/*===========================================================================*
* psearch.c
*
* Procedures concerned with the P-frame motion search
*
*===========================================================================*/
/*==============*
* HEADER FILES *
*==============*/
#include "all.h"
#include "mtypes.h"
#include "frames.h"
#include "motion_search.h"
#include "prototypes.h"
#include "fsize.h"
#include "param.h"
#include "subsample.h"
#include "block.h"
/*==================*
* STATIC VARIABLES *
*==================*/
/* none */
/*==================*
* GLOBAL VARIABLES *
*==================*/
int **pmvHistogram = NULL; /* histogram of P-frame motion vectors */
int **bbmvHistogram = NULL; /* histogram of B-frame bkwd motion vectors */
int **bfmvHistogram = NULL; /* histogram of B-frame fwd motion vectors */
int pixelFullSearch;
int searchRangeP,searchRangeB;
/* The range, in half pixels in each direction, that we are to search
when detecting motion. Specified by RANGE statement in parameter file.
*/
int psearchAlg;
/* specified by parameter file. */
/*===============================*
* INTERNAL PROCEDURE prototypes *
*===============================*/
/*=====================*
* EXPORTED PROCEDURES *
*=====================*/
/*===========================================================================*
*
* Compute the best P-frame motion vector we can. If it's better than
* *motionP, update *motionP to it.
*
* PRECONDITIONS: The relevant block in 'current' is valid (it has not
* been dct'd). Thus, the data in 'current' can be
* accesed through y_blocks, cr_blocks, and cb_blocks.
* This is not the case for the blocks in 'prev.'
* Therefore, references into 'prev' should be done
* through the struct items ref_y, ref_cr, ref_cb
*
* POSTCONDITIONS: current, prev unchanged.
* Some computation could be saved by requiring
* the dct'd difference to be put into current's block
* elements here, depending on the search technique.
* However, it was decided that it mucks up the code
* organization a little, and the saving in computation
* would be relatively little (if any).
*
* NOTES: the search procedure need not check the (0,0) motion vector
* the calling procedure has a preference toward (0,0) and it
* will check it itself
*
* SIDE EFFECTS: none
*
*===========================================================================*/
void
PMotionSearch(const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
vector * const motionP) {
/* CALL SEARCH PROCEDURE */
switch(psearchAlg) {
case PSEARCH_SUBSAMPLE:
PSubSampleSearch(currentBlockP, prev, by, bx, motionP, searchRangeP);
break;
case PSEARCH_EXHAUSTIVE:
PLocalSearch(currentBlockP, prev, by, bx,
motionP, INT_MAX, searchRangeP);
break;
case PSEARCH_LOGARITHMIC:
PLogarithmicSearch(currentBlockP, prev, by, bx, motionP, searchRangeP);
break;
case PSEARCH_TWOLEVEL:
PTwoLevelSearch(currentBlockP, prev, by, bx,
motionP, INT_MAX, searchRangeP);
break;
default:
pm_error("IMPOSSIBLE PSEARCH ALG: %d", psearchAlg);
}
}
/*===========================================================================*
*
* SetPixelSearch
*
* set the pixel search type (half or full)
*
* RETURNS: nothing
*
* SIDE EFFECTS: pixelFullSearch
*
*===========================================================================*/
void
SetPixelSearch(const char * const searchType) {
if ( (strcmp(searchType, "FULL") == 0 ) ||
