Fix loading of indexed .bmp files

D1173 by @rdb

Support for 1,2,4 bit images
This commit is contained in:
Campbell Barton
2015-03-11 21:32:00 +11:00
parent 064fa4baae
commit 4b3641ec99

View File

@@ -105,7 +105,7 @@ static int checkbmp(unsigned char *mem)
if (u >= sizeof(BMPINFOHEADER)) {
if (bmi.biCompression == 0) {
u = LITTLE_SHORT(bmi.biBitCount);
if (u >= 8) {
if (u > 0 && u <= 32) {
ret_val = 1;
}
}
@@ -136,10 +136,15 @@ struct ImBuf *imb_bmp_decode(unsigned char *mem, size_t size, int flags, char co
colorspace_set_default_role(colorspace, IM_MAX_SPACE, COLOR_ROLE_DEFAULT_BYTE);
bmp = mem + LITTLE_LONG(*(int*)(mem + 10));
if (CHECK_HEADER_FIELD_BMP(mem)) {
/* skip fileheader */
mem += BMP_FILEHEADER_SIZE;
}
else {
return 0;
}
/* for systems where an int needs to be 4 bytes aligned */
memcpy(&bmi, mem, sizeof(bmi));
@@ -173,29 +178,43 @@ struct ImBuf *imb_bmp_decode(unsigned char *mem, size_t size, int flags, char co
}
else {
ibuf = IMB_allocImBuf(x, y, ibuf_depth, IB_rect);
bmp = mem + skip;
rect = (unsigned char *) ibuf->rect;
if (depth == 8) {
const int x_pad = (4 - (x % 4)) % 4;
const char (*palette)[4] = (void *)bmp;
bmp += bmi.biClrUsed * 4;
if (depth <= 8) {
const int rowsize = (depth * x + 31) / 32 * 4;
const char (*palette)[4] = (void *)(mem + skip);
const int startmask = ((1 << depth) - 1) << 8;
for (i = y; i > 0; i--) {
int index;
int bitoffs = 8;
int bitmask = startmask;
int nbytes = 0;
const char *pcol;
if (top_to_bottom) {
rect = (unsigned char *) &ibuf->rect[(i - 1) * x];
}
for (j = x; j > 0; j--) {
const char *pcol = palette[bmp[0]];
bitoffs -= depth;
bitmask >>= depth;
index = (bmp[0] & bitmask) >> bitoffs;
pcol = palette[index];
/* intentionally BGR -> RGB */
rect[0] = pcol[2];
rect[1] = pcol[1];
rect[2] = pcol[0];
rect[3] = 255;
rect += 4; bmp += 1;
rect += 4;
if (bitoffs == 0) {
/* Advance to the next byte */
bitoffs = 8;
bitmask = startmask;
nbytes += 1;
bmp += 1;
}
/* rows are padded to multiples of 4 */
bmp += x_pad;
}
/* Advance to the next row */
bmp += (rowsize - nbytes);
}
}
else if (depth == 16) {