diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BMFFConstants.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BMFFConstants.kt
index 09048923..ead1bb60 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BMFFConstants.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BMFFConstants.kt
@@ -21,11 +21,14 @@ object BMFFConstants {
 
     val BMFF_BYTE_ORDER = ByteOrder.BIG_ENDIAN
 
-    /* BoxType must be always 4 bytes */
+    /** BoxType must be always 4 bytes */
     const val TPYE_LENGTH = 4
 
-    /* 4 length bytes + 4 type bytes */
-    const val BOX_HEADER_LENGTH = 8
+    /** The size is presented as unsinged integer */
+    const val SIZE_LENGTH = 4
+
+    /** 4 size bytes + 4 type bytes */
+    const val BOX_HEADER_LENGTH = TPYE_LENGTH + SIZE_LENGTH
 
     const val TIFF_HEADER_OFFSET_BYTE_COUNT = 4
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BaseMediaFileFormatImageParser.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BaseMediaFileFormatImageParser.kt
index 1cbe9172..11ef8296 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BaseMediaFileFormatImageParser.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BaseMediaFileFormatImageParser.kt
@@ -24,11 +24,10 @@ import com.ashampoo.kim.format.bmff.BMFFConstants.BMFF_BYTE_ORDER
 import com.ashampoo.kim.format.bmff.BMFFConstants.TIFF_HEADER_OFFSET_BYTE_COUNT
 import com.ashampoo.kim.format.bmff.box.FileTypeBox
 import com.ashampoo.kim.format.bmff.box.MetaBox
+import com.ashampoo.kim.format.jxl.JxlReader
 import com.ashampoo.kim.format.tiff.TiffReader
 import com.ashampoo.kim.input.ByteArrayByteReader
 import com.ashampoo.kim.input.ByteReader
-import com.ashampoo.kim.input.PositionTrackingByteReader
-import com.ashampoo.kim.input.PositionTrackingByteReaderDecorator
 
 /**
  * Reads containers that follow the ISO base media file format
@@ -39,17 +38,18 @@ import com.ashampoo.kim.input.PositionTrackingByteReaderDecorator
  */
 object BaseMediaFileFormatImageParser : ImageParser {
 
-    override fun parseMetadata(byteReader: ByteReader): ImageMetadata =
-        parseMetadata(PositionTrackingByteReaderDecorator(byteReader))
-
-    private fun parseMetadata(byteReader: PositionTrackingByteReader): ImageMetadata {
+    override fun parseMetadata(byteReader: ByteReader): ImageMetadata {
 
         val copyByteReader = CopyByteReader(byteReader)
 
+        var position: Long = 0
+
         val allBoxes = BoxReader.readBoxes(
             byteReader = copyByteReader,
             stopAfterMetadataRead = true,
-            offsetShift = 0
+            positionOffset = 0,
+            offsetShift = 0,
+            updatePosition = { position = it }
         )
 
         if (allBoxes.isEmpty())
@@ -66,7 +66,7 @@ object BaseMediaFileFormatImageParser : ImageParser {
          * This format has EXIF & XMP neatly in dedicated boxes, so we can just extract these.
          */
         if (fileTypeBox.majorBrand == FileTypeBox.JXL_BRAND)
-            return JxlHandler.createMetadata(allBoxes)
+            return JxlReader.createMetadata(allBoxes)
 
         val metaBox = allBoxes.filterIsInstance<MetaBox>().firstOrNull()
 
@@ -98,11 +98,16 @@ object BaseMediaFileFormatImageParser : ImageParser {
          * in buffer and input everything we read so far in again.
          * FIXME There must be a better solution. Find it.
          */
-        val byteReaderToUse = if (byteReader.position <= minOffset)
+        val onPositionBeforeMinimumOffset = position <= minOffset
+
+        val byteReaderToUse = if (onPositionBeforeMinimumOffset)
             byteReader
         else
             ByteArrayByteReader(copyByteReader.getBytes())
 
+        if (!onPositionBeforeMinimumOffset)
+            position = 0
+
         var exifBytes: ByteArray? = null
         var xmp: String? = null
 
@@ -110,14 +115,18 @@ object BaseMediaFileFormatImageParser : ImageParser {
 
             when (offset.type) {
 
-                MetadataType.EXIF ->
-                    exifBytes = readExifBytes(byteReaderToUse, offset)
+                MetadataType.EXIF -> {
+                    exifBytes = readExifBytes(byteReaderToUse, position, offset)
+                    position = offset.offset + offset.length
+                }
 
