Merge #6207: M11: PDF/A verify reports transfer functions, halftones and rendering intents a graphics state may not use (optimize.pdfa-validate)

# Conflicts:
#	crates/preflight/src/lib.rs
#	crates/preflight/src/tests.rs
#	parity/acrobat-features.toml

crates/preflight/src/gstate.rs

@@ -0,0 +1,235 @@
+//! PDF/A-2 6.2.5, the extended graphics state: device-dependent settings a conforming file may not
+//! rely on.
+//!
+//! - no transfer function: no `/TR` entry, and `/TR2` only as `/Default` (ISO 32000-1 10.4);
+//! - no `/HTP` (halftone phase) entry, a PDF 1.2 key ISO 32000-1 no longer defines;
+//! - halftones of type 1 or 5 only, without a `/HalftoneName` (ISO 32000-1 10.5.5); the halftones
+//!   a type 5 halftone holds for its colorants are checked the same way;
+//! - a halftone's `/TransferFunction` only where one is needed: a type 5 halftone's component for
+//!   a non-primary colorant has one, and no other halftone does. The primary colour components
+//!   are those of the standard device spaces: Gray; Red, Green and Blue; Cyan, Magenta, Yellow
+//!   and Black (ISO 32000-1 10.5.5.6; ISO 32000-2 10.6.5.6). The `Default` component is left as
+//!   it is (ISO 32000-1 Table 130);
+//! - a rendering intent (`/RI`) that is one of the four of ISO 32000-1 8.6.5.8, Table 70.
+//!
+//! Graphics state dictionaries are found as the `/ExtGState` entries of resource dictionaries
+//! (`/Resources` of pages, forms, Type 3 fonts, patterns and annotation appearances, and an
+//! interactive form's `/DR`), and as the `/ExtGState` of a shading pattern (ISO 32000-1 8.7.4.3,
+//! Table 76). They are looked for in what the document reaches from its trailer, following
+//! references, but not into private application data (`/PieceInfo`), so an object only that data
+//! refers to isn't read. A map shared by reference is read once.
+
+use std::collections::{BTreeSet, HashSet, VecDeque};
+
+use pdfcraft_cos::{Dict, Document, ObjRef, Object};
+
+/// How deep a direct object is followed: as deep as the parser nests them.
+const MAX_DEPTH: u8 = 128;
+/// The rendering intents of ISO 32000-1 Table 70.
+const INTENTS: [&[u8]; 4] = [b"AbsoluteColorimetric", b"RelativeColorimetric", b"Saturation", b"Perceptual"];
+/// The entries of a type 5 halftone that aren't colorant halftones.
+const HALFTONE_KEYS: [&[u8]; 3] = [b"Type", b"HalftoneType", b"HalftoneName"];
+/// The primary colour components of DeviceGray, DeviceRGB and DeviceCMYK, whose halftones take
+/// the graphics state's transfer function.
+const PRIMARY: [&[u8]; 8] = [b"Gray", b"Red", b"Green", b"Blue", b"Cyan", b"Magenta", b"Yellow", b"Black"];
+/// The entries that hold resource dictionaries.
+const RESOURCES: [&[u8]; 2] = [b"Resources", b"DR"];
+
+/// What the graphics states of a document break of 6.2.5.
+#[derive(Debug, Default, PartialEq, Eq)]
+pub(crate) struct Findings {
+    /// A graphics state has a `/TR` entry.
+    pub(crate) transfer: bool,
+    /// A graphics state has a `/TR2` other than `/Default`.
+    pub(crate) transfer2: bool,
+    /// A graphics state has an `/HTP`.
+    pub(crate) phase: bool,
+    /// Halftone types other than 1 and 5, in order.
+    pub(crate) halftone_types: BTreeSet<i64>,
+    /// A halftone's `/HalftoneType` is missing or isn't an integer.
+    pub(crate) untyped: bool,
+    /// A halftone has a `/HalftoneName`.
+    pub(crate) halftone_name: bool,
+    /// A halftone that may not have a `/TransferFunction` has one.
