progs/util/readtex.c

   1 /* readtex.c */
   2
   3 /*
   4  * Read an SGI .rgb image file and generate a mipmap texture set.
   5  * Much of this code was borrowed from SGI's tk OpenGL toolkit.
   6  */
   7
   8
   9
  10 #include <GL/gl.h>
  11 #include <GL/glu.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include "readtex.h"
  16
  17
  18 #ifndef SEEK_SET
  19 #  define SEEK_SET 0
  20 #endif
  21
  22
  23 /*
  24 ** RGB Image Structure
  25 */
  26
  27 typedef struct _TK_RGBImageRec {
  28    GLint sizeX, sizeY;
  29    GLint components;
  30    unsigned char *data;
  31 } TK_RGBImageRec;
  32
  33
  34
  35 /******************************************************************************/
  36
  37 typedef struct _rawImageRec {
  38     unsigned short imagic;
  39     unsigned short type;
  40     unsigned short dim;
  41     unsigned short sizeX, sizeY, sizeZ;
  42     unsigned long min, max;
  43     unsigned long wasteBytes;
  44     char name[80];
  45     unsigned long colorMap;
  46     FILE *file;
  47     unsigned char *tmp, *tmpR, *tmpG, *tmpB, *tmpA;
  48     unsigned long rleEnd;
  49     GLuint *rowStart;
  50     GLint *rowSize;
  51 } rawImageRec;
  52
  53 /******************************************************************************/
  54
  55 static void ConvertShort(unsigned short *array, long length)
  56 {
  57    unsigned long b1, b2;
  58    unsigned char *ptr;
  59
  60    ptr = (unsigned char *)array;
  61    while (length--) {
  62       b1 = *ptr++;
  63       b2 = *ptr++;
  64       *array++ = (unsigned short) ((b1 << 8) | (b2));
  65    }
  66 }
  67
  68 static void ConvertLong(GLuint *array, long length)
  69 {
  70    unsigned long b1, b2, b3, b4;
  71    unsigned char *ptr;
  72
  73    ptr = (unsigned char *)array;
  74    while (length--) {
  75       b1 = *ptr++;
  76       b2 = *ptr++;
  77       b3 = *ptr++;
  78       b4 = *ptr++;
  79       *array++ = (b1 << 24) | (b2 << 16) | (b3 << 8) | (b4);
  80    }
  81 }
  82
  83 static rawImageRec *RawImageOpen(const char *fileName)
  84 {
  85    union {
  86       int testWord;
  87       char testByte[4];
  88    } endianTest;
  89    rawImageRec *raw;
  90    GLenum swapFlag;
  91    int x;
  92
  93    endianTest.testWord = 1;
  94    if (endianTest.testByte[0] == 1) {
  95       swapFlag = GL_TRUE;
  96    } else {
  97       swapFlag = GL_FALSE;
  98    }
  99
 100    raw = (rawImageRec *)calloc(1, sizeof(rawImageRec));
 101    if (raw == NULL) {
 102       fprintf(stderr, "Out of memory!\n");
 103       return NULL;
 104    }
 105    if ((raw->file = fopen(fileName, "rb")) == NULL) {
 106       perror(fileName);
 107       return NULL;
 108    }
 109
 110    fread(raw, 1, 12, raw->file);
 111
 112    if (swapFlag) {
 113       ConvertShort(&raw->imagic, 6);
 114    }
 115
 116    raw->tmp = (unsigned char *)malloc(raw->sizeX*256);
 117    raw->tmpR = (unsigned char *)malloc(raw->sizeX*256);
 118    raw->tmpG = (unsigned char *)malloc(raw->sizeX*256);
 119    raw->tmpB = (unsigned char *)malloc(raw->sizeX*256);
 120    if (raw->sizeZ==4) {
 121       raw->tmpA = (unsigned char *)malloc(raw->sizeX*256);
 122    }
 123    if (raw->tmp == NULL || raw->tmpR == NULL || raw->tmpG == NULL ||
 124        raw->tmpB == NULL) {
 125       fprintf(stderr, "Out of memory!\n");
 126       return NULL;
 127    }
 128
 129    if ((raw->type & 0xFF00) == 0x0100) {
 130       x = raw->sizeY * raw->sizeZ * sizeof(GLuint);
 131       raw->rowStart = (GLuint *)malloc(x);
 132       raw->rowSize = (GLint *)malloc(x);
 133       if (raw->rowStart == NULL || raw->rowSize == NULL) {
 134          fprintf(stderr, "Out of memory!\n");
 135          return NULL;
 136       }
 137       raw->rleEnd = 512 + (2 * x);
 138       fseek(raw->file, 512, SEEK_SET);
 139       fread(raw->rowStart, 1, x, raw->file);
