Vendor the command set the menu and shell depend on

bin/blob-capture-webcam-list

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# blob:summary=List webcam devices that support video capture
+# blob:hidden=true
+
+capture_capable() {
+  local device="$1"
+
+  v4l2-ctl --device "$device" --info 2>/dev/null | awk '
+    /^[[:space:]]*Device Caps[[:space:]]*:/ { inspect = 1; next }
+    inspect && /^[[:space:]]*Video Capture/ { found = 1 }
+    END { exit !found }
+  '
+}
+
+name=""
+emitted=0
+
+while IFS= read -r line; do
+  if [[ -n $line && $line != [[:space:]]* ]]; then
+    name="$line"
+    emitted=0
+  elif (( ! emitted )); then
+    device="${line#"${line%%[![:space:]]*}"}"
+
+    if [[ $device == /dev/video* ]] && capture_capable "$device"; then
+      emitted=1
+      printf '%s  %s\n' "$device" "$name"
+    fi
+  fi
+done < <(v4l2-ctl --list-devices 2>/dev/null)
+
+exit 0