diff options
author | Keith Whitwell <[email protected]> | 2003-05-20 09:54:58 +0000 |
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committer | Keith Whitwell <[email protected]> | 2003-05-20 09:54:58 +0000 |
commit | 27358a24a0113a62492923abe35e8660ed7335ef (patch) | |
tree | 474f45986d53e0829312ac99db7dc78634d4a84d /progs/util/readtex.c | |
parent | eea72ff722975d91bc2293a403bb43d69e5858d0 (diff) |
move LoadYUVImage into readtex.c
Diffstat (limited to 'progs/util/readtex.c')
-rw-r--r-- | progs/util/readtex.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/progs/util/readtex.c b/progs/util/readtex.c index d9a5dc78f5c..406498202b2 100644 --- a/progs/util/readtex.c +++ b/progs/util/readtex.c @@ -365,3 +365,88 @@ GLubyte *LoadRGBImage( const char *imageFile, GLint *width, GLint *height, return buffer; } +#define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) ) + + +static void ConvertRGBtoYUV(GLint w, GLint h, GLint texel_bytes, + const GLubyte *src, + GLushort *dest) +{ + GLint i, j; + + for (i = 0; i < h; i++) { + for (j = 0; j < w; j++) { + const GLfloat r = (src[0]) / 255.0; + const GLfloat g = (src[1]) / 255.0; + const GLfloat b = (src[2]) / 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++; + src += texel_bytes; + } + } +} + + +/* + * Load an SGI .rgb file and return a pointer to the image data, converted + * to 422 yuv. + * + * Input: imageFile - name of .rgb to read + * Output: width - width of image + * height - height of image + * Return: pointer to image data or NULL if error + */ +GLushort *LoadYUVImage( const char *imageFile, GLint *width, GLint *height ) +{ + TK_RGBImageRec *image; + GLint bytes; + GLushort *buffer; + + image = tkRGBImageLoad( imageFile ); + if (!image) { + return NULL; + } + + if (image->components != 3 && image->components !=4 ) { + /* not implemented */ + fprintf(stderr, + "Error in LoadYUVImage %d-component images not implemented\n", + image->components ); + return NULL; + } + + *width = image->sizeX; + *height = image->sizeY; + + buffer = (GLushort *) malloc( image->sizeX * image->sizeY * 2 ); + + if (buffer) + ConvertRGBtoYUV( image->sizeX, + image->sizeY, + image->components, + image->data, + buffer ); + + + FreeImage(image); + return buffer; +} + |