static void _ccv_read_bmp_fd(FILE* in, ccv_dense_matrix_t** x, int type)
{
fseek(in, 10, SEEK_SET);
int offset;
(void) fread(&offset, 4, 1, in);
int size;
(void) fread(&size, 4, 1, in);
int width = 0, height = 0, bpp = 0, rle_code = 0, clrused = 0;
if (size >= 36)
{
(void) fread(&width, 4, 1, in);
(void) fread(&height, 4, 1, in);
(void) fread(&bpp, 4, 1, in);
bpp = bpp >> 16;
(void) fread(&rle_code, 4, 1, in);
fseek(in, 12, SEEK_CUR);
(void) fread(&clrused, 4, 1, in);
fseek(in, size - 36, SEEK_CUR);
/* only support 24-bit bmp */
} else if (size == 12) {
(void) fread(&width, 4, 1, in);
(void) fread(&height, 4, 1, in);
(void) fread(&bpp, 4, 1, in);
bpp = bpp >> 16;
/* TODO: not finished */
}
if (width == 0 || height == 0 || bpp == 0)
return;
ccv_dense_matrix_t* im = *x;
if (im == 0)
*x = im = ccv_dense_matrix_new(height, width, (type) ? type : CCV_8U | ((bpp > 8) ? CCV_C3 : CCV_C1), 0, 0);
fseek(in, offset, SEEK_SET);
int i, j;
unsigned char* ptr = im->data.u8 + (im->rows - 1) * im->step;
if ((bpp == 8 && CCV_GET_CHANNEL(im->type) == CCV_C1) || (bpp == 24 && CCV_GET_CHANNEL(im->type) == CCV_C3))
{
if (CCV_GET_CHANNEL(im->type) == CCV_C1)
{
for (i = 0; i < im->rows; i++)
{
(void) fread(ptr, 1, im->step, in);
ptr -= im->step;
}
} else {
for (i = 0; i < im->rows; i++)
{
(void) fread(ptr, 1, im->step, in);
for (j = 0; j < im->cols * 3; j += 3)
{
unsigned char t = ptr[j];
ptr[j] = ptr[j + 2];
ptr[j + 2] = t;
}
ptr -= im->step;
}
}
} else {
if (bpp == 24 && CCV_GET_CHANNEL(im->type) == CCV_C1)
{
int bufstep = (im->cols * 3 + 3) & -4;
unsigned char* buffer = (unsigned char*)alloca(bufstep);
for (i = 0; i < im->rows; i++)
{
(void) fread(buffer, 1, bufstep, in);
unsigned char* rgb = buffer;
unsigned char* g = ptr;
for(j = 0; j < im->cols; j++, rgb += 3, g++)
*g = (unsigned char)((rgb[2] * 6969 + rgb[1] * 23434 + rgb[0] * 2365) >> 15);
ptr -= im->step;
}
} else if (bpp == 8 && CCV_GET_CHANNEL(im->type) == CCV_C3) {
int bufstep = (im->cols + 3) & -4;
unsigned char* buffer = (unsigned char*)alloca(bufstep);
for (i = 0; i < im->rows; i++)
{
(void) fread(buffer, 1, bufstep, in);
unsigned char* g = buffer;
unsigned char* rgb = ptr;
for(j = 0; j < im->cols; j++, rgb += 3, g++)
rgb[2] = rgb[1] = rgb[0] = *g;
ptr -= im->step;
}
}
}
}