( strcmp(searchType, "WHOLE") == 0 )) {
pixelFullSearch = TRUE;
} else if ( strcmp(searchType, "HALF") == 0 ) {
pixelFullSearch = FALSE;
} else {
fprintf(stderr, "ERROR: Invalid pixel search type: %s\n",
searchType);
exit(1);
}
}
/*===========================================================================*
*
* SetPSearchAlg
*
* set the P-search algorithm
*
* RETURNS: nothing
*
* SIDE EFFECTS: psearchAlg
*
*===========================================================================*/
void
SetPSearchAlg(const char * const alg)
{
if ( strcmp(alg, "EXHAUSTIVE") == 0 ) {
psearchAlg = PSEARCH_EXHAUSTIVE;
} else if (strcmp(alg, "SUBSAMPLE") == 0 ) {
psearchAlg = PSEARCH_SUBSAMPLE;
} else if ( strcmp(alg, "LOGARITHMIC") == 0 ) {
psearchAlg = PSEARCH_LOGARITHMIC;
} else if ( strcmp(alg, "TWOLEVEL") == 0 ) {
psearchAlg = PSEARCH_TWOLEVEL;
} else {
fprintf(stderr, "ERROR: Invalid psearch algorithm: %s\n", alg);
exit(1);
}
}
/*===========================================================================*
*
* PSearchName
*
* returns a string containing the name of the search algorithm
*
* RETURNS: pointer to the string
*
* SIDE EFFECTS: none
*
*===========================================================================*/
const char *
PSearchName(void)
{
const char *retval;
switch(psearchAlg) {
case PSEARCH_EXHAUSTIVE:
retval = "EXHAUSTIVE";break;
case PSEARCH_SUBSAMPLE:
retval = "SUBSAMPLE";break;
case PSEARCH_LOGARITHMIC:
retval = "LOGARITHMIC";break;
case PSEARCH_TWOLEVEL:
retval = "TWOLEVEL";break;
default:
fprintf(stderr, "ERROR: Illegal PSEARCH ALG: %d\n", psearchAlg);
exit(1);
break;
}
return retval;
}
/*===========================================================================*
*
* SetSearchRange
*
* sets the range of the search to the given number of pixels,
* allocate histogram storage
*
*===========================================================================*/
void
SetSearchRange(int const pixelsP, int const pixelsB) {
searchRangeP = 2*pixelsP; /* +/- 'pixels' pixels */
searchRangeB = 2*pixelsB;
if ( computeMVHist ) {
int const max_search = max(searchRangeP, searchRangeB);
int index;
pmvHistogram = (int **) malloc((2*searchRangeP+3)*sizeof(int *));
bbmvHistogram = (int **) malloc((2*searchRangeB+3)*sizeof(int *));
bfmvHistogram = (int **) malloc((2*searchRangeB+3)*sizeof(int *));
for ( index = 0; index < 2*max_search+3; index++ ) {
pmvHistogram[index] =
(int *) calloc(2*searchRangeP+3, sizeof(int));
bbmvHistogram[index] =
(int *) calloc(2*searchRangeB+3, sizeof(int));
bfmvHistogram[index] =
(int *) calloc(2*searchRangeB+3, sizeof(int));
}
}
}
/*===========================================================================*
*
* USER-MODIFIABLE
*
* MotionSearchPreComputation
*
* do whatever you want here; this is called once per frame, directly
* after reading
*
* RETURNS: whatever
*
* SIDE EFFECTS: whatever
*
*===========================================================================*/
void
MotionSearchPreComputation(MpegFrame * const frameP) {
/* do nothing */
}
/*===========================================================================*
*
* PSubSampleSearch
*
* uses the subsampling algorithm to compute the P-frame vector
*
* RETURNS: motion vector
*
* SIDE EFFECTS: none
*
* REFERENCE: Liu and Zaccarin: New Fast Algorithms for the Estimation
* of Block Motion Vectors, IEEE Transactions on Circuits
* and Systems for Video Technology, Vol. 3, No. 2, 1993.
