feat: define DigitalSourceType as enum

sdk/examples/c2pa.toml

@@ -90,7 +90,7 @@ action = "c2pa.edited"
 # The source type field is required for the c2pa.created action.
 #
 # For more information, see `c2pa::assertions::actions::source_type`.
-source_type = "http://c2pa.org/digitalsourcetype/empty"
+source_type = "empty"
 # Description for the action
 description = "Some edit action."
 # Arbitrary key/value pairs to store in the action.
@@ -122,7 +122,7 @@ enabled = true
 # The source type field is required for the c2pa.created action.
 #
 # For more information, see `c2pa::assertions::actions::source_type`.
-source_type = "http://c2pa.org/digitalsourcetype/empty"
+source_type = "empty"
 
 # Settings for configuring how c2pa.opened actions are auto created.
 #
@@ -134,7 +134,7 @@ enabled = true
 # For more information, see `c2pa::assertions::actions::source_type`.
 #
 # Note this field is optional for the c2pa.opened action.
-source_type = "http://c2pa.org/digitalsourcetype/empty"
+source_type = "empty"
 
 # Settings for configuring how c2pa.placed actions are auto created.
 #
@@ -146,7 +146,7 @@ enabled = true
 # For more information, see `c2pa::assertions::actions::source_type`.
 #
 # Note this field is optional for the c2pa.placed action.
-source_type = "http://c2pa.org/digitalsourcetype/empty"
+source_type = "empty"
 
 # Settings for automatic thumbnail generation.
 [builder.thumbnail]

sdk/src/assertions/actions.rs

@@ -11,7 +11,7 @@
 // specific language governing permissions and limitations under
 // each license.
 
-use std::collections::HashMap;
+use std::{collections::HashMap, fmt};
 
 use log::error;
 use serde::{Deserialize, Serialize};
@@ -29,19 +29,176 @@ use crate::{
 const ASSERTION_CREATION_VERSION: usize = 2;
 pub const CAI_INGREDIENT_IDS: &str = "org.cai.ingredientIds";
 
