Store seven eye numbers per face rather than three

Per eye P(open), the pixels across its box and the sharpness of the
patch; and P(sunglasses). The verdict — open, closed, sunglasses,
unclear — stays a rule in dr_face::eyes so the floors can move without
re-measuring twenty thousand faces. Shards carry the same seven, and a
peer's shard from before any of them is still read.

core/dr-catalog/src/schema.rs

@@ -163,11 +163,19 @@ pub fn migrate(conn: &Connection) -> Result<i64, CatalogError> {
     Ok(from)
 }
 
-/// The three columns V16 adds to `faces`, in the order the readers name them.
+/// The seven columns V16 adds to `faces`, in the order the readers name them.
 ///
 /// Named once because three places have to agree on them: this migration,
 /// [`for_attached`], and the face shard's own catch-up (`face_shard`).
-pub const EYE_COLUMNS: [&str; 3] = ["eye_right", "eye_left", "sunglasses"];
+pub const EYE_COLUMNS: [&str; 7] = [
+    "eye_right",
+    "eye_right_px",
+    "eye_right_sharp",
+    "eye_left",
+    "eye_left_px",
+    "eye_left_sharp",
+    "sunglasses",
+];
 
 /// Recompute columns a migration added, for rows that predate it.
 ///
@@ -328,7 +336,11 @@ pub fn for_attached(schema_name: &str) -> String {
          ALTER TABLE {schema_name}.faces ADD COLUMN crop BLOB;\n\
          ALTER TABLE {schema_name}.faces ADD COLUMN quality REAL;\n\
          ALTER TABLE {schema_name}.faces ADD COLUMN eye_right REAL;\n\
+         ALTER TABLE {schema_name}.faces ADD COLUMN eye_right_px REAL;\n\
+         ALTER TABLE {schema_name}.faces ADD COLUMN eye_right_sharp REAL;\n\
          ALTER TABLE {schema_name}.faces ADD COLUMN eye_left REAL;\n\
+         ALTER TABLE {schema_name}.faces ADD COLUMN eye_left_px REAL;\n\
+         ALTER TABLE {schema_name}.faces ADD COLUMN eye_left_sharp REAL;\n\
          ALTER TABLE {schema_name}.faces ADD COLUMN sunglasses REAL;",
         rewrite_for_attached(V1, schema_name),
         rewrite_for_attached(V6, schema_name),
@@ -734,16 +746,19 @@ CREATE TABLE IF NOT EXISTS xmp_conflicts (
 
 // V16 -- TRACES: FR-CULL-13
 //
-// What each face's eyes are doing: P(open) for the subject's right and left
-// eye, and P(sunglasses) for the head, each a sigmoid from a classifier run
-// over the aligned crop at indexing time (dr_face::classify). Three numbers
-// rather than a verdict, because the verdict is a rule with thresholds in it
-// (dr_face::eyes::EyeReading::state) and a rule belongs in code that can be
-// changed, not in rows that would have to be re-measured.
+// What each face's eyes are doing: for each eye P(open), the source pixels
+// across its box and the sharpness of the patch the classifier saw; and
+// P(sunglasses) for the head. Seven numbers rather than a verdict, because
+// the verdict is a rule with thresholds in it (dr_face::eyes::EyeReading::
+// state) and a rule belongs in code that can be changed, not in rows that
+// would have to be re-measured.
 //
-// Sunglasses are a column of their own and not folded into the eye numbers,
-// because the eye classifier answers confidently over dark glass and its
-// answer means nothing there. A filter for "eyes open" reads all three.
+// The pixels and the sharpness are what stop a smear reading as a blink: an
+// eye too small or too soft to read is not asked, and a face with no
+// readable eye is "unclear", which no filter drops. Sunglasses are a column
+// of their own for the same kind of reason — the eye classifier answers
+// confidently over dark glass, and its answer means nothing there. A filter
+// for "eyes open" reads all seven.
 //
 // NULL means "never measured" -- a face indexed before this version, or on a
 // device without the eye models -- and a NULL is left alone by every filter