+    pub(crate) halftone_transfer: bool,
+    /// Non-primary colorants whose halftone has no `/TransferFunction`, in name order.
+    pub(crate) missing_transfer: BTreeSet<String>,
+    /// Rendering intents outside Table 70, in name order.
+    pub(crate) intents: BTreeSet<String>,
+    /// A rendering intent isn't a name.
+    pub(crate) intent_not_name: bool,
+}
+
+/// The 6.2.5 findings over what `doc` reaches from its trailer.
+pub(crate) fn check(doc: &Document) -> Findings {
+    scan(doc).findings
+}
+
+/// How many objects [`check`] reads.
+#[cfg(test)]
+pub(crate) fn reached(doc: &Document) -> usize {
+    scan(doc).reached.len()
+}
+
+fn scan(doc: &Document) -> Scan<'_> {
+    let mut scan = Scan { doc, read: HashSet::new(), reached: HashSet::new(), queue: VecDeque::new(), findings: Findings::default() };
+    scan.walk(&Object::Dict(doc.trailer().clone()), 0);
+    // References are followed from a queue, not by recursion: a chain of them can be as long as
+    // the file.
+    while let Some(r) = scan.queue.pop_front() {
+        let o = doc.get(r);
+        scan.walk(&o, 0);
+    }
+    scan
+}
+
+struct Scan<'a> {
+    doc: &'a Document,
+    /// Resource dictionaries, `/ExtGState` maps and graphics states read so far, by object number.
+    read: HashSet<u32>,
+    /// Object numbers reached so far, queued or walked. Both sets go by number, as
+    /// [`Document::get`] does: references differing only in generation reach the same object.
+    reached: HashSet<u32>,
+    queue: VecDeque<ObjRef>,
+    findings: Findings,
+}
+
+impl Scan<'_> {
+    fn walk(&mut self, o: &Object, depth: u8) {
+        if depth > MAX_DEPTH {
+            return;
+        }
+        let d = match o {
+            Object::Ref(r) => {
+                if self.reached.insert(r.num) {
+                    self.queue.push_back(*r);
+                }
+                return;
+            }
+            Object::Array(a) => {
+                for v in a {
+                    self.walk(v, depth.saturating_add(1));
+                }
+                return;
+            }
+            Object::Dict(d) => d,
+            Object::Stream(s) => &s.dict,
+            _ => return,
+        };
+        self.holder(d);
+        for (k, v) in d.iter() {
+            if k.as_slice() != b"PieceInfo" {
+                self.walk(v, depth.saturating_add(1));
+            }
+        }
+    }
+
+    /// Whether `o` is a reference read before; marks it read.
+    fn read_before(&mut self, o: &Object) -> bool {
+        matches!(o, Object::Ref(r) if !self.read.insert(r.num))
+    }
+
+    /// A dictionary that holds graphics states: through its resources, or as a shading pattern.
+    fn holder(&mut self, d: &Dict) {
+        for key in RESOURCES {
+            if let Some(resources) = d.get(key) {
+                self.resources(resources);
+            }
+        }
+        if d.get(b"PatternType").is_some()
+            && let Some(gs) = d.get(b"ExtGState")
+            && !self.read_before(gs)
+            && let Some(gs) = self.doc.resolve(gs).as_dict()
+        {
+            self.gstate(gs);
+        }
+    }
+
+    fn resources(&mut self, resources: &Object) {
+        if self.read_before(resources) {
+            return;
+        }
+        let resources = self.doc.resolve(resources);
+        let Some(states) = resources.as_dict().and_then(|r| r.get(b"ExtGState")) else { return };
+        if self.read_before(states) {
+            return;
+        }
+        let states = self.doc.resolve(states);
+        let Some(states) = states.as_dict() else { return };
+        for (_, gs) in states.iter() {
+            if !self.read_before(gs)
+                && let Some(gs) = self.doc.resolve(gs).as_dict()
+            {
+                self.gstate(gs);
+            }
+        }
+    }
+
+    /// `key` of `d`, resolved, unless it is missing or null (ISO 32000-1 7.3.9).
