diff --git a/lib/miaf_utils.js b/lib/miaf_utils.js
new file mode 100644
index 0000000..47135a9
--- /dev/null
+++ b/lib/miaf_utils.js
@@ -0,0 +1,130 @@
+// Utils used to parse miaf-based files (avif/heic/heif)
+//
+// We look for last `ispe` box (first box is presumably a thumbnail). Images with metadata encoded
+// after image data are not supported. Image sequences sometimes can't be recognized if they don't have `ispe` box.
+//
+// ISO media file spec:
+// https://web.archive.org/web/20180219054429/http://l.web.umkc.edu/lizhu/teaching/2016sp.video-communication/ref/mp4.pdf
+//
+// ISO image file format spec:
+// https://standards.iso.org/ittf/PubliclyAvailableStandards/c066067_ISO_IEC_23008-12_2017.zip
+//
+
+'use strict';
+
+/* eslint-disable consistent-return */
+
+var readUInt32BE = require('./common').readUInt32BE;
+
+/*
+ * interface Box {
+ *   size:       uint32;   // if size == 0, box lasts until EOF
+ *   boxtype:    char[4];
+ *   largesize?: uint64;   // only if size == 1
+ *   usertype?:  char[16]; // only if boxtype == 'uuid'
+ * }
+ */
+function readBox(data, offset) {
+  if (data.length < 4 + offset) return null;
+
+  var size = readUInt32BE(data, offset);
+
+  // size includes first 4 bytes (length)
+  if (data.length < size + offset || size < 8) return null;
+
+  // if size === 1, real size is following uint64 (only for big boxes, not needed)
+  // if size === 0, real size is until the end of the file (only for big boxes, not needed)
+
+  return {
+    type: String.fromCharCode.apply(null, data.slice(offset + 4, offset + 8)),
+    data: data.slice(offset + 8, offset + size),
+    end:  offset + size
+  };
+}
+
+
+module.exports.readBox = readBox;
+
+
+module.exports.readSizeFromMeta = function (data) {
+  var newData, box, offset;
+
+  for (offset = 4 /* version+flags */, newData = null; (box = readBox(data, offset)); offset = box.end) {
+    if (box.type === 'iprp') {
+      newData = box.data;
+      break;
+    }
+  }
+
+  if (!newData) return;
+  data = newData;
+
+  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
+    if (box.type === 'ipco') {
+      newData = box.data;
+      break;
+    }
+  }
+
+  if (!newData) return;
+  data = newData;
+
+  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
+    if (box.type === 'ispe') {
+      newData = box.data;
+      // no break here (!), second ispe may override the first, see
+      // https://github.com/tigranbs/test-heic-images
+    }
+  }
+
+  if (!newData) return;
+  data = newData;
+
+  return {
+    width:  readUInt32BE(data, 4),
+    height: readUInt32BE(data, 8)
+  };
+};
+
+
+module.exports.getMimeType = function (data) {
+  var str = String.fromCharCode.apply(null, data);
+
+  var brand = str.slice(0, 4);
+  var compat = {};
+
+  compat[brand] = true;
+  (str.slice(8).match(/..../g) || []).forEach(function (b) {
+    compat[b] = true;
+  });
+
+  // heic and avif are superset of miaf, so they should all list mif1 as compatible
+  if (!compat.mif1 && !compat.msf1 && !compat.miaf) return;
+
+  if (brand === 'avif' || brand === 'avis' || brand === 'avio') {
+    // `.avifs` and `image/avif-sequence` are removed from spec, all files have single type
+    return { type: 'avif', mime: 'image/avif' };
+  }
+
+  // https://nokiatech.github.io/heif/technical.html
+  if (brand === 'heic' || brand === 'heix') {
+    return { type: 'heic', mime: 'image/heic' };
+  }
+
+  if (brand === 'hevc' || brand === 'hevx') {
+    return { type: 'heic', mime: 'image/heic-sequence' };
+  }
+
+  if (compat.avif || compat.avis) {
+    return { type: 'avif', mime: 'image/avif' };
+  }
+
+  if (compat.heic || compat.heix || compat.hevc || compat.hevx || compat.heis) {
+    if (compat.msf1) {
+      return { type: 'heif', mime: 'image/heif-sequence' };
+    }
+    return { type: 'heif', mime: 'image/heif' };
+  }
+
+  return { type: 'avif', mime: 'image/avif' };
+};
diff --git a/lib/parse_stream/avif.js b/lib/parse_stream/avif.js
index 16f86a7..930ed3d 100644
--- a/lib/parse_stream/avif.js
+++ b/lib/parse_stream/avif.js
@@ -1,3 +1,4 @@
+
 'use strict';
 
