qccvidmotionestimationfullsearch.3

QccPack-0.54-1 released (2007-04-30) is being developed and tested on Fedora Core Linux. QccPack pro

.TH QCCVIDMOTIONESTIMATIONFULLSEARCH 3 "QCCPACK" ""
.SH NAME
QccVIDMotionEstimationMAE,
QccVIDMotionEstimationExtractBlock,
QccVIDMotionEstimationInsertBlock,
QccVIDMotionEstimationFullSearch,
QccVIDMotionEstimationCalcReferenceFrameSize,
QccVIDMotionEstimationCreateReferenceFrame,
QccVIDMotionEstimationCreateCompensatedFrame \- routines for
full-search, block-based motion estimation and compensation
.SH SYNOPSIS
.B #include "libQccPack.h"
.sp
.BI "double QccVIDMotionEstimationMAE(QccMatrix " current_block ", QccMatrix " reference_block ", int " block_size );
.br
.sp
.BI "int QccVIDMotionEstimationExtractBlock(const QccIMGImageComponent *" image ", double " row ", double " col ", QccMatrix " block ", int " block_size ", int " subpixel_accuracy );
.br
.sp
.BI "int QccVIDMotionEstimationInsertBlock(QccIMGImageComponent *" image ", double " row ", double " col ", const QccMatrix " block ", int " block_size ", int " subpixel_accuracy );
.br
.sp
.BI "int QccVIDMotionEstimationFullSearch(const QccIMGImageComponent *" current_frame ", const QccIMGImageComponent *" reference_frame ", QccIMGImageComponent *" motion_vectors_horizontal ", QccIMGImageComponent *" motion_vectors_vertical ", int " block_size ", int " window_size ", int " subpixel_accuracy );
.br
.sp
.BI "int QccVIDMotionEstimationCalcReferenceFrameSize(int " num_rows ", int " num_cols ", int *" reference_num_rows ", int *" reference_num_cols ", int " subpixel_accuracy );
.br
.sp
.BI "int QccVIDMotionEstimationCreateReferenceFrame(const QccIMGImageComponent *" current_frame ", QccIMGImageComponent *" reference_frame ", int " subpixel_accuracy ", const QccFilter *" filter1 ", const QccFilter *" filter2 ", const QccFilter *" filter3 );
.br
.sp
.BI "int QccVIDMotionEstimationCreateCompensatedFrame(QccIMGImageComponent *" motion_compensated_frame ", const QccIMGImageComponent *" reference_frame ", const QccIMGImageComponent *" motion_vectors_horizontal ", const QccIMGImageComponent *" motion_vectors_vertical ", int " block_size ", int " subpixel_accuracy );
.SH DESCRIPTION
.BR QccVIDMotionEstimationMAE()
calculates the mean absolute error (MAE) between
.I current_block
and
.I reference_block
where both blocks have
a block size of
.IR block_size 
by
.IR block_size .
.LP
.BR QccVIDMotionEstimationExtractBlock()
extracts a
.I block
of size
.I block_size
by
.I block_size
from
.IR image .
The block is extracted from location
.RI ( row ", " col ),
where this location is the upper-left corner of the block to extact.
.I subpixel_accuracy
is one of
.BR QCCVID_ME_FULLPIXEL ,
.BR QCCVID_ME_HALFPIXEL ,
.BR QCCVID_ME_QUARTERPIXEL ,
or 
.BR QCCVID_ME_EIGHTHPIXEL ,
indicating full-, half-, quarter-, or eighth-pixel accuracy.
Unless the accuracy is full-pixel,
.I image
is assumed to be interpolated to support motion-estimation at
the specified accuracy (using
.BR QccVIDMotionEstimationCreateReferenceFrame()
described below).
Unless the accuracy is full-pixel,
.I row
and
.I col
refer to the location in the original image, not the
interpolated image.
.LP
.BR QccVIDMotionEstimationInsertBlock()
does the inverse of
.BR QccVIDMotionEstimationExtractBlock() ;
that is, it inserts
.I block
into the specified location in
.IR image .
