better time formatting and ETA

compress_pngs.py

@@ -130,6 +130,14 @@ def format_size(size_bytes):
         size_bytes /= 1024.0
     return f"{size_bytes:.2f} TB"
 
+def format_time(seconds):
+    """Format time as HH:MM:SS:MsMs (hours:minutes:seconds:centiseconds)."""
+    hours = int(seconds // 3600)
+    minutes = int((seconds % 3600) // 60)
+    secs = int(seconds % 60)
+    centiseconds = int((seconds % 1) * 100)
+    return f"{hours:02d}:{minutes:02d}:{secs:02d}:{centiseconds:02d}"
+
 def main():
     input_dir = Path('input')
     output_dir = Path('output')
@@ -200,17 +208,19 @@ def main():
                 if processed == 1 or time_since_update >= 0.5:
                     rate = processed / elapsed if elapsed > 0 else 0
                     remaining = len(png_files) - processed
-                    eta = remaining / rate if rate > 0 else 0
+                    eta_seconds = remaining / rate if rate > 0 and remaining > 0 else 0
                     
                     total_savings = total_original_size - total_new_size
                     total_savings_pct = (total_savings / total_original_size * 100) if total_original_size > 0 else 0
                     
+                    eta_str = format_time(eta_seconds) if eta_seconds > 0 else "calculating..."
+                    elapsed_str = format_time(elapsed)
+                    
                     print(f"[{processed:5d}/{len(png_files)}] "
                           f"Compressed: {compressed} | Skipped: {skipped} | "
                           f"Speed: {rate:.1f} files/sec | "
-                          f"ETA: {eta:.1f}s | "
-                          f"Saved: {format_size(total_savings)} ({total_savings_pct:.1f}%) | "
-                          f"Elapsed: {elapsed:.1f}s", end='\r')
+                          f"Elapsed: {elapsed_str} | ETA: {eta_str} | "
+                          f"Saved: {format_size(total_savings)} ({total_savings_pct:.1f}%)", end='\r')
                     last_update_time = current_time
             else:
                 failed += 1
@@ -229,7 +239,7 @@ def main():
     if jpg_files:
         print(f"Ignored (JPG/JPEG): {len(jpg_files)} files")
     print(f"Failed: {failed} files")
-    print(f"Total time: {total_time:.2f} seconds")
+    print(f"Total time: {format_time(total_time)}")
     print(f"Average speed: {avg_rate:.2f} files/second")
     print(f"Original size: {format_size(total_original_size)}")
     print(f"Compressed size: {format_size(total_new_size)}")