ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Wed Jun 4 20:27:46 2025 +0200| [730ffc5d35e0a2d48644da6f6880859bbbebd1c5] | committer: Andreas Rheinhardt
avfilter/vf_overlay: Hoist calculations out of loop
Also use const where appropriate.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=730ffc5d35e0a2d48644da6f6880859bbbebd1c5
---
libavfilter/vf_overlay.c | 36 ++++++++++++++----------------------
1 file changed, 14 insertions(+), 22 deletions(-)
diff --git a/libavfilter/vf_overlay.c b/libavfilter/vf_overlay.c
index 17fe8e47c9..d77fe87c05 100644
--- a/libavfilter/vf_overlay.c
+++ b/libavfilter/vf_overlay.c
@@ -470,16 +470,13 @@ static av_always_inline void blend_plane_##depth##_##nbits##bits(AVFilterContext
int dst_hp = AV_CEIL_RSHIFT(dst_h, vsub); \
int yp = y>>vsub; \
int xp = x>>hsub; \
- int jmax, j, k, kmax; \
- int slice_start, slice_end; \
const T max = (1 << nbits) - 1; \
const T mid = (1 << (nbits - 1)); \
\
- j = FFMAX(-yp, 0); \
- jmax = FFMIN3(-yp + dst_hp, FFMIN(src_hp, dst_hp), yp + src_hp); \
- \
- slice_start = j + (jmax * jobnr) / nb_jobs; \
- slice_end = j + (jmax * (jobnr+1)) / nb_jobs; \
+ const int jmin = FFMAX(-yp, 0), jmax = FFMIN3(-yp + dst_hp, FFMIN(src_hp, dst_hp), yp + src_hp); \
+ const int kmin = FFMAX(-xp, 0), kmax = FFMIN(-xp + dst_wp, src_wp); \
+ const int slice_start = jmin + (jmax * jobnr) / nb_jobs; \
+ const int slice_end = jmin + (jmax * (jobnr + 1)) / nb_jobs; \
\
const uint8_t *sp = src->data[i] + (slice_start) * src->linesize[i]; \
uint8_t *dp = dst->data[dst_plane] \
@@ -488,13 +485,12 @@ static av_always_inline void blend_plane_##depth##_##nbits##bits(AVFilterContext
const uint8_t *ap = src->data[3] + (slice_start << vsub) * src->linesize[3]; \
const uint8_t *dap = main_has_alpha ? dst->data[3] + ((yp + slice_start) << vsub) * dst->linesize[3] : NULL; \
\
- for (j = slice_start; j < slice_end; j++) { \
- k = FFMAX(-xp, 0); \
+ for (int j = slice_start; j < slice_end; ++j) { \
+ int k = kmin; \
const T *s = (const T *)sp + k; \
const T *a = (const T *)ap + (k << hsub); \
const T *da = main_has_alpha ? (T *)dap + ((xp + k) << hsub) : NULL; \
T *d = (T *)(dp + (xp + k) * dst_step); \
- kmax = FFMIN(-xp + dst_wp, src_wp); \
\
if (nbits == 8 && ((vsub && j+1 < src_hp) || !vsub) && octx->blend_row[i]) { \
int c = octx->blend_row[i]((uint8_t*)d, (uint8_t*)da, (uint8_t*)s, \
@@ -585,25 +581,21 @@ static inline void alpha_composite_##depth##_##nbits##bits(const AVFrame *src, c
int jobnr, int nb_jobs) \
{ \
T alpha; /* the amount of overlay to blend on to main */ \
- int i, imax, j, jmax; \
- int slice_start, slice_end; \
const T max = (1 << nbits) - 1; \
\
- imax = FFMIN3(-y + dst_h, FFMIN(src_h, dst_h), y + src_h); \
- i = FFMAX(-y, 0); \
- \
- slice_start = i + (imax * jobnr) / nb_jobs; \
- slice_end = i + ((imax * (jobnr+1)) / nb_jobs); \
+ const int imin = FFMAX(-y, 0), imax = FFMIN3(-y + dst_h, FFMIN(src_h, dst_h), y + src_h); \
+ const int jmin = FFMAX(-x, 0), jmax = FFMIN(-x + dst_w, src_w); \
+ const int slice_start = imin + ( imax * jobnr) / nb_jobs; \
+ const int slice_end = imin + ((imax * (jobnr + 1)) / nb_jobs); \
\
const uint8_t *sa = src->data[3] + (slice_start) * src->linesize[3]; \
uint8_t *da = dst->data[3] + (y + slice_start) * dst->linesize[3]; \
\
- for (i = slice_start; i < slice_end; i++) { \
- j = FFMAX(-x, 0); \
- const T *s = (const T *)sa + j; \
- T *d = (T *)da + x + j; \
+ for (int i = slice_start; i < slice_end; ++i) { \
+ const T *s = (const T *)sa + jmin; \
+ T *d = (T *)da + x + jmin; \
\
- for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) { \
+ for (int j = jmin; j < jmax; ++j) { \
alpha = *s; \
if (alpha != 0 && alpha != max) { \
uint8_t alpha_d = *d; \