*
*===========================================================================*/
int
PSubSampleSearch(const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
vector * const motionP,
int const searchRange) {
int my, mx;
int bestBestDiff;
int stepSize;
int x;
int bestMY[4], bestMX[4], bestDiff[4];
int leftMY, leftMX;
int rightMY, rightMX;
stepSize = (pixelFullSearch ? 2 : 1);
COMPUTE_MOTION_BOUNDARY(by,bx,stepSize,leftMY,leftMX,rightMY,rightMX);
if ( searchRange < rightMY ) {
rightMY = searchRange;
}
if ( searchRange < rightMX ) {
rightMX = searchRange;
}
for ( x = 0; x < 4; x++ ) {
bestMY[x] = 0;
bestMX[x] = 0;
bestDiff[x] = INT_MAX;
}
/* do A pattern */
for (my = -searchRange; my < rightMY; my += 2*stepSize) {
if (my >= leftMY) {
for ( mx = -searchRange; mx < rightMX; mx += 2*stepSize ) {
if (mx >= leftMX) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionErrorA(currentBlockP, prev, by, bx, m,
bestDiff[0]);
if (diff < bestDiff[0]) {
bestMY[0] = my;
bestMX[0] = mx;
bestDiff[0] = diff;
}
}
}
}
}
/* do B pattern */
for (my = stepSize-searchRange; my < rightMY; my += 2*stepSize) {
if (my >= leftMY) {
for (mx = -searchRange; mx < rightMX; mx += 2*stepSize) {
if (mx >= leftMX) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionErrorB(currentBlockP, prev, by, bx, m,
bestDiff[1]);
if (diff < bestDiff[1]) {
bestMY[1] = my;
bestMX[1] = mx;
bestDiff[1] = diff;
}
}
}
}
}
/* do C pattern */
for (my = stepSize-searchRange; my < rightMY; my += 2*stepSize) {
if (my >= leftMY) {
for ( mx = stepSize-searchRange; mx < rightMX; mx += 2*stepSize ) {
if (mx >= leftMX) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionErrorC(currentBlockP, prev, by, bx, m,
bestDiff[2]);
if (diff < bestDiff[2]) {
bestMY[2] = my;
bestMX[2] = mx;
bestDiff[2] = diff;
}
}
}
}
}
/* do D pattern */
for (my = -searchRange; my < rightMY; my += 2*stepSize) {
if (my >= leftMY) {
for (mx = stepSize-searchRange; mx < rightMX; mx += 2*stepSize) {
if (mx >= leftMX) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionErrorD(currentBlockP, prev, by, bx, m,
bestDiff[3]);
if (diff < bestDiff[3]) {
bestMY[3] = my;
bestMX[3] = mx;
bestDiff[3] = diff;
}
}
}
}
}
/* first check old motion */
if ((motionP->y >= leftMY) && (motionP->y < rightMY) &&
(motionP->x >= leftMX) && (motionP->x < rightMX)) {
bestBestDiff = LumMotionError(currentBlockP, prev, by, bx,
*motionP, INT_MAX);
} else
bestBestDiff = INT_MAX;
/* look at Error of 4 different motion vectors */
for (x = 0; x < 4; ++x) {
vector m;
m.y = bestMY[x];
m.x = bestMX[x];
bestDiff[x] = LumMotionError(currentBlockP, prev, by, bx, m,
bestBestDiff);
if (bestDiff[x] < bestBestDiff) {
bestBestDiff = bestDiff[x];
*motionP = m;
}
}
return bestBestDiff;
}
static void
findBestSpaced(int const minMY,
int const minMX,
int const maxMY,
int const maxMX,
int const spacing,
const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
int * const bestDiffP,
vector * const centerP) {
/*----------------------------------------------------------------------------
Examine every 'spacing'th half-pixel within the rectangle
('minBoundX', 'minBoundY', 'maxBoundX', 'maxBoundY'),
If one of the half-pixels examined has a lower "LumMotionError" value
than *bestDiffP, update *bestDiffP to that value and update
*centerP to the location of that half-pixel.
-----------------------------------------------------------------------------*/
int const minBoundY = MAX(minMY, centerP->y - spacing);
int const minBoundX = MAX(minMX, centerP->x - spacing);
int const maxBoundY = MIN(maxMY, centerP->y + spacing + 1);
int const maxBoundX = MIN(maxMX, centerP->x + spacing + 1);
int my;
for (my = minBoundY; my < maxBoundY; my += spacing) {
int mx;
for (mx = minBoundX; mx < maxBoundX; mx += spacing) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionError(currentBlockP, prev, by, bx, m, *bestDiffP);
if (diff < *bestDiffP) {
*centerP = m;
*bestDiffP = diff;
}
}
}
}
/*===========================================================================*
*
* PLogarithmicSearch
*
* uses logarithmic search to compute the P-frame vector
*
* RETURNS: motion vector
*
* SIDE EFFECTS: none
*
* REFERENCE: MPEG-I specification, pages 32-33
*
*===========================================================================*/
int
PLogarithmicSearch(const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
vector * const motionP,
int const searchRange) {
int const stepSize = (pixelFullSearch ? 2 : 1);
int minMY, minMX, maxMY, maxMX;
int spacing; /* grid spacing */
vector motion;
/* Distance from (bx,by) (in half-pixels) of the block that is most
like the current block among those that we have examined so far.
