Copyright © 2003 Texas Instruments. All rights reserved. DSP C5000 Chapter 18 Image Compression and Hardware Extensions.

Copyright © 2003 Texas Instruments. All rights reserved.

DSP C5000DSP C5000

Chapter 18Chapter 18

Image Compression andImage Compression and

Hardware ExtensionsHardware Extensions


ESIEE, Slide 2

Image CompressionImage Compression

Discrete Cosine Transform (DCT) Discrete Cosine Transform (DCT) based compressionbased compression Still image: JPEG.Still image: JPEG.

Remove spatial redundancyRemove spatial redundancy

Video: H263, MPEG4.Video: H263, MPEG4. Remove spatial redundancyRemove spatial redundancy Remove temporal redundancyRemove temporal redundancy


ESIEE, Slide 3

JPEG EncoderJPEG Encoder Image is split into 8x8 pixel block that are Image is split into 8x8 pixel block that are

processed .processed .

DCT is applied on input block to obtain the DCT is applied on input block to obtain the frequency data.frequency data.

Values are read from low to high frequency Values are read from low to high frequency thanks to zig-zag addressing.thanks to zig-zag addressing.

Data are then quantized according to a quality Data are then quantized according to a quality factor.factor.

This output is then run length and entropy This output is then run length and entropy coded.coded.


ESIEE, Slide 4

JPEG DecoderJPEG Decoder

Data are entropy decoded.Data are entropy decoded. They are dequantized according to a quality They are dequantized according to a quality

factor.factor. Zig-zag addressing to re-order the data pixel by Zig-zag addressing to re-order the data pixel by

pixel.pixel. Inverse DCT to recover spatial data.Inverse DCT to recover spatial data.


ESIEE, Slide 5

H263 and MPEG4 encoderH263 and MPEG4 encoder Same basic building blocksSame basic building blocks

Hardware accelerator provided by C5509/10Hardware accelerator provided by C5509/10


ESIEE, Slide 6

H263 and MPEG4 DecoderH263 and MPEG4 Decoder Same basic building blocksSame basic building blocks

Hardware accelerator provided by C5509/10Hardware accelerator provided by C5509/10


ESIEE, Slide 7

Hardware ExtensionsHardware Extensions

‘‘C5509 and ‘C5510 provide H/W C5509 and ‘C5510 provide H/W extensions for video compression:extensions for video compression: DCT, IDCTDCT, IDCT Pixel interpolationPixel interpolation Motion estimationMotion estimation

Hardware extensions are embedded co-Hardware extensions are embedded co-processors:processors: Access to ACx, DARAM and SARAM.Access to ACx, DARAM and SARAM. Provide video codec with less than half of Provide video codec with less than half of

the processing bandwidth.the processing bandwidth.


ESIEE, Slide 8

DCT H/W Extension 1 of 5DCT H/W Extension 1 of 5

Allows 4x4 and 8x8 pixels DCT/IDCT Allows 4x4 and 8x8 pixels DCT/IDCT computation:computation: 2D DCT2D DCT

2D IDCT 2D IDCT

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ESIEE, Slide 9


Basic steps to complete a 2D Basic steps to complete a 2D DCT/IDCT:DCT/IDCT: Input Data: macro block (4x4 or 8x8) is Input Data: macro block (4x4 or 8x8) is

read in (DCT). DCT coefficient matrix is read in (DCT). DCT coefficient matrix is read in (IDCT).read in (IDCT).

Column DCT/IDCT process: output to Column DCT/IDCT process: output to temporary registers that will be transposed temporary registers that will be transposed for Row processing.for Row processing.

Row DCT/IDCT process: data read from Row DCT/IDCT process: data read from temporary register which are processed temporary register which are processed column by column.column by column.


ESIEE, Slide 10



ESIEE, Slide 11


Instruction set:Instruction set: Load+computation+transfer to accumulator:Load+computation+transfer to accumulator:

ACy=copr(k8,ACx,Xmem,Ymem)ACy=copr(k8,ACx,Xmem,Ymem) Computation+transfer to accumulator+memory Computation+transfer to accumulator+memory

write:write:

ACy=copr(k8,ACx,ACy),Lmem=AczACy=copr(k8,ACx,ACy),Lmem=Acz Special instructions: Special instructions:

ACy=copr(k8,ACx,ACy)ACy=copr(k8,ACx,ACy) Refer to Refer to application noteapplication note for details and listings for details and listings

of macros realizing complete 8x8 DCT/IDCT.of macros realizing complete 8x8 DCT/IDCT.


ESIEE, Slide 12


H/W extensions can be used through C-H/W extensions can be used through C-callable functions provided by callable functions provided by IMLIBIMLIB


ESIEE, Slide 13

DebugDebug•To look at the internal register of the hardware extension …To look at the internal register of the hardware extension …

DCT and IDCT DCT and IDCT

Hardware accelerator Hardware accelerator

registersregisters


ESIEE, Slide 14

Tutorial DCT/IDCT with IMLIBTutorial DCT/IDCT with IMLIB

Describe step by step how to use H/W Describe step by step how to use H/W extensions with IMLIB.extensions with IMLIB.

Requires installation of Requires installation of IMLIBIMLIB before before continuing.continuing.

Requires special memory configuration Requires special memory configuration to obtain optimum performance.to obtain optimum performance.

CCS allows display of image contained CCS allows display of image contained in DSP memory.in DSP memory.


ESIEE, Slide 15

Memory ConfigurationMemory Configuration

dct.cmddct.cmd

hwdct.cdbhwdct.cdb


ESIEE, Slide 16

Display Input Image 1 of 2Display Input Image 1 of 2

Load hwdct.pjtLoad hwdct.pjt Build and load applicationBuild and load application Input image is « goldhill » 128x128 Input image is « goldhill » 128x128

which is included by the header file which is included by the header file ((#include «imagesample.h»#include «imagesample.h») at the ) at the address address goldhillgoldhill

To have the internal memory initialized To have the internal memory initialized use use Debug>go to mainDebug>go to main command. command.

You are now ready to display the input You are now ready to display the input image using image using view>Graph>imageview>Graph>image


ESIEE, Slide 17

Display Input Image 2 of 2Display Input Image 2 of 2


ESIEE, Slide 18

In place DCT ComputationIn place DCT Computation


ESIEE, Slide 19

Actual Actual dct.cdct.c Program Program


ESIEE, Slide 20

Output Display and InitializationOutput Display and Initialization


ESIEE, Slide 21

Output Buffer UpdateOutput Buffer Update


ESIEE, Slide 22

ReferencesReferences JPEG for digital panel JPEG for digital panel ((SPRA664SPRA664))

TMS320C55x Hardware extensions for TMS320C55x Hardware extensions for image/video applications - Programmer’s image/video applications - Programmer’s reference reference ((SPRU098SPRU098))

TMS320C55x image/video processing TMS320C55x image/video processing library programmer’s reference library programmer’s reference ((SPRU037SPRU037))

Copyright © 2003 Texas Instruments. All rights reserved. DSP C5000 Chapter 18 Image Compression and Hardware Extensions.

Documents

hardware extensions

c550910 slide

imlibimlib slide

texas instruments

idct dct

d idct slide

dct hw extension

hardware extension dct