-// TODO: make enum
-/// Constants indicating from which source a digital image was created.
-///
-/// These constants are used in conjunction with [`Actions::source_type`].
-#[allow(unused)]
-pub(crate) mod source_type {
-    /// Media whose digital content is effectively empty, such as a blank canvas or zero-length video.
-    pub const EMPTY: &str = "http://c2pa.org/digitalsourcetype/empty";
-    /// Data that is the result of algorithmically using a model derived from sampled content and data.
-    /// Differs from <http://cv.iptc.org/newscodes/digitalsourcetype/>trainedAlgorithmicMedia in that
-    /// the result isn’t a media type (e.g., image or video) but is a data format (e.g., CSV, pickle).
-    pub const TRAINED_ALGORITHMIC_DATA: &str =
-        "http://c2pa.org/digitalsourcetype/trainedAlgorithmicData";
+// TODO: this is needed to supress clippy deprecated field warning:  https://github.com/serde-rs/serde/pull/2879
+pub use digital_source_type::DigitalSourceType;
+mod digital_source_type {
+    #![allow(deprecated)]
+
+    #[cfg(feature = "json_schema")]
+    use schemars::JsonSchema;
+
+    use super::*;
+
+    /// Description of the source of an asset.
+    ///
+    /// The full list of possible digital source types are found below:
+    /// <https://spec.c2pa.org/specifications/specifications/2.2/specs/C2PA_Specification.html#_digital_source_type>
+    /// <https://cv.iptc.org/newscodes/digitalsourcetype>
+    #[non_exhaustive]
+    #[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+    #[cfg_attr(feature = "json_schema", derive(JsonSchema))]
+    pub enum DigitalSourceType {
+        /// Media whose digital content is effectively empty, such as a blank canvas or zero-length video.
+        #[serde(alias = "empty", rename = "http://c2pa.org/digitalsourcetype/empty")]
+        Empty,
+        /// Data that is the result of algorithmically using a model derived from sampled content and data.
+        /// Differs from <http://cv.iptc.org/newscodes/digitalsourcetype/>trainedAlgorithmicMedia in that
+        /// the result isn’t a media type (e.g., image or video) but is a data format (e.g., CSV, pickle).
+        #[serde(
+            alias = "trainedAlgorithmicData",
+            rename = "http://c2pa.org/digitalsourcetype/trainedAlgorithmicData"
+        )]
+        TrainedAlgorithmicData,
+        /// The media was captured from a real-life source using a digital camera or digital recording device.
+        #[serde(
+            alias = "digitalCapture",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/digitalCapture"
+        )]
+        DigitalCapture,
+        /// The media is the result of capturing multiple frames from a real-life source using a digital camera
+        /// or digital recording device, then automatically merging them into a single frame using digital signal
+        /// processing techniques and/or non-generative AI. Includes High Dynamic Range (HDR) processing common in
+        /// smartphone camera apps.
+        #[serde(
+            alias = "computationalCapture",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/computationalCapture"
+        )]
+        ComputationalCapture,
+        /// The media was digitised from a negative on film or other transparent medium.
+        #[serde(
+            alias = "negativeFilm",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/negativeFilm"
+        )]
+        NegativeFilm,
+        /// The media was digitised from a positive on a transparency or other transparent medium.
+        #[serde(
+            alias = "positiveFilm",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/positiveFilm"
+        )]
+        PositiveFilm,
+        /// The media was digitised from a non-transparent medium such as a photographic print.
+        #[serde(
+            alias = "print",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/print"
+        )]
+        Print,
+        /// Minor augmentation or correction by a human, such as a digitally-retouched photo used in a magazine.
+        #[deprecated]
+        #[serde(
+            alias = "minorHumanEdits",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/minorHumanEdits"
+        )]
+        MinorHumanEdits,
+        /// Augmentation, correction or enhancement by one or more humans using non-generative tools.
+        #[serde(
+            alias = "humanEdits",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/humanEdits"
+        )]
+        HumanEdits,
+        /// Augmentation, correction or enhancement using a Generative AI model, such as with inpainting or
+        /// outpainting operations.
+        #[serde(
+            alias = "compositeWithTrainedAlgorithmicMedia",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/compositeWithTrainedAlgorithmicMedia"
+        )]
+        CompositeWithTrainedAlgorithmicMedia,
+        /// Modification or correction by algorithm without changing the main content of the media, initiated
+        /// or configured by a human, such as sharpening or applying noise reduction.
+        #[serde(
+            alias = "algorithmicallyEnhanced",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/algorithmicallyEnhanced"
+        )]
+        AlgorithmicallyEnhanced,
+        /// The digital image was created by computer software.
+        #[deprecated]
+        #[serde(
+            alias = "softwareImage",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/softwareImage"
+        )]
+        SoftwareImage,
+        /// Media created by a human using digital tools.
+        #[deprecated]
+        #[serde(
+            alias = "digitalArt",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/digitalArt"
+        )]
+        DigitalArt,
+        /// Media created by a human using non-generative tools.
+        #[serde(
+            alias = "digitalCreation",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/digitalCreation"
+        )]
+        DigitalCreation,
+        /// Digital media representation of data via human programming or creativity.
+        #[serde(
+            alias = "dataDrivenMedia",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/dataDrivenMedia"
+        )]
+        DataDrivenMedia,
+        /// Digital media created algorithmically using an Artificial Intelligence model trained on captured
+        /// content.
+        #[serde(
+            alias = "trainedAlgorithmicMedia",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/trainedAlgorithmicMedia"
+        )]
+        TrainedAlgorithmicMedia,
+        /// Media created purely by an algorithm not based on any sampled training data, e.g. an image created
+        /// by software using a mathematical formula.
+        #[serde(
+            alias = "algorithmicMedia",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/algorithmicMedia"
+        )]
+        AlgorithmicMedia,
+        /// A capture of the contents of the screen of a computer or mobile device.
+        #[serde(
+            alias = "screenCapture",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/screenCapture"
+        )]
+        ScreenCapture,
+        /// Live recording of virtual event based on Generative AI and/or captured elements.
+        #[serde(
+            alias = "virtualRecording",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/virtualRecording"
+        )]
+        VirtualRecording,
+        /// Mix or composite of several elements, any of which may or may not be generative AI.
+        #[serde(
+            alias = "composite",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/composite"
+        )]
+        Composite,
+        /// Mix or composite of several elements that are all captures of real life.
+        #[serde(
+            alias = "compositeCapture",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/compositeCapture"
+        )]
+        CompositeCapture,
+        /// Mix or composite of several elements, at least one of which is Generative AI.
+        #[serde(
+            alias = "compositeSynthetic",
+            rename = "http://cv.iptc.org/newscodes/digitalsourcetype/compositeSynthetic"
+        )]
+        CompositeSynthetic,
+        /// An unknown digital source type.
+        #[serde(untagged)]
+        Other(String),
+    }
+
+    impl fmt::Display for DigitalSourceType {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            self.serialize(f)
+        }
+    }
 }
 
