg
magick poster.jpg -quality 80 poster.webp

Troubleshooting

Unsupported Format

# Check FFmpeg formats
ffmpeg -formats

# Check ImageMagick formats
magick identify -list format

# Install missing codec support
sudo apt-get install libx264-dev libx265-dev libvpx-dev

Compatibility Issues

# Force compatible encoding
ffmpeg -i input.mp4 \
  -c:v libx264 -profile:v high -level 4.0 \
  -pix_fmt yuv420p \
  -c:a aac -b:a 128k \
  output.mp4

Quality Loss

# Avoid multiple conversions
# Bad: source -> edit -> web -> social
# Good: source -> final (single conversion)

# Use lossless intermediate
ffmpeg -i source.mp4 -c:v ffv1 intermediate.mkv
# Edit intermediate
ffmpeg -i intermediate.mkv -c:v libx264 final.mp4