[FFmpeg-devel] [PATCH 37/39] avcodec/mpeg12enc: Also inline chroma subsampling

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Sat Dec 25 08:06:12 EET 2021


ff_mpeg1_encode_mb() contains two inlined calls to
mpeg1_encode_mb_internal(); these calls are supposed
to inline the properties depending upon the color space
used. Yet inlining vertical chroma subsampling (which
allows to remove complete branches and blocks depending
upon them) has been forgotten.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
Looking at this code makes me wonder whether inlining was ever
worth it here.

 libavcodec/mpeg12enc.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/libavcodec/mpeg12enc.c b/libavcodec/mpeg12enc.c
index 3692494713..1437ac421c 100644
--- a/libavcodec/mpeg12enc.c
+++ b/libavcodec/mpeg12enc.c
@@ -773,7 +773,8 @@ next_coef:
 static av_always_inline void mpeg1_encode_mb_internal(MpegEncContext *s,
                                                       int16_t block[8][64],
                                                       int motion_x, int motion_y,
-                                                      int mb_block_count)
+                                                      int mb_block_count,
+                                                      int chroma_y_shift)
 {
     int i, cbp;
     const int mb_x     = s->mb_x;
@@ -918,7 +919,7 @@ static av_always_inline void mpeg1_encode_mb_internal(MpegEncContext *s,
                 s->mv_bits += get_bits_diff(s);
             }
             if (cbp) {
-                if (s->chroma_y_shift) {
+                if (chroma_y_shift) {
                     put_bits(&s->pb,
                              ff_mpeg12_mbPatTable[cbp][1],
                              ff_mpeg12_mbPatTable[cbp][0]);
@@ -1025,7 +1026,7 @@ static av_always_inline void mpeg1_encode_mb_internal(MpegEncContext *s,
             }
             s->mv_bits += get_bits_diff(s);
             if (cbp) {
-                if (s->chroma_y_shift) {
+                if (chroma_y_shift) {
                     put_bits(&s->pb,
                              ff_mpeg12_mbPatTable[cbp][1],
                              ff_mpeg12_mbPatTable[cbp][0]);
@@ -1052,9 +1053,9 @@ void ff_mpeg1_encode_mb(MpegEncContext *s, int16_t block[8][64],
                         int motion_x, int motion_y)
 {
     if (s->chroma_format == CHROMA_420)
-        mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 6);
+        mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 6, 1);
     else
-        mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 8);
+        mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 8, 0);
 }
 
 static av_cold void mpeg12_encode_init_static(void)
-- 
2.32.0



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