| Feature | CS5.5 Capability | | :--- | :--- | | Native .MTS/.M2TS import | Yes (via Media Browser) | | 24p/25p/50p/60p support | 50p/60p only at reduced resolution in software mode | | 5.1 channel AC-3 audio | Converts to PCM on import (causes sync drift) | | GPU acceleration (CUDA/OpenCL) | No GPU decode for H.264/AVCHD | | 4:2:2 color (from Panasonic GH series) | Partial – requires interpretation as progressive |

To avoid long rendering times and ensure smooth playback, your sequence settings should match your footage:

Drag a clip from the Project panel onto the icon (at the bottom of the panel).

Adobe Premiere Pro CS5.5 can edit AVCHD, but not efficiently or reliably without intermediate codecs. The format’s long-GOP compression and CS5.5’s single-threaded software decoding make native editing a poor experience. By following the Media Browser ingest method, proxy transcoding to CineForm, and manually configuring sequence settings, you can achieve stable editing. However, for any professional or time-critical project, upgrading software is the definitive solution.