M17051 - Newspaper sequence - Results of 3DV/FTV Exploration

Experiments with depths and view synthesis.

October, 2009, Xi’an

Krzysztof KlimaszewskiOlgierd StankiewiczKrzysztof Wegner

team supervisor: Marek DomańskiChair of Multimedia Telecommunications and Microelectronics

Poznań University of Technology, Poland

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EE1

‘Newspaper’ sequence Recommended settings

Semiautomatic DERS5.0 + VSRS3.5 Half-pixel new manual information for key

frames Smoothing coefficient 1.0-4.0

Background – wrong depth

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new MDM file

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Frame 100 Frame 200

new MEM file

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Frame 100 Frame 200

Synthesis results - comparison

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Best results

Half-pixel precisionis 0.3dB betterthan pixel precisionwhich is 0.2dB betterthan quarter-pixel-precision

Results aresubjectively better

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Depth map obtained for

frame 0, 100, 200

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Conclussions

Semi-automatic DERS is better than automatic DERS

Still more key frames is needed to achieve better quality

EE 4

JMVM 5.0.6 GOP length was set to 16 Targeted bitrates 0.75, 1.5, 3, 6

Mbps for 2 view case QP – Quantization index for views QD – Quantization index for depth

maps

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Quantization parameters

Bitrate QP-QD pairs selected

750 kbps43-31, 37-36, 35-41, 38-34, 40-32, 39-33, 36-37,

35-40, 42-31, 44-30, 37-35

1.5 Mbps30-32, 35-26, 41-24, 28-44, 29-35, 31-30, 28-43,

28-42, 37-25, 40-24, 28-41

3 Mbps 29-21, 25-26, 23-34, 33-19, 24-28, 23-33, 30-20

6 Mbps 28-13, 20-20, 19-23

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Selected QP and QD indexes pairs which meet targeted bitrate

Results – 750 kbps

Bitrate[kbps]

QP QD

against uncompressed synthesis against original view

PSNR[dB]

PSNR (pspnr)

[dB]

PSPNR temporal

[dB]

PSPNR spatial

[dB]

PSNR[dB]

PSNR (pspnr)

[dB]

PSPNR temporal

[dB]

PSPNR spatial

[dB]

730 43 31 31.33 31.49 45.31 33.82 29.62 29.74 44.8 31.38

733 37 36 34.29 34.49 48.43 38.64 31.39 31.56 48.09 34.02

737 35 41 34.59 34.87 49.23 39.4 31.65 31.87 49.12 34.54

747 38 34 33.83 34.01 47.91 37.85 31.17 31.31 47.47 33.65

752 40 32 32.94 33.1 46.92 36.35 30.59 30.72 46.43 32.8

753 39 33 33.46 33.63 47.49 37.19 30.93 31.07 46.99 33.3

753 36 37 34.61 34.84 48.92 39.23 31.6 31.79 48.6 34.36

754 35 40 34.69 34.97 49.27 39.5 31.69 31.9 49.12 34.57

755 42 31 31.86 32.01 45.89 34.6 29.93 30.04 45.36 31.81

762 44 30 30.67 30.83 44.71 32.83 29.14 29.26 44.2 30.72

764 37 35 34.34 34.54 48.45 38.7 31.41 31.58 48.08 34.03

- the best result for given bitrate - the worst result for given bitrate

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Results - PSNR

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Results – PSNR without outer

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Results – PSPNR temporal

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Results – PSPNR spatial

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Results - summary

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0 1000 2000 3000 4000 5000 6000 7000

30

35

40

45

50

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Synthesized view quality (compared to uncompressed synthesis)

PSNRPSNR (pspnr)

PSPNR (temporal)

PSPNR (spatial)

bitrate [kbps]

Qu

alit

y [

dB]

Summary Quality of synthesized view depends more on quality of

compressed/decompressed image (QP parameter) than on quality of compressed/decompressed depth (QD).

The usual approach of choosing the minimal QP does not give the best results in some cases, but the differences of quality measures are neglible.

When quality of synthesized view is calculated with original view as a reference, no quality improvement is observed when increasing bitrate from 3 Mbps to 6Mbps in terms of PSNR, PSNR (pspnr) and PSPNR.

Quality of synthesized views (PSNR as well as PSPNR) increases, when measured with reference synthesized from uncompressed data in the similar way as for 2D sequences – approximately constant increase of quality for increase of bitrate by a factor of two.

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