                 MetadataType.IPTC ->
                     continue // Unsupported
 
-                MetadataType.XMP ->
-                    xmp = readXmpString(byteReaderToUse, offset)
+                MetadataType.XMP -> {
+                    xmp = readXmpString(byteReaderToUse, position, offset)
+                    position = offset.offset + offset.length
+                }
             }
         }
 
@@ -134,11 +143,16 @@ object BaseMediaFileFormatImageParser : ImageParser {
     }
 
     private fun readExifBytes(
-        byteReader: PositionTrackingByteReader,
+        byteReader: ByteReader,
+        position: Long,
         offset: MetadataOffset
     ): ByteArray {
 
-        val bytesToSkip = offset.offset - byteReader.position
+        val bytesToSkip = offset.offset - position
+
+        check(bytesToSkip >= 0) {
+            "Position must be before extent offset: position=$position offset=$offset"
+        }
 
         byteReader.skipBytes("offset to EXIF extent", bytesToSkip.toInt())
 
@@ -148,17 +162,23 @@ object BaseMediaFileFormatImageParser : ImageParser {
         /* Usualy there are 6 bytes skipped, which are the EXIF header. ("Exif.."). */
         byteReader.skipBytes("offset to TIFF header", tiffHeaderOffset)
 
-        return byteReader.readBytes(
+        val exifBytesLength =
             offset.length.toInt() - TIFF_HEADER_OFFSET_BYTE_COUNT - tiffHeaderOffset
-        )
+
+        return byteReader.readBytes(exifBytesLength)
     }
 
     private fun readXmpString(
-        byteReader: PositionTrackingByteReader,
+        byteReader: ByteReader,
+        position: Long,
         offset: MetadataOffset
     ): String {
 
-        val bytesToSkip = offset.offset - byteReader.position
+        val bytesToSkip = offset.offset - position
+
+        check(bytesToSkip >= 0) {
+            "Position must be before extent offset: position=$position offset=$offset"
+        }
 
         byteReader.skipBytes("offset to MIME extent", bytesToSkip.toInt())
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BoxReader.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BoxReader.kt
index 2f841977..c4975ca5 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BoxReader.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/BoxReader.kt
@@ -18,18 +18,18 @@ package com.ashampoo.kim.format.bmff
 
 import com.ashampoo.kim.format.bmff.BMFFConstants.BMFF_BYTE_ORDER
 import com.ashampoo.kim.format.bmff.box.Box
-import com.ashampoo.kim.format.bmff.box.ExifBox
 import com.ashampoo.kim.format.bmff.box.FileTypeBox
 import com.ashampoo.kim.format.bmff.box.HandlerReferenceBox
 import com.ashampoo.kim.format.bmff.box.ItemInfoEntryBox
 import com.ashampoo.kim.format.bmff.box.ItemInformationBox
 import com.ashampoo.kim.format.bmff.box.ItemLocationBox
-import com.ashampoo.kim.format.bmff.box.JxlParticalCodestreamBox
 import com.ashampoo.kim.format.bmff.box.MediaDataBox
 import com.ashampoo.kim.format.bmff.box.MetaBox
 import com.ashampoo.kim.format.bmff.box.PrimaryItemBox
-import com.ashampoo.kim.format.bmff.box.XmlBox
-import com.ashampoo.kim.input.PositionTrackingByteReader
+import com.ashampoo.kim.format.jxl.box.ExifBox
+import com.ashampoo.kim.format.jxl.box.JxlParticalCodestreamBox
+import com.ashampoo.kim.format.jxl.box.XmlBox
+import com.ashampoo.kim.input.ByteReader
 
 /**
  * Reads ISOBMFF boxes
@@ -43,34 +43,42 @@ object BoxReader {
      * For iPhone HEIC this is possible, but Samsung HEIC has "meta" coming after "mdat"
      */
     fun readBoxes(
-        byteReader: PositionTrackingByteReader,
+        byteReader: ByteReader,
         stopAfterMetadataRead: Boolean = false,
-        offsetShift: Long = 0
+        positionOffset: Long = 0,
+        offsetShift: Long = 0,
+        updatePosition: ((Long) -> Unit)? = null
     ): List<Box> {
 
         var haveSeenJxlHeaderBox: Boolean = false
 
         val boxes = mutableListOf<Box>()
 
