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NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
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Revision V1.30
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bit-stream
fixed size
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JPEG Engine
JPEG Engine
ENC_MODE=10
JPEG Engine
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Dual buffer
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JPEG Engine
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Single mode
Continue mode
Figure 5.29-5 Single mode and continue mode
JPEG Decode
5.29.5.3
The JPEG decoding operation is very similar to the feedback loop of the JPEG encoding. After
operation is triggered, the JPEG bit-stream is fetched from frame memory and processed by the
variable-length decoder (VLD). The decoded data are parsed, inverse zig-zag scanned (IZZ), inverse
quantization (IQ) and inverse DCT (IDCT). An offset value is added to the output data of IDCT to
become the reconstruction picture.
The JPEG decoder also integrates a post-processing unit that can apply some post-processing to the
decoded image. It can scale-down the image in horizontal and vertical directions.
JPEG Decode Operation
5.29.5.4
The JPEG decoder can decode the JPEG bit-stream that is baseline JPEG format. When the
programmer want to decode JPEG bit-stream, he just needs to specify the starting address of the
JPEG bit-stream in frame memory by registers JIOADDR0 or JIOADDR1 and set JPEG decode mode
by register bit ENC_DEC (JMCR[7]), and then trigger the JPEG engine. When the decode operation is