(0,0) means we haven't examined any.
*/
int bestDiff;
/* The difference between the current block and the block offset
'motion' from it.
*/
COMPUTE_MOTION_BOUNDARY(by, bx, stepSize, minMY, minMX, maxMY, maxMX);
minMX = max(minMX, - searchRange);
minMY = max(minMY, - searchRange);
maxMX = min(maxMX, + searchRange);
maxMY = min(maxMY, + searchRange);
/* Note: The clipping to 'searchRange' above may seem superfluous because
the basic algorithm would never want to look more than 'searchRange'
pixels away, but with rounding error, it can.
*/
motion.x = motion.y = 0;
bestDiff = INT_MAX;
for (spacing = searchRange; spacing >= stepSize;) {
if (stepSize == 2) { /* make sure spacing is even */
if (spacing == 2)
spacing = 0;
else {
spacing = (spacing+1)/2;
if (spacing % 2 != 0)
--spacing;
}
} else {
if (spacing == 1) {
spacing = 0;
} else
spacing = (spacing + 1) / 2;
}
if (spacing >= stepSize)
findBestSpaced(minMY, minMX, maxMY, maxMX,
spacing, currentBlockP, prev, by, bx,
&bestDiff, &motion);
}
{
int diff;
/* check old motion -- see if it's better */
if ((motionP->y >= minMY) && (motionP->y < maxMY) &&
(motionP->x >= minMX) && (motionP->x < maxMX)) {
diff = LumMotionError(currentBlockP, prev, by, bx,
*motionP, bestDiff);
} else
diff = INT_MAX;
if (bestDiff < diff)
*motionP = motion;
else
bestDiff = diff;
}
return bestDiff;
}
/*===========================================================================*
*
* PLocalSearch
*
* uses local exhaustive search to compute the P-frame vector
*
* RETURNS: motion vector
*
* SIDE EFFECTS: none
*
*===========================================================================*/
int
PLocalSearch(const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
vector * const motionP,
int const bestSoFar,
int const searchRange) {
int mx, my;
int bestDiff;
int stepSize;
int leftMY, leftMX;
int rightMY, rightMX;
int distance;
int tempRightMY, tempRightMX;
stepSize = (pixelFullSearch ? 2 : 1);
COMPUTE_MOTION_BOUNDARY(by,bx,stepSize,leftMY,leftMX,rightMY,rightMX);
/* try old motion vector first */
if (VALID_MOTION(*motionP)) {
bestDiff = LumMotionError(currentBlockP, prev, by, bx,
*motionP, bestSoFar);
if (bestSoFar < bestDiff)
bestDiff = bestSoFar;
} else {
motionP->y = motionP->x = 0;
bestDiff = bestSoFar;
}
/* try a spiral pattern */
for (distance = stepSize; distance <= searchRange; distance += stepSize) {
tempRightMY = MIN(distance, rightMY);
tempRightMX = MIN(distance, rightMX);
/* do top, bottom */
for (my = -distance; my < tempRightMY;
my += max(tempRightMY+distance-stepSize, stepSize)) {
if (my >= leftMY) {
for ( mx = -distance; mx < tempRightMX; mx += stepSize ) {
if (mx >= leftMX) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionError(currentBlockP, prev, by, bx, m,
bestDiff);
if (diff < bestDiff) {
*motionP = m;
bestDiff = diff;
}
}
}
}
}
/* do left, right */
for (mx = -distance; mx < tempRightMX;
mx += max(tempRightMX+distance-stepSize, stepSize)) {
if (mx >= leftMX) {
for (my = -distance+stepSize; my < tempRightMY-stepSize;
my += stepSize) {
if (my >= leftMY) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionError(currentBlockP, prev, by, bx, m,
bestDiff);
if (diff < bestDiff) {
*motionP = m;
bestDiff = diff;
}
}
}
}
}
}
return bestDiff;
}
/*===========================================================================*
*
* PTwoLevelSearch
*