 /* eslint-disable consistent-return */
@@ -7,6 +8,7 @@ var ParserStream = require('../common').ParserStream;
 var str2arr      = require('../common').str2arr;
 var sliceEq      = require('../common').sliceEq;
 var readUInt32BE = require('../common').readUInt32BE;
+var miaf         = require('../miaf_utils');
 
 var SIG_FTYP = str2arr('ftyp');
 
@@ -21,92 +23,32 @@ function safeSkip(parser, count, callback) {
 }
 
 
-function readBox(data, offset) {
-  if (data.length < 4 + offset) return null;
-
-  var size = readUInt32BE(data, offset);
-
-  // size includes first 4 bytes (length)
-  if (data.length < size + offset || size < 8) return null;
-
-  // if size === 1, real size is following uint64 (only for big boxes, not needed)
-  // if size === 0, real size is until the end of the file (only for big boxes, not needed)
-
-  return {
-    type: String.fromCharCode.apply(null, data.slice(offset + 4, offset + 8)),
-    data: data.slice(offset + 8, offset + size),
-    end:  offset + size
-  };
-}
-
-
-function readAvifSizeFromMeta(data) {
-  var newData, box, offset;
-
-  for (offset = 4 /* version+flags */, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'iprp') {
-      newData = box.data;
-      break;
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'ipco') {
-      newData = box.data;
-      break;
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'ispe') {
-      newData = box.data;
-      // no break here (!), second ispe may override the first, see
-      // https://github.com/tigranbs/test-heic-images
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  return {
-    width:  readUInt32BE(data, 4),
-    height: readUInt32BE(data, 8)
-  };
-}
-
-
-function readAvifSize(parser, imgType) {
+function readAvifSize(parser, fileType) {
   parser._bytes(8, function (data) {
     var size = readUInt32BE(data, 0) - 8;
     var type = String.fromCharCode.apply(null, data.slice(4, 8));
 
-    if (size < 0) {
+    if (type === 'mdat') {
       parser._skipBytes(Infinity);
       parser.push(null);
       return;
-    } else if (type === 'mdat') {
+    } else if (size < 0) {
       parser._skipBytes(Infinity);
       parser.push(null);
       return;
-    } else if (type === 'meta') {
+    } else if (type === 'meta' && size > 0) {
       parser._bytes(size, function (data) {
         parser._skipBytes(Infinity);
 
-        var imgSize = readAvifSizeFromMeta(data);
+        var imgSize = miaf.readSizeFromMeta(data);
 
         if (!imgSize) return;
 
         parser.push({
           width:  imgSize.width,
           height: imgSize.height,
-          type:   imgType === 'heic' ? 'heic' : 'avif',
-          mime:   imgType === 'heic' ? 'image/heic' : 'image/avif',
+          type:   fileType.type,
+          mime:   fileType.mime,
           wUnits: 'px',
           hUnits: 'px'
         });
@@ -115,7 +57,7 @@ function readAvifSize(parser, imgType) {
       });
     } else {
       safeSkip(parser, size, function () {
-        readAvifSize(parser, type);
+        readAvifSize(parser, fileType);
       });
     }
   });
@@ -125,31 +67,32 @@ function readAvifSize(parser, imgType) {
 module.exports = function () {
   var parser = new ParserStream();
 
