Understanding File Formats
Chapter 5: Understanding File Formats
By now, you've made several recordings and noticed that SeaMeet saves files with names like recording.webm or you've seen other files ending in .mp3, .mp4, .wav, and more. But what do these letters mean? Why does one recording take up 2 MB while another takes up 200 MB? Why does your video sometimes not play on your friend's computer?
This chapter will demystify file formats, codecs, and all that technical jargon. We'll use everyday analogies to explain why files come in different formats, how they affect quality and size, and—most importantly—which format you should use for your specific needs.
The Basics: What is a File Format?
Let's start with a simple question: Why can't you put soup in a paper bag?
Because the container matters.
A paper bag is great for sandwiches but terrible for soup. You need a container that:
- Holds the contents properly
- Keeps things organized
- Works with how you'll use it
File formats are exactly the same. They're just containers for your audio and video.
The Container Analogy
Think of a file format like a shipping box:
The box (file format/container):
- Determines the shape and size limits
- Has a label (the .webm, .mp4, .mp3 extension)
- Holds everything together
What's inside the box (the actual data):
- Audio tracks (your voice, music)
- Video tracks (the screen recording)
- Metadata (time, date, recording info)
- Subtitles or captions (if any)
Different boxes for different purposes:
- MP3 box: Only holds audio (like a padded envelope for fragile items)
- MP4 box: Holds video + audio (like a sturdy shipping box)
- WebM box: Modern, efficient box for web content
- WAV box: Holds uncompressed audio (like a solid metal case—heavy but protective)
Audio Formats vs. Video Formats: What's the Difference?
This is where a lot of confusion happens. Let's clear it up once and for all.
Audio-Only Formats
These containers can only hold sound—no video, no images, just audio.
Common audio-only formats:
- MP3 (.mp3)
- WAV (.wav)
- FLAC (.flac)
- AAC/M4A (.m4a, .aac)
- OGG (.ogg)
- Opus (.opus)
Think of these as: Audio-only containers, like a music CD (remember those?) or a voice recorder.
When you see these formats:
- You know there's no video inside
- They only contain sound
- Usually smaller file sizes
Video Formats
These containers can hold both video and audio together.
Common video formats:
- MP4 (.mp4)
- WebM (.webm)
- MOV (.mov)
- MKV (.mkv)
- AVI (.avi)
Think of these as: Complete packages that can hold both the "movie" (video) and the "soundtrack" (audio).
When you see these formats:
- They might have video, audio, or both
- Usually larger file sizes
- More complex structure
The MP3 vs. MP4 Confusion
This is the #1 source of confusion:
MP3 = Audio only
- Like a music file on your phone
- Contains only sound
- Cannot hold video
- Example: A song from iTunes or Spotify
MP4 = Video + Audio
- Like a movie or YouTube video
- Contains both picture and sound
- Can also hold just audio (confusing, we know!)
- Example: A YouTube download, a movie file
Simple way to remember:
- MP3 = "MPEG-1 Audio Layer 3" = Audio only
- MP4 = "MPEG-4 Part 14" = Video container
Analogy:
- MP3 is like a cassette tape (audio only)
- MP4 is like a DVD (can have video + audio)
Understanding Codecs: The Secret Ingredient
Now we need to talk about something called a codec. This is where it gets a bit technical, but we'll make it simple.
What is a Codec?
Codec = Coder + Decoder
A codec is like a translator that:
- Encodes (compresses) your recording into a smaller size when saving
- Decodes (decompresses) it back when playing
The compression analogy:
Imagine you have a huge pile of clothes (your raw recording). You have two options:
Option 1: No compression (WAV, uncompressed)
- Throw everything in a suitcase as-is
- Takes up the whole suitcase
- When you open it, everything is exactly as you left it
- Perfect quality, but huge size
Option 2: Compression (MP3, AAC, Opus)
- Fold everything neatly and vacuum-seal it
- Takes up 1/10th of the suitcase
- When you open it, clothes are mostly the same
- Some tiny wrinkles (quality loss), but much more efficient
Codecs are the folding method—different codecs fold (compress) in different ways, with different trade-offs between size and quality.
