[NUT-devel] [nut]: r236 - trunk/libnut/demuxer.c
ods15
subversion at mplayerhq.hu
Sat Nov 18 14:31:03 CET 2006
Author: ods15
Date: Sat Nov 18 14:31:03 2006
New Revision: 236
Modified:
trunk/libnut/demuxer.c
Log:
clean up some of binary_search
Modified: trunk/libnut/demuxer.c
==============================================================================
--- trunk/libnut/demuxer.c (original)
+++ trunk/libnut/demuxer.c Sat Nov 18 14:31:03 2006
@@ -977,17 +977,28 @@
return 0;
}
+#define INTERPOLATE_WEIGHT (19./20)
+static off_t seek_interpolate(int max_distance, double time_pos, off_t lo, off_t hi, double lo_pd, double hi_pd) {
+ off_t guess;
+ if (hi - lo < max_distance) guess = lo + 16;
+ else { // linear interpolation
+ double a = (double)(hi - lo) / (hi_pd - lo_pd);
+ guess = lo + a * (time_pos - lo_pd);
+ guess = guess * INTERPOLATE_WEIGHT + (lo+hi)/2. * (1 - INTERPOLATE_WEIGHT);
+ if (hi - guess < max_distance) guess = hi - max_distance; //(lo + hi)/2;
+ }
+ if (guess < lo + 16) guess = lo + 16;
+ return guess;
+}
+
static int binary_search_syncpoint(nut_context_t * nut, double time_pos, off_t * start, off_t * end, syncpoint_t * stopper) {
int i, err = 0;
syncpoint_t s;
- off_t hi, lo;
- uint64_t hip, lop;
+ off_t fake_hi;
uint64_t timebases[nut->timebase_count];
syncpoint_list_t * sl = &nut->syncpoints;
int a = 0;
-
for (i = 0; i < nut->timebase_count; i++) timebases[i] = (uint64_t)(time_pos / nut->tb[i].nom * nut->tb[i].den);
-
assert(sl->len); // it is impossible for the first syncpoint to not have been read
// find last syncpoint if it's not already found
@@ -1023,60 +1034,40 @@
i--;
- lo = sl->s[i].pos;
- lop = sl->s[i].pts;
- hi = sl->s[i+1].pos;
- hip = sl->s[i+1].pts;
- if (nut->seek_status) hi = nut->seek_status;
-
- while (!sl->s[i].seen_next) {
- // start binary search between sl->s[i].pos (lo) to sl->s[i+1].pos (hi) ...
- off_t guess;
- int res, tmp;
- double hi_pd = TO_DOUBLE_PTS(hip);
- double lo_pd = TO_DOUBLE_PTS(lop);
+#define LO (sl->s[i])
+#define HI (sl->s[i+1])
+ fake_hi = nut->seek_status ? nut->seek_status : HI.pos;
+
+ while (!LO.seen_next) {
+ // start binary search between LO (sl->s[i].pos) to HI (sl->s[i+1].pos) ...
+ off_t guess = seek_interpolate(nut->max_distance*2, time_pos, LO.pos, fake_hi, TO_DOUBLE_PTS(LO.pts), TO_DOUBLE_PTS(HI.pts));
+
+ fprintf(stderr, "\n%d [ (%d,%.3f) .. (%d,%.3f) .. (%d,%.3f) ] ", i, (int)LO.pos, TO_DOUBLE_PTS(LO.pts), (int)guess, time_pos,
+ (int)fake_hi, TO_DOUBLE_PTS(HI.pts));
a++;
- if (hi - lo < nut->max_distance*2) guess = lo + 16;
- else { // linear interpolation
-#define INTERPOLATE_WEIGHT (19./20)
- double a = (double)(hi - lo) / (hi_pd - lo_pd);
- guess = lo + a * (time_pos - lo_pd);
- guess = guess * INTERPOLATE_WEIGHT + (lo+hi)/2 * (1 - INTERPOLATE_WEIGHT);
- if (hi - guess < nut->max_distance*2) guess = hi - nut->max_distance*2; //(lo + hi)/2;
- }
- if (guess < lo + 8) guess = lo + 16;
- fprintf(stderr, "\n%d [ (%d,%.3f) .. (%d,%.3f) .. (%d,%.3f) ] ", i, (int)lo, lo_pd, (int)guess, time_pos, (int)hi, hi_pd);
+
if (!nut->seek_status) seek_buf(nut->i, guess, SEEK_SET);
- nut->seek_status = hi; // so we know where to continue off...
- CHECK(find_syncpoint(nut, 0, &s, hi));
+ nut->seek_status = fake_hi; // so we know where to continue off...
+ CHECK(find_syncpoint(nut, 0, &s, fake_hi));
nut->seek_status = 0;
- if (s.seen_next == 1 || s.pos >= hi) { // we got back to 'hi'
- // either we scanned everything from lo to hi, or we keep trying
- if (guess <= lo + 16) sl->s[i].seen_next = 1; // we are done!
- else hi = guess;
+ if (s.seen_next == 1 || s.pos >= fake_hi) { // we got back to 'HI'
+ // either we scanned everything from LO to HI, or we keep trying
+ if (guess <= LO.pos + 16) LO.seen_next = 1; // we are done!
+ else fake_hi = guess;
continue;
}
- res = (s.pts / nut->timebase_count > timebases[s.pts % nut->timebase_count]);
- if (res) {
- hi = s.pos;
- hip = s.pts;
- } else {
- lo = s.pos;
- lop = s.pts;
- }
- CHECK(add_syncpoint(nut, s, NULL, NULL, &tmp)); // unconditionally even without syncpoint cache
- if (!res) i = tmp;
+ CHECK(add_syncpoint(nut, s, NULL, NULL, timebases[s.pts%nut->timebase_count] < s.pts/nut->timebase_count ? NULL : &i));
+ fake_hi = HI.pos;
}
fprintf(stderr, "\n[ (%d,%d) .. %d .. (%d,%d) ] => %d (%d seeks) %d\n",
- (int)lo, (int)lop, (int)timebases[0], (int)hi, (int)hip, (int)(lo - sl->s[i].back_ptr), a, sl->s[i].back_ptr);
- // at this point, s[i].pts < P < s[i+1].pts, and s[i].flag is set
- // meaning, there are no more syncpoints between s[i] to s[i+1]
- *start = sl->s[i].pos - sl->s[i].back_ptr;
- *end = sl->s[i+1].pos;
- *stopper = sl->s[i+1];
+ (int)LO.pos, (int)LO.pts, (int)timebases[0], (int)fake_hi, (int)HI.pts, (int)(LO.pos - LO.back_ptr), a, LO.back_ptr);
+ // at this point, s[i].pts < P < s[i+1].pts, and s[i].seen_next is set
+ *start = LO.pos - LO.back_ptr;
+ *end = HI.pos;
+ *stopper = HI;
err_out:
if (err == NUT_ERR_EAGAIN) nut->i->buf_ptr = nut->i->buf;
return err;
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