-  parser._bytes(12, function (data) {
-    if (!sliceEq(data, 4, SIG_FTYP)) {
+  parser._bytes(8, function (data) {
+    // limit first box size to 65535 by checking first 2 bytes
+    if (!sliceEq(data, 4, SIG_FTYP) || data[0] !== 0 || data[1] !== 0) {
       parser._skipBytes(Infinity);
       parser.push(null);
       return;
     }
 
-    var type = String.fromCharCode.apply(null, data.slice(8, 12));
+    var size = readUInt32BE(data, 0) - 8;
 
-    if (type !== 'heic' && type !== 'avif') {
+    if (size <= 0) {
       parser._skipBytes(Infinity);
       parser.push(null);
       return;
     }
 
-    var size = readUInt32BE(data, 0) - 12;
+    parser._bytes(size, function (data) {
+      var fileType = miaf.getMimeType(data);
 
-    if (size < 0) {
-      parser._skipBytes(Infinity);
-      parser.push(null);
-      return;
-    }
+      if (!fileType) {
+        parser._skipBytes(Infinity);
+        parser.push(null);
+        return;
+      }
 
-    safeSkip(parser, size, function () {
-      readAvifSize(parser, type);
+      readAvifSize(parser, fileType);
     });
   });
 
diff --git a/lib/parse_sync/avif.js b/lib/parse_sync/avif.js
index 6589d73..ab17477 100644
--- a/lib/parse_sync/avif.js
+++ b/lib/parse_sync/avif.js
@@ -1,9 +1,3 @@
-// ISO media file spec:
-// https://web.archive.org/web/20180219054429/http://l.web.umkc.edu/lizhu/teaching/2016sp.video-communication/ref/mp4.pdf
-//
-// ISO image file format spec:
-// https://standards.iso.org/ittf/PubliclyAvailableStandards/c066067_ISO_IEC_23008-12_2017.zip
-//
 
 /* eslint-disable consistent-return */
 
@@ -12,93 +6,29 @@
 
 var str2arr      = require('../common').str2arr;
 var sliceEq      = require('../common').sliceEq;
-var readUInt32BE = require('../common').readUInt32BE;
+var miaf         = require('../miaf_utils');
 
 var SIG_FTYP = str2arr('ftyp');
 
 
-/*
- * interface Box {
- *   size:       uint32;   // if size == 0, box lasts until EOF
- *   boxtype:    char[4];
- *   largesize?: uint64;   // only if size == 1
- *   usertype?:  char[16]; // only if boxtype == 'uuid'
- * }
- */
-function readBox(data, offset) {
-  if (data.length < 4 + offset) return null;
-
-  var size = readUInt32BE(data, offset);
-
-  // size includes first 4 bytes (length)
-  if (data.length < size + offset || size < 8) return null;
-
-  // if size === 1, real size is following uint64 (only for big boxes, not needed)
-  // if size === 0, real size is until the end of the file (only for big boxes, not needed)
-
-  return {
-    type: String.fromCharCode.apply(null, data.slice(offset + 4, offset + 8)),
-    data: data.slice(offset + 8, offset + size),
-    end:  offset + size
-  };
-}
-
-
-function readAvifSizeFromMeta(data) {
-  var newData, box, offset;
-
-  for (offset = 4 /* version+flags */, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'iprp') {
-      newData = box.data;
-      break;
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'ipco') {
-      newData = box.data;
-      break;
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
-    if (box.type === 'ispe') {
-      newData = box.data;
-      // no break here (!), second ispe may override the first, see
-      // https://github.com/tigranbs/test-heic-images
-    }
-  }
-
-  if (!newData) return;
-  data = newData;
-
-  return {
-    width:  readUInt32BE(data, 4),
-    height: readUInt32BE(data, 8)
-  };
-}
-
-
 module.exports = function (data) {
   // ISO media file (avif format) starts with ftyp box:
   // 0000 0020 6674 7970 6176 6966
   //  (length)  f t  y p  a v  i f
   //
-  if (!sliceEq(data, 4, SIG_FTYP)) return;
+  // also limit first box size to 65535 by checking first 2 bytes
+  //
+  if (!sliceEq(data, 4, SIG_FTYP) || data[0] !== 0 || data[1] !== 0) return;
 
