Convert MP2 to AMR

Drag and drop files here or click to select.
Max file size 100mb.

Uploading progress:

MP2 vs AMR Format Comparison

Aspect	MP2 (Source Format)	AMR (Target Format)
Format Overview	MP2 MPEG-1 Audio Layer II MPEG-1 Audio Layer II, standardized in 1993 as part of MPEG-1, was the dominant digital audio format before MP3. MP2 uses sub-band coding with psychoacoustic analysis and remains the mandated audio codec for European DAB radio broadcasting and DVD-Video authoring. Lossy Legacy	AMR Adaptive Multi-Rate A narrow-band speech codec standardized by 3GPP in 1999, designed primarily for mobile voice communication. AMR operates at 8 kHz sampling rate with variable bitrates from 4.75 to 12.2 kbps, dynamically adapting to network conditions. Widely used by Android and Nokia phones for voice memos and call recordings, AMR delivers intelligible speech in extremely small file sizes. Lossy Legacy
Technical Specifications	Sample Rates: 16 kHz - 48 kHz Bit Rates: 32-384 kbps Channels: Mono, Stereo, Joint Stereo Codec: MPEG-1/2 Layer II Container: Raw MP2 frames (.mp2), MPEG-TS	Sample Rate: 8 kHz (narrow-band) Bit Rates: 4.75-12.2 kbps (8 modes) Channels: Mono only Codec: AMR-NB (ACELP) Container: 3GPP (.amr, .3gp)
Audio Encoding	MP2 applies sub-band filtering and psychoacoustic bit allocation to achieve lossy compression at broadcast-suitable quality: # Encode to MP2 at 384 kbps ffmpeg -i input.wav -codec:a mp2 \ -b:a 384k output.mp2 # Broadcast-standard MP2 (256 kbps, 48 kHz) ffmpeg -i input.wav -codec:a mp2 \ -b:a 256k -ar 48000 output.mp2	AMR uses Algebraic Code-Excited Linear Prediction (ACELP) to model speech signals, encoding 20 ms frames at variable bitrates: # Encode audio to AMR at default bitrate ffmpeg -i input.wav -ar 8000 -ac 1 \ -codec:a libopencore_amrnb output.amr # Specify bitrate mode (12.2 kbps best) ffmpeg -i input.wav -ar 8000 -ac 1 \ -b:a 12.2k output.amr
Audio Features	Metadata: Limited - ID3 tags possible but uncommon Album Art: Not commonly supported Gapless Playback: Not typically supported Streaming: DAB radio and MPEG-TS broadcasting Surround: Stereo only (no multichannel) Error Resilience: Better than MP3 for broadcast	Metadata: Minimal - no standard tagging system Album Art: Not supported Gapless Playback: Not applicable (speech codec) Streaming: Excellent for mobile networks (low bandwidth) Surround: Not supported (mono only) Adaptive Rate: Dynamic bitrate switching per 20 ms frame
Advantages	Mandated codec for DAB radio in Europe Robust performance for broadcast applications Lower encoding/decoding latency than MP3 Better error resilience in transmission Patent-free since 2017 Well-suited for higher bitrate applications	Extremely small file sizes (under 1 MB for several minutes of speech) Optimized for human voice with high intelligibility Dynamic bitrate adaptation to network conditions Native support on virtually all mobile phones Low CPU requirements for encoding and decoding 3GPP standard ensures broad telecom compatibility
Disadvantages	Inferior quality to MP3 at lower bitrates Limited device and software support No native web browser playback Minimal metadata capabilities Largely superseded by MP3 and AAC	8 kHz narrow-band - poor quality for music Mono only - no stereo or surround support Maximum 12.2 kbps bitrate severely limits fidelity Limited metadata and tagging capabilities Not suitable for any content beyond speech
Common Uses	DAB/DAB+ digital radio broadcasting DVD-Video audio tracks MPEG transport stream audio European broadcast television Legacy broadcast playout systems	Mobile phone voice memos and recordings Voicemail storage on cellular networks MMS audio attachments Telecom voice logging and archival Low-bandwidth voice transmission
Best For	Digital radio broadcasting (DAB) DVD authoring audio tracks Broadcast systems requiring error resilience MPEG transport stream workflows	Recording voice notes on Android devices Storing large volumes of speech recordings compactly Mobile voice communication applications Embedded systems with limited storage
Version History	Introduced: 1993 (ISO/IEC 11172-3) Current Version: MPEG-1/2 Layer II Status: Mature, patent-free since 2017 Evolution: Musicam (1989) → MPEG-1 Layer II (1993) → MPEG-2 Layer II (1995)	Introduced: 1999 (3GPP TS 26.071) Current Version: AMR-NB / AMR-WB (2001) Status: Mature, widely deployed in telecom Evolution: AMR-NB (1999) → AMR-WB (2001) → AMR-WB+ (2004) → EVS (2014)
Software Support	Media Players: VLC, foobar2000, MPC-HC Broadcast: DAB multiplexers, MPEG encoders Mobile: Android (via apps), limited iOS Editors: Audacity, GoldWave, FFmpeg Authoring: DVD Studio Pro, tmpgenc	Media Players: VLC, MPC-HC, KMPlayer Mobile: Android (native), Nokia, Samsung Editors: Audacity (via FFmpeg), GoldWave Web Browsers: Limited - not natively supported Telecom: All GSM/3G/4G networks

Why Convert MP2 to AMR?

