1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
/*
* Test the GL_NV_texture_rectangle and GL_MESA_ycrcb_texture extensions.
*
* Brian Paul 13 September 2002
*/
#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define GL_GLEXT_PROTOTYPES
#include <GL/glut.h>
#include "readtex.c" /* I know, this is a hack. */
#define TEXTURE_FILE "../images/girl.rgb"
static GLfloat Xrot = 0, Yrot = 0, Zrot = 0;
static GLint ImgWidth, ImgHeight;
static GLenum ImgFormat;
static GLubyte *Image = NULL;
static GLushort *ImageYUV = NULL;
static void DrawObject(void)
{
glBegin(GL_QUADS);
glTexCoord2f(0, 0);
glVertex2f(-1.0, -1.0);
glTexCoord2f(ImgWidth, 0);
glVertex2f(1.0, -1.0);
glTexCoord2f(ImgWidth, ImgHeight);
glVertex2f(1.0, 1.0);
glTexCoord2f(0, ImgHeight);
glVertex2f(-1.0, 1.0);
glEnd();
}
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT );
glPushMatrix();
glRotatef(Xrot, 1.0, 0.0, 0.0);
glRotatef(Yrot, 0.0, 1.0, 0.0);
glRotatef(Zrot, 0.0, 0.0, 1.0);
DrawObject();
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -15.0 );
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void SpecialKey( int key, int x, int y )
{
float step = 3.0;
(void) x;
(void) y;
switch (key) {
case GLUT_KEY_UP:
Xrot += step;
break;
case GLUT_KEY_DOWN:
Xrot -= step;
break;
case GLUT_KEY_LEFT:
Yrot += step;
break;
case GLUT_KEY_RIGHT:
Yrot -= step;
break;
}
glutPostRedisplay();
}
#define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
static void ConvertRGBtoYUV(GLint w, GLint h, const GLubyte *src,
GLushort *dest)
{
GLint i, j;
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++) {
const GLfloat r = (*src++) / 255.0;
const GLfloat g = (*src++) / 255.0;
const GLfloat b = (*src++) / 255.0;
GLfloat y, cr, cb;
GLint iy, icr, icb;
y = r * 65.481 + g * 128.553 + b * 24.966 + 16;
cb = r * -37.797 + g * -74.203 + b * 112.0 + 128;
cr = r * 112.0 + g * -93.786 + b * -18.214 + 128;
/*printf("%f %f %f -> %f %f %f\n", r, g, b, y, cb, cr);*/
iy = (GLint) CLAMP(y, 0, 254);
icb = (GLint) CLAMP(cb, 0, 254);
icr = (GLint) CLAMP(cr, 0, 254);
if (j & 1) {
/* odd */
*dest = (iy << 8) | icr;
}
else {
/* even */
*dest = (iy << 8) | icb;
}
dest++;
}
}
}
static void Init( int argc, char *argv[] )
{
GLuint texObj = 100;
const char *file;
if (!glutExtensionSupported("GL_NV_texture_rectangle")) {
printf("Sorry, GL_NV_texture_rectangle is required\n");
exit(0);
}
if (!glutExtensionSupported("GL_MESA_ycbcr_texture")) {
printf("Sorry, GL_MESA_ycbcr_texture is required\n");
exit(0);
}
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glBindTexture(GL_TEXTURE_RECTANGLE_NV, texObj);
#ifdef LINEAR_FILTER
/* linear filtering looks much nicer but is much slower for Mesa */
glTexParameteri(GL_TEXTURE_RECTANGLE_NV, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_RECTANGLE_NV, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
#else
glTexParameteri(GL_TEXTURE_RECTANGLE_NV, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_RECTANGLE_NV, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
#endif
if (argc > 1)
file = argv[1];
else
file = TEXTURE_FILE;
Image = LoadRGBImage(file, &ImgWidth, &ImgHeight, &ImgFormat);
if (!Image) {
printf("Couldn't read %s\n", TEXTURE_FILE);
exit(0);
}
#if 0
glTexImage2D(GL_TEXTURE_RECTANGLE_NV, 0,
GL_RGB, ImgWidth, ImgHeight, 0,
ImgFormat, GL_UNSIGNED_BYTE, Image);
#else
ImageYUV = (GLushort *) malloc(ImgWidth * ImgHeight * sizeof(GLushort));
ConvertRGBtoYUV(ImgWidth, ImgHeight, Image, ImageYUV);
glTexImage2D(GL_TEXTURE_RECTANGLE_NV, 0,
GL_YCBCR_MESA, ImgWidth, ImgHeight, 0,
GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_MESA, ImageYUV);
assert(glGetError() == GL_NO_ERROR);
glTexSubImage2D(GL_TEXTURE_RECTANGLE_NV, 0,
0, 0, ImgWidth, ImgHeight,
GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_MESA, ImageYUV);
assert(glGetError() == GL_NO_ERROR);
#endif
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glEnable(GL_TEXTURE_RECTANGLE_NV);
glShadeModel(GL_FLAT);
glClearColor(0.3, 0.3, 0.4, 1.0);
if (argc > 1 && strcmp(argv[1], "-info")==0) {
printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
}
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowSize( 300, 300 );
glutInitWindowPosition( 0, 0 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
glutCreateWindow(argv[0] );
Init( argc, argv );
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutDisplayFunc( Display );
glutMainLoop();
return 0;
}
|
