Python计算机视觉_增强现实

今天博主给大家展示一下python计算机视觉实现简单增强现实的代码
代码如下：

import math
import pickle
from pylab import *
from OpenGL.GL import * 
from OpenGL.GLU import * 
from OpenGL.GLUT import * 
import pygame, pygame.image 
from pygame.locals import *
from PCV.geometry import homography, camera
from PCV.localdescriptors import sift

def cube_points(c, wid):
    """ Creates a list of points for plotting
        a cube with plot. (the first 5 points are
        the bottom square, some sides repeated). """
    p = []
    # bottom
    p.append([c[0]-wid, c[1]-wid, c[2]-wid])
    p.append([c[0]-wid, c[1]+wid, c[2]-wid])
    p.append([c[0]+wid, c[1]+wid, c[2]-wid])
    p.append([c[0]+wid, c[1]-wid, c[2]-wid])
    p.append([c[0]-wid, c[1]-wid, c[2]-wid]) #same as first to close plot
    
    # top
    p.append([c[0]-wid, c[1]-wid, c[2]+wid])
    p.append([c[0]-wid, c[1]+wid, c[2]+wid])
    p.append([c[0]+wid, c[1]+wid, c[2]+wid])
    p.append([c[0]+wid, c[1]-wid, c[2]+wid])
    p.append([c[0]-wid, c[1]-wid, c[2]+wid]) #same as first to close plot
    
    # vertical sides
    p.append([c[0]-wid, c[1]-wid, c[2]+wid])
    p.append([c[0]-wid, c[1]+wid, c[2]+wid])
    p.append([c[0]-wid, c[1]+wid, c[2]-wid])
    p.append([c[0]+wid, c[1]+wid, c[2]-wid])
    p.append([c[0]+wid, c[1]+wid, c[2]+wid])
    p.append([c[0]+wid, c[1]-wid, c[2]+wid])
    p.append([c[0]+wid, c[1]-wid, c[2]-wid])
    
    return array(p).T
    
def my_calibration(sz):
    row, col = sz
    fx = 2555*col/2592
    fy = 2586*row/1936
    K = diag([fx, fy, 1])
    K[0, 2] = 0.5*col
    K[1, 2] = 0.5*row
    return K

def set_projection_from_camera(K): 
	glMatrixMode(GL_PROJECTION) 
	glLoadIdentity()
	fx = K[0,0] 
	fy = K[1,1] 
	fovy = 2*math.atan(0.5*height/fy)*180/math.pi 
	aspect = (width*fy)/(height*fx)
	near = 0.1 
	far = 100.0
	gluPerspective(fovy,aspect,near,far) 
	glViewport(0,0,width,height)

def set_modelview_from_camera(Rt): 
	glMatrixMode(GL_MODELVIEW) 
	glLoadIdentity()
	Rx = np.array([[1,0,0],[0,0,-1],[0,1,0]])
	R = Rt[:,:3] 
	U,S,V = np.linalg.svd(R) 
	R = np.dot(U,V) 
	R[0,:] = -R[0,:]
	t = Rt[:,3]
	M = np.eye(4) 
	M[:3,:3] = np.dot(R,Rx) 
	M[:3,3] = t
	M = M.T
	m = M.flatten()
	glLoadMatrixf(m)

def draw_background(imname):
	bg_image = pygame.image.load(imname).convert() 
	bg_data = pygame.image.tostring(bg_image,"RGBX",1)
	glMatrixMode(GL_MODELVIEW) 
	glLoadIdentity()

	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
	glEnable(GL_TEXTURE_2D) 
	glBindTexture(GL_TEXTURE_2D,glGenTextures(1)) 
	glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,width,height,0,GL_RGBA,GL_UNSIGNED_BYTE,bg_data) 
	glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST) 
	glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST)
	glBegin(GL_QUADS) 
	glTexCoord2f(0.0,0.0); glVertex3f(-1.0,-1.0,-1.0) 
	glTexCoord2f(1.0,0.0); glVertex3f( 1.0,-1.0,-1.0) 
	glTexCoord2f(1.0,1.0); glVertex3f( 1.0, 1.0,-1.0) 
	glTexCoord2f(0.0,1.0); glVertex3f(-1.0, 1.0,-1.0) 
	glEnd()
	glDeleteTextures(1)


def draw_teapot(size):
	glEnable(GL_LIGHTING) 
	glEnable(GL_LIGHT0) 
	glEnable(GL_DEPTH_TEST) 
	glClear(GL_DEPTH_BUFFER_BIT)
	glMaterialfv(GL_FRONT,GL_AMBIENT,[0,0,0,0]) 
	glMaterialfv(GL_FRONT,GL_DIFFUSE,[0.5,0.0,0.0,0.0]) 
	glMaterialfv(GL_FRONT,GL_SPECULAR,[0.7,0.6,0.6,0.0]) 
	glMaterialf(GL_FRONT,GL_SHININESS,0.25*128.0) 
	glutSolidTeapot(size)

width,height = 1000,747
def setup():
	pygame.init() 
	pygame.display.set_mode((width,height),OPENGL | DOUBLEBUF) 
	pygame.display.set_caption("OpenGL AR demo")    

# compute features
sift.process_image('book_frontal.JPG', 'im0.sift')
l0, d0 = sift.read_features_from_file('im0.sift')

sift.process_image('book_perspective.JPG', 'im1.sift')
l1, d1 = sift.read_features_from_file('im1.sift')

# match features and estimate homography
matches = sift.match_twosided(d0, d1)
ndx = matches.nonzero()[0]
fp = homography.make_homog(l0[ndx, :2].T)
ndx2 = [int(matches[i]) for i in ndx]
tp = homography.make_homog(l1[ndx2, :2].T)

model = homography.RansacModel()
H, inliers = homography.H_from_ransac(fp, tp, model)

K = my_calibration((747, 1000))
cam1 = camera.Camera(hstack((K, dot(K, array([[0], [0], [-1]])))))
box = cube_points([0, 0, 0.1], 0.1)
box_cam1 = cam1.project(homography.make_homog(box[:, :5]))
box_trans = homography.normalize(dot(H,box_cam1))
cam2 = camera.Camera(dot(H, cam1.P))
A = dot(linalg.inv(K), cam2.P[:, :3])
A = array([A[:, 0], A[:, 1], cross(A[:, 0], A[:, 1])]).T
cam2.P[:, :3] = dot(K, A)

Rt=dot(linalg.inv(K),cam2.P)
 
setup() 
draw_background("book_perspective.bmp") 
set_projection_from_camera(K) 
set_modelview_from_camera(Rt)
draw_teapot(0.05)

pygame.display.flip()
while True: 
	for event in pygame.event.get():
		if event.type==pygame.QUIT:
			sys.exit()

结果展示：

后期博主会继续添加一些更nb的例子，谢谢阅读！