* uses two-level search to compute the P-frame vector
* first does exhaustive full-pixel search, then looks at neighboring
* half-pixel motion vectors
*
* RETURNS: motion vector
*
* SIDE EFFECTS: none
*
*===========================================================================*/
int
PTwoLevelSearch(const LumBlock * const currentBlockP,
MpegFrame * const prev,
int const by,
int const bx,
vector * const motionP,
int const bestSoFar,
int const searchRange) {
int mx, my;
int loopInc;
int diff, bestDiff;
int leftMY, leftMX;
int rightMY, rightMX;
int distance;
int tempRightMY, tempRightMX;
int xOffset, yOffset;
/* exhaustive full-pixel search first */
COMPUTE_MOTION_BOUNDARY(by,bx,2,leftMY,leftMX,rightMY,rightMX);
rightMY--;
rightMX--;
/* convert vector into full-pixel vector */
if (motionP->y > 0) {
if ((motionP->y % 2) == 1) {
--motionP->y;
}
} else if (((-motionP->y) % 2) == 1)
++motionP->y;
if (motionP->x > 0) {
if ((motionP->x % 2) == 1)
--motionP->x;
} else if ((-motionP->x % 2) == 1)
++motionP->x;
/* try old motion vector first */
if (VALID_MOTION(*motionP)) {
bestDiff = LumMotionError(currentBlockP, prev, by, bx,
*motionP, bestSoFar);
if ( bestSoFar < bestDiff ) {
bestDiff = bestSoFar;
}
} else {
motionP->y = motionP->x = 0;
bestDiff = bestSoFar;
}
++rightMY;
++rightMX;
/* try a spiral pattern */
for ( distance = 2; distance <= searchRange; distance += 2 ) {
tempRightMY = MIN(distance, rightMY);
tempRightMX = MIN(distance, rightMX);
/* do top, bottom */
loopInc = max(tempRightMY + distance - 2, 2);
for (my = -distance; my < tempRightMY; my += loopInc) {
if (my >= leftMY) {
for (mx = -distance; mx < tempRightMX; mx += 2) {
if (mx >= leftMX) {
vector m;
m.y = my; m.x = mx;
diff = LumMotionError(currentBlockP, prev, by, bx, m,
bestDiff);
if (diff < bestDiff) {
*motionP = m;
bestDiff = diff;
}
}
}
}
}
/* do left, right */
loopInc = max(tempRightMX+distance-2, 2);
for (mx = -distance; mx < tempRightMX; mx += loopInc) {
if (mx >= leftMX) {
for ( my = -distance+2; my < tempRightMY-2; my += 2 ) {
if (my >= leftMY) {
int diff;
vector m;
m.y = my; m.x = mx;
diff = LumMotionError(currentBlockP, prev, by, bx, m,
bestDiff);
if ( diff < bestDiff ) {
*motionP = m;
bestDiff = diff;
}
}
}
}
}
}
/* now look at neighboring half-pixels */
my = motionP->y;
mx = motionP->x;
--rightMY;
--rightMX;
for (yOffset = -1; yOffset <= 1; ++yOffset) {
for (xOffset = -1; xOffset <= 1; ++xOffset) {
if ((yOffset != 0) || (xOffset != 0)) {
vector m;
m.y = my+yOffset; m.x = mx+xOffset;
if (VALID_MOTION(m)) {
int diff;
diff = LumMotionError(currentBlockP, prev, by, bx,
m, bestDiff);
if (diff < bestDiff) {
*motionP = m;
bestDiff = diff;
}
}
}
}
}
return bestDiff;
}
void
ShowPMVHistogram(fpointer)
FILE *fpointer;
{
register int x, y;
int *columnTotals;
int rowTotal;
columnTotals = (int *) calloc(2*searchRangeP+3, sizeof(int));
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, " ");
for ( y = 0; y < 2*searchRange+3; y++ ) {
fprintf(fpointer, "%3d ", y-searchRangeP-1);
}
fprintf(fpointer, "\n");
#endif
for ( x = 0; x < 2*searchRangeP+3; x++ ) {
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%3d ", x-searchRangeP-1);
#endif
rowTotal = 0;
for ( y = 0; y < 2*searchRangeP+3; y++ ) {
fprintf(fpointer, "%3d ", pmvHistogram[x][y]);
rowTotal += pmvHistogram[x][y];
columnTotals[y] += pmvHistogram[x][y];
