[FFmpeg-devel] [PATCH 4/5] avfilter/af_astats: rework sample loops

Marton Balint cus at passwd.hu
Tue Mar 5 22:46:05 EET 2019


The channel loop is now the outer loop for both planar and interleaved. This is
needed by the next patch, and the speed difference is negligable if any.

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 libavfilter/af_astats.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/libavfilter/af_astats.c b/libavfilter/af_astats.c
index f45558909a..9915a7965e 100644
--- a/libavfilter/af_astats.c
+++ b/libavfilter/af_astats.c
@@ -410,17 +410,18 @@ static void set_metadata(AudioStatsContext *s, AVDictionary **metadata)
     for (int c = 0; c < channels; c++) {                                        \
         ChannelStats *p = &s->chstats[c];                                       \
         const type *src = (const type *)data[c];                                \
-        for (int i = 0; i < samples; i++, src++)                                \
+        const type * const srcend = src + samples;                              \
+        for (; src < srcend; src++)                                             \
             update_stat(s, p, double_sample, normalized_sample, int_sample);    \
     }
 
-#define UPDATE_STATS_I(type, double_sample, normalized_sample, int_sample)                    \
-    {                                                                                         \
-        const type *src = (const type *)data[0];                                              \
-        for (int i = 0; i < samples; i++) {                                                   \
-            for (int c = 0; c < channels; c++, src++)                                         \
-                update_stat(s, &s->chstats[c], double_sample, normalized_sample, int_sample); \
-        }                                                                                     \
+#define UPDATE_STATS_I(type, double_sample, normalized_sample, int_sample)      \
+    for (int c = 0; c < channels; c++) {                                        \
+        ChannelStats *p = &s->chstats[c];                                       \
+        const type *src = (const type *)data[0];                                \
+        const type * const srcend = src + samples * channels;                   \
+        for (src += c; src < srcend; src += channels)                           \
+            update_stat(s, p, double_sample, normalized_sample, int_sample);    \
     }
 
 #define UPDATE_STATS(planar, type, sample, normalizer_suffix, int_sample) \
-- 
2.16.4



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