-  var type = String.fromCharCode.apply(null, data.slice(8, 12));
+  var firstBox = miaf.readBox(data, 0);
+  if (!firstBox) return;
 
-  if (type !== 'avif' && type !== 'heic') return;
+  var fileType = miaf.getMimeType(firstBox.data);
+  if (!fileType) return;
 
   var newData, box, offset;
 
-  for (offset = 0, newData = null; (box = readBox(data, offset)); offset = box.end) {
+  for (offset = firstBox.end, newData = null; (box = miaf.readBox(data, offset)); offset = box.end) {
     // mdat block SHOULD be last (but not strictly required),
     // so it's unlikely that metadata is after it
     if (box.type === 'mdat') return;
@@ -111,15 +41,15 @@ module.exports = function (data) {
   if (!newData) return;
   data = newData;
 
-  var imgSize = readAvifSizeFromMeta(data);
+  var imgSize = miaf.readSizeFromMeta(data);
 
   if (!imgSize) return;
 
   return {
     width:  imgSize.width,
     height: imgSize.height,
-    type:   type === 'heic' ? 'heic' : 'avif',
-    mime:   type === 'heic' ? 'image/heic' : 'image/avif',
+    type:   fileType.type,
+    mime:   fileType.mime,
     wUnits: 'px',
     hUnits: 'px'
   };
diff --git a/test/fixtures/MIAF002.heic b/test/fixtures/MIAF002.heic
new file mode 100644
index 0000000..71e4ebe
Binary files /dev/null and b/test/fixtures/MIAF002.heic differ
diff --git a/test/fixtures/README.md b/test/fixtures/README.md
index 1e699d5..9ca09b9 100644
--- a/test/fixtures/README.md
+++ b/test/fixtures/README.md
@@ -1 +1,5 @@
 Fixtures derived from https://github.com/nodejs/node/issues/37, author: @substack, license: public domain/CC0.
+
+`image4.heic` is from [tigranbs/test-heic-images](https://github.com/tigranbs/test-heic-images).
+
+`MIAF002.heic` is from [nokiatech/heif_conformance](https://github.com/nokiatech/heif_conformance).
diff --git a/test/fixtures/image4.heic b/test/fixtures/image4.heic
new file mode 100644
index 0000000..efd119a
Binary files /dev/null and b/test/fixtures/image4.heic differ
diff --git a/test/test_formats.js b/test/test_formats.js
index 13c0a46..081d3fc 100644
--- a/test/test_formats.js
+++ b/test/test_formats.js
@@ -313,24 +313,25 @@ describe('File formats', function () {
     });
 
 
-    it('minimal AVIF file', async function () {
-      let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
-        '\0\0\0\x30 meta \0\0\0\0 ' +
-        '\0\0\0\x24 iprp ' +
-        '\0\0\0\x1C ipco ' +
-        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
-      ).replace(/ /g, ''));
+    it('should detect HEIC - image4.heic', async function () {
+      let file = path.join(__dirname, 'fixtures', 'image4.heic');
+      let size = await probe(fs.createReadStream(file));
 
-      let size = await probe(Readable.from([ Buffer.from(buf) ]));
+      assert.deepStrictEqual(size, { width: 700, height: 476, type: 'heic', mime: 'image/heic', wUnits: 'px', hUnits: 'px' });
+    });
 
-      assert.deepStrictEqual(size, { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
+
+    it('should detect HEIC - MIAF002.heic', async function () {
+      let file = path.join(__dirname, 'fixtures', 'MIAF002.heic');
+      let size = await probe(fs.createReadStream(file));
+
+      assert.deepStrictEqual(size, { width: 160, height: 160, type: 'heif', mime: 'image/heif', wUnits: 'px', hUnits: 'px' });
     });
 
