aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMichael Niedermayer <michaelni@gmx.at>2007-03-25 13:41:14 +0000
committerMichael Niedermayer <michaelni@gmx.at>2007-03-25 13:41:14 +0000
commit62ef8925c5bbc7b74d3263838f31e8d02bdb9376 (patch)
treeef7b1c15d35043cb692082013a25566b47966f77
parentb6661510459da787b6f04871b89d09256c809e1d (diff)
downloadffmpeg-62ef8925c5bbc7b74d3263838f31e8d02bdb9376.tar.gz
simplify
Originally committed as revision 8509 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r--libavcodec/lzw.c14
1 files changed, 4 insertions, 10 deletions
diff --git a/libavcodec/lzw.c b/libavcodec/lzw.c
index 11a6bf0578..cb12eb8573 100644
--- a/libavcodec/lzw.c
+++ b/libavcodec/lzw.c
@@ -55,7 +55,7 @@ struct LZWState {
int end_code;
int newcodes; ///< First available code
int top_slot; ///< Highest code for current size
- int top_slot2; ///< Highest possible code for current size (<=top_slot)
+ int extra_slot;
int slot; ///< Last read code
int fc, oc;
uint8_t *sp;
@@ -158,10 +158,10 @@ int ff_lzw_decode_init(LZWState *p, int csize, uint8_t *buf, int buf_size, int m
s->mode = mode;
switch(s->mode){
case FF_LZW_GIF:
- s->top_slot2 = s->top_slot;
+ s->extra_slot= 0;
break;
case FF_LZW_TIFF:
- s->top_slot2 = s->top_slot - 1;
+ s->extra_slot= 1;
break;
default:
return -1;
@@ -208,9 +208,6 @@ int ff_lzw_decode(LZWState *p, uint8_t *buf, int len){
s->curmask = mask[s->cursize];
s->slot = s->newcodes;
s->top_slot = 1 << s->cursize;
- s->top_slot2 = s->top_slot;
- if(s->mode == FF_LZW_TIFF)
- s->top_slot2--;
while ((c = lzw_get_code(s)) == s->clear_code);
if (c == s->end_code) {
s->end_code = -1;
@@ -239,12 +236,9 @@ int ff_lzw_decode(LZWState *p, uint8_t *buf, int len){
s->prefix[s->slot++] = oc;
oc = c;
}
- if (s->slot >= s->top_slot2) {
+ if (s->slot >= s->top_slot - s->extra_slot) {
if (s->cursize < LZW_MAXBITS) {
s->top_slot <<= 1;
- s->top_slot2 = s->top_slot;
- if(s->mode == FF_LZW_TIFF)
- s->top_slot2--;
s->curmask = mask[++s->cursize];
}
}