1. MEMORY INSTITUTIONS AND DIGITAL TRANSFORMATION
1.1 Memory Institutions (GLAM)
Memory institutions—Galleries, Libraries, Archives, and Museums (GLAM)—are
responsible for preserving and transmitting cultural memory. In the digital age, their role
increasingly involves digital infrastructures.
Digital transformation in GLAM includes:
• Digitisation of collections
• Creation and management of metadata
• Adoption of standards and interoperability frameworks
• Long-term digital preservation
1.2 Types of Digital Heritage Collections
Data includes any kind of information, regardless of medium: text, numbers, images,
audio… Data can be analog or digital.
Born-Digital Collections
Born-digital materials are created natively in digital form. Examples include:
• Emails, websites, social media content
• Digital photographs and GIS datasets
• Net art Term – Net Art:
A form of contemporary art made for and experienced on the internet. It
challenges traditional museum display by existing purely in digital space
These collections raise specific challenges related to software dependency, format
obsolescence, and long-term accessibility.
Digitised Collections
Digitised collections originate as physical objects and are later converted into digital
form. Examples include:
• Scanned photographs and manuscripts
• Digitised maps and plans
• 3D scans of objects or monuments
Digitisation is not merely scanning. It also involves:
• Metadata creation
• Annotation and categorisation
• Quality control
• Preservation planning
,2. INTERNATIONAL SHARING AND IIIF
2.1 The problem: high-quality access across institutions
Digital heritage content is often distributed across many institutions, each with its own:
• repositories
• platforms
• metadata practices
• access and rights conditions
This creates tension between:
• institutional control (authenticity, rights, preservation)
• public access and reuse
2.2 IIIF – International Image Interoperability Framework
IIIF is a global framework that standardises how institutions deliver and share high-
quality digital images online and across institutions. It enables users to
• zoom deeply into images
• compare items from diTerent institutions in one interface
• annotate and share objects across systems
3. DIGITISATION AS DATA TRANSFORMATION
Digitisation transforms analog heritage into data. This process involves technical and
conceptual decisions that directly aTect:
• Image or text quality
• Interpretability
• Reusability
• Long-term preservation
Digitisation is therefore never neutral: choices made during digitisation shape future
research possibilities and interpretations.
4. IMAGES IN DIGITAL HERITAGE
4.1 Born-Analog and Digital Images
In analog photography, light reflects oT the subject and passes through the camera
lens, exposing a light-sensitive film. Through chemical processes the film is developed
and fixed.
In digital photography, the camera lens directs light onto an electronic image sensor
(such as a CCD or CMOS). Each sensor element converts the light into an electrical
signal, which is processed into a digital file.
Images can exist in multiple combinations:
• Analog stored as analog (film photograph)
• Analog stored as digital (scanned image)
, • Digital stored as digital (digital photo)
• Digital stored as analog (printed digital image)
This demonstrates the two-way flow between physical and digital media.
! not all images are photographic. There are many non-photographic images created
through other techniques or technologies (computer). They are semi-photographic.
4.2 Sampling and Quantisation
Two processes define digital image quality:
• Sampling: determines spatial resolution (number of pixels). Transforming an
analog image into a digital grid of pixels.
• Quantisation: determines colour or tonal resolution (bit depth). analyses the
average darkness or brightness of each pixel and assigns it a numerical value
(binary number), each of them have a diTerent value and that’s how you encode
them.
4.3 Sampling
The sampling rate determines how many pixels represent the original scene.
• A higher sampling rate → higher resolution (dpi or ppi) and more detail and
smaller picture
• A lower sampling rate → lower resolution (dpi or ppi) and loss of detail and bigger
picture
è sample rate = pixel density = resolution -> higher sampling rate = more pixels =
better detail = bigger file size.
4.4 Quantisation
The number of possible values depends on the bit depth:
• 1-bit → 2 values (0=black & 1=white). It’s or white or black.
• 8-bit (2⁸) → 256 values (grayscale) 0 = black, 255 = white
• 24-bit (True Color) → 16.7 million colours (used for photorealistic images and
• video). 8 bits for red, 8 bits for green, 8 bits for blue.
è The more bits per pixel, the more quantisation levels there are, which improves
colour
accuracy but requires more storage space.
4.5 Preservation Logic
A core rule in digital heritage imaging is:
Capture high – work high – distribute low
Institutions digitise at high resolution (600dpi and 16-bit) to prevent irreversible loss of
heritage information.