+    fn present(&self, d: &Dict, key: &[u8]) -> Option<std::sync::Arc<Object>> {
+        d.get(key).map(|v| self.doc.resolve(v)).filter(|v| !matches!(**v, Object::Null))
+    }
+
+    fn gstate(&mut self, gs: &Dict) {
+        if self.present(gs, b"TR").is_some() {
+            self.findings.transfer = true;
+        }
+        if self.present(gs, b"TR2").is_some_and(|f| f.as_name() != Some(b"Default")) {
+            self.findings.transfer2 = true;
+        }
+        if self.present(gs, b"HTP").is_some() {
+            self.findings.phase = true;
+        }
+        if let Some(ht) = self.present(gs, b"HT")
+            && let Some(ht) = ht.as_dict()
+        {
+            self.halftone(ht, None);
+        }
+        if let Some(ri) = self.present(gs, b"RI") {
+            match ri.as_name() {
+                Some(ri) if !INTENTS.contains(&ri) => {
+                    self.findings.intents.insert(String::from_utf8_lossy(ri).into_owned());
+                }
+                Some(_) => {}
+                None => self.findings.intent_not_name = true,
+            }
+        }
+    }
+
+    /// A halftone dictionary or stream: the graphics state's own (`colorant` is `None`), or the
+    /// one a type 5 halftone holds for `colorant`.
+    fn halftone(&mut self, ht: &Dict, colorant: Option<&[u8]>) {
+        // An integer (ISO 32000-1 Table 128), not a real of the same value.
+        let kind = self.present(ht, b"HalftoneType").and_then(|t| if let Object::Int(t) = *t { Some(t) } else { None });
+        match kind {
+            None => self.findings.untyped = true,
+            Some(1 | 5) => {}
+            Some(kind) => {
+                self.findings.halftone_types.insert(kind);
+            }
+        }
+        if self.present(ht, b"HalftoneName").is_some() {
+            self.findings.halftone_name = true;
+        }
+        let transfer = self.present(ht, b"TransferFunction").is_some();
+        match colorant {
+            Some(b"Default") => {}
+            Some(c) if !PRIMARY.contains(&c) => {
+                if !transfer {
+                    self.findings.missing_transfer.insert(String::from_utf8_lossy(c).into_owned());
+                }
+            }
+            _ => self.findings.halftone_transfer |= transfer,
+        }
+        if colorant.is_none() && kind == Some(5) {
+            for (k, v) in ht.iter() {
+                if HALFTONE_KEYS.contains(&k.as_slice()) {
+                    continue;
+                }
+                if let Some(component) = self.doc.resolve(v).as_dict() {
+                    self.halftone(component, Some(k));
+                }
+            }
+        }
+    }
+}

crates/preflight/src/lib.rs

@@ -21,6 +21,7 @@
 
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
 
+mod gstate;
 mod header;
 pub mod icc;
 mod limits;
@@ -183,6 +184,16 @@ pub const WORDINGS: &[&str] = &[
     "The spot colour {} of a DeviceN colour space isn't in its Colorants dictionary",
     "The document has additional actions (/AA)",
     "The document has document-level JavaScript",
+    "A graphics state has a transfer function (TR)",
+    "A graphics state has a transfer function (TR2) other than Default",
+    "A graphics state has a halftone phase (HTP)",
+    "A halftone has type {}: only types 1 and 5 are allowed",
+    "A halftone's HalftoneType is missing or isn't an integer",
+    "A halftone has a HalftoneName",
+    "A halftone has a transfer function, which only a non-primary colorant's halftone may have",
+    "The halftone for the colorant {} has no transfer function",
+    "A graphics state has the rendering intent {}, which isn't a standard one",
+    "A graphics state has a rendering intent that isn't a name",
     "The form asks viewers to make appearances (NeedAppearances)",
     // Pages, actions, annotations and fields.
     "Page {} has additional actions",
@@ -765,6 +776,38 @@ pub fn verify(doc: &Document, level: Level) -> Vec<Issue> {
     for name in spots.undefined {
         issue("6.2.4.4", "The spot colour {} of a DeviceN colour space isn't in its Colorants dictionary", Some(name), None, false);
     }
+    // 6.2.5: the extended graphics state.
