我通过非常小的步长进行图像翻译（比如在1/1024栏中翻译）
考虑我有以下图像（我使用＆＃34; Mat＆＃34;在opencv中创建图像并使用CV_64F类型）：
255 0
0 0
现在通过（1/1024）列进行翻译，我希望如下：
254.7509765625 0.2490234375
0 0
但我得到的是相同的源图像！：
255 0
0 0
如何获得预期结果？
以下是我正在进行翻译的代码：
Mat sourceImg = (Mat_<double>(2, 2) << 255.0, 0, 0, 0);
double translateColumn, translateRow;
translateColumn = 1.0/1024.0;
translateRow = 0.0;
Mat translationMatrix = (Mat_<double>(2, 3) << 1, 0, translateColumn, 0, 1, translateRow);
Mat translatedImage;
warpAffine(sourceImage, translatedImage, translationMatrix , sourceImage.size());
任何想法都会受到赞赏。
答案 0 :(得分：3)
找到文件中不精确的原因
imgproc.hpp
插值使用预先计算的查找表，使用的位数定义了这些表的大小和近似的准确性。
似乎它在片段中定义：
enum InterpolationMasks {
INTER_BITS = 5,
INTER_BITS2 = INTER_BITS * 2,
INTER_TAB_SIZE = 1 << INTER_BITS,
INTER_TAB_SIZE2 = INTER_TAB_SIZE * INTER_TAB_SIZE
};
或者，您可以使用此方法（在网络中找到）：
/*
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* modification, are permitted provided that the following conditions
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* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* File: shift.hpp
* Author: Hilton Bristow
* Created: Aug 23, 2012
*/
#ifndef SHIFT_HPP_
#define SHIFT_HPP_
#include <limits>
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
/*! @brief shift the values in a matrix by an (x,y) offset
*
* Given a matrix and an integer (x,y) offset, the matrix will be shifted
* such that:
*
* src(a,b) ---> dst(a+y,b+x)
*
* In the case of a non-integer offset, (e.g. cv::Point2f(-2.1, 3.7)),
* the shift will be calculated with subpixel precision using bilinear
* interpolation.
*
* All valid OpenCV datatypes are supported. If the source datatype is
* fixed-point, and a non-integer offset is supplied, the output will
* be a floating point matrix to preserve subpixel accuracy.
*
* All border types are supported. If no border type is supplied, the
* function defaults to BORDER_CONSTANT with 0-padding.
*
* The function supports in-place operation.
*
* Some common examples are provided following:
* \code
* // read an image from file
* Mat mat = imread(filename);
* Mat dst;
*
* // Perform Matlab-esque 'circshift' in-place
* shift(mat, mat, Point(5, 5), BORDER_WRAP);
*
* // Perform shift with subpixel accuracy, padding the missing pixels with 1s
* // NOTE: if mat is of type CV_8U, then it will be converted to type CV_32F
* shift(mat, mat, Point2f(-13.7, 3.28), BORDER_CONSTANT, 1);
*
* // Perform subpixel shift, preserving the boundary values
* shift(mat, dst, Point2f(0.093, 0.125), BORDER_REPLICATE);
*
* // Perform a vanilla shift, integer offset, very fast
* shift(mat, dst, Point(2, 2));
* \endcode
*
* @param src the source matrix
* @param dst the destination matrix, can be the same as source
* @param delta the amount to shift the matrix in (x,y) coordinates. Can be
* integer of floating point precision
* @param fill the method used to fill the null entries, defaults to BORDER_CONSTANT
* @param value the value of the null entries if the fill type is BORDER_CONSTANT
*/
void shift(const cv::Mat& src, cv::Mat& dst, cv::Point2f delta, int fill=cv::BORDER_CONSTANT, cv::Scalar value=cv::Scalar(0,0,0,0)) {
// error checking
assert(fabs(delta.x) < src.cols && fabs(delta.y) < src.rows);
// split the shift into integer and subpixel components
cv::Point2i deltai(ceil(delta.x), ceil(delta.y));
cv::Point2f deltasub(fabs(delta.x - deltai.x), fabs(delta.y - deltai.y));
// INTEGER SHIFT
// first create a border around the parts of the Mat that will be exposed
int t = 0, b = 0, l = 0, r = 0;
if (deltai.x > 0) l = deltai.x;
if (deltai.x < 0) r = -deltai.x;
if (deltai.y > 0) t = deltai.y;
if (deltai.y < 0) b = -deltai.y;
cv::Mat padded;
cv::copyMakeBorder(src, padded, t, b, l, r, fill, value);
// SUBPIXEL SHIFT
float eps = std::numeric_limits<float>::epsilon();
if (deltasub.x > eps || deltasub.y > eps) {
switch (src.depth()) {
case CV_32F:
{
cv::Matx<float, 1, 2> dx(1-deltasub.x, deltasub.x);
cv::Matx<float, 2, 1> dy(1-deltasub.y, deltasub.y);
sepFilter2D(padded, padded, -1, dx, dy, cv::Point(0,0), 0, cv::BORDER_CONSTANT);
break;
}
case CV_64F:
{
cv::Matx<double, 1, 2> dx(1-deltasub.x, deltasub.x);
cv::Matx<double, 2, 1> dy(1-deltasub.y, deltasub.y);
sepFilter2D(padded, padded, -1, dx, dy, cv::Point(0,0), 0, cv::BORDER_CONSTANT);
break;
}
default:
{
cv::Matx<float, 1, 2> dx(1-deltasub.x, deltasub.x);
cv::Matx<float, 2, 1> dy(1-deltasub.y, deltasub.y);
padded.convertTo(padded, CV_32F);
sepFilter2D(padded, padded, CV_32F, dx, dy, cv::Point(0,0), 0, cv::BORDER_CONSTANT);
break;
}
}
}
// construct the region of interest around the new matrix
cv::Rect roi = cv::Rect(std::max(-deltai.x,0),std::max(-deltai.y,0),0,0) + src.size();
dst = padded(roi);
}
#endif /* SHIFT_HPP_ */
似乎工作正常。