+        var position: Long = positionOffset
+
         while (true) {
 
+            val available = byteReader.contentLength - position
+
             /*
              * Check if there are enough bytes for another box.
              * If so, we at least need the 8 header bytes.
              */
-            if (byteReader.available < BMFFConstants.BOX_HEADER_LENGTH)
+            if (available < BMFFConstants.BOX_HEADER_LENGTH)
                 break
 
-            val offset: Long = byteReader.position.toLong()
+            val offset: Long = position
 
             /* Note: The length includes the 8 header bytes. */
-            val length: Long =
+            val size: Long =
                 byteReader.read4BytesAsInt("length", BMFF_BYTE_ORDER).toLong()
 
             val type = BoxType.of(
                 byteReader.readBytes("type", BMFFConstants.TPYE_LENGTH)
             )
 
+            position += BMFFConstants.BOX_HEADER_LENGTH
+
             /*
              * If we read an JXL file and we already have seen the header,
              * all reamining JXLP boxes are image data that we can skip.
@@ -78,39 +86,51 @@ object BoxReader {
             if (stopAfterMetadataRead && type == BoxType.JXLP && haveSeenJxlHeaderBox)
                 break
 
-            val actualLength: Long = when (length) {
+            var largeSize: Long? = null
+
+            val actualLength: Long = when (size) {
 
                 /* A vaule of zero indicates that it's the last box. */
-                0L -> byteReader.available
+                0L -> available
 
                 /* A length of 1 indicates that we should read the next 8 bytes to get a long value. */
-                1L -> byteReader.read8BytesAsLong("length", BMFF_BYTE_ORDER)
+                1L -> {
+                    largeSize = byteReader.read8BytesAsLong("length", BMFF_BYTE_ORDER)
+                    largeSize
+                }
 
                 /* Keep the length we already read. */
-                else -> length
+                else -> size
             }
 
             val nextBoxOffset = offset + actualLength
 
-            val remainingBytesToReadInThisBox = (nextBoxOffset - byteReader.position).toInt()
+            @Suppress("MagicNumber")
+            if (size == 1L)
+                position += 8
+
+            val remainingBytesToReadInThisBox = (nextBoxOffset - position).toInt()
 
             val bytes = byteReader.readBytes("data", remainingBytesToReadInThisBox)
 
+            position += remainingBytesToReadInThisBox
+
             val globalOffset = offset + offsetShift
 
             val box = when (type) {
-                BoxType.FTYP -> FileTypeBox(globalOffset, actualLength, bytes)
-                BoxType.META -> MetaBox(globalOffset, actualLength, bytes)
-                BoxType.HDLR -> HandlerReferenceBox(globalOffset, actualLength, bytes)
-                BoxType.IINF -> ItemInformationBox(globalOffset, actualLength, bytes)
-                BoxType.INFE -> ItemInfoEntryBox(globalOffset, actualLength, bytes)
-                BoxType.ILOC -> ItemLocationBox(globalOffset, actualLength, bytes)
-                BoxType.PITM -> PrimaryItemBox(globalOffset, actualLength, bytes)
-                BoxType.MDAT -> MediaDataBox(globalOffset, actualLength, bytes)
-                BoxType.EXIF -> ExifBox(globalOffset, actualLength, bytes)
-                BoxType.XML -> XmlBox(globalOffset, actualLength, bytes)
-                BoxType.JXLP -> JxlParticalCodestreamBox(globalOffset, actualLength, bytes)
-                else -> Box(type, globalOffset, actualLength, bytes)
+                BoxType.FTYP -> FileTypeBox(globalOffset, size, largeSize, bytes)
+                BoxType.META -> MetaBox(globalOffset, size, largeSize, bytes)
+                BoxType.HDLR -> HandlerReferenceBox(globalOffset, size, largeSize, bytes)
+                BoxType.IINF -> ItemInformationBox(globalOffset, size, largeSize, bytes)
+                BoxType.INFE -> ItemInfoEntryBox(globalOffset, size, largeSize, bytes)
+                BoxType.ILOC -> ItemLocationBox(globalOffset, size, largeSize, bytes)
+                BoxType.PITM -> PrimaryItemBox(globalOffset, size, largeSize, bytes)
+                BoxType.MDAT -> MediaDataBox(globalOffset, size, largeSize, bytes)
+                /* JXL boxes */
+                BoxType.EXIF -> ExifBox(globalOffset, size, largeSize, bytes)
+                BoxType.XML -> XmlBox(globalOffset, size, largeSize, bytes)
+                BoxType.JXLP -> JxlParticalCodestreamBox(globalOffset, size, largeSize, bytes)
+                else -> Box(type, globalOffset, size, largeSize, bytes)
             }
 
