at76c114 ATMEL Corporation, at76c114 Datasheet - Page 3

• Manufacturer Part Number: at76c114
• Description: Highperformance Digital/video Camera Processor At76c114 Summary
• Manufacturer: ATMEL Corporation

Description
5674BS–IMAGE–09/04
The AT76C114 is a highly integrated solution for dual-mode digital still-image and video
cameras. It combines a number of functions that are required in such devices, including
the following:
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The device is based on an ARM946E-S microprocessor whose function is to control
the entire system, to capture and play back audio, and to multiplex compressed
video and audio into a single bitstream that can be delivered to the main CPU. Most
computationally-intensive functions are implemented in hardware which can be
programmed according to user specifications, thus allowing the ARM
be free for other user-defined functions such as advanced image and multimedia
processing. The processor has 8 KB + 8 KB of internal instruction/data cache which
helps it to operate efficiently and use minimal DDR SDRAM bandwidth.
The device supports imager sizes of up to 16 megapixels. It accepts both Bayer
RGB and CCIR-656 interfaces, which cover all possible CCD and CMOS sensors. It
supports progressive as well as interlaced (up to 4 fields) imagers, including the
special readout modes of progressive VGA CCD imagers. The device also supports
a programmable delay on the external imager clock so that the highest quality
images can be captured.
The device has a high-performance still-image and video image processing block
that performs all the necessary functions to convert the image/video data to a format
that can be compressed in either JPEG or MPEG formats, as well as deliver image
data to the LCD controller for live view. This block performs gain control, color
recovery, Gamma correction, image enhancement, image correction, scaling, and
conversion to YC format. All those functions have been implemented in hardware to
achieve the required performance at very low power consumption figures. In
addition, there is a hardware block that collects statistics on the imager for auto-
exposure (AE) and auto-white balancing (AWB) algorithms. Those AE/AWB
algorithms are performed in the embedded ARM9 CPU to allow customization of the
application. The current architecture also has the appropriate interfaces as well as
sufficient performance to support a strobe-type flash light, as well as dark frame
subtraction for low-level light conditions.
The device has numerous display capabilities. It has an integrated video encoder
(double sampling) and two 10-bit video DACs running at up to 27 MHz to support
direct display to high-definition TVs and projectors. The device also has a 24-bit
RGB output to interface to flat-panel TVs (LCDs and Plasma) at different VESA
rates up to XGA (1024 x 768) resolution. It supports both square pixel and CCIR-
type formats and can display in NTSC or PAL modes with the same crystal. It also
has an integrated LCD controller which can interface directly to various LCDs. It
directly supports a variety of LCD panels from Epson, Casio, AU, and Toppoly
without the need for external ICs. Finally, it has a digital video output interface which
can supply composite, 8-bit YC (CCIR-656), 16-bit YC, RGB 565, or component
(Y/Pr/Pb) formats.
The device has a high-performance image scaler that can do up and down scaling
at floating point resolutions. In addition, the device supports hardware rotation, as
well as flipping and mirroring in both vertical and horizontal dimensions. It takes
approximately 120 ms to rotate a 2M image (1600 pixels) in any direction.
For video applications, a hardware video codec is included that supports MPEG-4
Simple Profile (encode and decode) and Advanced Simple Profile (encode only)
communication at up to 30 fps VGA resolution. The hardware video engine is a
pipelined architecture which is also flexible enough to support JPEG
compression/decompression, H.263, MPEG-2 encode(I/P frames) at 30 fps VGA,
and MPEG-1 encode/decode at 24 fps VGA (I frames only). The video codec can
also be used to record and play back video clips including those taken from other
AT76C114
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