+    let gs = gstate::check(doc);
+    if gs.transfer {
+        issue("6.2.5", "A graphics state has a transfer function (TR)", None, None, false);
+    }
+    if gs.transfer2 {
+        issue("6.2.5", "A graphics state has a transfer function (TR2) other than Default", None, None, false);
+    }
+    if gs.phase {
+        issue("6.2.5", "A graphics state has a halftone phase (HTP)", None, None, false);
+    }
+    for kind in gs.halftone_types {
+        issue("6.2.5", "A halftone has type {}: only types 1 and 5 are allowed", Some(kind.to_string()), None, false);
+    }
+    if gs.untyped {
+        issue("6.2.5", "A halftone's HalftoneType is missing or isn't an integer", None, None, false);
+    }
+    if gs.halftone_name {
+        issue("6.2.5", "A halftone has a HalftoneName", None, None, false);
+    }
+    if gs.halftone_transfer {
+        issue("6.2.5", "A halftone has a transfer function, which only a non-primary colorant's halftone may have", None, None, false);
+    }
+    for colorant in gs.missing_transfer {
+        issue("6.2.5", "The halftone for the colorant {} has no transfer function", Some(colorant), None, false);
+    }
+    for intent in gs.intents {
+        issue("6.2.5", "A graphics state has the rendering intent {}, which isn't a standard one", Some(intent), None, false);
+    }
+    if gs.intent_not_name {
+        issue("6.2.5", "A graphics state has a rendering intent that isn't a name", None, None, false);
+    }
     // One message per kind of problem is enough for repeated ones (as preflight summaries do).
     let mut out = out.into_inner();
     let mut seen = std::collections::HashSet::new();

crates/preflight/src/tests.rs

@@ -1589,3 +1589,91 @@ fn file_header_is_checked_and_rewritten() {
     let report = convert(&mut doc, Level::A2b).unwrap();
     assert!(!report.fixed.iter().any(|f| f == "Rewrote the file header"));
 }
+
+/// PDF/A-2 6.2.5: a graphics state has no transfer function, halftones of type 1 or 5 without a
+/// name, and a standard rendering intent, wherever it is kept.
+#[test]
+fn extended_graphics_states_are_checked() {
+    let gs = |states: &str| -> Vec<String> {
+        let page = format!("<< /Type /Page /Parent 2 0 R /Resources << /ExtGState << {states} >> >> >>");
+        let doc = build(
+            &[
+                "<< /Type /Catalog /Pages 2 0 R >>",
+                "<< /Type /Pages /Kids [3 0 R] /Count 1 /MediaBox [0 0 200 200] >>",
+                &page,
+                "<< /FunctionType 2 /Domain [0 1] /C0 [0] /C1 [1] /N 1 >>",
+                "<< /HalftoneType 1 /Frequency 60 /Angle 45 /SpotFunction /Round >>",
+                "<< /TR 4 0 R >>",
+                "<< /Type /Halftone /HalftoneType 6 /Width 2 /Height 2 /Length 4 >>\nstream\nabcd\nendstream",
+                "<< /Resources << /ExtGState << /X << /TR 4 0 R >> >> >> >>",
+            ],
+            "",
+        );
+        let issues = verify(&doc, Level::A2b).into_iter().filter(|i| i.clause == "6.2.5");
+        issues.inspect(|i| assert!(!i.fixable, "{}", i.message)).map(|i| i.message).collect()
+    };
+    let tr = "A graphics state has a transfer function (TR)";
+    let tr2 = "A graphics state has a transfer function (TR2) other than Default";
+    let name = "A halftone has a HalftoneName";
+    // What 6.2.5 allows.
+    assert!(gs("/A << /TR2 /Default /HT 5 0 R /RI /Perceptual >> /B << /HT /Default /RI /AbsoluteColorimetric >>").is_empty());
+    assert!(gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Cyan 5 0 R >> /RI /Saturation >> /B << /TR null >>").is_empty());
+    // Transfer functions.
