How to extract multiple images contained in HEIC file format?

Wait? Now the png has lots of files? xD Please don’t make fun of us.

Btw here is the full metadata:

Big Sur.heic

<x:xmpmeta
	xmlns:x="adobe:ns:meta/" x:xmptk="XMP Core 6.0.0">
	<rdf:RDF
		xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
		<rdf:Description rdf:about="" xm
lns:aux="http://ns.adobe.com/exif/1.0/aux/"
			xmlns:dc="http://purl.org/dc/elements/1.1/"
			xmlns:xmp="http://ns.adobe.com/xap/1.0/"
			xmlns:xmpDM="http://ns.adobe.com/xmp/1.0/DynamicMedia/"
			xmlns:xmpMM="http://ns.ad
obe.com/xap/1.0/mm/"
			xmlns:stEvt="http://ns.adobe.com/xap/1.0/sType/ResourceEvent#"
			xmlns:stRef="http://ns.adobe.com/xap/1.0/sType/ResourceRef#"
			xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/"
			xmlns:xmpNot
e="http://ns.adobe.com/xmp/note/" aux:SerialNumber="JD010744" aux:LensSerialNumber="TF001846" aux:LensInfo="0/1 0/1 157525/56259 1029841/46811" aux:Lens="Schneider LS 55mm f/2.8" aux:ImageNumber="31129" aux:Firmware="IQ4 150MP, v5.01.0 (FWP)" dc:format="image/jpeg" xmp:MetadataDate="2020-08-20T23:12:15-10:00" xmp:CreatorTool="Adobe Photoshop 21.2 (Macintosh)" xmp:CreateDate="2019-11-06T08:01:25" xmp:ModifyDate="2020-
08-20T23:12:15-10:00" xmpDM:cameraModel="XF" xmpMM:OriginalDocumentID="xmp.did:0b1857e0-9788-6a46-9c04-fdb1b39791e5" xmpMM:InstanceID="xmp.iid:f26d88c7-6397-4775-adab-cc4f956f1cac" xmpMM:DocumentID="adobe:docid:photoshop:4ded6604-d5c9-fe45-97af-9b5851d7164e" photoshop:ColorMode="3" photoshop:ICCProfile="image P3" photoshop:LegacyIPTCDigest="4A1906169B00B54BBC60DC1A5152A72D" photoshop:DateCreated="2019-11-06T08:01:25" xmpNote:HasExtendedXMP="FF26175B7A58850FE751097F554232A8">
			<xmpMM:History>
				<rdf:Seq>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-03-12T16:05:06-07:00" stEvt:instanceID="xmp.iid:0b1857e0-9788-6a46-9c04-fdb1b39791e5" stEvt:action="saved"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-23T05:47:37-07:00" stEvt:instanceID="xmp.iid:64a98aea-8277-9048-a638-cf143888b36e" stEvt:action="saved"/>
					<rdf:li stEvt:action="converted" stEvt:parameters="from application/vnd.adobe.photoshop to image/png"/>
					<rdf:li stEvt:action="derived" stEvt:parameters="converted from application/vnd.adobe.photoshop to image/png"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-23T05:47:37-07:00" stEvt:instanceID="xmp.iid:82e2e4a2-72c1-d447-b679-8636645c8e01" stEvt:action="saved"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-23T18:58:31-07:00" stEvt:instanceID="xmp.iid:3a3d8ea2-46f6-ca4f-9c57-9a169903847a" stEvt:action="saved"/>
					<rdf:li stEvt:action="converted" stEvt:parameters="from image/png to application/vnd.adobe.photoshop"/>
					<rdf:li stEvt:action="derived" stEvt:parameters="converted from image/png to application/vnd.adobe.photoshop"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-23T18:58:31-07:00" stEvt:instanceID="xmp.iid:86ef9e06-0f62-0848-be49-9eca2e0cb291" stEvt:action="saved"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-27T13:41:37-07:00" stEvt:instanceID="xmp.iid:4c189ef4-768d-bf49-a3ad-a26b8c6592cd" stEvt:action="saved"/>
					<rdf:li stEvt:action="converted" stEvt:parameters="from application/vnd.adobe.photoshop to image/png"/>
					<rdf:li stEvt:action="derived" stEvt:parameters="converted from application/vnd.adobe.photoshop to image/png"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop CC 2019 (Windows)" stEvt:changed="/" stEvt:when="2020-04-27T13:41:37-07:00" stEvt:instanceID="xmp.iid:e0bb8ad7-3d0e-d743-8c20-e5c5a6e4d62f" stEvt:action="saved"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop 21.2 (Macintosh)" stEvt:changed="/" stEvt:when="2020-08-20T23:12:15-10:00" stEvt:instanceID="xmp.iid:58f37e07-588d-4ca0-9b84-241806a91218" stEvt:action="saved"/>
					<rdf:li stEvt:action="converted" stEvt:parameters="from image/png to image/jpeg"/>
					<rdf:li stEvt:action="derived" stEvt:parameters="converted from image/png to image/jpeg"/>
					<rdf:li stEvt:softwareAgent="Adobe Photoshop 21.2 (Macintosh)" stEvt:changed="/" stEvt:when="2020-08-20T23:12:15-10:00" stEvt:instanceID="xmp.iid:f26d88c7-6397-4775-adab-cc4f956f1cac" stEvt:action="saved"/>
				</rdf:Seq>
			</xmpMM:History>
			<xmpMM:DerivedFrom stRef:originalDocumentID="xmp.did:0b1857e0-9788-6a46-9c04-fdb1b39791e5" stRef:instanceID="xmp.iid:58f37e07-588d-4ca0-9b84-241806a91218" stRef:documentID="adobe:docid:photoshop:6f2647b7-0045-d84a-95f2-e3445a8574e5"/>
		</rdf:Description>
	</rdf:RDF>
</x:xmpmeta>

Big Sur.png

   <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:Description rdf:about=""
            xmlns:apple_desktop="http://ns.apple.com/namespace/1.0/"
            xmlns:tiff="http://ns.adobe.com/tiff/1.0/">
         <apple_desktop:solar>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</apple_desktop:solar>
         <tiff:TileWidth>1024</tiff:TileWidth>
         <tiff:TileLength>1024</tiff:TileLength>
         <tiff:Orientation>1</tiff:Orientation>
      </rdf:Description>
   </rdf:RDF>
</x:xmpmeta>

Both were made with photoshop. and Both just contain one image.

No… it is a really high resolution lossless image (6016x6016):

$ file Big\ Sur.png 
Big Sur.png: PNG image data, 6016 x 6016, 8-bit/color RGBA, non-interlaced

:wink: