STV0684 datasheet(21/49 Pages) STMICROELECTRONICS

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STV0684

Functional Description

3.9

JPEG CODEC

Description

The STV0684 features a compression and a decompression engine that is used for both Still

pictures and video clips. The hardware CODEC ensures a fast reaction time of the system to

encode and decode data. This is particularly important to minimize the shutter to shutter time and

the ability to rapidly display images on a local display or the TV set.

Compression engine The compression engine uses Baseline Sequential JPEG techniques to

compress a digital 656 video stream (at up to 12MPixels/s), down to bandwidth that can be

transmitted over the USB interface or to a mass storage media, typically 500-900Kbytes/s. It outputs

a JPEG data stream with the headers required by standard decoders.

Decompression engine The JPEG decoder block reads the compressed data from the DMA fifo,

parses the header and writes back decompressed data back to DMA fifo. This data is organized in

8x8 blocks of the different color components. This data can be converted to raster scan format to be

read by the display controller for display on a LCD or TV.

STV0684 数据表(PDF) 21 Page - STMicroelectronics