.LP
.BR QccVIDMotionEstimationFullSearch()
does full-search, block-based motion estimation in
.IR current_frame
using
.IR reference_frame
as the reference frame. That is,
for each block in
.IR current_frame ,
every block in a window surrounding the current-block location
in
.IR reference_frame
is searched, and the best-matching block chosen.
The motion vectors indicating the displacement from the blocks
in
.I current_frame
to their matching blocks in
.IR reference_frame
are returned in
.I motion_vectors_horizontal
and
.IR motion_vectors_vertical ,
which are the horizontal and vertical components
of the motion vectors, respectively.
.I block_size
gives the size of the blocks to match.
.I window_size
gives the size of the window to search in
.IR reference_frame
.RI ( window_size
should be positive, so that the search window is
.I -window_size
to
.IR +window_size ) .
.I subpixel_accuracy
is one of
.BR QCCVID_ME_FULLPIXEL ,
.BR QCCVID_ME_HALFPIXEL ,
.BR QCCVID_ME_QUARTERPIXEL ,
or 
.BR QCCVID_ME_EIGHTHPIXEL ,
indicating full-, half-, quarter-, or eighth-pixel motion-estimation accuracy.
It is assumed that
.IR reference_frame
is already interpolated to support the specified accuracy using
.BR QccVIDMotionEstimationCreateReferenceFrame() .
.LP
.BR QccVIDMotionEstimationCalcReferenceFrameSize()
returns the size that a reference frame needs to be to support
motion-estimation accuracy of the specified
.IR subpixel_accuracy .
.I num_rows
and
.I num_cols
give the original size of the frame;
the size of the interpolated reference frame is returned in
.I reference_num_rows
and
.IR reference_num_cols .
.LP
.BR QccVIDMotionEstimationCreateReferenceFrame()
interpolates
.I current_frame
into
.IR reference_frame 
at the specified
.IR subpixel_accuracy .
If
.IR subpixel_accuracy
is
.BR QCCVID_ME_FULLPIXEL ,
.I current_frame
is simply copied into
.IR reference_frame .
If
.IR subpixel_accuracy
is
.BR QCCVID_ME_HALFPIXEL ,
and
.IR filter1
is not
.BR NULL ,
then
.IR current_frame
is filtered into
.IR reference_frame
using
.BR QccIMGImageComponentInterpolateFilter (3).
On the other hand, if
.I filter1
is
.BR NULL ,
then bilinear interpolation is performed via
.BR QccIMGImageComponentInterpolateBilinear (3).
Similarly, if
.IR subpixel_accuracy
is
.BR QCCVID_ME_QUARTERPIXEL ,
then
.IR filter1
and
.IR filter2
determine whether bilinear or filtered interpolation is
used to go from full-pixel to half-pixel accuracy
.RI ( filter1 ),
and from half-pixel to quarter-pixel accuracy
.RI ( filter2 ).
Likewise,
.IR filter3
determines whether bilinear or filtered interpolation
is used in going from quarter-pixel to eighth-pixel accuracy when
.IR subpixel_accuracy
is
.BR QCCVID_ME_EIGHTHPIXEL .
.LP
.BR QccVIDMotionEstimationCreateCompensatedFrame()
extracts blocks from
.IR reference_frame
to create
.IR motion_compensated_frame ,
where the blocks are extracted according to the specified motion field as
given by
.IR motion_vectors_horizontal
and
.IR motion_vectors_vertical .
.I block_size
gives the size of the blocks, and
.IR subpixel_accuracy
indicates the subpixel accuracy of
.IR reference_frame .
It is assumed that
.IR reference_frame
is interpolated with
.BR QccVIDMotionEstimationCreateReferenceFrame()
to the specified
.IR subpixel_accuracy .
.SH "RETURN VALUE"
These routines return 0 on success, and 1 on failure.
.SH "SEE ALSO"
.BR QccVIDMotionVectorsEncode (3),
.BR QccVIDMotionVectorsDecode (3),
.BR memc (1),
.BR QccPackVID (3),
.BR QccPackENT (3),
.BR QccPack (3)
.SH AUTHOR
Copyright (C) 1997-2007  James E. Fowler
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