             boxes.add(box)
@@ -135,6 +155,8 @@ object BoxReader {
             }
         }
 
+        updatePosition?.let { it(position) }
+
         return boxes
     }
 }
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/CopyByteReader.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/CopyByteReader.kt
index c78c9e8c..203048b3 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/CopyByteReader.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/CopyByteReader.kt
@@ -15,24 +15,18 @@
  */
 package com.ashampoo.kim.format.bmff
 
-import com.ashampoo.kim.input.PositionTrackingByteReader
+import com.ashampoo.kim.input.ByteReader
 import com.ashampoo.kim.output.ByteArrayByteWriter
 
 internal class CopyByteReader(
-    val byteReader: PositionTrackingByteReader
-) : PositionTrackingByteReader {
+    val byteReader: ByteReader
+) : ByteReader {
 
     private val byteWriter = ByteArrayByteWriter()
 
     override val contentLength: Long =
         byteReader.contentLength
 
-    override val position: Int
-        get() = byteReader.position
-
-    override val available: Long
-        get() = byteReader.available
-
     fun getBytes(): ByteArray =
         byteWriter.toByteArray()
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/Box.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/Box.kt
index 8ac859c0..3913fe5f 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/Box.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/Box.kt
@@ -16,16 +16,32 @@
  */
 package com.ashampoo.kim.format.bmff.box
 
+import com.ashampoo.kim.format.bmff.BMFFConstants.BOX_HEADER_LENGTH
 import com.ashampoo.kim.format.bmff.BoxType
 
 open class Box(
     val type: BoxType,
     val offset: Long,
-    val length: Long,
-    /* Payload bytes, not including type & length bytes */
+    val size: Long,
+    val largeSize: Long?,
+    /** Payload bytes, not including type & length bytes */
     val payload: ByteArray
 ) {
 
+    /*
+     * "size" is an integer that specifies the number of bytes in this box,
+     * including all its fields and contained boxes; if size is 1 then the
+     * actual size is in the field largesize; if size is 0, then this
+     * box is the last one in the file, and its contents extend to the
+     * end of the file (normally only used for a Media Data Box)
+     */
+    val actualLength: Long =
+        when (size) {
+            0L -> BOX_HEADER_LENGTH.toLong() + payload.size
+            1L -> largeSize!!
+            else -> size
+        }
+
     override fun toString(): String =
-        "Box '$type' @ $offset ($length bytes)"
+        "Box '$type' @ $offset ($actualLength bytes)"
 }
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/FileTypeBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/FileTypeBox.kt
index 0003e491..6735cb84 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/FileTypeBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/FileTypeBox.kt
@@ -19,6 +19,7 @@ package com.ashampoo.kim.format.bmff.box
 import com.ashampoo.kim.common.toFourCCTypeString
 import com.ashampoo.kim.format.bmff.BMFFConstants
 import com.ashampoo.kim.format.bmff.BMFFConstants.BMFF_BYTE_ORDER
+import com.ashampoo.kim.format.bmff.BMFFConstants.BOX_HEADER_LENGTH
 import com.ashampoo.kim.format.bmff.BoxType
 import com.ashampoo.kim.input.ByteArrayByteReader
 
@@ -27,9 +28,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class FileTypeBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.FTYP, offset, length, payload) {
+) : Box(BoxType.FTYP, offset, size, largeSize, payload) {
 
     val majorBrand: String
 
@@ -49,7 +51,7 @@ class FileTypeBox(
             .read4BytesAsInt("minorBrand", BMFF_BYTE_ORDER)
             .toFourCCTypeString()
 
-        val brandCount: Int = (length.toInt() - 8 - 8) / 4
+        val brandCount: Int = (actualLength.toInt() - BOX_HEADER_LENGTH - 8 - 8) / 4
 
         val brands = mutableListOf<String>()
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/HandlerReferenceBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/HandlerReferenceBox.kt
index 78428c91..e55cb135 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/HandlerReferenceBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/HandlerReferenceBox.kt
@@ -25,9 +25,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class HandlerReferenceBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.HDLR, offset, length, payload) {
+) : Box(BoxType.HDLR, offset, size, largeSize, payload) {
 
     val version: Int
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInfoEntryBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInfoEntryBox.kt
index 7bb20743..aae3fbc1 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInfoEntryBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInfoEntryBox.kt
@@ -27,9 +27,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class ItemInfoEntryBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.INFE, offset, length, payload) {
+) : Box(BoxType.INFE, offset, size, largeSize, payload) {
 
     val version: Int
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInformationBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInformationBox.kt
index 1dd7ca1d..2fcd7453 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInformationBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemInformationBox.kt
@@ -27,9 +27,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class ItemInformationBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.IINF, offset, length, payload), BoxContainer {
+) : Box(BoxType.IINF, offset, size, largeSize, payload), BoxContainer {
 
     val version: Int
 
@@ -57,7 +58,8 @@ class ItemInformationBox(
         boxes = BoxReader.readBoxes(
             byteReader = byteReader,
             stopAfterMetadataRead = false,
-            offsetShift = offset + 4 + 2 + if (version == 0) 2 else 4
+            positionOffset = 4L + if (version == 0) 2 else 4,
+            offsetShift = offset + 4 + if (version == 0) 2 else 4
         )
 
         val map = mutableMapOf<Int, ItemInfoEntryBox>()
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemLocationBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemLocationBox.kt
index 0825ceaf..3254bd96 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemLocationBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ItemLocationBox.kt
@@ -26,9 +26,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class ItemLocationBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.ILOC, offset, length, payload) {
+) : Box(BoxType.ILOC, offset, size, largeSize, payload) {
 
     /**
      * The version of the box.
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MediaDataBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MediaDataBox.kt
index 99fa98aa..72cb167c 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MediaDataBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MediaDataBox.kt
@@ -26,9 +26,10 @@ import com.ashampoo.kim.format.bmff.BoxType
  */
 class MediaDataBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.MDAT, offset, length, payload) {
+) : Box(BoxType.MDAT, offset, size, largeSize, payload) {
 
     override fun toString(): String =
         "$type Box"
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MetaBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MetaBox.kt
index 4cc52c42..24e01df1 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MetaBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/MetaBox.kt
@@ -31,9 +31,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class MetaBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.META, offset, length, payload), BoxContainer {
+) : Box(BoxType.META, offset, size, largeSize, payload), BoxContainer {
 
     val version: Int
 
@@ -58,6 +59,7 @@ class MetaBox(
         boxes = BoxReader.readBoxes(
             byteReader = byteReader,
             stopAfterMetadataRead = false,
+            positionOffset = 4,
             offsetShift = offset + 8
         )
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/PrimaryItemBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/PrimaryItemBox.kt
index 75a56966..cdc93c0a 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/PrimaryItemBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/PrimaryItemBox.kt
@@ -26,9 +26,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class PrimaryItemBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.PITM, offset, length, payload) {
+) : Box(BoxType.PITM, offset, size, largeSize, payload) {
 
     val version: Int
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/JxlHandler.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/JxlReader.kt
similarity index 64%
rename from src/commonMain/kotlin/com/ashampoo/kim/format/bmff/JxlHandler.kt
rename to src/commonMain/kotlin/com/ashampoo/kim/format/jxl/JxlReader.kt
index 921888c9..42e9be5a 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/JxlHandler.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/JxlReader.kt
@@ -5,23 +5,23 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
  */
-package com.ashampoo.kim.format.bmff
+package com.ashampoo.kim.format.jxl
 
 import com.ashampoo.kim.format.ImageMetadata
 import com.ashampoo.kim.format.bmff.box.Box
-import com.ashampoo.kim.format.bmff.box.ExifBox
-import com.ashampoo.kim.format.bmff.box.XmlBox
+import com.ashampoo.kim.format.jxl.box.ExifBox
+import com.ashampoo.kim.format.jxl.box.XmlBox
 import com.ashampoo.kim.model.ImageFormat
 
