[FFmpeg-cvslog] avcodec/libjxlenc: use reciprocol gamma for GAMMA22 and GAMMA28

[Leo Izen]

ffmpeg | branch: master | Leo Izen <leo.izen at gmail.com> | Tue Apr  4 10:16:21 2023 -0400| [1179bb703e35543e15401f05a4cc81cc389756ba] | committer: Leo Izen

avcodec/libjxlenc: use reciprocol gamma for GAMMA22 and GAMMA28

libjxl rejects JxlColorEncoding->gamma 2.2f or 2.8f and expects
1/2.2f or 1/2.8f, respectively.

Signed-off-by: Leo Izen <leo.izen at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1179bb703e35543e15401f05a4cc81cc389756ba
---

 libavcodec/libjxlenc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/libjxlenc.c b/libavcodec/libjxlenc.c
index 897452f575..d707f3a61b 100644
--- a/libavcodec/libjxlenc.c
+++ b/libavcodec/libjxlenc.c
@@ -335,11 +335,11 @@ static int libjxl_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFra
         break;
     case AVCOL_TRC_GAMMA22:
         jxl_color.transfer_function = JXL_TRANSFER_FUNCTION_GAMMA;
-        jxl_color.gamma = 2.2;
+        jxl_color.gamma = 1/2.2f;
         break;
     case AVCOL_TRC_GAMMA28:
         jxl_color.transfer_function = JXL_TRANSFER_FUNCTION_GAMMA;
-        jxl_color.gamma = 2.8;
+        jxl_color.gamma = 1/2.8f;
         break;
     default:
         if (pix_desc->flags & AV_PIX_FMT_FLAG_FLOAT) {