 
-    it('minimal HEIC file', async function () {
+    it('minimal AVIF file', async function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp heic ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -339,14 +340,14 @@ describe('File formats', function () {
 
       let size = await probe(Readable.from([ Buffer.from(buf) ]));
 
-      assert.deepStrictEqual(size, { width: 16909060, height: 84281096, type: 'heic', mime: 'image/heic', wUnits: 'px', hUnits: 'px' });
+      assert.deepStrictEqual(size, { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
     });
 
 
     // these images have real sizes last: https://github.com/tigranbs/test-heic-images
     it('should keep last size in ispe', async function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x44 meta \0\0\0\0 ' +
         '\0\0\0\x38 iprp ' +
         '\0\0\0\x30 ipco ' +
@@ -362,7 +363,7 @@ describe('File formats', function () {
 
     it('invalid format (mp4)', async function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp 3gp5 ' +
+        '\0\0\0\x10 ftyp 3gp5 \0\0\0\0' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -380,7 +381,7 @@ describe('File formats', function () {
       let buf;
 
       buf = str2arr((
-        '\0\0\0\x06 ftyp avif ' +
+        '\0\0\0\x06 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -393,7 +394,7 @@ describe('File formats', function () {
       );
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x06 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -406,7 +407,7 @@ describe('File formats', function () {
       );
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x06 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -419,7 +420,7 @@ describe('File formats', function () {
       );
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x06 ipco ' +
@@ -432,7 +433,7 @@ describe('File formats', function () {
       );
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -450,7 +451,7 @@ describe('File formats', function () {
       let buf;
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x0C mdat \0\0\0\0 ' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
@@ -467,7 +468,8 @@ describe('File formats', function () {
 
     it('coverage - other fields', async function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
+        '\0\0\0\x08 free ' +
         '\0\0\0\x0C free \0\0\0\0 ' +
         '\0\0\0\x4C meta \0\0\0\0 ' +
         '\0\0\0\x08 free ' +
@@ -483,6 +485,76 @@ describe('File formats', function () {
 
       assert.deepStrictEqual(size, { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
     });
+
+
+    it('coverage - mime types', async function () {
+      let buf;
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp hevc \0\0\0\0 msf1' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        (await probe(Readable.from([ Buffer.from(buf) ]))).mime,
+        'image/heic-sequence'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 avif' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        (await probe(Readable.from([ Buffer.from(buf) ]))).mime,
+        'image/avif'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp msf1 \0\0\0\0 heix' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        (await probe(Readable.from([ Buffer.from(buf) ]))).mime,
+        'image/heif-sequence'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 heix' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        (await probe(Readable.from([ Buffer.from(buf) ]))).mime,
+        'image/heif'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 xxxx' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        (await probe(Readable.from([ Buffer.from(buf) ]))).mime,
+        'image/avif'
+      );
+    });
   });
 
 
@@ -495,36 +567,39 @@ describe('File formats', function () {
     });
 
 
-    it('minimal AVIF file', function () {
-      let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
-        '\0\0\0\x30 meta \0\0\0\0 ' +
-        '\0\0\0\x24 iprp ' +
-        '\0\0\0\x1C ipco ' +
-        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
-      ).replace(/ /g, ''));
+    it('should detect HEIC - image4.heic', async function () {
+      let file = path.join(__dirname, 'fixtures', 'image4.heic');
+      let size = probe.sync(fs.readFileSync(file));
 
-      assert.deepStrictEqual(probe.sync(buf), { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
+      assert.deepStrictEqual(size, { width: 700, height: 476, type: 'heic', mime: 'image/heic', wUnits: 'px', hUnits: 'px' });
     });
 
