Owner`s manual

nanoFlash FAQs
10-Apr-10 ©Convergent Design, Inc. Page 4 of 42
Your camera’s recording subsystem has two major components: the CODEC and the
storage device. The CODEC compresses the video from about 1,200 Mbps
(uncompressed HD) to a more manageable 18 to 280 Mbps. The storage device is
typically a tape, optical disk, or possibly a memory card. Compressed video, along with
audio and timecode, is stored on these media for playback or transfer to a NLE.
The CODEC and storage medium are both significant in determining your video quality.
In general, the higher bit-rate produces better the video quality. However, most storage
media severely restrict the possible data-rates. Mini-DV tape (used in HDV cameras), for
example, has a fixed read/write bandwidth about 25 Mbps; SDHC memory cards are
limited to about 45 Mbps. So, the ultimate data-rate from the CODEC must be restricted
to match the performance of the storage medium.
The level of sophistication and implementation of the CODEC play a major role as well.
I-Frame only CODECs, in general, require two to three times the bit-rate to equal the
quality of the more sophisticated Long-GOP CODECs. (100 Mbps I-Frame is roughly
equivalent to 35 Mbps Long-GOP in overall quality). Most CODECs, (HDV, DVCPro HD,
XDCAM EX, and even HDCAM) also reduce the potential quality through color-sample
decimation (4:2:2 → 4:2:0 or 3:1:1) and/or by horizontally sub-sampling (1920 → 1440 or
1920 → 1280).
The Solution: nanoFlash – High Bit-Rate, Full-Raster, 4:2:2
The nanoFlash overcomes these quality-robbing restrictions in your camera. You connect
to the HD/SD-SDI or HDMI camera output (in live mode) to send “never-compressed”
video directly from the CCD/CMOS sensor to the high-quality CODEC and then to the
high-speed digital storage (CompactFlash cards) in the nanoFlash.
Since nanoFlash records on CompactFlash solid-state memory, (as opposed to tape,
optical disk or SDHC cards) the bit-rate can be substantially increased over your built-in
recorder. For example, Transcend now offers a 64GB 400X Compact Flash cards which
support data-rates up to 220 Mbps for approx $200.
nanoFlash features a sophisticated high-quality Sony MPEG2 CODEC with data-rates up
to 180 Mbps in Long-GOP mode (I,P,B Frames), and up to 280 Mbps in I-Frame-only
mode. The CODEC compresses the video without reducing the color sampling (full 4:2:2)
and without sub-sampling the horizontal data (full 1920).