/*!
* \brief pixRotateShear()
*
* \param[in] pixs
* \param[in] xcen x value for which there is no horizontal shear
* \param[in] ycen y value for which there is no vertical shear
* \param[in] angle radians
* \param[in] incolor L_BRING_IN_WHITE, L_BRING_IN_BLACK;
* \return pixd, or NULL on error.
*
* <pre>
* Notes:
* (1) This rotates an image about the given point, using
* either 2 or 3 shears.
* (2) A positive angle gives a clockwise rotation.
* (3) This brings in 'incolor' pixels from outside the image.
* (4) For rotation angles larger than about 0.35 radians, we issue
* a warning because you should probably be using another method
* (either sampling or area mapping)
* </pre>
*/
PIX *
pixRotateShear(PIX *pixs,
l_int32 xcen,
l_int32 ycen,
l_float32 angle,
l_int32 incolor)
{
PROCNAME("pixRotateShear");
if (!pixs)
return (PIX *)(PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (incolor != L_BRING_IN_WHITE && incolor != L_BRING_IN_BLACK)
return (PIX *)(PIX *)ERROR_PTR("invalid incolor value", procName, NULL);
if (L_ABS(angle) < MIN_ANGLE_TO_ROTATE)
return pixClone(pixs);
if (L_ABS(angle) <= MAX_2_SHEAR_ANGLE)
return pixRotate2Shear(pixs, xcen, ycen, angle, incolor);
if (L_ABS(angle) > LIMIT_SHEAR_ANGLE)
L_WARNING("%6.2f radians; large angle for shear rotation\n",
procName, L_ABS(angle));
return pixRotate3Shear(pixs, xcen, ycen, angle, incolor);
}
/*!
* \brief pixRotate2Shear()
*
* \param[in] pixs
* \param[in] xcen, ycen center of rotation
* \param[in] angle radians
* \param[in] incolor L_BRING_IN_WHITE, L_BRING_IN_BLACK;
* \return pixd, or NULL on error.
*
* <pre>
* Notes:
* (1) This rotates the image about the given point, using the 2-shear
* method. It should only be used for angles smaller than
* MAX_2_SHEAR_ANGLE. For larger angles, a warning is issued.
* (2) A positive angle gives a clockwise rotation.
* (3) 2-shear rotation by a specified angle is equivalent
* to the sequential transformations
* x' = x + tan(angle) * (y - ycen) for x-shear
* y' = y + tan(angle) * (x - xcen) for y-shear
* (4) Computation of tan(angle) is performed within the shear operation.
* (5) This brings in 'incolor' pixels from outside the image.
* (6) If the image has an alpha layer, it is rotated separately by
* two shears.
* </pre>
*/
PIX *
pixRotate2Shear(PIX *pixs,
l_int32 xcen,
l_int32 ycen,
l_float32 angle,
l_int32 incolor)
{
PIX *pix1, *pix2, *pixd;
PROCNAME("pixRotate2Shear");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (incolor != L_BRING_IN_WHITE && incolor != L_BRING_IN_BLACK)
return (PIX *)(PIX *)ERROR_PTR("invalid incolor value", procName, NULL);
if (L_ABS(angle) < MIN_ANGLE_TO_ROTATE)
return pixClone(pixs);
if (L_ABS(angle) > MAX_2_SHEAR_ANGLE)
L_WARNING("%6.2f radians; large angle for 2-shear rotation\n",
procName, L_ABS(angle));
if ((pix1 = pixHShear(NULL, pixs, ycen, angle, incolor)) == NULL)
return (PIX *)ERROR_PTR("pix1 not made", procName, NULL);
pixd = pixVShear(NULL, pix1, xcen, angle, incolor);
pixDestroy(&pix1);
if (!pixd)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
if (pixGetDepth(pixs) == 32 && pixGetSpp(pixs) == 4) {
pix1 = pixGetRGBComponent(pixs, L_ALPHA_CHANNEL);
/* L_BRING_IN_WHITE brings in opaque for the alpha component */
pix2 = pixRotate2Shear(pix1, xcen, ycen, angle, L_BRING_IN_WHITE);
pixSetRGBComponent(pixd, pix2, L_ALPHA_CHANNEL);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
return pixd;
}
/*!
* pixRotateShear()
*
* Input: pixs
* xcen (x value for which there is no horizontal shear)
* ycen (y value for which there is no vertical shear)
* angle (radians)
* incolor (L_BRING_IN_WHITE, L_BRING_IN_BLACK);
* Return: pixd, or null on error.