Common Audio Codecs Explained
MP3 (MPEG-1 Audio Layer 3)
What it is: The most famous audio codec Age: Invented in 1993 (over 30 years old!) Quality: Good for music, acceptable for voice Compression: Makes files about 10x smaller
Best for:
- Music
- Podcasts
- Wide compatibility (plays everywhere)
The trade-off:
- Small file size ✓
- Slight quality loss (especially at lower bitrates)
Why it's everywhere: MP3 became the standard because it was the first format to make music files small enough to share over slow internet connections in the 1990s.
AAC (Advanced Audio Coding)
What it is: The successor to MP3 Age: Invented in 1997 Quality: Better than MP3 at the same file size Compression: More efficient than MP3
Best for:
- Apple's ecosystem (iPhone, iTunes)
- Streaming (YouTube, Netflix use this)
- Voice recordings
Why it's better than MP3:
- Same quality at smaller file sizes
- Better for speech and voice
- Modern standard
Where you see it:
- Apple Music
- YouTube audio
- Most streaming services
- Files ending in .m4a or .aac
Opus
What it is: The most modern, efficient audio codec Age: Released in 2012 Quality: Excellent, especially for speech Compression: Very efficient—small files, great quality
Best for:
- Voice and speech
- Video calls
- Streaming
- When quality AND size matter
Why SeaMeet uses Opus:
- Perfect for voice recordings
- Excellent compression
- Free and open standard (no licensing fees)
- Works great with the WebM container
The secret sauce: Opus is "smart"—it automatically adjusts compression based on what's being recorded. Voice gets one type of compression, music gets another.
WAV (Waveform Audio File Format)
What it is: Uncompressed, raw audio Age: Invented in 1991 Quality: Perfect—no compression at all File size: HUGE (10x larger than MP3)
Best for:
- Professional audio editing
- Archiving original recordings
- When quality is more important than size
- Audio production
Why use it:
- Zero quality loss
- Easy to edit
- Industry standard for professionals
Why avoid it:
- Files are enormous
- Not practical for sharing
- Overkill for most uses
Think of it as: A RAW photo vs. a JPEG—maximum quality, maximum size.
FLAC (Free Lossless Audio Codec)
What it is: Compressed but lossless (perfect quality) Age: Released in 2001 Quality: Perfect—no quality loss File size: About half the size of WAV
Best for:
- Audiophiles
- Music archiving
- When you want perfect quality but reasonable size
The magic: FLAC is like a ZIP file for audio—it makes files smaller without losing any quality. When you "unzip" it, you get back exactly what you started with.
Where you see it:
- High-quality music downloads
- Audiophile collections
- Archiving important recordings
OGG Vorbis
What it is: Open-source alternative to MP3 Age: Released in 2000 Quality: Similar to MP3 Compression: Efficient
Best for:
- Open-source projects
- When you want to avoid proprietary formats
- Gaming audio
Note: Often confused with OGG Opus (which is different and better for voice).
Audio Codec Comparison
| Codec | File Size | Quality | Best For | Compatibility |
|---|---|---|---|---|
| Opus | Very Small | Excellent | Voice, streaming, meetings | Good (modern) |
| AAC | Small | Very Good | Music, general use | Excellent |
| MP3 | Small | Good | Universal compatibility | Universal |
| FLAC | Medium | Perfect | Archiving, music | Good |
| WAV | Huge | Perfect | Professional editing | Excellent |
| OGG | Small | Good | Open-source projects | Moderate |
Understanding Video Codecs
Video is more complex than audio because there's more data. A video codec has to compress thousands of images (frames) per minute.
Common Video Codecs Explained
VP9
What it is: Modern, efficient video codec Created by: Google Quality: Excellent Compression: Very efficient
Best for:
- YouTube (YouTube uses VP9 for most videos)
- Web streaming
- High-quality video at reasonable file sizes
- 4K and HD content
Why it's great:
- Same quality as H.264 but smaller files
- Free and open (no licensing fees)
- Excellent for streaming
Where you see it:
- Inside WebM files
- YouTube videos
- Modern browsers
VP8
What it is: Predecessor to VP9 Created by: Google Quality: Good Compression: Good
Best for:
- Fallback when VP9 isn't available
- Older devices
- Web video
Status: Being replaced by VP9, but still widely supported.
