Add explicit FFmpeg trim command logging + duration verification

scripts/reframe.py

@@ -235,9 +235,20 @@ def main():
         if args.duration is not None:
             cmd += ["-t", str(args.duration)]
         cmd += ["-c", "copy", tmp.name]
-        subprocess.run(cmd, check=True, stderr=subprocess.DEVNULL)
+        print(f"🔧 TRIM CMD: {' '.join(cmd)}", file=sys.stderr)
+        result = subprocess.run(cmd, capture_output=True, text=True)
+        if result.returncode != 0:
+            print(f"❌ TRIM FAILED: {result.stderr[-500:]}", file=sys.stderr)
+            sys.exit(1)
         work_input = Path(tmp.name)
         print(f"✂  Trim → {work_input}")
+        # Verify trim output duration
+        verify = subprocess.run(
+            ["ffprobe", "-v", "error", "-show_entries", "format=duration",
+             "-of", "default=nw=1:nokey=1", str(work_input)],
+            capture_output=True, text=True
+        )
+        print(f"🔍 TRIMMED FILE DURATION: {verify.stdout.strip()}s (expected ~{args.duration}s)", file=sys.stderr)
 
     info = get_video_info(work_input)
     print(f"📹 Vhod: {info['width']}x{info['height']} @ {info['fps']:.2f}fps, {info['duration']:.1f}s")