{"id":"image-heif-sequence","mimeType":"image/heif-sequence","name":"High Efficiency Image File Format Sequence","shortName":"HEIF-Sequence","category":"Photography","extensions":[".heifs",".heif",".hif"],"description":"An image/heif-sequence is a container format that stores a collection of images (an image sequence) within a High Efficiency Image File Format (HEIF) structure. Unlike HEIC sequences which are strictly bound to the HEVC codec, HEIF sequences are codec-agnostic and can encapsulate image bursts or animations encoded with various compression algorithms.","seo":{"title":"image/heif-sequence MIME Type | Complete Developer Reference \u0026 Magic Bytes","description":"Complete reference for the image/heif-sequence MIME type: magic bytes, browser support matrix, HTTP headers, developer snippets, and technical specifications for HEIF sequences.","faqs":[{"question":"What is the difference between image/heif-sequence and image/heic-sequence?","answer":"Both utilize the ISOBMFF-based HEIF container for storing multiple frames. However, image/heic-sequence mandates the use of the HEVC (H.265) video codec for compression, while image/heif-sequence is a broader, codec-agnostic classification that can accommodate AVC, AV1, or JPEG encoded frames."},{"question":"What is the magic byte for a HEIF sequence?","answer":"HEIF sequences begin with a standard ISOBMFF 4-byte box size, followed by the 'ftyp' identifier, and typically use the major brand 'msf1' (Multi-picture Sequence File). The hex sequence is XX XX XX XX 66 74 79 70 6D 73 66 31 (....ftypmsf1)."},{"question":"Do web browsers support image/heif-sequence?","answer":"No. Modern web browsers do not natively support HEIF sequence files. To display animated or burst content on the web, developers should convert HEIF sequences to standardized formats like MP4, Animated WebP, or Animated AVIF."}]},"index":{"compression":["Lossy","Lossless"],"browserSupport":{"score":1,"label":"None"},"commonUses":["Burst Photography","Focal Stacking","Exposure Bracketing","Time-Lapse Data"]},"technical":{"magicBytes":{"hex":"XX XX XX XX 66 74 79 70 6D 73 66 31","ascii":"....ftypmsf1"},"container":"HEIF / ISOBMFF (ISO/IEC 14496-12)","compressionAlgorithm":["Codec Agnostic (HEVC, AVC, JPEG, AV1)"],"colorDepth":["8-bit","10-bit","12-bit","16-bit"],"transparency":true,"animation":true,"metadata":{"exif":true,"xmp":true,"iccProfile":true},"alphaChannel":true,"progressiveLoading":false,"hdrSupport":true},"history":{"developer":"Moving Picture Experts Group (MPEG)","released":"2015","specification":"ISO/IEC 23008-12 (MPEG-H Part 12)"},"browserSupport":{"chrome":false,"chromeVersion":"None","firefox":false,"firefoxVersion":"None","safari":false,"safariVersion":"None","edge":false,"edgeVersion":"None","internetExplorer":false},"softwareSupport":[{"name":"Apple Photos","logo":""},{"name":"Windows Photos (with HEIF Extension)","logo":""},{"name":"ImageMagick","logo":"image-magic.webp"}],"conversion":{"convertTo":["gif","webp","avif"],"convertFrom":["gif","webp"]},"developer":{"httpHeaders":[{"header":"Content-Type","value":"image/heif-sequence"}],"htmlAccept":"image/heif-sequence, .heifs, .heif","fileDetection":["Check bytes 4-7 for the 'ftyp' box identifier","Verify the major brand string at bytes 8-11 is 'msf1' (Multi-picture Sequence File)"]},"prosCons":{"pros":["Codec-agnostic container allows for extreme flexibility when storing multi-frame photographic data","Maintains the space-saving benefits of ISOBMFF shared frame data blocks","Excellent for archiving computational photography workloads like exposure brackets or focal stacks"],"cons":["Codec ambiguity means a decoder might be able to parse the container but fail to decode the underlying pixels","Zero native web browser support","Complex container structure requires specialized parsing libraries to extract individual frames"]},"specifications":{"url":"https://www.iso.org/standard/89035.html","rfc":"","mimeAliases":["image/heic-sequence"]},"developerSnippets":{"python":"import magic\nprint(magic.from_file('burst.heifs', mime=True)) # May output generic 'image/heif' based on the library's magic file","nodejs":"const FileType = require('file-type');\nconst type = await FileType.fromFile('burst.heifs');\nconsole.log(type.mime); // Typically resolves to image/heif","go":"import \"net/http\"\n\n// Custom ISOBMFF parsing is strongly recommended to read the 'msf1' brand from the ftyp box.","php":"$mime = mime_content_type('burst.heifs');\necho $mime; // Standard implementations often map this to application/octet-stream or image/heif"},"relatedFormats":["heif","heic-sequence","avif"]}