H.264 (AVC)
What it is: The most widely supported video codec Age: Released in 2003 Quality: Very good Compression: Good
Best for:
- Maximum compatibility
- Playing on any device
- Sharing with others
- Professional video
Why it's everywhere:
- Works on virtually every device
- Industry standard for over a decade
- Used in Blu-ray, streaming, broadcasting
The downside:
- Requires licensing fees (manufacturers pay)
- Not as efficient as newer codecs (VP9, H.265)
Where you see it:
- Inside MP4 files
- YouTube
- Netflix
- iPhone videos
- DVDs and Blu-ray
H.265 (HEVC)
What it is: Successor to H.264 Age: Released in 2013 Quality: Excellent Compression: 50% smaller than H.264 at same quality
Best for:
- 4K video
- When file size is critical
- High-quality streaming
The trade-off:
- Better compression than H.264
- But less compatible with older devices
- Higher licensing costs
Where you see it:
- iPhone 4K recordings
- Some streaming services
- Inside MKV files
AV1
What it is: The future of video codecs Age: Released in 2018 Quality: Excellent Compression: Better than VP9 and H.265
Best for:
- The future of streaming
- Maximum efficiency
- When you want the best compression
Current status:
- Very new
- Limited support on older devices
- YouTube and Netflix are starting to use it
Video Codec Comparison
| Codec | File Size | Quality | Compatibility | Best For |
|---|---|---|---|---|
| VP9 | Small | Excellent | Good (modern) | Web, YouTube, streaming |
| H.264 | Medium | Very Good | Universal | Sharing, compatibility |
| H.265 | Very Small | Excellent | Moderate | 4K, when size matters |
| VP8 | Medium | Good | Good | Fallback, older devices |
| AV1 | Very Small | Excellent | Limited (new) | Future-proofing |
Understanding Containers (File Formats)
Now that you understand codecs, let's talk about containers. Remember: the container is the box, the codec is what's inside.
Why Containers Matter
Different containers can hold different combinations of codecs. Some are flexible, some are restrictive.
Analogy:
- A shipping container (like on cargo ships) can hold almost anything
- A jewelry box is designed specifically for jewelry
- A CD case only holds CDs
Audio/video containers work the same way.
Audio-Only Containers
MP3 Container (.mp3)
What it holds: MP3 audio only Can it hold video? No Can it hold other codecs? No, only MP3
Think of it as: A dedicated MP3 player—only plays MP3s.
Why use it:
- Universal compatibility
- Simple and straightforward
- Everything supports it
WAV Container (.wav)
What it holds: Uncompressed audio (PCM) Can it hold video? No Can it hold other codecs? Yes, but usually uncompressed
Think of it as: A professional storage vault—holds audio in its purest form.
Why use it:
- Professional editing
- No quality loss
- Easy to work with
FLAC Container (.flac)
What it holds: FLAC compressed audio Can it hold video? No Can it hold other codecs? No, only FLAC
Think of it as: A compressed vault—perfect quality, smaller size.
M4A Container (.m4a)
What it holds: AAC audio (usually) Can it hold video? No (that's MP4) Can it hold other codecs? Technically yes, but usually AAC
Think of it as: Apple's preferred audio box.
Why use it:
- Apple's ecosystem
- Better than MP3
- Good compression
Video Containers
WebM Container (.webm)
What it holds:
- Video: VP8, VP9, or AV1
- Audio: Opus or Vorbis
Can it hold H.264? No Can it hold MP3? No
Think of it as: The modern, efficient web video box.
Why SeaMeet uses WebM:
- Excellent compression (small files)
- High quality
- Free and open (no licensing)
- Perfect for voice + screen recordings
- Works great in web browsers
Compatibility:
- ✓ Chrome, Firefox, Edge (excellent)
- ✓ VLC Media Player
- ✓ Modern media players
- ✗ Windows Media Player (may need codec)
- ✗ QuickTime (older versions)
The trade-off:
- Great for modern devices
- May need VLC for older Windows computers
MP4 Container (.mp4)
What it holds:
- Video: H.264, H.265, or others
- Audio: AAC, MP3, or others
Can it hold VP9? Technically yes, but rarely used
Think of it as: The universal video box—works everywhere.