1.1 Memory Institutions (GLAM)
Memory institutions—Galleries, Libraries, Archives, and Museums (GLAM)—are
responsible for preserving and transmitting cultural memory. In the digital age, their role
increasingly involves digital infrastructures.
Digital transformation in GLAM includes:
• Digitisation of collections
• Creation and management of metadata
• Adoption of standards and interoperability frameworks
• Long-term digital preservation
1.2 Types of Digital Heritage Collections
Data includes any kind of information, regardless of medium: text, numbers, images,
audio… Data can be analog or digital.
Born-Digital Collections
Born-digital materials are created natively in digital form. Examples include:
• Emails, websites, social media content
• Digital photographs and GIS datasets
• Net art Term – Net Art:
A form of contemporary art made for and experienced on the internet. It
challenges traditional museum display by existing purely in digital space
These collections raise specific challenges related to software dependency, format
obsolescence, and long-term accessibility.
Digitised Collections
Digitised collections originate as physical objects and are later converted into digital
form. Examples include:
• Scanned photographs and manuscripts
• Digitised maps and plans
• 3D scans of objects or monuments
Digitisation is not merely scanning. It also involves:
• Metadata creation
• Annotation and categorisation
• Quality control
• Preservation planning
,2. INTERNATIONAL SHARING AND IIIF
2.1 The problem: high-quality access across institutions
Digital heritage content is often distributed across many institutions, each with its own:
• repositories
• platforms
• metadata practices
• access and rights conditions
This creates tension between:
• institutional control (authenticity, rights, preservation)
• public access and reuse
2.2 IIIF – International Image Interoperability Framework
IIIF is a global framework that standardises how institutions deliver and share high-
quality digital images online and across institutions. It enables users to
• zoom deeply into images
• compare items from diTerent institutions in one interface
• annotate and share objects across systems
3. DIGITISATION AS DATA TRANSFORMATION
Digitisation transforms analog heritage into data. This process involves technical and
conceptual decisions that directly aTect:
• Image or text quality
• Interpretability
• Reusability
• Long-term preservation
Digitisation is therefore never neutral: choices made during digitisation shape future
research possibilities and interpretations.
4. IMAGES IN DIGITAL HERITAGE
4.1 Born-Analog and Digital Images
In analog photography, light reflects oT the subject and passes through the camera
lens, exposing a light-sensitive film. Through chemical processes the film is developed
and fixed.
In digital photography, the camera lens directs light onto an electronic image sensor
(such as a CCD or CMOS). Each sensor element converts the light into an electrical
signal, which is processed into a digital file.
Images can exist in multiple combinations:
• Analog stored as analog (film photograph)
• Analog stored as digital (scanned image)
, • Digital stored as digital (digital photo)
• Digital stored as analog (printed digital image)
This demonstrates the two-way flow between physical and digital media.
! not all images are photographic. There are many non-photographic images created
through other techniques or technologies (computer). They are semi-photographic.
4.2 Sampling and Quantisation
Two processes define digital image quality:
• Sampling: determines spatial resolution (number of pixels). Transforming an
analog image into a digital grid of pixels.
• Quantisation: determines colour or tonal resolution (bit depth). analyses the
average darkness or brightness of each pixel and assigns it a numerical value
(binary number), each of them have a diTerent value and that’s how you encode
them.
4.3 Sampling
The sampling rate determines how many pixels represent the original scene.
• A higher sampling rate → higher resolution (dpi or ppi) and more detail and
smaller picture
• A lower sampling rate → lower resolution (dpi or ppi) and loss of detail and bigger
picture
è sample rate = pixel density = resolution -> higher sampling rate = more pixels =
better detail = bigger file size.
4.4 Quantisation
The number of possible values depends on the bit depth:
• 1-bit → 2 values (0=black & 1=white). It’s or white or black.
• 8-bit (2⁸) → 256 values (grayscale) 0 = black, 255 = white
• 24-bit (True Color) → 16.7 million colours (used for photorealistic images and
• video). 8 bits for red, 8 bits for green, 8 bits for blue.
è The more bits per pixel, the more quantisation levels there are, which improves
colour
accuracy but requires more storage space.
4.5 Preservation Logic
A core rule in digital heritage imaging is:
Capture high – work high – distribute low
Institutions digitise at high resolution (600dpi and 16-bit) to prevent irreversible loss of
heritage information.