-internal object JxlHandler {
+internal object JxlReader {
 
     fun createMetadata(allBoxes: List<Box>): ImageMetadata {
 
@@ -29,8 +29,8 @@ internal object JxlHandler {
         val xmlBox = allBoxes.filterIsInstance<XmlBox>().firstOrNull()
 
         return ImageMetadata(
-            imageFormat = ImageFormat.JXL, // could be any ISO BMFF
-            imageSize = null, // not covered by ISO BMFF
+            imageFormat = ImageFormat.JXL,
+            imageSize = null, // TODO https://github.com/Ashampoo/kim/issues/65
             exif = exifBox?.tiffContents,
             exifBytes = exifBox?.exifBytes,
             iptc = null, // not covered by ISO BMFF
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ExifBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/ExifBox.kt
similarity index 72%
rename from src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ExifBox.kt
rename to src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/ExifBox.kt
index fedc97f8..adf2b64f 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/ExifBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/ExifBox.kt
@@ -5,17 +5,18 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
  */
-package com.ashampoo.kim.format.bmff.box
+package com.ashampoo.kim.format.jxl.box
 
 import com.ashampoo.kim.format.bmff.BoxType
+import com.ashampoo.kim.format.bmff.box.Box
 import com.ashampoo.kim.format.tiff.TiffContents
 import com.ashampoo.kim.format.tiff.TiffReader
 import com.ashampoo.kim.input.ByteArrayByteReader
@@ -25,9 +26,10 @@ import com.ashampoo.kim.input.ByteArrayByteReader
  */
 class ExifBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.EXIF, offset, length, payload) {
+) : Box(BoxType.EXIF, offset, size, largeSize, payload) {
 
     val version: Int
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/JxlParticalCodestreamBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/JxlParticalCodestreamBox.kt
similarity index 67%
rename from src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/JxlParticalCodestreamBox.kt
rename to src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/JxlParticalCodestreamBox.kt
index 4b3d2e90..e03cc4d5 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/JxlParticalCodestreamBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/JxlParticalCodestreamBox.kt
@@ -5,26 +5,28 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
  */
-package com.ashampoo.kim.format.bmff.box
+package com.ashampoo.kim.format.jxl.box
 
 import com.ashampoo.kim.format.bmff.BoxType
+import com.ashampoo.kim.format.bmff.box.Box
 
 /**
  * JPEG XL jxlp box
  */
 class JxlParticalCodestreamBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.JXLP, offset, length, payload) {
+) : Box(BoxType.JXLP, offset, size, largeSize, payload) {
 
     val isHeader: Boolean
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/XmlBox.kt b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/XmlBox.kt
similarity index 58%
rename from src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/XmlBox.kt
rename to src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/XmlBox.kt
index d05aff58..27597b62 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/format/bmff/box/XmlBox.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/format/jxl/box/XmlBox.kt
@@ -5,26 +5,28 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
  */
-package com.ashampoo.kim.format.bmff.box
+package com.ashampoo.kim.format.jxl.box
 
 import com.ashampoo.kim.format.bmff.BoxType
+import com.ashampoo.kim.format.bmff.box.Box
 
 /**
  * JPEG XL XML box
  */
 class XmlBox(
     offset: Long,
-    length: Long,
+    size: Long,
+    largeSize: Long?,
     payload: ByteArray
-) : Box(BoxType.XML, offset, length, payload) {
+) : Box(BoxType.XML, offset, size, largeSize, payload) {
 
     val xmp: String
 
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/input/ByteArrayByteReader.kt b/src/commonMain/kotlin/com/ashampoo/kim/input/ByteArrayByteReader.kt
index 4bff7e15..91b40e7f 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/input/ByteArrayByteReader.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/input/ByteArrayByteReader.kt
@@ -27,17 +27,11 @@ import kotlin.math.min
  */
 class ByteArrayByteReader(
     private val bytes: ByteArray
-) : RandomAccessByteReader, PositionTrackingByteReader {
+) : RandomAccessByteReader {
 
     override val contentLength: Long =
         bytes.size.toLong()
 
-    override val position: Int
-        get() = currentPosition
-
-    override val available: Long
-        get() = contentLength - position
-
     private var currentPosition = 0
 
     override fun readByte(): Byte? {
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/input/DefaultRandomAccessByteReader.kt b/src/commonMain/kotlin/com/ashampoo/kim/input/DefaultRandomAccessByteReader.kt
index 204d9fbf..ba98e34b 100644
--- a/src/commonMain/kotlin/com/ashampoo/kim/input/DefaultRandomAccessByteReader.kt
+++ b/src/commonMain/kotlin/com/ashampoo/kim/input/DefaultRandomAccessByteReader.kt
@@ -21,17 +21,11 @@ package com.ashampoo.kim.input
  */
 class DefaultRandomAccessByteReader(
     val byteReader: ByteReader
-) : RandomAccessByteReader, PositionTrackingByteReader {
+) : RandomAccessByteReader {
 