Why it's popular:
- Universal compatibility
- Works on every device
- Standard for sharing
- iPhone and Android native support
Where you see it:
- YouTube downloads
- iPhone recordings
- Shared videos
- Professional video
MOV Container (.mov)
What it holds:
- Video: Various codecs (often H.264)
- Audio: Various codecs
Think of it as: Apple's video box.
Why use it:
- Apple's native format
- Professional video editing
- Good for Mac workflows
Note: Modern MOV files are very similar to MP4. Many MOV files will play on any device.
MKV Container (.mkv)
What it holds: Almost anything!
- Video: H.264, H.265, VP9, VP8, etc.
- Audio: MP3, AAC, FLAC, Opus, etc.
- Subtitles: Multiple languages
- Chapters: Like DVD chapters
Think of it as: The Swiss Army knife of video containers.
Why it's powerful:
- Can hold multiple audio tracks (English, Spanish, etc.)
- Can hold multiple subtitle tracks
- Can hold chapters
- Very flexible
The downside:
- Less compatible than MP4
- Some devices won't play MKV natively
- Better for storage than sharing
Best for:
- Archiving movies with multiple languages
- Storing videos with subtitles
- When you need maximum flexibility
Container Comparison
| Container | Video Codecs | Audio Codecs | Flexibility | Compatibility | Best For |
|---|---|---|---|---|---|
| WebM | VP8, VP9, AV1 | Opus, Vorbis | Low | Good (modern) | Web, SeaMeet recordings |
| MP4 | H.264, H.265 | AAC, MP3 | Medium | Universal | Sharing, universal use |
| MKV | Any | Any | Very High | Moderate | Archiving, multiple tracks |
| MOV | Various | Various | Medium | Good | Apple ecosystem |
Why SeaMeet Uses WebM
You've probably noticed that SeaMeet saves recordings as .webm files. Let's explain why.
The WebM Advantage
1. Perfect for Voice WebM uses the Opus audio codec, which is excellent for speech and voice recordings. It's like having a codec specifically designed for meetings and conversations.
2. Efficient Compression WebM with VP9 video and Opus audio creates files that are:
- Smaller than MP4 with H.264
- Better quality than MP4 at the same size
- Perfect for screen recordings
3. Free and Open WebM is completely free:
- No licensing fees
- No patents to worry about
- Anyone can use it
- Open source
4. Modern and Web-Friendly WebM was designed for the web:
- Works great in browsers
- Streams efficiently
- Perfect for uploading to web platforms
5. Great for Screen Recording VP9 (the video codec in WebM) is particularly good at:
- Recording text and UI elements clearly
- Compressing screen content efficiently
- Preserving sharp edges and details
The WebM Trade-Off
Compatibility consideration: While WebM is excellent, it's not as universally supported as MP4:
Works great with:
- ✓ Google Chrome
- ✓ Mozilla Firefox
- ✓ Microsoft Edge
- ✓ VLC Media Player
- ✓ Modern Android devices
- ✓ Most modern media players
May have issues with:
- ✗ Windows Media Player (old versions)
- ✗ QuickTime Player
- ✗ Some older devices
- ✗ iPhone (without third-party apps)
The solution: If you need to share with someone who can't play WebM, you can:
- Ask them to install VLC (free, plays everything)
- Convert to MP4 (see conversion section below)
- Upload to YouTube or similar (which handles the format)
Which Format Should You Use?
