Tweaks (#24067)

* improve keyframes messages

* don't pad the labelmap with unknown

`load_labels()` prefilled 91 `unknown` entries before reading the label file, so any model with fewer than 91 classes kept that padding in `merged_labelmap` and `unknown` showed up as a selectable object type in the objects settings UI. The padding only existed so `RemoteObjectDetector.detect` could index the labelmap without a KeyError, and it didn't even cover the empty-file case or Frigate+, which never had a prefill. Both lookups now skip class ids the labelmap doesn't name and warn once per id.

web/public/locales/en/views/system.json

@@ -184,8 +184,10 @@
         "gap": "Keyframe gap (min / avg / max):",
         "segmentLength": "Recording segment length:",
         "ok": "Keyframes every ~{{seconds}}s, good for recording and playback.",
-        "warning": "Sparse or variable keyframes (longest gap ~{{seconds}}s), likely a smart codec (H.264+/H.265+), this is not recommended.",
-        "error": "Keyframe gap (~{{seconds}}s) exceeds the recording segment length ({{segmentTime}}s). Some segments may have no keyframe, which breaks playback. Disable the smart/+ codec on the camera or shorten its keyframe interval.",
+        "warningFixed": "Keyframes are evenly spaced but sparse (every ~{{seconds}}s). Recording still works, but live playback and seeking start more slowly. Set the camera's I-frame (keyframe) interval to match its frame rate.",
+        "warningVariable": "Keyframe spacing is inconsistent ({{minSeconds}}s to {{maxSeconds}}s), which usually means a smart codec (H.264+/H.265+) is enabled. This is not recommended.",
+        "errorFixed": "Keyframes every ~{{seconds}}s is longer than the recording segment length ({{segmentTime}}s), so some segments have no keyframe and will not play back. Shorten the camera's I-frame (keyframe) interval to match its frame rate.",
+        "errorVariable": "Keyframe gaps reach ~{{seconds}}s, longer than the recording segment length ({{segmentTime}}s). Some segments will have no keyframe, which breaks playback. Disable the smart/+ codec on the camera or shorten its keyframe interval.",
         "unknown": "Couldn't determine keyframe spacing.",
         "recordDisabled": "Recording is disabled for this camera."
       }

web/src/components/overlay/KeyframeAnalysisSection.tsx

@@ -89,17 +89,29 @@ export default function KeyframeAnalysisSection({
       case "warning":
         summary = (
           <Row icon="warning">
-            {t("cameras.info.keyframes.warning", { seconds: analysis.max_gap })}
+            {analysis.pattern === "fixed"
+              ? t("cameras.info.keyframes.warningFixed", {
+                  seconds: analysis.mean_gap,
+                })
+              : t("cameras.info.keyframes.warningVariable", {
+                  minSeconds: analysis.min_gap,
+                  maxSeconds: analysis.max_gap,
+                })}
           </Row>
         );
         break;
       case "error":
         summary = (
           <Row icon="error">
-            {t("cameras.info.keyframes.error", {
-              seconds: analysis.max_gap,
-              segmentTime: analysis.segment_time,
-            })}
+            {analysis.pattern === "fixed"
+              ? t("cameras.info.keyframes.errorFixed", {
+                  seconds: analysis.mean_gap,
+                  segmentTime: analysis.segment_time,
+                })
+              : t("cameras.info.keyframes.errorVariable", {
+                  seconds: analysis.max_gap,
+                  segmentTime: analysis.segment_time,
+                })}
           </Row>
         );
         break;

web/src/types/stats.ts

@@ -161,6 +161,8 @@ export type KeyframeSeverity =
   | "unknown"
   | "record_disabled";
 
+export type KeyframeGapPattern = "fixed" | "variable";
+
 export type KeyframeAnalysis = {
   severity: KeyframeSeverity;
   stream_index?: number;
@@ -168,6 +170,7 @@ export type KeyframeAnalysis = {
   max_gap?: number | null;
   mean_gap?: number | null;
   min_gap?: number | null;
+  pattern?: KeyframeGapPattern | null;
   duration_observed?: number | null;
   segment_time?: number;
   thresholds?: { warning: number; error: number };