[FFmpeg-devel] [PATCH v2 19/32] avfilter/palettegen: switch to signed arithmetic
Clément Bœsch
u at pkh.me
Wed Dec 28 01:18:01 EET 2022
This prevents mixed sign arithmetic (typically because we have signed
color channel differences), which has nasty side effects in C.
---
libavfilter/vf_palettegen.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/libavfilter/vf_palettegen.c b/libavfilter/vf_palettegen.c
index b8db234fef..99e4512e52 100644
--- a/libavfilter/vf_palettegen.c
+++ b/libavfilter/vf_palettegen.c
@@ -34,14 +34,14 @@
/* Reference a color and how much it's used */
struct color_ref {
uint32_t color;
- uint64_t count;
+ int64_t count;
};
/* Store a range of colors */
struct range_box {
uint32_t color; // average color
int major_axis; // best axis candidate for cutting the box
- uint64_t weight; // sum of all the weights of the colors
+ int64_t weight; // sum of all the weights of the colors
int64_t cut_score; // how likely the box is to be cut down (higher implying more likely)
int start; // index in PaletteGenContext->refs
int len; // number of referenced colors
@@ -141,7 +141,7 @@ static void compute_box_stats(PaletteGenContext *s, struct range_box *box)
int64_t er2[3] = {0};
/* Compute average color */
- uint64_t sr = 0, sg = 0, sb = 0;
+ int64_t sr = 0, sg = 0, sb = 0;
box->weight = 0;
for (int i = box->start; i < box->start + box->len; i++) {
const struct color_ref *ref = s->refs[i];
@@ -314,7 +314,7 @@ static AVFrame *get_palette_frame(AVFilterContext *ctx)
while (box && box->len > 1) {
int i;
- uint64_t median, weight;
+ int64_t median, weight;
ff_dlog(ctx, "box #%02X [%6d..%-6d] (%6d) w:%-6"PRIu64" sort by %c (already sorted:%c) ",
box_id, box->start, box->start + box->len - 1, box->len, box->weight,
--
2.39.0
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