 140       fread(raw->rowSize, 1, x, raw->file);
 141       if (swapFlag) {
 142          ConvertLong(raw->rowStart, (long) (x/sizeof(GLuint)));
 143          ConvertLong((GLuint *)raw->rowSize, (long) (x/sizeof(GLint)));
 144       }
 145    }
 146    return raw;
 147 }
 148
 149 static void RawImageClose(rawImageRec *raw)
 150 {
 151    fclose(raw->file);
 152    free(raw->tmp);
 153    free(raw->tmpR);
 154    free(raw->tmpG);
 155    free(raw->tmpB);
 156    if (raw->rowStart)
 157       free(raw->rowStart);
 158    if (raw->rowSize)
 159       free(raw->rowSize);
 160    if (raw->sizeZ>3) {
 161       free(raw->tmpA);
 162    }
 163    free(raw);
 164 }
 165
 166 static void RawImageGetRow(rawImageRec *raw, unsigned char *buf, int y, int z)
 167 {
 168    unsigned char *iPtr, *oPtr, pixel;
 169    int count, done = 0;
 170
 171    if ((raw->type & 0xFF00) == 0x0100) {
 172       fseek(raw->file, (long) raw->rowStart[y+z*raw->sizeY], SEEK_SET);
 173       fread(raw->tmp, 1, (unsigned int)raw->rowSize[y+z*raw->sizeY],
 174             raw->file);
 175
 176       iPtr = raw->tmp;
 177       oPtr = buf;
 178       while (!done) {
 179          pixel = *iPtr++;
 180          count = (int)(pixel & 0x7F);
 181          if (!count) {
 182                          done = 1;
 183             return;
 184          }
 185          if (pixel & 0x80) {
 186             while (count--) {
 187                *oPtr++ = *iPtr++;
 188             }
 189          } else {
 190             pixel = *iPtr++;
 191             while (count--) {
 192                *oPtr++ = pixel;
 193             }
 194          }
 195       }
 196    } else {
 197       fseek(raw->file, 512+(y*raw->sizeX)+(z*raw->sizeX*raw->sizeY),
 198             SEEK_SET);
 199       fread(buf, 1, raw->sizeX, raw->file);
 200    }
 201 }
 202
 203
 204 static void RawImageGetData(rawImageRec *raw, TK_RGBImageRec *final)
 205 {
 206    unsigned char *ptr;
 207    int i, j;
 208
 209    final->data = (unsigned char *)malloc((raw->sizeX+1)*(raw->sizeY+1)*4);
 210    if (final->data == NULL) {
 211       fprintf(stderr, "Out of memory!\n");
 212    }
 213
 214    ptr = final->data;
 215    for (i = 0; i < (int)(raw->sizeY); i++) {
 216       RawImageGetRow(raw, raw->tmpR, i, 0);
 217       RawImageGetRow(raw, raw->tmpG, i, 1);
 218       RawImageGetRow(raw, raw->tmpB, i, 2);
 219       if (raw->sizeZ>3) {
 220          RawImageGetRow(raw, raw->tmpA, i, 3);
 221       }
 222       for (j = 0; j < (int)(raw->sizeX); j++) {
 223          *ptr++ = *(raw->tmpR + j);
 224          *ptr++ = *(raw->tmpG + j);
 225          *ptr++ = *(raw->tmpB + j);
 226          if (raw->sizeZ>3) {
 227             *ptr++ = *(raw->tmpA + j);
 228          }
 229       }
 230    }
 231 }
 232
 233
 234 static TK_RGBImageRec *tkRGBImageLoad(const char *fileName)
 235 {
 236    rawImageRec *raw;
 237    TK_RGBImageRec *final;
 238
 239    raw = RawImageOpen(fileName);
 240    if (!raw) {
 241       fprintf(stderr, "File not found\n");
 242       return NULL;
 243    }
 244    final = (TK_RGBImageRec *)malloc(sizeof(TK_RGBImageRec));
 245    if (final == NULL) {
 246       fprintf(stderr, "Out of memory!\n");
 247       return NULL;
 248    }
 249    final->sizeX = raw->sizeX;
 250    final->sizeY = raw->sizeY;
 251    final->components = raw->sizeZ;
 252    RawImageGetData(raw, final);
 253    RawImageClose(raw);
 254    return final;
 255 }
 256
 257
 258 static void FreeImage( TK_RGBImageRec *image )
 259 {
 260    free(image->data);
 261    free(image);
 262 }
 263
 264
 265 /*
 266  * Load an SGI .rgb file and generate a set of 2-D mipmaps from it.
 267  * Input:  imageFile - name of .rgb to read
 268  *         intFormat - internal texture format to use, or number of components
 269  * Return:  GL_TRUE if success, GL_FALSE if error.