Converting MP2 to AMR compresses broadcast-quality MPEG-1 Layer II audio into ultra-compact voice encoding for mobile telephony systems.

MP2 is used primarily in broadcasting where mobile telephony compatibility is rarely needed. When broadcast content needs to reach listeners through phone systems, AMR provides the format and compression.

The conversion reduces bitrate from MP2's 192-384 kbps to AMR's 12.2 kbps maximum, achieving 20-30x file size reduction.

MP2 source material will be severely reduced by AMR encoding. Use this conversion only when telephony requirements or extreme size constraints justify the quality trade-off.

Key Benefits of Converting MP2 to AMR:

Broadcast to Mobile: Bridge broadcasting format to telephony
30x Compression: Reduce 384 kbps MP2 to 12.2 kbps AMR
Cellular Compatible: 3GPP standard for all mobile networks
Voice Extraction: Preserve dialogue from broadcast content
MMS Ready: Small enough for mobile multimedia messages
Automated Systems: Compatible with IVR and voice notification
Network Efficient: Deliverable over minimal bandwidth

Practical Examples

Example 1: Radio News to Phone Alert System

Scenario: A news service extracts radio bulletins from DAB broadcasts in MP2 and converts to AMR for phone-based news alerts.

Source: news_bulletin_morning.mp2 (5 min, 256 kbps, 9.4 MB)
Conversion: MP2 to AMR (12.2 kbps, 8 kHz, mono)
Result: news_bulletin_morning.amr (450 KB)

Phone alert deployment:
1. Capture DAB radio bulletin as MP2
2. Convert to AMR for phone delivery
3. Distribute via automated calling system
4. Subscribers hear news via phone
5. 21:1 compression enables mass delivery

Example 2: DVD Audio to Voicemail Greeting

Scenario: A business extracts audio from a DVD promotional video (MP2 track) and converts to AMR for corporate voicemail greeting.

Source: promo_video_audio.mp2 (30 sec, 192 kbps, 720 KB)
Conversion: MP2 to AMR (12.2 kbps, 8 kHz, mono)
Result: promo_video_audio.amr (45 KB)

Voicemail setup:
- Upload to voicemail system as greeting
- Voice message clearly preserved
- Under 50 KB file size
- Compatible with all PBX systems
- Voice-only content converts well

Example 3: Transport Stream Audio Extraction

Scenario: A cable operator extracts MP2 audio from MPEG transport streams and converts to AMR for phone-based program information.

Source: channel_schedule_audio.mp2 (3 min, 128 kbps, 2.8 MB)
Conversion: MP2 to AMR (12.2 kbps, 8 kHz, mono)
Result: channel_schedule_audio.amr (270 KB)

Dial-in service:
- Convert program info for phone access
- Callers hear schedule via AMR playback
- Minimal telephony server storage
- Update frequently with small files
- Accessible from any phone

Frequently Asked Questions (FAQ)

Q: Why convert broadcast MP2 to telephony AMR?

A: When broadcast content needs to reach audiences through phone delivery (automated calls, voicemail, MMS), AMR is the standard telephony format.

Q: How much quality is lost?

A: Significant. MP2 at 192 kbps covers up to 22 kHz; AMR covers only 4 kHz. Speech remains intelligible but music and effects are degraded.

Q: Can I convert stereo MP2?

A: Yes, stereo MP2 is downmixed to mono during AMR conversion.

Q: Is there a better format than AMR for mobile delivery?

A: For modern smartphones, Opus or AAC offer far better quality. AMR is only necessary for legacy telephony systems.

Q: What happens to broadcast metadata?

A: MP2 has minimal metadata, and AMR has no metadata support. Information is not carried over.

Q: Can I use the AMR in DAB broadcasts?

A: No. DAB requires MP2 format. This conversion goes from broadcast to telephony, not the reverse.

Q: Is the conversion fast?

A: Yes. Both MP2 decoding and AMR encoding are lightweight. A 60-minute recording converts in seconds.

Q: Can I convert MP2 from transport streams directly?

A: Our converter accepts standalone MP2 files. First demux audio from MPEG-TS using FFmpeg, then convert.