作者：gnuhpc
出处：http://www.cnblogs.com/gnuhpc/
#include <stdio.h>
#include "cxcore.h"
int main( int argc, char** argv )
{
CvFileStorage* fs = cvOpenFileStorage( "points.yaml", 0, CV_STORAGE_READ );
/*所有已读存储在文件元素的关键字被存储在hash表中，
它使用哈希指针“x”和“y"加速对点的解析。这样可以加速查找操作 */
CvStringHashNode* x_key = cvGetHashedKey( fs, "x", -1, 1 );
CvStringHashNode* y_key = cvGetHashedKey( fs, "y", -1, 1 );
CvFileNode* points = cvGetFileNodeByName( fs, 0, "points" );
if( CV_NODE_IS_SEQ(points->tag) )
{
CvSeq* seq = points->data.seq;
int i, total = seq->total;
CvSeqReader reader;
cvStartReadSeq( seq, &reader, 0 );
for( i = 0; i < total; i++ )
{
CvFileNode* pt = (CvFileNode*)reader.ptr;
#if 1 /* 快变量 */
CvFileNode* xnode = cvGetFileNode( fs, pt, x_key, 0 );
CvFileNode* ynode = cvGetFileNode( fs, pt, y_key, 0 );
assert( xnode && CV_NODE_IS_INT(xnode->tag) &&
ynode && CV_NODE_IS_INT(ynode->tag));
int x = xnode->data.i; // or x = cvReadInt( xnode, 0 );
int y = ynode->data.i; // or y = cvReadInt( ynode, 0 );
#elif 1 /* 慢变量：不使用x值与y值 */
CvFileNode* xnode = cvGetFileNodeByName( fs, pt, "x" );
CvFileNode* ynode = cvGetFileNodeByName( fs, pt, "y" );
assert( xnode && CV_NODE_IS_INT(xnode->tag) &&
ynode && CV_NODE_IS_INT(ynode->tag));
int x = xnode->data.i; // or x = cvReadInt( xnode, 0 );
int y = ynode->data.i; // or y = cvReadInt( ynode, 0 );
#else /* 最慢的可以轻松使用的变量 */
int x = cvReadIntByName( fs, pt, "x", 0 /* default value */ );
int y = cvReadIntByName( fs, pt, "y", 0 /* default value */ );
#endif
CV_NEXT_SEQ_ELEM( seq->elem_size, reader );
printf("%d: (%d, %d)/n", i, x, y );
}
}
cvReleaseFileStorage( &fs );
return 0;
}