Panasonic BB-HCM580A, Service Manual

Page: 12 / 93

12
BB-HCM580A
4.3. Image Compression Block
• Image compression (JPEG/MPEG-4 encode) function, memory control unit (MCU), ETHERNET MAC, and SD card controller
are built into IC102.
• Picture data input from the camera block is captured in SDRAM (1).
• Captured image data is input to the ZOM block, where the scaling of the image size is done, (an image size of 640 x 480, 320 x
240, or 192 x 177 is generated from the one with the size of 1280 x 1024, or an image size of 320 x 240 or 192 x 177 from the
one with the size of 640 x 480), and is stored in SDRAM again (2).
• The scaled image data is input to the JPEG/MPEG-4 encode section of IC102, and the image is compressed. The compressed
image data is stored in SDRAM again (3).
• After CPU processed the compressed image data for a communication protocol, the data is forwarded to the network via ETH-
ERNET MAC and ETHERNET PHY. And the image data of post-compression is processed for a file and is recorded on the SD
card.
• As for the video output, the captured image data is scaled to a size of NTSC or PAL at the ZOM block, and then it is output from
VIDEO OUT and DAC sections as an analog video signal.
• This analog video signal is amplified by the video amplifier (IC109) and output from CN604 on the IO board with the output
impedance of 75 Ω .