Slightly improve/correct description of wc3_pal_lookup

Originally committed as revision 18462 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Reimar Döffinger 2009-04-12 08:49:20 +00:00
parent b275500706
commit f28c4e756f

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@ -76,9 +76,9 @@ typedef struct Wc3DemuxContext {
* palette lookup table that does gamma correction
*
* can be calculated by this formula:
* for i between 0 and 252 inclusive:
* wc3_pal_lookup[i] = pow(i / 256.0, 0.8) * 256;
* values 253, 254 and 255 are all 0xFD
* for i between 0 and 251 inclusive:
* wc3_pal_lookup[i] = round(pow(i / 256.0, 0.8) * 256);
* values 252, 253, 254 and 255 are all 0xFD
* calculating this at runtime should not cause any
* rounding issues, the maximum difference between
* the table values and the calculated doubles is