[FFmpeg-devel] [PATCH] swscale/ops: fix ff_sws_pixel_type_to_uint (PR #20891)

[cancername via ffmpeg-devel <ffmpeg-devel@ffmpeg.org>]

PR #20891 opened by cancername
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20891
Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20891.patch

ff_sws_pixel_type_size uses size in bytes, not bits, but ff_sws_pixel_type_to_uint assumes size in bits. ff_sws_pixel_type_to_uint is never called anywhere, so this went unnoticed.


>From 6c6c9065ba40f2255defe0bf4692e5552c3e511f Mon Sep 17 00:00:00 2001
From: cancername <notcancername@protonmail.com>
Date: Tue, 11 Nov 2025 05:46:08 +0100
Subject: [PATCH 1/2] swscale/ops: fix ff_sws_pixel_type_to_uint

ff_sws_pixel_type_size uses size in bytes, not bits, but
ff_sws_pixel_type_to_uint assumes size in
bits. ff_sws_pixel_type_to_uint is never called anywhere, so this went
unnoticed.
---
 libswscale/ops.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/libswscale/ops.c b/libswscale/ops.c
index 21aeb16931..2d22c4a5fa 100644
--- a/libswscale/ops.c
+++ b/libswscale/ops.c
@@ -99,9 +99,9 @@ SwsPixelType ff_sws_pixel_type_to_uint(SwsPixelType type)
         return type;
 
     switch (ff_sws_pixel_type_size(type)) {
-    case 8:  return SWS_PIXEL_U8;
-    case 16: return SWS_PIXEL_U16;
-    case 32: return SWS_PIXEL_U32;
+    case 1: return SWS_PIXEL_U8;
+    case 2: return SWS_PIXEL_U16;
+    case 4: return SWS_PIXEL_U32;
     }
 
     av_unreachable("Invalid pixel type!");
-- 
2.49.1


>From 309b98f9330097590520a1294439f78023bbde40 Mon Sep 17 00:00:00 2001
From: cancername <notcancername@protonmail.com>
Date: Tue, 11 Nov 2025 05:46:18 +0100
Subject: [PATCH 2/2] swscale/ops: document that ff_sws_pixel_type_size uses
 bytes

---
 libswscale/ops.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libswscale/ops.h b/libswscale/ops.h
index 8f26ee832e..069fa6a0db 100644
--- a/libswscale/ops.h
+++ b/libswscale/ops.h
@@ -37,6 +37,9 @@ typedef enum SwsPixelType {
 } SwsPixelType;
 
 const char *ff_sws_pixel_type_name(SwsPixelType type);
+/**
+ * Return the size of type in bytes.
+ */
 int ff_sws_pixel_type_size(SwsPixelType type) av_const;
 bool ff_sws_pixel_type_is_int(SwsPixelType type) av_const;
 SwsPixelType ff_sws_pixel_type_to_uint(SwsPixelType type) av_const;
-- 
2.49.1

_______________________________________________
ffmpeg-devel mailing list -- ffmpeg-devel@ffmpeg.org
To unsubscribe send an email to ffmpeg-devel-leave@ffmpeg.org