This is the practical question. Here's a simple guide:
For Audio Recordings
Sharing with anyone (maximum compatibility): → MP3
- Plays on everything
- Small file size
- Good quality
Apple ecosystem (iPhone, Mac, iTunes): → M4A (AAC)
- Native Apple support
- Better quality than MP3
- Efficient
Archiving (keeping the best quality): → FLAC
- Perfect quality
- Reasonable size
- Future-proof
Professional editing: → WAV
- No compression
- Easy to edit
- Maximum quality
For Video Recordings
Sharing with anyone (maximum compatibility): → MP4 with H.264
- Plays on every device
- iPhone compatible
- Universal standard
Uploading to web/YouTube: → MP4 or WebM
- Both work great
- YouTube accepts both
- Efficient streaming
Best quality, reasonable size: → WebM with VP9 (what SeaMeet uses)
- Excellent compression
- Great quality
- Modern standard
Archiving with multiple audio tracks: → MKV
- Can hold multiple languages
- Flexible
- Future-proof
iPhone/Mac workflows: → MOV
- Native Apple support
- Works seamlessly
- Good quality
Converting Between Formats
Sometimes you need to change a file from one format to another. Here's how.
When to Convert
Convert WebM to MP4 when:
- Sharing with someone who can't play WebM
- Uploading to a platform that prefers MP4
- Need iPhone compatibility
Convert to MP3 when:
- You only need the audio
- Want smaller files
- Need maximum compatibility
Convert WAV to FLAC when:
- Want to save space
- Don't need to edit further
- Archiving
How to Convert
Option 1: Use SeaMeet's Built-in Features (If Available)
Some versions of SeaMeet can export in different formats:
- Select your recording
- Look for "Export" or "Convert" option
- Choose your desired format
- Save the new file
Option 2: Use VLC Media Player (Free)
VLC can convert almost anything:
Steps:
- Download VLC (free from videolan.org)
- Open VLC
- Go to Media → Convert/Save
- Add your file
- Click "Convert/Save"
- Choose the output format (MP4, MP3, etc.)
- Choose destination
- Click Start
Pros:
- Completely free
- Works with virtually any format
- Reliable
Cons:
- Can be slow
- Interface is a bit technical
Option 3: Online Converters
Websites that convert files for you:
Popular options:
- CloudConvert
- Convertio
- Online-Convert
Steps:
- Go to the website
- Upload your file
- Choose output format
- Wait for conversion
- Download the result
Pros:
- Easy to use
- No software to install
- Fast for small files
Cons:
- Privacy concerns (you're uploading to a server)
- File size limits
- Requires internet
Privacy tip: Don't upload sensitive recordings to online converters. Use VLC or desktop software for confidential content.
Option 4: Desktop Software
For Windows/Mac:
- HandBrake (free, excellent for video)
- Freemake Video Converter (free version available)
- Any Video Converter
- Adobe Media Encoder (professional, paid)
For Audio Only:
- Audacity (free, excellent audio editor)
- XLD (Mac, for lossless audio)
- dBpoweramp (Windows, comprehensive)
Converting SeaMeet WebM to MP4
Since you'll likely need to convert WebM to MP4 for sharing, here's a specific guide:
Using VLC:
- Open VLC
- Media → Convert/Save
- Add your .webm file
- Click Convert/Save button
- In "Profile" dropdown, choose:
- "Video - H.264 + MP3 (MP4)" for video
- "Audio - MP3" for audio only
- Choose destination file (make sure it ends in .mp4)
- Click Start
- Wait for conversion
Quality note: Converting always has some quality loss. It's like making a photocopy of a photocopy. Try to keep the original WebM as your "master" copy.
Understanding File Extensions
File extensions (the letters after the dot) tell you what format a file is in. Here's what they mean:
Audio Extensions
| Extension | Format | Container/Codec | Type |
|---|---|---|---|
| .mp3 | MP3 | MP3 audio | Audio only |
| .wav | WAV | Uncompressed PCM | Audio only |
| .flac | FLAC | FLAC compressed | Audio only |
| .m4a | M4A | AAC audio | Audio only |
| .aac | AAC | AAC audio | Audio only |
| .ogg | OGG | Vorbis audio | Audio only |
| .opus | Opus | Opus audio | Audio only |
| .wma | WMA | Windows Media Audio | Audio only |
Video Extensions
| Extension | Format | Container | Video Codec | Audio Codec |
|---|---|---|---|---|
| .webm | WebM | WebM | VP8/VP9/AV1 | Opus/Vorbis |
| .mp4 | MP4 | MPEG-4 | H.264/H.265 | AAC/MP3 |
| .mov | MOV | QuickTime | Various | Various |
| .mkv | MKV | Matroska | Any | Any |
| .avi | AVI | AVI | Various | Various |
| .wmv | WMV | Windows Media | WMV | WMA |
| .flv | FLV | Flash | H.264 | AAC/MP3 |
Technical Deep Dive: How Compression Works
For those curious about the technical side, here's a simple explanation of how audio and video compression works.