+    assert_eq!(gs("/A << /TR 4 0 R >>"), [tr]);
+    assert_eq!(gs("/A << /TR /Identity >>"), [tr]);
+    assert_eq!(gs("/A 6 0 R"), [tr]);
+    assert_eq!(gs("/A << /TR2 4 0 R >>"), [tr2]);
+    assert_eq!(gs("/A << /TR2 /Identity >>"), [tr2]);
+    assert_eq!(gs("/A << /HTP [0 1] >>"), ["A graphics state has a halftone phase (HTP)"]);
+    // Halftones: the type, also of a type 5 halftone's colorants and of a stream, and the name.
+    assert_eq!(gs("/A << /HT << /HalftoneType 6 >> >>"), ["A halftone has type 6: only types 1 and 5 are allowed"]);
+    assert_eq!(gs("/A << /HT 7 0 R >>"), ["A halftone has type 6: only types 1 and 5 are allowed"]);
+    assert_eq!(
+        gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Magenta << /HalftoneType 10 >> >> >>"),
+        ["A halftone has type 10: only types 1 and 5 are allowed"]
+    );
+    assert_eq!(gs("/A << /HT << /HalftoneType 1 /HalftoneName (Screen) >> >>"), [name]);
+    assert_eq!(gs("/A << /HT << /HalftoneType 5 /Default << /HalftoneType 1 /HalftoneName (S) >> >> >>"), [name]);
+    // Rendering intents.
+    assert_eq!(gs("/A << /RI /Custom >>"), ["A graphics state has the rendering intent Custom, which isn't a standard one"]);
+    assert_eq!(gs("/A << /RI (Perceptual) >>"), ["A graphics state has a rendering intent that isn't a name"]);
+    // A halftone's type is required; a null name is no name.
+    let untyped = ["A halftone's HalftoneType is missing or isn't an integer"];
+    assert_eq!(gs("/A << /HT << /Frequency 60 >> >>"), untyped);
+    assert_eq!(gs("/A << /HT << /HalftoneType 1.0 >> >>"), untyped);
+    assert!(gs("/A << /HT << /HalftoneType 1 /HalftoneName null >> >>").is_empty());
+    // Transfer functions in halftones: only, and always, for a non-primary colorant.
+    let in_halftone = "A halftone has a transfer function, which only a non-primary colorant's halftone may have";
+    assert_eq!(gs("/A << /HT << /HalftoneType 1 /TransferFunction 4 0 R >> >>"), [in_halftone]);
+    assert_eq!(gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Cyan << /HalftoneType 1 /TransferFunction /Identity >> >> >>"), [in_halftone]);
+    // The primary components are those of DeviceGray, DeviceRGB and DeviceCMYK (ISO 32000-1 10.5.5.6).
+    assert_eq!(gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Gray << /HalftoneType 1 /TransferFunction /Identity >> >> >>"), [in_halftone]);
+    assert_eq!(
+        gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Spot 5 0 R /Red 5 0 R /Gray 5 0 R >> >>"),
+        ["The halftone for the colorant Spot has no transfer function"]
+    );
+    assert!(gs("/A << /HT << /HalftoneType 5 /Default 5 0 R /Black 5 0 R /Spot << /HalftoneType 1 /TransferFunction 4 0 R >> >> >>").is_empty());
+    // Private application data isn't graphics resources.
+    assert!(
+        gs("/A << /RI /Perceptual >> >> /PieceInfo << /App << /Private << /Resources << /ExtGState << /X << /TR 4 0 R >> >> >> >> >>").is_empty()
+    );
+    // Nor is an object (8) only private data refers to; one the page refers to is read.
+    assert!(gs("/A << /RI /Perceptual >> >> /PieceInfo << /App << /Private 8 0 R >> >> /Z <<").is_empty());
+    assert_eq!(gs("/A << /RI /Perceptual >> >> /Other 8 0 R /Z <<"), [tr]);
+    // A shading pattern holds one graphics state, not a dictionary of them.
