l_int32 main(int argc,
char **argv)
{
l_int32 size, i, rval, gval, bval, yval, uval, vval;
l_float32 *a[3], b[3];
L_BMF *bmf;
PIX *pixd;
PIXA *pixa;
/* Explore the range of rgb --> yuv transforms. All rgb
* values transform to a valid value of yuv, so when transforming
* back we get the same rgb values that we started with. */
pixa = pixaCreate(0);
bmf = bmfCreate("fonts", 6);
for (gval = 0; gval <= 255; gval += 20)
AddTransformsRGB(pixa, bmf, gval);
pixd = pixaDisplayTiledAndScaled(pixa, 32, 755, 1, 0, 20, 2);
pixDisplay(pixd, 100, 0);
pixWrite("/tmp/yuv1.png", pixd, IFF_PNG);
pixDestroy(&pixd);
pixaDestroy(&pixa);
/* Now start with all "valid" yuv values, not all of which are
* related to a valid rgb value. Our yuv --> rgb transform
* clips the rgb components to [0 ... 255], so when transforming
* back we get different values whenever the initial yuv
* value is out of the rgb gamut. */
pixa = pixaCreate(0);
for (yval = 16; yval <= 235; yval += 16)
AddTransformsYUV(pixa, bmf, yval);
pixd = pixaDisplayTiledAndScaled(pixa, 32, 755, 1, 0, 20, 2);
pixDisplay(pixd, 600, 0);
pixWrite("/tmp/yuv2.png", pixd, IFF_PNG);
pixDestroy(&pixd);
pixaDestroy(&pixa);
bmfDestroy(&bmf);
/* --------- Try out a special case by hand, and show that --------- *
* ------- the transform matrices we are using are inverses ---------*/
/* First, use our functions for the transform */
fprintf(stderr, "Start with: yval = 143, uval = 79, vval = 103\n");
convertYUVToRGB(143, 79, 103, &rval, &gval, &bval);
fprintf(stderr, " ==> rval = %d, gval = %d, bval = %d\n", rval, gval, bval);
convertRGBToYUV(rval, gval, bval, &yval, &uval, &vval);
fprintf(stderr, " ==> yval = %d, uval = %d, vval = %d\n", yval, uval, vval);
/* Next, convert yuv --> rbg by solving for rgb --> yuv transform.
* [ a00 a01 a02 ] r = b0 (y - 16)
* [ a10 a11 a12 ] * g = b1 (u - 128)
* [ a20 a21 a22 ] b = b2 (v - 128)
*/
b[0] = 143.0 - 16.0; /* y - 16 */
b[1] = 79.0 - 128.0; /* u - 128 */
b[2] = 103.0 - 128.0; /* v - 128 */
for (i = 0; i < 3; i++)
a[i] = (l_float32 *)lept_calloc(3, sizeof(l_float32));
a[0][0] = 65.738 / 256.0;
a[0][1] = 129.057 / 256.0;
a[0][2] = 25.064 / 256.0;
a[1][0] = -37.945 / 256.0;
a[1][1] = -74.494 / 256.0;
a[1][2] = 112.439 / 256.0;
a[2][0] = 112.439 / 256.0;
a[2][1] = -94.154 / 256.0;
a[2][2] = -18.285 / 256.0;
fprintf(stderr, "Here's the original matrix: yuv --> rgb:\n");
for (i = 0; i < 3; i++)
fprintf(stderr, " %7.3f %7.3f %7.3f\n", 256.0 * a[i][0],
256.0 * a[i][1], 256.0 * a[i][2]);
gaussjordan(a, b, 3);
fprintf(stderr, "\nInput (yuv) = (143,79,103); solve for rgb:\n"
"rval = %7.3f, gval = %7.3f, bval = %7.3f\n",
b[0], b[1], b[2]);
fprintf(stderr, "Here's the inverse matrix: rgb --> yuv:\n");
for (i = 0; i < 3; i++)
fprintf(stderr, " %7.3f %7.3f %7.3f\n", 256.0 * a[i][0],
256.0 * a[i][1], 256.0 * a[i][2]);
/* Now, convert back: rgb --> yuv;
* Do this by solving for yuv --> rgb transform.
* Use the b[] found previously (the rgb values), and
* the a[][] which now holds the rgb --> yuv transform. */
gaussjordan(a, b, 3);
fprintf(stderr, "\nInput rgb; solve for yuv:\n"
"yval = %7.3f, uval = %7.3f, vval = %7.3f\n",
b[0] + 16.0, b[1] + 128.0, b[2] + 128.0);
fprintf(stderr, "Inverting the matrix again: yuv --> rgb:\n");
for (i = 0; i < 3; i++)
fprintf(stderr, " %7.3f %7.3f %7.3f\n", 256.0 * a[i][0],
256.0 * a[i][1], 256.0 * a[i][2]);
for (i = 0; i < 3; i++) lept_free(a[i]);
return 0;
}
main(int argc,
char **argv)
{
char *filein, *fileout;
l_uint8 *array1, *array2, *dataout, *dataout2;
l_int32 i, blocksize;
size_t nbytes, nout, nout2;
BBUFFER *bb, *bb2;
FILE *fp;
static char mainName[] = "buffertest";
if (argc != 3)
exit(ERROR_INT(" Syntax: buffertest filein fileout", mainName, 1));
filein = argv[1];
fileout = argv[2];
if ((array1 = l_binaryRead(filein, &nbytes)) == NULL)
exit(ERROR_INT("array not made", mainName, 1));
fprintf(stderr, " Bytes read from file: %ld\n", nbytes);
/* Application of byte buffer ops: compress/decompress in memory */
#if 1
dataout = zlibCompress(array1, nbytes, &nout);
l_binaryWrite(fileout, "w", dataout, nout);
dataout2 = zlibUncompress(dataout, nout, &nout2);
l_binaryWrite("/tmp/junktest", "w", dataout2, nout2);
fprintf(stderr,
"nbytes in = %ld, nbytes comp = %ld, nbytes uncomp = %ld\n",
nbytes, nout, nout2);
lept_free(dataout);
lept_free(dataout2);
#endif
/* Low-level byte buffer read/write test */
#if 0
bb = bbufferCreate(array1, nbytes);
bbufferRead(bb, array1, nbytes);
array2 = (l_uint8 *)lept_calloc(2 * nbytes, sizeof(l_uint8));
fprintf(stderr, " Bytes initially in buffer: %d\n", bb->n);
blocksize = (2 * nbytes) / NBLOCKS;
for (i = 0; i <= NBLOCKS; i++) {
bbufferWrite(bb, array2, blocksize, &nout);
fprintf(stderr, " block %d: wrote %d bytes\n", i + 1, nout);
}
fprintf(stderr, " Bytes left in buffer: %d\n", bb->n);
bb2 = bbufferCreate(NULL, 0);
bbufferRead(bb2, array1, nbytes);
fp = lept_fopen(fileout, "wb");
bbufferWriteStream(bb2, fp, nbytes, &nout);
fprintf(stderr, " bytes written out to fileout: %d\n", nout);
bbufferDestroy(&bb);
bbufferDestroy(&bb2);
lept_free(array2);
#endif
lept_free(array1);
return 0;
}