Audio Compression
What gets removed:
1. Frequencies humans can't hear
- Very high pitches (above 20 kHz)
- Very low pitches (below 20 Hz)
- Most adults can't hear these anyway
2. Sounds masked by louder sounds
- If a loud drum hits, you won't hear a quiet whisper at the same moment
- The codec removes the "inaudible" whisper
3. Redundant information
- Silence uses almost zero data
- Repetitive sounds are stored efficiently
The result:
- MP3 removes about 90% of the data
- But sounds virtually the same to human ears
- Like removing every 10th page from a book—you can still read the story
Video Compression
What gets removed:
1. Spatial redundancy (within a frame)
- A blue sky has millions of blue pixels
- Instead of describing each one, the codec says "this area is blue"
- Like saying "the next 100 pixels are the same color"
2. Temporal redundancy (between frames)
- Video at 30 fps has similar frames
- Frame 1 and Frame 2 might be 95% the same
- The codec only stores the 5% that changed
- Like animation cels—only the moving parts are redrawn
3. Imperceptible details
- Tiny details you wouldn't notice
- Colors in shadows
- Subtle textures
The result:
- VP9 can compress video 100:1 or more
- A 2GB raw video becomes 20MB
- With minimal visible quality loss
Bitrate: The Quality Control
Bitrate is a key concept that determines quality and file size.
What is Bitrate?
Simple definition: How much data is used per second of audio or video.
Measured in:
- kbps (kilobits per second) for audio
- Mbps (megabits per second) for video
Analogy: Think of bitrate like water flowing through a pipe:
- High bitrate = Fire hose (more water/data, better quality, bigger files)
- Low bitrate = Garden hose (less water/data, lower quality, smaller files)
Audio Bitrates
| Bitrate | Quality | Use Case | File Size (3 min song) |
|---|---|---|---|
| 64 kbps | Poor | Voice calls only | ~1.4 MB |
| 128 kbps | Acceptable | Standard MP3 | ~2.8 MB |
| 192 kbps | Good | Better MP3 | ~4.2 MB |
| 256 kbps | Very Good | High-quality MP3 | ~5.6 MB |
| 320 kbps | Excellent | Best MP3 | ~7 MB |
| 1411 kbps | Perfect | CD quality (uncompressed) | ~30 MB |
| Lossless | Perfect | FLAC (varies) | ~15-25 MB |
What bitrate should you use?
For voice recordings:
- 64-96 kbps (Opus codec) = Excellent quality, tiny files
- 128 kbps (MP3) = Good quality, small files
- 192+ kbps = Overkill for voice
For music:
- 192 kbps (MP3) = Good, acceptable quality
- 256-320 kbps (MP3) = Very good to excellent
- Lossless (FLAC) = Perfect, for archiving
Video Bitrates
| Quality | Bitrate | File Size (1 min) |
|---|---|---|
| 480p @ 30fps | 2.5 Mbps | ~18 MB |
| 720p @ 30fps | 5 Mbps | ~35 MB |
| 1080p @ 30fps | 8 Mbps | ~60 MB |
| 1080p @ 60fps | 16 Mbps | ~120 MB |
| 4K @ 30fps | 35 Mbps | ~260 MB |
Note: These are typical bitrates for H.264/VP9 at good quality. Actual bitrates vary based on content complexity.
Common Questions About Formats
"Should I convert all my WebM files to MP4?"
No, not necessarily. Keep WebM as your archive format (it's higher quality and more efficient). Convert copies to MP4 only when you need to share with someone who can't play WebM.
Think of it like:
- WebM = Your original negatives (keep safe, best quality)
- MP4 = The prints you share (for compatibility)
"Why is my WAV file 50x bigger than my MP3?"