 270  */
 271 GLboolean LoadRGBMipmaps( const char *imageFile, GLint intFormat )
 272 {
 273    GLint w, h;
 274    return LoadRGBMipmaps2( imageFile, GL_TEXTURE_2D, intFormat, &w, &h );
 275 }
 276
 277
 278
 279 GLboolean LoadRGBMipmaps2( const char *imageFile, GLenum target,
 280                            GLint intFormat, GLint *width, GLint *height )
 281 {
 282    GLint error;
 283    GLenum format;
 284    TK_RGBImageRec *image;
 285
 286    image = tkRGBImageLoad( imageFile );
 287    if (!image) {
 288       return GL_FALSE;
 289    }
 290
 291    if (image->components==3) {
 292       format = GL_RGB;
 293    }
 294    else if (image->components==4) {
 295       format = GL_RGBA;
 296    }
 297    else {
 298       /* not implemented */
 299       fprintf(stderr,
 300               "Error in LoadRGBMipmaps %d-component images not implemented\n",
 301               image->components );
 302       return GL_FALSE;
 303    }
 304
 305    error = gluBuild2DMipmaps( target,
 306                               intFormat,
 307                               image->sizeX, image->sizeY,
 308                               format,
 309                               GL_UNSIGNED_BYTE,
 310                               image->data );
 311
 312    *width = image->sizeX;
 313    *height = image->sizeY;
 314
 315    FreeImage(image);
 316
 317    return error ? GL_FALSE : GL_TRUE;
 318 }
 319
 320
 321
 322 /*
 323  * Load an SGI .rgb file and return a pointer to the image data.
 324  * Input:  imageFile - name of .rgb to read
 325  * Output:  width - width of image
 326  *          height - height of image
 327  *          format - format of image (GL_RGB or GL_RGBA)
 328  * Return:  pointer to image data or NULL if error
 329  */
 330 GLubyte *LoadRGBImage( const char *imageFile, GLint *width, GLint *height,
 331                        GLenum *format )
 332 {
 333    TK_RGBImageRec *image;
 334    GLint bytes;
 335    GLubyte *buffer;
 336
 337    image = tkRGBImageLoad( imageFile );
 338    if (!image) {
 339       return NULL;
 340    }
 341
 342    if (image->components==3) {
 343       *format = GL_RGB;
 344    }
 345    else if (image->components==4) {
 346       *format = GL_RGBA;
 347    }
 348    else {
 349       /* not implemented */
 350       fprintf(stderr,
 351               "Error in LoadRGBImage %d-component images not implemented\n",
 352               image->components );
 353       return NULL;
 354    }
 355
 356    *width = image->sizeX;
 357    *height = image->sizeY;
 358
 359    bytes = image->sizeX * image->sizeY * image->components;
 360    buffer = (GLubyte *) malloc(bytes);
 361    if (!buffer)
 362       return NULL;
 363
 364    memcpy( (void *) buffer, (void *) image->data, bytes );
 365
 366    FreeImage(image);
 367
 368    return buffer;
 369 }
 370
 371 #define CLAMP( X, MIN, MAX )  ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
 372
 373
 374 static void ConvertRGBtoYUV(GLint w, GLint h, GLint texel_bytes,
 375                             const GLubyte *src,
 376                             GLushort *dest)
 377 {
 378    GLint i, j;
 379
 380    for (i = 0; i < h; i++) {
 381       for (j = 0; j < w; j++) {
 382          const GLfloat r = (src[0]) / 255.0;
 383          const GLfloat g = (src[1]) / 255.0;
 384          const GLfloat b = (src[2]) / 255.0;
 385          GLfloat y, cr, cb;
 386          GLint iy, icr, icb;
 387
 388          y  = r * 65.481 + g * 128.553 + b * 24.966 + 16;
 389          cb = r * -37.797 + g * -74.203 + b * 112.0 + 128;
 390          cr = r * 112.0 + g * -93.786 + b * -18.214 + 128;
 391          /*printf("%f %f %f -> %f %f %f\n", r, g, b, y, cb, cr);*/
 392          iy  = (GLint) CLAMP(y,  0, 254);
 393          icb = (GLint) CLAMP(cb, 0, 254);
 394          icr = (GLint) CLAMP(cr, 0, 254);
 395
 396          if (j & 1) {
 397             /* odd */
 398             *dest = (iy << 8) | icr;
 399          }
 400          else {
 401             /* even */
 402             *dest = (iy << 8) | icb;
 403          }
 404          dest++;
 405          src += texel_bytes;
 406       }
 407    }
 408 }
 409
 410
 411 /*
 412  * Load an SGI .rgb file and return a pointer to the image data, converted
 413  * to 422 yuv.
 414  *
 415  * Input:  imageFile - name of .rgb to read
 416  * Output:  width - width of image
 417  *          height - height of image
 418  * Return:  pointer to image data or NULL if error
 419  */
 420 GLushort *LoadYUVImage( const char *imageFile, GLint *width, GLint *height )
 421 {
 422    TK_RGBImageRec *image;
 423    GLushort *buffer;
 424
 425    image = tkRGBImageLoad( imageFile );
 426    if (!image) {
 427       return NULL;
 428    }
 429
 430    if (image->components != 3 && image->components !=4 ) {
 431       /* not implemented */
 432       fprintf(stderr,
 433               "Error in LoadYUVImage %d-component images not implemented\n",
 434               image->components );
 435       return NULL;
 436    }
 437
 438    *width = image->sizeX;
 439    *height = image->sizeY;
 440
 441    buffer = (GLushort *) malloc( image->sizeX * image->sizeY * 2 );
 442
 443    if (buffer)
 444       ConvertRGBtoYUV( image->sizeX,
 445                        image->sizeY,
 446                        image->components,
 447                        image->data,
 448                        buffer );
 449
 450
 451    FreeImage(image);
 452    return buffer;
 453 }
 454