 
-    it('minimal HEIC file', function () {
+    it('should detect HEIC - MIAF002.heic', async function () {
+      let file = path.join(__dirname, 'fixtures', 'MIAF002.heic');
+      let size = probe.sync(fs.readFileSync(file));
+
+      assert.deepStrictEqual(size, { width: 160, height: 160, type: 'heif', mime: 'image/heif', wUnits: 'px', hUnits: 'px' });
+    });
+
+
+    it('minimal AVIF file', function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp heic ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
         '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
       ).replace(/ /g, ''));
 
-      assert.deepStrictEqual(probe.sync(buf), { width: 16909060, height: 84281096, type: 'heic', mime: 'image/heic', wUnits: 'px', hUnits: 'px' });
+      assert.deepStrictEqual(probe.sync(buf), { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
     });
 
 
     // these images have real sizes last: https://github.com/tigranbs/test-heic-images
     it('should keep last size in ispe', function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x44 meta \0\0\0\0 ' +
         '\0\0\0\x38 iprp ' +
         '\0\0\0\x30 ipco ' +
@@ -538,7 +613,7 @@ describe('File formats', function () {
 
     it('invalid format (mp4)', function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp 3gp5 ' +
+        '\0\0\0\x10 ftyp 3gp5 \0\0\0\0' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -553,7 +628,7 @@ describe('File formats', function () {
       let buf;
 
       buf = str2arr((
-        '\0\0\0\x06 ftyp avif ' +
+        '\0\0\0\x06 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -563,7 +638,7 @@ describe('File formats', function () {
       assert.strictEqual(probe.sync(buf), null);
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x06 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -573,7 +648,7 @@ describe('File formats', function () {
       assert.strictEqual(probe.sync(buf), null);
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x06 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -583,7 +658,7 @@ describe('File formats', function () {
       assert.strictEqual(probe.sync(buf), null);
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x06 ipco ' +
@@ -593,7 +668,7 @@ describe('File formats', function () {
       assert.strictEqual(probe.sync(buf), null);
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
         '\0\0\0\x1C ipco ' +
@@ -608,7 +683,7 @@ describe('File formats', function () {
       let buf;
 
       buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
         '\0\0\0\x0C mdat \0\0\0\0 ' +
         '\0\0\0\x30 meta \0\0\0\0 ' +
         '\0\0\0\x24 iprp ' +
@@ -622,7 +697,8 @@ describe('File formats', function () {
 
     it('coverage - other fields', function () {
       let buf = str2arr((
-        '\0\0\0\x0C ftyp avif ' +
+        '\0\0\0\x14 ftyp avif \0\0\0\0 mif1' +
+        '\0\0\0\x08 free ' +
         '\0\0\0\x0C free \0\0\0\0 ' +
         '\0\0\0\x4C meta \0\0\0\0 ' +
         '\0\0\0\x08 free ' +
@@ -636,6 +712,76 @@ describe('File formats', function () {
 
       assert.deepStrictEqual(probe.sync(buf), { width: 16909060, height: 84281096, type: 'avif', mime: 'image/avif', wUnits: 'px', hUnits: 'px' });
     });
+
+
+    it('coverage - mime types', async function () {
+      let buf;
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp hevc \0\0\0\0 msf1' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        probe.sync(buf).mime,
+        'image/heic-sequence'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 avif' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        probe.sync(buf).mime,
+        'image/avif'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp msf1 \0\0\0\0 heix' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        probe.sync(buf).mime,
+        'image/heif-sequence'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 heix' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        probe.sync(buf).mime,
+        'image/heif'
+      );
+
+      buf = str2arr((
+        '\0\0\0\x14 ftyp mif1 \0\0\0\0 xxxx' +
+        '\0\0\0\x30 meta \0\0\0\0 ' +
+        '\0\0\0\x24 iprp ' +
+        '\0\0\0\x1C ipco ' +
+        '\0\0\0\x14 ispe \0\0\0\0 \x01\x02\x03\x04 \x05\x06\x07\x08'
+      ).replace(/ /g, ''));
+
+      assert.strictEqual(
+        probe.sync(buf).mime,
+        'image/avif'
+      );
+    });
   });