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PRELIMINARY
FIMV-MFC V1.0
MULTI-FORMAT
VIDEO
CODEC
2
1-37
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Overlap-smoothing/Deblocking Filter
Overview
Deblocking filter removes blocking artifacts resulted from quantization, different motion vectors. The filter
processing is applied in both decoder and encoder. FIMV-MFC V1.0 deblocking filter supports
H.264/H.263/MPEG4. For H.264 and H263, the deblocking filter operates within coding loop. Filtered frames are
used as reference frames for motion compensation of subsequent coded frames. But for MPEG4, the deblocking
filter operates outside coding loop for only display.
The basic coding structure of H.264 is shown in Figure 21.28.
Figure 21.28. H.264 deblocking filter data flow
Processing modes
FIMV-MFC V1.0 supports 2 operating modes for each standard regarding to whether the filtering process is
applied to the reconstructed image in the macroblock pipeline or not.
On-the-fly mode
In the on-the-fly mode, the macroblock output from the reconstruction is immediately filtered without saving the
entire reconstructed output to external SDRAM. The DMA controller transfer only part of the reconstructed
macroblock that cannot be filtered due to absence of reconstruction pixel data of neighboring macroblock. This