Specifications

14 Issue Date: 2004/11/05 │ CONFIDENTIAL
CL765 │ Camera Application Processor
Datasheet │ Doc. #: CLQP-DS-743
1.4. EMBEDDED MEMORY
The CL765 embeds 256K bytes of internal SRAM that is accessible by Host CPU
(The CL765 embeds Strip Buffer also, but the Strip Buffer is not visible and
accessible for Host CPU. It is internally used only). The internal memory is used
mainly for JPEG encoding/decoding and buffer for OSD image. Host CPU can
access the whole space of the memory through Host interface protocol (refer to
4.2). The memory is conceptually partitioned into several dedicated spaces and
used. The partitioned spaces are as follows:
FIFO for Flow Control: flow-control scheme uses a part of internal memory
for transmitting data between Host CPU and the CL765. The internal memory
is used as a FIFO which is managed as a loop-buffer, i.e., for when
read/writer pointers reach to top of the FIFO, they are automatically set back
to bottom position. The size of FIFO buffer is programmable.
Video Buffer: the Video Buffer is the memory area assigned to video image
to be sent out through external visual devices interface. The size of Video
Buffer is programmable and generally same to the size of external visual
device, i.e., for LCD display, video buffer size is the same to the size of LCD
panel. The data format of image in Video Buffer is 4:2:2-YCbCr. Host CPU can
read YCbCr formatted image data from Video Buffer directly.
BMP Buffer: after JPEG2BMP Operation, additional to video image (that is
store into Video buffer after scaling), the decoded original (that means non-
scaled) image is also stored into internal memory that is called BMP Buffer.
Note) Refer to Bit[13] of JPEG2BMP in 4.4 Operation Mode Register
OSD Buffers: the CL765 provides two separated OSD images, OSD1 and
OSD2. The format of OSD is one of three types: 8bit-indexed, 4444-αRGB and
565-RGB.
Thumbnail Buffer: the RGB Thumbnail Buffer contains image for currently
being encoded image. The data format of thumbnail is 4:2:2-YCbCr. The size
of thumbnail is programmable (maximum size is 160 x 120).