 /// C2PA actions defined in the C2PA specification.
@@ -188,7 +345,7 @@ pub struct Action {
 
     /// One of the defined URI values at `<https://cv.iptc.org/newscodes/digitalsourcetype/>`
     #[serde(rename = "digitalSourceType", skip_serializing_if = "Option::is_none")]
-    pub(crate) source_type: Option<String>,
+    pub(crate) source_type: Option<DigitalSourceType>,
 
     /// List of related actions.
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -281,8 +438,8 @@ impl Action {
 
     /// Returns a digitalSourceType as defined at <https://cv.iptc.org/newscodes/digitalsourcetype/>.
     // QUESTION: Keep in docs?
-    pub fn source_type(&self) -> Option<&str> {
-        self.source_type.as_deref()
+    pub fn source_type(&self) -> Option<&DigitalSourceType> {
+        self.source_type.as_ref()
     }
 
     /// Returns the list of related actions.
@@ -418,8 +575,8 @@ impl Action {
     }
 
     /// Set a digitalSourceType URI as defined at <https://cv.iptc.org/newscodes/digitalsourcetype/>.
-    pub fn set_source_type<S: Into<String>>(mut self, uri: S) -> Self {
-        self.source_type = Some(uri.into());
+    pub fn set_source_type<T: Into<DigitalSourceType>>(mut self, source_type: T) -> Self {
+        self.source_type = Some(source_type.into());
         self
     }
 
@@ -503,7 +660,7 @@ impl Action {
     }
 }
 
-#[derive(Deserialize, Serialize, Debug, Clone, Default, PartialEq, Eq)]
+#[derive(Deserialize, Serialize, Debug, Clone, Default, PartialEq)]
 #[non_exhaustive]
 pub struct ActionTemplate {
     /// The label associated with this action. See ([`c2pa_action`]).
@@ -519,7 +676,7 @@ pub struct ActionTemplate {
 
     /// One of the defined URI values at `<https://cv.iptc.org/newscodes/digitalsourcetype/>`
     #[serde(rename = "digitalSourceType", skip_serializing_if = "Option::is_none")]
-    pub source_type: Option<String>,
+    pub source_type: Option<DigitalSourceType>,
 
     #[serde(skip_serializing_if = "Option::is_none")]
     pub icon: Option<UriOrResource>,
@@ -756,7 +913,7 @@ pub mod tests {
                     .set_parameter("name".to_owned(), "gaussian blur")
                     .unwrap()
                     .set_when("2015-06-26T16:43:23+0200")
-                    .set_source_type("digsrctype:algorithmicMedia")
+                    .set_source_type(DigitalSourceType::AlgorithmicMedia)
                     .add_change(RegionOfInterest {
                         region: vec![Range {
                             range_type: RangeType::Temporal,
@@ -797,7 +954,7 @@ pub mod tests {
         assert_eq!(result.actions[1].when(), original.actions[1].when());
         assert_eq!(
             result.actions[1].source_type().unwrap(),
-            "digsrctype:algorithmicMedia"
+            &DigitalSourceType::AlgorithmicMedia
         );
         assert_eq!(result.actions[1].changes(), original.actions()[1].changes());
         assert_eq!(

sdk/src/assertions/mod.rs

@@ -14,10 +14,8 @@
 //! Assertion helpers to build, validate, and parse assertions.
 
 mod actions;
-#[allow(unused)]
-pub(crate) use actions::source_type;
 pub(crate) use actions::V2_DEPRECATED_ACTIONS;
-pub use actions::{c2pa_action, Action, ActionTemplate, Actions, SoftwareAgent};
+pub use actions::{c2pa_action, Action, ActionTemplate, Actions, DigitalSourceType, SoftwareAgent};
 
 mod asset_reference;
 pub use asset_reference::AssetReference;