AVCCAM and AVCHD Workflows

AVCCAM is the name of Panasonic Broadcast's professional video lineup employing the AVCHD format. All AVCCAM camcorders record to Secure Digital memory cards (SDHC) and have recording bitrates up-to 24 Mbit/s.

What is AVCHD?

AVCHD employs MPEG-4 AVC/H.264 (AVC) video coding. This codec is highly advanced, enabling very high quality images to be captured at around half the data rate of MPEG-2. AVCHD can record in various formats (1080i, 1080p and 720p) and at a range of frame rates. In terms of sound recording, AVCCAM records high quality Dolby AC3, and some AVCCAM cameras offer uncompressed audio recording as well.

SD Cards

Although SD cards are very widely available and extremely affordable, it is essential to select a compatible and reliable model. SD cards are classified according to their speed (Class 6 or preferably higher is recommended) and capacity - SDXC and SDHC allowing for the largest capacities. Those marketed as professional are likely to feature more thorough error correction technologies that keep the cards operating at peak efficiency while under heavy usage.

Long recording times

The newer AVCCAM cameras are compatible with SDXC, the newest SD memory card specification that supports memory capacities above 32GB and up-to 2TB. Those equipped with SDHC slots support a maximum size of 32Gb.

With two SD slots for continuous recording, SDXC models such as the AG-AC160a can record up to 12 hours on two 64GB SDXC cards in PH mode, with automatic clip spanning across the two cards. Moreover, its card slots are hot swappable so the camera can potentially run for days on end. And being without tape mechanisms or moving parts, there's no ageing heads so there's less potential for dirt or dust in the cameras. Tapeless camcorders therefore go longer between services - saving money and time.

Fast Transfers to Post

A producer shooting with a 64GB Class 10 card can transfer data into post at a speed of 24 Mb/s - eight times faster than realtime. While not as fast as P2, productions can still routinely save hours on ingest and digitizing with AVCCAM.

Here's a quick guide to ingesting content into:

Archive

As camera teams become accustomed to tapeless production and are free of the fear of running out of tape stock, there is often a dramatic surge in the amount of footage created. Whether a production unit needs to free up space to re-use a particular SD card or not, it is best practise to transfer the data to a separate, secure device and make copies of all content.

Because of this constant recycling of cards, productions need to adapt their way of working. Best practise includes:

  • Cards should be labelled for easy identification
  • When not in use, cards should be securely boxed
  • Where files span multiple cards, they must be transferred to archive consecutively to avoid incomplete clips
  • SD cards have a write protect switch on them; activate this feature before placing a card into any reading device. This indicates the card is ready for ingest and also prevents computers writing back to the card

Explaining Metadata

AVCHD clips are captured as files. They are appended with additional data that can speed up post production and allow for fast and accurate archiving. Meta tags are automatically created in-camera such as time, date and camera name.

Editors and media managers can then easily search for the clips they need. This functionality cuts editing time and for future programming, metadata avoids the pain of reviewing every file looking for the right clip.

Data Transfer

SD cards can simply be inserted into a laptop for fast transfer. Where multiple cards need to be transferred, a fast reader, such as Sonnet's SDXC UHS-I Pro Reader/Writer ExpressCard/34 or Panasonic's new USB 3.0 reader, can prove invaluable to load data fast onto a computer. Copies of the data can then be sent to external hard drives as a backup. The Sonnet portable storage devices, for example, incorporate fast interfaces with RAID technology for total security.

It may be tempting to drag and drop files from the camera onto the machine. However, the free AVCCAM Viewer software (bundled with the AVCCAM cameras) offers a number of advantages, not least of which (in the Windows version) is the ability to create and edit metadata - a huge benefit in post production. Furthermore, using the Viewer ensures that files are transferred without damaging the file structure of the card.

Avoiding common mistakes

AVCCAM is now supported by the majority of professional editing programmes. However, new edit systems, sometimes hurriedly released by manufacturers must be tested before clips are imported into their media bin. Third party software programmes can corrupt material or flash unexpected error messages - make sure your editor is compliant before working on the content. When content is mission-critical (when isn't it?) nothing should be left to chance. Test all procedures and systems in advance and plan how to ingest and edit in post before the shoot.

Action

As long as the individual steps have been thought through and tested, the process itself is now straight-forward. With a labelled memory card full of clips (complete with metadata), a device ready to store the data and the format tested to ensure that it is post-ready, the transfer can take place. The final stage is quickly to test and verify the media before it is used again.