Because WAV is uncompressed. It's keeping every single bit of audio data. MP3 removes data that human ears can't hear or don't notice. It's like the difference between:
- A detailed architectural blueprint (WAV)
- A photograph of the building (MP3)
Both show the building, but the blueprint has way more detail.
"Will converting MP3 to WAV improve quality?"
No. Once quality is lost (by compressing to MP3), you can't get it back by converting to WAV. It's like trying to restore a compressed JPEG back to a RAW photo—the detail is gone forever.
Rule: Always keep your highest quality original. Downgrade copies for sharing, not the master.
"Why won't my iPhone play WebM files?"
Apple devices natively prefer their own formats (MOV, M4A). While modern iOS versions can play some WebM files in Safari, the native Photos app and older devices may struggle.
Solutions:
- Convert to MP4 for iPhone
- Use VLC app on iPhone (plays everything)
- Upload to cloud and stream
"Is MP4 better quality than WebM?"
Not necessarily. Quality depends on:
- The codec used inside
- The bitrate/settings
- The source material
A WebM with VP9 at high bitrate can look better than an MP4 with H.264 at low bitrate.
The real difference: Compatibility. MP4 works everywhere. WebM works on modern devices and browsers.
"What format should I use for archiving?"
For maximum future-proofing:
- Video: MKV (most flexible) or MP4 (most compatible)
- Audio: FLAC (perfect quality, reasonable size)
For practical archiving:
- Keep SeaMeet's WebM files—they're high quality
- Make MP4 copies for compatibility
- Store on multiple drives/cloud
Best Practices Summary
The Golden Rules
-
Keep originals
- Never delete your original recording
- Make copies in other formats for sharing
- Original = highest quality version
-
Choose format based on purpose
- Archiving? → WebM, MKV, FLAC
- Sharing? → MP4, MP3
- Editing? → WAV, high-bitrate formats
-
Don't convert unnecessarily
- Every conversion loses some quality
- Convert once, use that copy multiple times
- Keep the original untouched
-
When in doubt, use MP4/MP3
- Maximum compatibility
- Works on every device
- Safe choice for sharing
-
Use lossless for archiving
- FLAC for audio
- High-bitrate WebM or MKV for video
- Future-proof your collection
Next Steps
You now understand:
- ✓ What file formats are (containers vs. codecs)
- ✓ The difference between MP3 and MP4
- ✓ Why SeaMeet uses WebM
- ✓ Which formats to use for different purposes
- ✓ How to convert between formats
Continue learning:
👉 Chapter 6: Flashback Recording Discover SeaMeet's most unique feature—the ability to record moments from the past!
Or explore:
- Chapter 10: Importing files (bring other formats into SeaMeet)
- Chapter 15: Storage management
- Chapter 22: Best practices for different scenarios
Quick Reference: Format Cheat Sheet
┌─────────────────────────────────────────────────────────────┐
│ FORMAT QUICK GUIDE │
├─────────────────────────────────────────────────────────────┤
│ │
│ AUDIO ONLY: │
│ • MP3 (universal, good compression) │
│ • M4A/AAC (Apple, better than MP3) │
│ • FLAC (perfect quality, medium size) │
│ • WAV (perfect quality, huge size) │
│ • Opus (best for voice, very efficient) │
│ │
│ VIDEO + AUDIO: │
│ • WebM (SeaMeet default, efficient, modern) │
│ • MP4 (universal compatibility) │
│ • MKV (flexible, multiple tracks) │
│ • MOV (Apple ecosystem) │
│ │
│ CODECS (What's inside): │
│ Audio: Opus > AAC > MP3 > OGG │
│ Video: VP9 ≈ H.265 > H.264 > VP8 │
│ │
│ WHEN TO USE WHAT: │
│ • Archiving: WebM, FLAC, MKV │
│ • Sharing: MP4, MP3 │
│ • Editing: WAV, high-bitrate MP4 │
│ • Voice recordings: WebM (Opus), M4A (AAC) │
│ │
└─────────────────────────────────────────────────────────────┘
Last updated: 2026-02-01
Part of the SeaMeet User Manual
Previous: Chapter 4 - Video Recording Explained
Next: Chapter 6 - Flashback Recording
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