687 MPEG 1/2 Audio Layer 3 MP3 Audio MP3 is a digital audio format, formally known as MPEG-1 Audio Layer III or MPEG-2 Audio Layer III. A third variant, known as MPEG 2.5, which supports lower bit rates implemented by the LAME MP3 encoder among others, but is not a recognised standard. Text 1 Digital Preservation Department / The National Archives 11 Mar 2005 20 Jan 2020 audio/mpeg MIME fmt/134 PUID public.mp3 Apple Uniform Type Identifier mp3 File extension 266 MPEG-1 Audio Layer 3 with ID3v2 Tag Regularly-spaced frame headers should always be discoverable near EOF. An ID3v1 tag of up to 355 bytes may be present at EOF. 1 Absolute from EOF 0 Little-endian FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{47-1795} 1 Absolute from BOF 0 Little-endian 494433 267 MPEG-2 Audio Layer 3 with ID3v2 Tag Regularly-spaced frame headers should always be discoverable near EOF. An ID3v1 tag of up to 355 bytes may be present at EOF. 1 Absolute from EOF 0 Little-endian FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{47-1795} 1 Absolute from BOF 0 Little-endian 494433 268 MPEG-1 Audio Layer 3 with ID3v2 Tag (protected) Regularly-spaced frame headers should always be discoverable near EOF. Header has CRC bit off to indicate protected. An ID3v1 tag of up to 355 bytes may be present at EOF. 1 Absolute from EOF 0 Little-endian FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{47-1795} 1 Absolute from BOF 0 Little-endian 494433 269 MPEG-2 Audio Layer 3 with ID3v2 Tag (protected) Regularly-spaced frame headers should always be discoverable near EOF. Header has CRC bit off to indicate protected. An ID3v1 tag of up to 355 bytes may be present at EOF. 1 Absolute from EOF 0 Little-endian FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{47-1795} 1 Absolute from BOF 0 Little-endian 494433 279 MPEG-1 Audio Layer 3 without ID3v2 Tag Regularly-spaced frame headers should always be discoverable starting at BOF. 1 Absolute from BOF 0 1795 Little-endian FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB]{46-1439}FFFB[10:EB] 280 MPEG-2 Audio Layer 3 without ID3v2 Tag Regularly-spaced frame headers should always be discoverable starting at BOF. 1 Absolute from BOF 0 1795 Little-endian FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB]{46-1439}FFF3[10:EB] 281 MPEG-1 Audio Layer 3 without ID3v2 Tag (protected) Regularly-spaced frame headers should always be discoverable starting at BOF with each header having CRC bit set off to indicate file is protected. 1 Absolute from BOF 0 1795 Little-endian FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB]{46-1439}FFFA[10:EB] 282 MPEG-2 Audio Layer 3 without ID3v2 Tag (protected) Regularly-spaced frame headers should always be discoverable starting at BOF with each header having CRC bit set off to indicate file is protected. 1 Absolute from BOF 0 1795 Little-endian FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB]{46-1439}FFF2[10:EB] 1733 MP3 2.5 Regularly-spaced frame headers should always be discoverable starting at BOF. MPEG 2.5 is an extended variant of MP3 that provides wider support of lower bit-rates than standard MP3. It is implemented by LAME encoder among others, however is not an officially recognised standard. 1 Absolute from BOF 0 1795 FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB]{46-1439}FFE3[10:EB] Has lower priority than 613 Acrobat PDF 1.0 - Portable Document Format Has lower priority than 614 Acrobat PDF 1.1 - Portable Document Format Has lower priority than 615 Acrobat PDF 1.2 - Portable Document Format Has lower priority than 616 Acrobat PDF 1.3 - Portable Document Format Has lower priority than 617 Acrobat PDF 1.4 - Portable Document Format Has lower priority than 618 Acrobat PDF 1.5 - Portable Document Format Has lower priority than 625 PCX Has lower priority than 637 Acrobat PDF 1.6 - Portable Document Format Has lower priority than 646 Macromedia Flash Has lower priority than 647 Macromedia Flash Has lower priority than 648 Macromedia Flash Has lower priority than 649 Macromedia Flash Has lower priority than 650 Macromedia Flash Has lower priority than 651 Macromedia Flash Has lower priority than 652 Macromedia Flash Has lower priority than 653 Macromedia FLV Has lower priority than 872 AutoCAD Drawing Has lower priority than 1016 Acrobat PDF 1.7 - Portable Document Format Has lower priority than 1099 Tagged Image File Format Has lower priority than 1192 Audio Interchange File Format Has lower priority than 1357 Matroska Has lower priority than 1986 Nullsoft Streaming Video Has lower priority than 2098 NCH Dictation Audio File Has lower priority than 2290 STOS Memory Bank Has lower priority than 2291 multiArtist File Has lower priority than 2292 MAKIchan Graphics File Has lower priority than 2384 Beam Software SIFF File Has lower priority than 2400 Spectrum 512 Compressed | Spectrum 512 Smooshed Has lower priority than 2401 Spectrum 512 Uncompressed | Spectrum 512 Uncompressed Enhanced Has lower priority than 2486 XL-Paint Has lower priority than 2539 Persuasion Mac Document Has lower priority than 2557 Pablo Paint Raster Image Has lower priority than 2597 Canon SIF File Has lower priority than 2663 Audio Data Transport Stream Has lower priority than 2686 GoDot 4Bit Graphics Format Has lower priority than 2719 SWiSH Movie File Has lower priority than 2731 GST Art File Has lower priority than 2762 VBM (VDC BitMap) File