diff mbox series

[FFmpeg-devel,2/3] avcodec/evc_parse: remove pow() and log2()

Message ID 20231012232759.5352-2-michael@niedermayer.cc
State New
Headers show
Series [FFmpeg-devel,1/3] avcodec/evc_ps: Check chroma_format_idc | expand

Checks

Context Check Description
andriy/make_x86 success Make finished
andriy/make_fate_x86 success Make fate finished

Commit Message

Michael Niedermayer Oct. 12, 2023, 11:27 p.m. UTC 
The use of float based functions is both unneeded and wrong due to unpredictable rounding

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/evc_parse.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c
index bd3a4416f2..255706ce61 100644
--- a/libavcodec/evc_parse.c
+++ b/libavcodec/evc_parse.c
@@ -172,7 +172,8 @@  int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh,
             poc->PicOrderCntVal = 0;
             poc->DocOffset = -1;
         } else {
-            int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length);
+            int SubGopLength = 1 << sps->log2_sub_gop_length;
+
             if (tid == 0) {
                 poc->PicOrderCntVal = poc->prevPicOrderCntVal + SubGopLength;
                 poc->DocOffset = 0;
@@ -187,15 +188,16 @@  int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh,
                     poc->prevPicOrderCntVal += SubGopLength;
                     ExpectedTemporalId = 0;
                 } else
-                    ExpectedTemporalId = 1 + (int)log2(poc->DocOffset);
+                    ExpectedTemporalId = 1 + av_log2(poc->DocOffset);
+
                 while (tid != ExpectedTemporalId) {
                     poc->DocOffset = (poc->DocOffset + 1) % SubGopLength;
                     if (poc->DocOffset == 0)
                         ExpectedTemporalId = 0;
                     else
-                        ExpectedTemporalId = 1 + (int)log2(poc->DocOffset);
+                        ExpectedTemporalId = 1 + av_log2(poc->DocOffset);
                 }
-                PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / (int)pow(2.0, tid) - 2));
+                PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / (1 << tid) - 2));
                 poc->PicOrderCntVal = poc->prevPicOrderCntVal + PocOffset;
             }
         }