diff options
Diffstat (limited to 'audio/chmap.c')
| -rw-r--r-- | audio/chmap.c | 22 |
1 files changed, 8 insertions, 14 deletions
diff --git a/audio/chmap.c b/audio/chmap.c index 4f76eedd59..4fd43e3bc7 100644 --- a/audio/chmap.c +++ b/audio/chmap.c @@ -395,26 +395,20 @@ void mp_chmap_get_reorder(int src[MP_NUM_CHANNELS], const struct mp_chmap *from, assert(src[n] < 0 || (to->speaker[n] == from->speaker[src[n]])); } -// Return channels that are only in a. -// Performs the difference between a and b, and store it in diff. If b has -// channels that do not appear in a, those will not appear in the difference. -// To get to those the argument ordering in the function call has to be -// inverted. For the same reason, the diff with a superset will return no -// speakers. -void mp_chmap_diff(const struct mp_chmap *a, const struct mp_chmap *b, - struct mp_chmap *diff) +static int popcount64(uint64_t bits) { - uint64_t a_mask = mp_chmap_to_lavc_unchecked(a); - uint64_t b_mask = mp_chmap_to_lavc_unchecked(b); - mp_chmap_from_lavc(diff, (a_mask ^ b_mask) & a_mask); + int r = 0; + for (int n = 0; n < 64; n++) + r += !!(bits & (1ULL << n)); + return r; } // Return the number of channels only in a. int mp_chmap_diffn(const struct mp_chmap *a, const struct mp_chmap *b) { - struct mp_chmap diff; - mp_chmap_diff(a, b, &diff); - return diff.num; + uint64_t a_mask = mp_chmap_to_lavc_unchecked(a); + uint64_t b_mask = mp_chmap_to_lavc_unchecked(b); + return popcount64((a_mask ^ b_mask) & a_mask); } // Returns something like "fl-fr-fc". If there's a standard layout in lavc |