*
* Notes:
* (1) This rotates an image about the given point, using
* either 2 or 3 shears.
* (2) A positive angle gives a clockwise rotation.
* (3) This brings in 'incolor' pixels from outside the image.
*/
PIX *
pixRotateShear(PIX *pixs,
l_int32 xcen,
l_int32 ycen,
l_float32 angle,
l_int32 incolor)
{
PROCNAME("pixRotateShear");
if (!pixs)
return (PIX *)(PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (incolor != L_BRING_IN_WHITE && incolor != L_BRING_IN_BLACK)
return (PIX *)(PIX *)ERROR_PTR("invalid incolor value", procName, NULL);
if (L_ABS(angle) < VERY_SMALL_ANGLE)
return pixClone(pixs);
if (L_ABS(angle) <= MAX_2_SHEAR_ANGLE)
return pixRotate2Shear(pixs, xcen, ycen, angle, incolor);
else
return pixRotate3Shear(pixs, xcen, ycen, angle, incolor);
}
int main(int argc,
char **argv)
{
l_int32 w, h, x, y, i, n;
l_float32 *vc;
PIX *pix1, *pix2, *pix3, *pix4, *pix5;
PIXA *pixas, *pixa;
L_REGPARAMS *rp;
if (regTestSetup(argc, argv, &rp))
return 1;
pixas = pixaCreate(11);
for (i = 0; i < 10; i++) { /* this preserves any alpha */
pix1 = pixRead(fnames[i]);
pix2 = pixScaleBySamplingToSize(pix1, 250, 150);
pixaAddPix(pixas, pix2, L_INSERT);
pixDestroy(&pix1);
}
/* Add a transparent grid over the rgb image */
pix1 = pixaGetPix(pixas, 8, L_COPY);
pixGetDimensions(pix1, &w, &h, NULL);
pix2 = pixCreate(w, h, 1);
for (i = 0; i < 5; i++) {
y = h * (i + 1) / 6;
pixRenderLine(pix2, 0, y, w, y, 3, L_SET_PIXELS);
}
for (i = 0; i < 7; i++) {
x = w * (i + 1) / 8;
pixRenderLine(pix2, x, 0, x, h, 3, L_SET_PIXELS);
}
pix3 = pixConvertTo8(pix2, 0); /* 1 --> 0 ==> transparent */
pixSetRGBComponent(pix1, pix3, L_ALPHA_CHANNEL);
pixaAddPix(pixas, pix1, L_INSERT);
n = pixaGetCount(pixas);
pixDestroy(&pix2);
pixDestroy(&pix3);
#if DO_ALL
/* Display with and without removing alpha with white bg */
pix1 = pixaDisplayTiledInRows(pixas, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 0 */
pixDisplayWithTitle(pix1, 0, 0, NULL, rp->display);
pixDestroy(&pix1);
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRemoveAlpha(pix1);
pixaAddPix(pixa, pix2, L_INSERT);
pixDestroy(&pix1);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 1 */
pixDisplayWithTitle(pix1, 200, 0, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Setting to gray */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pixSetAllGray(pix1, 170);
pix2 = pixRemoveAlpha(pix1);
pixaAddPix(pixa, pix2, L_INSERT);
pixDestroy(&pix1);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 2 */
pixDisplayWithTitle(pix1, 400, 0, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* General scaling */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixScaleToSize(pix1, 350, 650);
pix3 = pixScaleToSize(pix2, 200, 200);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 3 */
pixDisplayWithTitle(pix1, 600, 0, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Scaling by sampling */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixScaleBySamplingToSize(pix1, 350, 650);
pix3 = pixScaleBySamplingToSize(pix2, 200, 200);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 4 */
pixDisplayWithTitle(pix1, 800, 0, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by area mapping; no embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_AREA_MAP,
L_BRING_IN_WHITE, 0, 0);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_AREA_MAP,
L_BRING_IN_WHITE, 0, 0);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 5 */
pixDisplayWithTitle(pix1, 1000, 0, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by area mapping; with embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_AREA_MAP,
L_BRING_IN_WHITE, 250, 150);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_AREA_MAP,
L_BRING_IN_WHITE, 250, 150);
pix4 = pixRemoveBorderToSize(pix3, 250, 150);
pix5 = pixRemoveAlpha(pix4);
pixaAddPix(pixa, pix5, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
pixDestroy(&pix4);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 6 */
pixDisplayWithTitle(pix1, 0, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by 3-shear; no embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_SHEAR,
L_BRING_IN_WHITE, 0, 0);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_SHEAR,
L_BRING_IN_WHITE, 0, 0);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 7 */
