From c4e9556cf54609b9182dfb1766d3e2c43299a9d6 Mon Sep 17 00:00:00 2001 From: Connor Worley Date: Thu, 8 Feb 2024 11:07:08 -0800 Subject: [PATCH] lavc/texturedsp: fix premult2straight inversion This function should convert premultiplied alpha to straight, but does the opposite. Signed-off-by: Connor Worley --- libavcodec/texturedsp.c | 9 ++++++--- tests/ref/fate/dds-dxt2 | 2 +- tests/ref/fate/dds-dxt4 | 2 +- 3 files changed, 8 insertions(+), 5 deletions(-) diff --git a/libavcodec/texturedsp.c b/libavcodec/texturedsp.c index 5fb79937da..721bfc17f5 100644 --- a/libavcodec/texturedsp.c +++ b/libavcodec/texturedsp.c @@ -175,9 +175,12 @@ static av_always_inline void premult2straight(uint8_t *src) int b = src[2]; int a = src[3]; /* unchanged */ - src[0] = (uint8_t) r * a / 255; - src[1] = (uint8_t) g * a / 255; - src[2] = (uint8_t) b * a / 255; + if (a == 0) + return; + + src[0] = (uint8_t) FFMIN(r * 255 / a, 255); + src[1] = (uint8_t) FFMIN(g * 255 / a, 255); + src[2] = (uint8_t) FFMIN(b * 255 / a, 255); } /** diff --git a/tests/ref/fate/dds-dxt2 b/tests/ref/fate/dds-dxt2 index b5bdfbadc3..1744ef41f6 100644 --- a/tests/ref/fate/dds-dxt2 +++ b/tests/ref/fate/dds-dxt2 @@ -3,4 +3,4 @@ #codec_id 0: rawvideo #dimensions 0: 64x64 #sar 0: 0/1 -0, 0, 0, 1, 16384, 0x11cebeb0 +0, 0, 0, 1, 16384, 0xd7f7241b diff --git a/tests/ref/fate/dds-dxt4 b/tests/ref/fate/dds-dxt4 index 136dfd8006..f22878da56 100644 --- a/tests/ref/fate/dds-dxt4 +++ b/tests/ref/fate/dds-dxt4 @@ -3,4 +3,4 @@ #codec_id 0: rawvideo #dimensions 0: 64x64 #sar 0: 0/1 -0, 0, 0, 1, 16384, 0x31aaacd6 +0, 0, 0, 1, 16384, 0xf18d4216