diff --git a/data/brands.csv b/data/brands.csv
index c7a69cc..07e2cb4 100644
--- a/data/brands.csv
+++ b/data/brands.csv
@@ -283,6 +283,7 @@ geo1,The file is conformant to version 1 of NGA.STND.0076-01_V1.0_GIMI,NGA.STND.
sm01,The file carries GIMI Security XML markings,NGA.STND.0076
jaii,JPEG AI coded image,JPEGAI
SAV1,ISOBMFF brand for Static Audible Verified X profile,SAVX
+tmap,Tone-map derived image item present,HEIF
ca4e,CMAF Media Profile - AC-4 subsample encrypted,ETSI AC-4
dv58,Dolby Vision Profile 5/8 CMAF Media Profile,Dolby Vision
dv09,Dolby Vision Profile 9 CMAF Media Profile,Dolby Vision
diff --git a/data/entity-groups.csv b/data/entity-groups.csv
index 3568360..fedaf11 100644
--- a/data/entity-groups.csv
+++ b/data/entity-groups.csv
@@ -25,3 +25,6 @@ vipo,Viewpoint entity grouping,OMAF
vvcb,VVC bitstream,NALu Video
wbbr,White balance bracketing entity group,HEIF
prsl,Preselection grouping,ISO
+stem,Stereo pair with monoscopic fallback,HEIF
+pymd,Image pyramid,HEIF
+rgpa,Region partition group,HEIF
diff --git a/data/item-properties.csv b/data/item-properties.csv
index d7c848c..99d8197 100644
--- a/data/item-properties.csv
+++ b/data/item-properties.csv
@@ -79,3 +79,8 @@ nnrC,Configuration item property for 'nnr1' item,NALu Video
taic,TAI clock information box,UNCV
itai,Item TAI timestamps,UNCV
jaih,JPEG AI header item property,JPEGAI
+cexg,Constrained extents grid,HEIF
+dadj,Disparity adjustment,HEIF
+stag,Stereo aggressors,HEIF
+reve,Reference viewing environment,HEIF
+ndwt,Nominal diffuse white,HEIF
diff --git a/data/item-references.csv b/data/item-references.csv
index db52f5c..28d2e39 100644
--- a/data/item-references.csv
+++ b/data/item-references.csv
@@ -17,4 +17,4 @@ prem,Pre-Multiplied item,item ref.,MIAF
tbas,HEVC Tile track base item reference,item ref.,HEIF
thmb,Thumbnail image item reference,item ref.,HEIF
auxr,Auxiliary information item reference,item ref.,CENC
-sato,Sample Transform Derived Image Items combine input pixel values using basic mathematical operations,item ref.,AVIF
+rpds,Region partition group reference,item ref.,HEIF
diff --git a/data/item-types.csv b/data/item-types.csv
index 37bbbf7..0f05b50 100644
--- a/data/item-types.csv
+++ b/data/item-types.csv
@@ -1,25 +1,28 @@
-code,description,specification
-auvd,Auxiliary Video descriptor,ISO
-av01,AVIF image item,AVIF
-avc1,AVC image item,HEIF
-Exif,EXIF item,HEIF
-evc1,EVC image item,HEIF
-grid,Image item grid derivation,HEIF
-hvc1,HEVC image item,HEIF
-hvt1,HEVC tile image item,HEIF
-iden,Image item identity derivation,HEIF
-iovl,Image item overlay derivation,HEIF
-j2k1,Contiguous Codestream box as specified in Rec. ITU-T T.800 | ISO/IEC 15444-1,J2KHEIF
-jpeg,JPEG image item,HEIF
-jxs1,Images coded to the JPEG-XS coding format,JPXS
-lhv1,Layered HEVC image item,HEIF
-mint,Data integrity item,HEIF
-mime,Item identified by a MIME type,ISO
-mski,Mask item,HEIF
-rgan,Region item,HEIF
-vvc1,VVC image item,HEIF
-unci,Uncompressed Image Item,UNCV
-it35,T.35 Item,ISO
-nnr1,"NNR Item that carries a bitstream conforming to ISO/IEC 15398-17 (Neural Network Representation NNR, also known as Neural Network Coding, NNC)",NALu Video
-auxi,Auxiliary information item,CENC
-jai0,JPEG AI coded image item,JPEGAI
+code,description,type,specification
+auvd,Auxiliary Video descriptor,metadata,ISO
+av01,AVIF image item,coded,AVIF
+avc1,AVC image item,coded,HEIF
+Exif,EXIF item,metadata,HEIF
+evc1,EVC image item,coded,HEIF
+grid,Image item grid derivation,derived,HEIF
+hvc1,HEVC image item,coded,HEIF
