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coding pass. This distortion reduction estimate is used to determine the codeblock
bitstream truncation in Tier 2 of the codec, which directly translates to the quanti-
zation step size. The rounding errors of the transform have a very limited influ-
ence on the distortion estimates, especially for the coding passes performed on the
higher bit-planes. As a result, quantization of the wavelet coefficients in succes-
sive encoding cycles will be almost identical, causing little additional quality loss.
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65000000
85000000
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Bit-rate (bits/s)
H.264/AVC Intra
Bit-rate (bits/s)
Motion JPEG 2000
H.264/AVC Intra
Motion JPEG 2000 Field
Motion JPEG 2000 Frame
720p50, 2 nd encoding-decoding cycle
1080i25, 2 nd encoding-decoding cycle
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25000000
45000000
65000000
85000000
105000000
25000000
45000000
65000000
85000000
105000000
Bit-rate (bits/s)
H.264/AVC Intra
Bit-rate (bits/s)
Motion JPEG 2000
H.264/AVC Intra
Motion JPEG 2000 Field
Motion JPEG 2000 Frame
720p50, 4 th encoding-decoding cycle
1080i25, 4 th encoding-decoding cycle
Fig. 10 Recompression loss for ParkJoy sequence
To conclude this section, a short qualitative evaluation of the functionality and
the complexity of both coding standards will be presented. Motion JPEG 2000 in-
herently supports resolution and quality scalability. To obtain similar functionality,
H.264/AVC's scalable extension [8, 26] must be used, which requires a different
encoder and decoder. Additionally, Motion JPEG 2000 supports region-of-interest
(ROI) coding with near-pixel granularity by using the max-shift method [20, 21].
ROI can also be supported in AVC by using slice groups, but the granularity is lim-
ited to a single macroblock. (Motion) JPEG 2000 was also designed to deliver
state-of-the-art lossless compression performance. H.264/AVC can also support
lossless compression but the performance of this mode is sub-optimal, as it solely
relies on crude block-based intra-prediction for decorrelation.
Concerning computational complexity, it is difficult to draw clear conclusions
as this is highly implementation and platform dependant. Certain is that Motion
JPEG 2000 has similar complexity for encoding and decoding, while for
H.264/AVC, the encoder is much more complex than the decoder. In general,
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