Sony will release a new H.264-based codec this month to
enable its equipment cope with resolutions beyond HD, as well as higher frame
rates, while delivering higher quality pictures. It looks likely to be Sony’s
new core codec, so it could play an important role in future productions.
Once Sony’s new
PMW-F5 and PMW-F55 4K cameras start shipping
(sometime before BVE), users will be able to take advantage of the new, more
efficient, mid-range XAVC codec, which has been designed for 4K, and will offer
both intra frame and the more efficient Long GoP encoding. It will also allow
higher framerate recording at 1080p.
Sony is offering the F5 and F55 as multi-format cameras,
rather than just XAVC, “so that they would fit within the workflow people want
rather than restricting choice,” said Product Specialist Sebastian Leske.
The cameras will support four codecs: XAVC, for high frame
rates and 4K; MPEG2 at 50Mbps; MPEG4 SStP (Sony’s SR Master codec); and Raw 4K,
“by the switch of a button, depending on what job you want to do,” added
Olivier Bovis, Sony’s Head of AV Media.
XAVC is an extension of H.264 (AVC/MPEG4), using the highest
Level 5.2 of the standard, so it is very solid in terms of multi-generational
support, he explained.
However, as Sony already had HDCAM SR and Raw on offer, why
did it need yet another codec?
“The data rate from an F65 sensor can be as much as 35Gbps,
whereas the new SxS Pro+ cards can go up to 1.3Gbps. So, we still need
efficient compression to take all that data and package it in a manageable
way,” explained Strategic Marketing Manager Peter Sykes. Besides, MPEG2 simply
couldn’t cope with 4K, whereas XAVC is not only able to handle higher
resolution but higher frame rates too.
He doesn’t believe that Raw is suitable for every-day
production as it results in much higher data rates and can't be used as an
interchangeable format. Although Raw offers all the flexibility some
productions may need for high-end postproduction, it is inextricably linked to
the camera sensor, which complicates the workflow and makes it less suited to
productions that need to use a variety of different cameras.
Multiple formats
The F5 and F55 can record existing XDCAM HD formats at
50Mbps or 35Mbps, HDCAM SR (MPEG4 SStp) at up to 220Mbps or XAVC at 440Mbps.
For 4K work, you’ll be able to use intra-frame XAVC at 10-bit 4:2:2, which will
require 240Mbps at 24p or 600Mbps at 60p. For HD, it will record 10-bit 4:2:2,
at up to 60p, at 200Mbps. It can also deliver proxy 4:2:0 images at low bit
rates. Users will be able to choose between 8- and 10-bit recording for both
XAVC and MPEG2.
XAVC uses an MXF wrapper, as it is “industry standard and
well recognised,” said Sykes, and its implementation is identical to Sony’s
MPEG2 and MPEG4 SStP MXF OP-1a files.
“It is an enabling technology for a range of products that
will emerge from now on,” he added. “It’s a major part of our plan for our
acquisition products. XAVC will become the core codec for applications beyond
HD and for higher frame rates.”
“To drive beyond HD we had to develop XAVC,” agreed Leske.
“The design is future ready.” It will be able to do 4:4:4 (where it will be
able to go up to 1.2Gbps), although the F5 and F55 will use HDCAM SR for 4:4:4
work.
“To go beyond HD we needed a new codec, but it is also useful
for 1080 50p and 60p,” he added. “It uses a different mechanism to keep the
highest quality we can. It allocates more bits to the details (like hair) than
for flat areas (like a wall).”
It uses “a pre-coding mechanism to maximise the picture
quality,” expanded Sykes.
This uses bit estimation, the same procedure as used for DVD
authoring, which estimates what bit rate you need to get the highest quality.
If it doesn’t reach it, it does it again. Used as an intra-frame codec, XAVC
will do this for each frame, so they are all recorded to the highest possible
quality.
At present, H.264 codecs set the parameters for a recording
when you start recording, and stick to them, whereas XAVC can change them every
frame, so that when you shout ‘Action’, and there is suddenly lots of movement
and fine detail in the shot, you aren’t limited to parameters set when nothing
was happening.