     override val contentLength: Long =
         byteReader.contentLength
 
-    override val position: Int
-        get() = currentPosition
-
-    override val available: Long
-        get() = contentLength - position
-
     private var currentPosition: Int = 0
 
     private val buffer: MutableList<Byte> = ArrayList(INITIAL_SIZE)
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReader.kt b/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReader.kt
deleted file mode 100644
index e9c1812c..00000000
--- a/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReader.kt
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * Copyright 2024 Ashampoo GmbH & Co. KG
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.ashampoo.kim.input
-
-interface PositionTrackingByteReader : ByteReader {
-
-    val position: Int
-
-    val available: Long
-
-}
diff --git a/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReaderDecorator.kt b/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReaderDecorator.kt
deleted file mode 100644
index 3579303b..00000000
--- a/src/commonMain/kotlin/com/ashampoo/kim/input/PositionTrackingByteReaderDecorator.kt
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- * Copyright 2024 Ashampoo GmbH & Co. KG
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.ashampoo.kim.input
-
-/**
- * This is a Decorator to track the current position in reading the file.
- *
- * The ByteReader interface has many complex implementations, where some
- * of them aren't even aware of the current position or the position tracking
- * is an implementation detail that should not be exposed.
- * Therefore it's better to track the position on a higher level.
- */
-class PositionTrackingByteReaderDecorator(
-    val byteReader: ByteReader
-) : PositionTrackingByteReader {
-
-    override val contentLength: Long =
-        byteReader.contentLength
-
-    override val position: Int
-        get() = currentPosition
-
-    override val available: Long
-        get() = byteReader.contentLength - position
-
-    private var currentPosition: Int = 0
-
-    override fun readByte(): Byte? {
-
-        val byte = byteReader.readByte()
-
-        if (byte != null)
-            currentPosition++
-
-        return byte
-    }
-
-    override fun readBytes(count: Int): ByteArray {
-
-        val bytes = byteReader.readBytes(count)
-
-        currentPosition += bytes.size
-
-        return bytes
-    }
-
-    override fun close() {
-        /* Do nothing */
-    }
-}
diff --git a/src/commonTest/kotlin/com/ashampoo/kim/format/bmff/BoxReaderTest.kt b/src/commonTest/kotlin/com/ashampoo/kim/format/bmff/BoxReaderTest.kt
index 4e1a476a..e9385824 100644
--- a/src/commonTest/kotlin/com/ashampoo/kim/format/bmff/BoxReaderTest.kt
+++ b/src/commonTest/kotlin/com/ashampoo/kim/format/bmff/BoxReaderTest.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2023 Ashampoo GmbH & Co. KG
+ * Copyright 2024 Ashampoo GmbH & Co. KG
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,7 +18,6 @@ package com.ashampoo.kim.format.bmff
 
 import com.ashampoo.kim.format.bmff.box.BoxContainer
 import com.ashampoo.kim.input.ByteArrayByteReader
-import com.ashampoo.kim.input.PositionTrackingByteReaderDecorator
 import com.ashampoo.kim.testdata.KimTestData
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -30,7 +29,7 @@ class BoxReaderTest {
 
         val bytes = KimTestData.getBytesOf(KimTestData.HEIC_TEST_IMAGE_INDEX)
 
-        val byteReader = PositionTrackingByteReaderDecorator(ByteArrayByteReader(bytes))
+        val byteReader = ByteArrayByteReader(bytes)
 
         val boxes = BoxReader.readBoxes(
             byteReader = byteReader,
@@ -44,7 +43,7 @@ class BoxReaderTest {
         assertEquals(48, allBoxes.first { it.type == BoxType.HDLR }.offset)
         assertEquals(118, allBoxes.first { it.type == BoxType.PITM }.offset)
         assertEquals(132, allBoxes.first { it.type == BoxType.IINF }.offset)
-        assertEquals(146, allBoxes.first { it.type == BoxType.INFE }.offset)
+        assertEquals(144, allBoxes.first { it.type == BoxType.INFE }.offset)
         assertEquals(2572, allBoxes.first { it.type == BoxType.ILOC }.offset)
         assertEquals(3404, allBoxes.first { it.type == BoxType.MDAT }.offset)
     }