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%4d\n", rowTotal);
#else
fprintf(fpointer, "\n");
#endif
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "Tot ");
for ( y = 0; y < 2*searchRangeP+3; y++ ) {
fprintf(fpointer, "%3d ", columnTotals[y]);
}
#endif
fprintf(fpointer, "\n");
}
void
ShowBBMVHistogram(fpointer)
FILE *fpointer;
{
register int x, y;
int *columnTotals;
int rowTotal;
fprintf(fpointer, "B-frame Backwards:\n");
columnTotals = (int *) calloc(2*searchRangeB+3, sizeof(int));
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, " ");
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", y-searchRangeB-1);
}
fprintf(fpointer, "\n");
#endif
for ( x = 0; x < 2*searchRangeB+3; x++ ) {
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%3d ", x-searchRangeB-1);
#endif
rowTotal = 0;
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", bbmvHistogram[x][y]);
rowTotal += bbmvHistogram[x][y];
columnTotals[y] += bbmvHistogram[x][y];
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%4d\n", rowTotal);
#else
fprintf(fpointer, "\n");
#endif
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "Tot ");
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", columnTotals[y]);
}
#endif
fprintf(fpointer, "\n");
}
void
ShowBFMVHistogram(fpointer)
FILE *fpointer;
{
register int x, y;
int *columnTotals;
int rowTotal;
fprintf(fpointer, "B-frame Forwards:\n");
columnTotals = (int *) calloc(2*searchRangeB+3, sizeof(int));
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, " ");
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", y-searchRangeB-1);
}
fprintf(fpointer, "\n");
#endif
for ( x = 0; x < 2*searchRangeB+3; x++ ) {
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%3d ", x-searchRangeB-1);
#endif
rowTotal = 0;
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", bfmvHistogram[x][y]);
rowTotal += bfmvHistogram[x][y];
columnTotals[y] += bfmvHistogram[x][y];
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "%4d\n", rowTotal);
#else
fprintf(fpointer, "\n");
#endif
}
#ifdef COMPLETE_DISPLAY
fprintf(fpointer, "Tot ");
for ( y = 0; y < 2*searchRangeB+3; y++ ) {
fprintf(fpointer, "%3d ", columnTotals[y]);
}
#endif
fprintf(fpointer, "\n");
}
/*
* Copyright (c) 1995 The Regents of the University of California.
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose, without fee, and without written agreement is
* hereby granted, provided that the above copyright notice and the following
* two paragraphs appear in all copies of this software.
*
* IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
* CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
/*
* $Header: /u/smoot/md/mpeg_encode/RCS/psearch.c,v 1.9 1995/01/19 23:09:12 eyhung Exp $
* $Log: psearch.c,v $
* Revision 1.9 1995/01/19 23:09:12 eyhung
* Changed copyrights
*
* Revision 1.9 1995/01/19 23:09:12 eyhung
* Changed copyrights
*
* Revision 1.8 1994/12/07 00:40:36 smoot
* Added separate P and B search ranges
*
* Revision 1.7 1994/11/12 02:09:45 eyhung
* full pixel bug
* fixed on lines 512 and 563
*
* Revision 1.6 1994/03/15 00:27:11 keving
* nothing
*
* Revision 1.5 1993/12/22 19:19:01 keving
* nothing
*
* Revision 1.4 1993/07/22 22:23:43 keving
* nothing
*
* Revision 1.3 1993/06/30 20:06:09 keving
* nothing
*
* Revision 1.2 1993/06/03 21:08:08 keving
* nothing
*
* Revision 1.1 1993/03/02 18:27:05 keving
* nothing
*
*/