+hvt1,HEVC tile image item,coded,HEIF
+iden,Image item identity derivation,derived,HEIF
+iovl,Image item overlay derivation,derived,HEIF
+j2k1,Contiguous Codestream box as specified in Rec. ITU-T T.800 | ISO/IEC 15444-1,coded,J2KHEIF
+jpeg,JPEG image item,coded,HEIF
+jxs1,Images coded to the JPEG-XS coding format,coded,JPXS
+lhv1,Layered HEVC image item,coded,HEIF
+mint,Data integrity item,metadata,HEIF
+mime,Item identified by a MIME type,metadata,ISO
+mski,Mask item,coded,HEIF
+rgan,Region item,metadata,HEIF
+vvc1,VVC image item,coded,HEIF
+unci,Uncompressed Image Item,coded,UNCV
+it35,T.35 Item,metadata,ISO
+nnr1,"NNR Item that carries a bitstream conforming to ISO/IEC 15398-17 (Neural Network Representation NNR, also known as Neural Network Coding, NNC)",coded,NALu Video
+auxi,Auxiliary information item,metadata,CENC
+jai0,JPEG AI coded image item,coded,JPEGAI
+sato,Sample Transform derived image item,derived,AVIF
+tmap,Tone-map derived image item,derived,HEIF
+cfen,Colour format enhancement derived image item,derived,HEIF
diff --git a/src/app/(rest)/registered-types/item-properties/page.mdx b/src/app/(rest)/registered-types/item-properties/page.mdx
index 481d278..3596f19 100644
--- a/src/app/(rest)/registered-types/item-properties/page.mdx
+++ b/src/app/(rest)/registered-types/item-properties/page.mdx
@@ -6,6 +6,8 @@ export const metadata = {
# Item Properties
-This section documents the item property types, which are elements of the `ItemPropertyContainerBox`.
+Item properties are small data records stored in the `ItemPropertyContainerBox` ('ipco') and associated with items via the `ItemPropertyAssociation` ('ipma'). Each property is identified by its box type and provides descriptive or transformative metadata for the associated item.
+
+See also the consolidated [Items](/registered-types/items) page.
diff --git a/src/app/(rest)/registered-types/items/page.mdx b/src/app/(rest)/registered-types/items/page.mdx
new file mode 100644
index 0000000..4a15df3
--- /dev/null
+++ b/src/app/(rest)/registered-types/items/page.mdx
@@ -0,0 +1,29 @@
+import { DataDisplay } from "@/components";
+
+export const metadata = {
+ title: "Items"
+};
+
+# Items
+
+The ISO base media file format (ISO/IEC 14496-12) defines an item model within the `MetaBox` for storing non-timed data such as images, metadata documents, and derived content. Each item is described by an `ItemInfoEntry` that declares its `item_type` — a four-character code identifying the format of the item's data.
+
+Items can be associated with properties and linked to other items through typed references, enabling complex relationships such as thumbnails, auxiliary images, and derived image constructions.
+
+## Item types
+
+The `item_type` in the `ItemInfoEntry` identifies the coding format or role of an item. For example, an HEVC coded image uses item type `hvc1`, while Exif metadata uses `Exif`.
+
+
+
+## Item properties
+
+Item properties are small data records stored in the `ItemPropertyContainerBox` ('ipco') and associated with items via the `ItemPropertyAssociation` ('ipma'). Each property is identified by its box type and provides descriptive or transformative metadata for the associated item (e.g., image dimensions, rotation, colour information).
+
+
+
+## Item references
+
+Item references in the `ItemReferenceBox` ('iref') define typed links between items. Each reference type is a four-character code indicating the relationship (e.g., `thmb` for thumbnail, `dimg` for derived image source, `auxl` for auxiliary image).
+
+