+    let pattern = |gs: &str| format!("/A << /RI /Perceptual >> >> /Pattern << /P << /PatternType 2 /Shading << /ShadingType 2 >> /ExtGState {gs} >>");
+    assert_eq!(gs(&pattern("<< /TR 4 0 R >>")), [tr]);
+    assert!(gs(&pattern("<< /HT << /HalftoneType 1 >> >>")).is_empty());
+}
+
+/// From the review of the 6.2.5 check: references that differ only in generation reach the same
+/// object, which is read once.
+#[test]
+fn graphics_state_scan_reads_each_object_once_whatever_the_generation() {
+    let gens: String = (0..10).map(|g| format!("4 {g} R ")).collect();
+    let page = format!("<< /Type /Page /Parent 2 0 R /Same [{gens}] >>");
+    let doc =
+        build(&["<< /Type /Catalog /Pages 2 0 R >>", "<< /Type /Pages /Kids [3 0 R] /Count 1 /MediaBox [0 0 200 200] >>", &page, "[1 2 3]"], "");
+    // The catalog, the page tree, the page and object 4.
+    assert_eq!(gstate::reached(&doc), 4);
+}

parity/acrobat-features.toml

@@ -8017,8 +8017,8 @@ milestone = "M11"
 status = "partial"
 commands = ["standards.pdfa"]
 tools = ["pdfa_verify"]
-evidence = ["crates/preflight/src/tests.rs::verify_reports_what_breaks_pdfa", "crates/preflight/src/tests.rs::standards_identification_uses_namespace_not_prefix", "crates/preflight/src/tests.rs::convert_fixes_all_but_fonts", "crates/preflight/src/tests.rs::verify_reports_an_output_intent_that_does_not_match_device_colour", "crates/preflight/src/tests.rs::xmp_simple_values_have_their_lexical_forms", "crates/preflight/src/tests.rs::xmp_arrays_have_their_kind_and_item_types", "crates/preflight/src/tests.rs::xmp_structures_have_their_field_types", "crates/preflight/src/tests.rs::xmp_value_types_are_reported_by_verify", "crates/preflight/src/tests.rs::xmp_exif_schemas_have_their_value_types", "crates/preflight/src/tests.rs::xmp_exif_properties_are_known_by_namespace_uri", "crates/preflight/src/tests.rs::xmp_extension_schema_descriptions_are_complete", "crates/preflight/src/tests.rs::xmp_extension_findings_say_where_they_are", "crates/preflight/src/tests.rs::xmp_extension_naming_entries_are_not_empty", "crates/preflight/src/tests.rs::xmp_mistyped_properties_name_their_type", "crates/preflight/src/tests.rs::xmp_properties_are_known_by_namespace_uri_and_named_as_written", "crates/automation/tests/it/automation.rs::pdfa_through_tools", "crates/ui-egui/tests/it/compare.rs::pdfa_dialog_verifies_and_converts", "crates/preflight/src/tests.rs::implementation_limits_are_reported", "crates/preflight/src/tests.rs::implementation_limits_reach_the_trailer_split_content_deep_values_and_huge_boxes", "crates/preflight/src/tests.rs::implementation_limits_cover_reals_and_cids", "crates/preflight/src/tests.rs::separation_and_devicen_spaces_are_checked", "crates/preflight/src/tests.rs::separation_and_devicen_checks_follow_references_depth_and_nchannel", "crates/preflight/src/tests.rs::file_header_is_checked_and_rewritten"]
-notes = "PDF/A-2b/3b structural rules: the file header (6.1.2), identification, the value types of the predefined XMP schemas (6.6.2.3.1: dc, xmp, xmpRights, xmpMM, xmpBJ, xmpTPg, xmpDM, pdf, photoshop, crs, and tiff, exif and aux from the September 2005 XMP Specification, with their structures), XMP extension schema descriptions (6.6.2.3.3, after PDF Association TechNote 0009 section 4: required entries of the schema, property, value type and field descriptions, none of the naming entries empty, and the five required prefixes; that a property's custom value type has its own pdfaSchema:valueType description is not yet checked), encryption, output intent (present, and RGB/CMYK to match DeviceRGB/DeviceCMYK use), fonts embedded, annotations, actions, images, embedded files, the implementation limits of 6.1.13 (integers, reals, strings, names, CIDs and page boundaries, ISO 32000-1 Annex C), and Separation and DeviceN spaces (6.2.4.4: one definition per colorant name, spot colorants in /Colorants; a device alternate without a matching output intent is not yet reported). Not yet: content-stream operator checks, transparency details, PDF/A-1 and -4, a veraPDF comparison."