Sykes believes that 4:2:2 10-bit XAVC at 100Mbps “will be a
good basis for broadcast infrastructure and relatively easy to handle.”
Open season
XAVC has been developed as an open format, providing a
license program for other manufacturers in the broadcast and production
industry to develop their own high quality and high frame rate products.
“It is a codec we are going to be using for lots of
different applications,” said Sykes. Sony developed the low power consumption
chipset used in the cameras. This not only does XAVC, but also processes MPEG2
– and because it is so fast can do both at once, so that the F55 can record
both 4K XAVC and XDCAM HD at 50Mbps simultaneously to its SxS Pro+ card.
Currently, it seems that the XAVC workflow will be supported
by such manufacturers as: Adobe (CS6 with Rovi Total Code Plug-in installed),
Apple [[
UPDATE -
Sony XAVC plug-in for Final Cut Pro X (version 10.0.8) now available to download]], Avid, Grass Valley, Quantel and Sony (Vegas Pro 12) for non-linear
editing; Assimilate, Codex, Colorfront, FilmLight, MTI and YoYotta for on-set
dailies; Assimilate, FilmLight and Quantel for colour grading; Rovi for
software codec management; and Matrox for a codec board.
The F5 is designed for HD on-board recording, requiring an
external recorder for 4K, whereas the F55 can record 4K internally as well as
HD.
On-board recording, in whatever format, will typically
require about 25 Watts, but adding the external Raw recorder will add an extra
22W. With the viewfinder attached the complete camera will require about 50W,
which is good for a 4K camera recording Raw.
For 16-bit 4K Raw, the system runs at data rates of up to
2.4Gbps for 60p, but this will only be possible with the new Sony AXS-R5
recorder, which fits to the camera body with no need for cabling. The cameras
will be able to record both Raw externally and XAVC internally at the same
time.
PMW-1000 Deck
To support XAVC (and SxS recording in general), Sony has
just announced the new PMW-1000 Memory Recording Deck. This is a half-rack
sized recorder, with two SxS memory card slots and VTR-like jog/shuttle
operations, that is suitable for both studio and Outside Broadcast use – and is
the first stand-alone recorder to handle the new codec.
Following the launch of the PMW-F5 and PMW-F55 CineAlta
cameras, “the PMW-1000 studio recording deck is the next natural step to bring
enhanced and easy workflow support,” said Fabien Pisano, Strategic Marketing
Manager, Sony Europe. “The versatility of the PMW-1000 in terms of interfaces,
coupled with linear-like operation and the ability to record the XAVC HD format
on SxS media, make it an ideal choice for broadcasters and production houses
looking for an affordable, quality production solution or for a smooth
transition from SD to HD.”
PMW-1000 users can select recording and playback formats
from HD (XAVC, MPEG HD422 and MPEG HD420 50/35/25Mbps) and SD (MPEG IMX
50/40/30Mbps and DVCAM 25Mbps) in a variety of frame rated. For anyone who
still has to do some work in SD (are there many?) the recorder is designed to
make the transition to HD easier, and can also do up-and-down conversion
from/to HD.
The PMW-1000 offers a wide range of AV and IT interfaces
including: HD-SDI, SD-SDI, HDMI, and composite outputs. An RS-422 interface
enables it to be used as a feeder for linear editing while a Gigabit Ethernet
(1000BASE-T) port allows for high-speed file transfer in network or non-linear
operations. The PMW-1000 also includes a HDMI output at the rear for easy
monitoring on HD displays.
A USB interface on the front panel enables easy
connection of external USB HDDs without a PC for the direct copying of clips.
It also boasts three-way power source selection. It can
operate on AC, DC or battery power, and so it can even be used on location. It
should be available in Europe from April.
Procam order
The 4K cameras seem to be attracting a lot of interest. One
of the UK’s biggest broadcast hire facilities,
Procam TV, has just spent
£500,000 on the PMW-F5 and PMW-F55. Procam believes it is the largest single
transaction of its kind in the broadcast hire industry.
It is getting its first instalment of 12 cameras this month,
and expects considerable demand from its current customers as well as attracting
new clients.
By David Fox