Difference between revisions of "Dali Compressed file format"

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m (add decompression code)
m (6 revisions imported)
 
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uint32 *ltab=malloc(size of long array);
 
uint32 *ltab=malloc(size of long array);
  
−
/* Written by Lonny Pursell - placed into the Public Domain 1/19/2017 */
+
uint8 *bmap=malloc(32000); /* st bitmap */
 +
 
 +
/* PureC example by Lonny Pursell - placed into the Public Domain 1/19/2017 */
 +
uint8 flag;
 +
uint16 i, index, offset;
 +
uint32 data;
 
flag = index = 0;
 
flag = index = 0;
 
for (i=0; i<=156; i=i+4) {
 
for (i=0; i<=156; i=i+4) {

Latest revision as of 00:51, 4 June 2018

Dali compressed    *.LPK (ST low resolution)
                   *.MPK (ST medium resolution)
                   *.HPK (ST high resolution)
        
Files do not seem to have any resolution or bit plane info stored in them. The file
extension seems to be the only way to determine the contents.
        
16 words    palette
?           size of byte array in bytes, stored as plain ASCII text + cr/lf
?           size of long array in bytes, stored as plain ASCII text + cr/lf
?           array of bytes
?           array of longs

?           image data:
Assuming the tables have been loaded into arrays:
uint8 *btab=malloc(size of byte array);
uint32 *ltab=malloc(size of long array);

uint8 *bmap=malloc(32000); /* st bitmap */

/* PureC example by Lonny Pursell - placed into the Public Domain 1/19/2017 */
uint8 flag;
uint16 i, index, offset;
uint32 data;
flag = index = 0;
for (i=0; i<=156; i=i+4) {
    for (offset=0; offset<=31840; offset=offset+160) {
        if (flag==0) {
            flag = btab[index];
            data = ltab[index];
            index++;
        }
        bmap[offset + i] = (data >> 24) & 0xFF;
        bmap[offset + i + 1] = (data >> 16) & 0xFF;
        bmap[offset + i + 2] = (data >> 8) & 0xFF;
        bmap[offset + i + 3] = data & 0xFF;
        flag--;
    }
}

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