+evidence = ["crates/preflight/src/tests.rs::verify_reports_what_breaks_pdfa", "crates/preflight/src/tests.rs::standards_identification_uses_namespace_not_prefix", "crates/preflight/src/tests.rs::convert_fixes_all_but_fonts", "crates/preflight/src/tests.rs::verify_reports_an_output_intent_that_does_not_match_device_colour", "crates/preflight/src/tests.rs::xmp_simple_values_have_their_lexical_forms", "crates/preflight/src/tests.rs::xmp_arrays_have_their_kind_and_item_types", "crates/preflight/src/tests.rs::xmp_structures_have_their_field_types", "crates/preflight/src/tests.rs::xmp_value_types_are_reported_by_verify", "crates/preflight/src/tests.rs::xmp_exif_schemas_have_their_value_types", "crates/preflight/src/tests.rs::xmp_exif_properties_are_known_by_namespace_uri", "crates/preflight/src/tests.rs::xmp_extension_schema_descriptions_are_complete", "crates/preflight/src/tests.rs::xmp_extension_findings_say_where_they_are", "crates/preflight/src/tests.rs::xmp_extension_naming_entries_are_not_empty", "crates/preflight/src/tests.rs::xmp_mistyped_properties_name_their_type", "crates/preflight/src/tests.rs::xmp_properties_are_known_by_namespace_uri_and_named_as_written", "crates/automation/tests/it/automation.rs::pdfa_through_tools", "crates/ui-egui/tests/it/compare.rs::pdfa_dialog_verifies_and_converts", "crates/preflight/src/tests.rs::implementation_limits_are_reported", "crates/preflight/src/tests.rs::implementation_limits_reach_the_trailer_split_content_deep_values_and_huge_boxes", "crates/preflight/src/tests.rs::implementation_limits_cover_reals_and_cids", "crates/preflight/src/tests.rs::separation_and_devicen_spaces_are_checked", "crates/preflight/src/tests.rs::separation_and_devicen_checks_follow_references_depth_and_nchannel", "crates/preflight/src/tests.rs::file_header_is_checked_and_rewritten", "crates/preflight/src/tests.rs::extended_graphics_states_are_checked", "crates/preflight/src/tests.rs::graphics_state_scan_reads_each_object_once_whatever_the_generation"]
+notes = "PDF/A-2b/3b structural rules: the file header (6.1.2), identification, the value types of the predefined XMP schemas (6.6.2.3.1: dc, xmp, xmpRights, xmpMM, xmpBJ, xmpTPg, xmpDM, pdf, photoshop, crs, and tiff, exif and aux from the September 2005 XMP Specification, with their structures), XMP extension schema descriptions (6.6.2.3.3, after PDF Association TechNote 0009 section 4: required entries of the schema, property, value type and field descriptions, none of the naming entries empty, and the five required prefixes; that a property's custom value type has its own pdfaSchema:valueType description is not yet checked), encryption, output intent (present, and RGB/CMYK to match DeviceRGB/DeviceCMYK use), fonts embedded, graphics states (6.2.5: TR, TR2, HTP, halftone types, names and transfer functions with the primary components of ISO 32000-1 10.5.5.6, rendering intents), annotations, actions, images, embedded files, the implementation limits of 6.1.13 (integers, reals, strings, names, CIDs and page boundaries, ISO 32000-1 Annex C), and Separation and DeviceN spaces (6.2.4.4: one definition per colorant name, spot colorants in /Colorants; a device alternate without a matching output intent is not yet reported). Not yet: content-stream operator checks, transparency details, PDF/A-1 and -4, a veraPDF comparison."
 
 [[feature]]
 id = "optimize.pdfa-convert"