pixDisplayWithTitle(pix1, 200, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by 3-shear; with embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_SHEAR,
L_BRING_IN_WHITE, 250, 150);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_SHEAR,
L_BRING_IN_WHITE, 250, 150);
pix4 = pixRemoveBorderToSize(pix3, 250, 150);
pix5 = pixRemoveAlpha(pix4);
pixaAddPix(pixa, pix5, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
pixDestroy(&pix4);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 8 */
pixDisplayWithTitle(pix1, 400, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by 2-shear about the center */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pixGetDimensions(pix1, &w, &h, NULL);
pix2 = pixRotate2Shear(pix1, w / 2, h / 2, 0.25, L_BRING_IN_WHITE);
pix3 = pixRotate2Shear(pix2, w / 2, h / 2, -0.35, L_BRING_IN_WHITE);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 9 */
pixDisplayWithTitle(pix1, 600, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by sampling; no embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_SAMPLING,
L_BRING_IN_WHITE, 0, 0);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_SAMPLING,
L_BRING_IN_WHITE, 0, 0);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 10 */
pixDisplayWithTitle(pix1, 800, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by sampling; with embedding */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotate(pix1, 0.25, L_ROTATE_SAMPLING,
L_BRING_IN_WHITE, 250, 150);
pix3 = pixRotate(pix2, -0.35, L_ROTATE_SAMPLING,
L_BRING_IN_WHITE, 250, 150);
pix4 = pixRemoveBorderToSize(pix3, 250, 150);
pix5 = pixRemoveAlpha(pix4);
pixaAddPix(pixa, pix5, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
pixDestroy(&pix4);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 11 */
pixDisplayWithTitle(pix1, 1000, 400, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Rotation by area mapping at corner */
pixa = pixaCreate(n);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixRotateAMCorner(pix1, 0.25, L_BRING_IN_WHITE);
pix3 = pixRotateAMCorner(pix2, -0.35, L_BRING_IN_WHITE);
pix4 = pixRemoveAlpha(pix3);
pixaAddPix(pixa, pix4, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 12 */
pixDisplayWithTitle(pix1, 0, 800, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
#endif
#if DO_ALL
/* Affine transform by interpolation */
pixa = pixaCreate(n);
vc = Generate3PtTransformVector();
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixAffine(pix1, vc, L_BRING_IN_WHITE);
/* pix2 = pixAffineSampled(pix1, vc, L_BRING_IN_WHITE); */
pix3 = pixRemoveAlpha(pix2);
pixaAddPix(pixa, pix3, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 13 */
pixDisplayWithTitle(pix1, 200, 800, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
lept_free(vc);
#endif
#if DO_ALL
/* Projective transform by sampling */
pixa = pixaCreate(n);
vc = Generate4PtTransformVector(PROJECTIVE);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixProjectiveSampled(pix1, vc, L_BRING_IN_WHITE);
pix3 = pixRemoveAlpha(pix2);
pixaAddPix(pixa, pix3, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 14 */
pixDisplayWithTitle(pix1, 400, 800, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
lept_free(vc);
#endif
#if DO_ALL
/* Projective transform by interpolation */
pixa = pixaCreate(n);
vc = Generate4PtTransformVector(PROJECTIVE);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixProjective(pix1, vc, L_BRING_IN_WHITE);
pix3 = pixRemoveAlpha(pix2);
pixaAddPix(pixa, pix3, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 15 */
pixDisplayWithTitle(pix1, 600, 800, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
lept_free(vc);
#endif
#if DO_ALL
/* Bilinear transform by interpolation */
pixa = pixaCreate(n);
vc = Generate4PtTransformVector(BILINEAR);
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixas, i, L_COPY);
pix2 = pixBilinear(pix1, vc, L_BRING_IN_WHITE);
pix3 = pixRemoveAlpha(pix2);
pixaAddPix(pixa, pix3, L_INSERT);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pix1 = pixaDisplayTiledInRows(pixa, 32, 1200, 1.0, 0, 25, 2);
regTestWritePixAndCheck(rp, pix1, IFF_PNG); /* 16 */
pixDisplayWithTitle(pix1, 800, 800, NULL, rp->display);
pixDestroy(&pix1);
pixaDestroy(&pixa);
lept_free(vc);
#endif
pixaDestroy(&pixas);
return regTestCleanup(rp);
}
