From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.ffmpeg.org (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTPS id 4A12B4BB8A for ; Wed, 23 Jul 2025 13:57:52 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTP id 274F068D8D6; Wed, 23 Jul 2025 16:56:47 +0300 (EEST) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTP id 49AAB68D867 for ; Wed, 23 Jul 2025 16:56:33 +0300 (EEST) Received: from haasn.dev (unknown [10.30.1.1]) by haasn.dev (Postfix) with UTF8SMTP id B65DD483CD; Wed, 23 Jul 2025 15:56:28 +0200 (CEST) From: Niklas Haas To: ffmpeg-devel@ffmpeg.org Date: Wed, 23 Jul 2025 15:47:13 +0200 Message-ID: <20250723135626.1390296-11-ffmpeg@haasn.xyz> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250723135626.1390296-1-ffmpeg@haasn.xyz> References: <20250723135626.1390296-1-ffmpeg@haasn.xyz> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH v2 10/18] avcodec/jpegxl: parse and signal correct alpha mode X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Niklas Haas Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: From: Niklas Haas This header bit ("alpha_associated") was incorrectly ignored. --- libavcodec/jpegxl_parse.c | 7 +++++-- libavcodec/jpegxl_parse.h | 1 + libavcodec/jpegxl_parser.c | 5 +++++ 3 files changed, 11 insertions(+), 2 deletions(-) diff --git a/libavcodec/jpegxl_parse.c b/libavcodec/jpegxl_parse.c index 022eed322d..47b831e2b4 100644 --- a/libavcodec/jpegxl_parse.c +++ b/libavcodec/jpegxl_parse.c @@ -190,6 +190,7 @@ static void jpegxl_get_bit_depth(GetBitContext *gb, FFJXLMetadata *meta) static int jpegxl_read_extra_channel_info(GetBitContext *gb, FFJXLMetadata *meta, int validate) { int default_alpha = get_bits1(gb); + int alpha_associated = 0; uint32_t type, name_len = 0; if (!default_alpha) { @@ -213,7 +214,7 @@ static int jpegxl_read_extra_channel_info(GetBitContext *gb, FFJXLMetadata *meta skip_bits_long(gb, name_len); if (!default_alpha && type == JPEGXL_CT_ALPHA) - skip_bits1(gb); + alpha_associated = get_bits1(gb); if (type == JPEGXL_CT_SPOT_COLOR) skip_bits_long(gb, 16 * 4); @@ -221,8 +222,10 @@ static int jpegxl_read_extra_channel_info(GetBitContext *gb, FFJXLMetadata *meta if (type == JPEGXL_CT_CFA) jxl_u32(gb, 1, 0, 3, 19, 0, 2, 4, 8); - if (meta && type == JPEGXL_CT_ALPHA) + if (meta && type == JPEGXL_CT_ALPHA) { meta->have_alpha = 1; + meta->alpha_associated = alpha_associated; + } return 0; } diff --git a/libavcodec/jpegxl_parse.h b/libavcodec/jpegxl_parse.h index 0602f4d409..bb929ccee1 100644 --- a/libavcodec/jpegxl_parse.h +++ b/libavcodec/jpegxl_parse.h @@ -35,6 +35,7 @@ typedef struct FFJXLMetadata { uint32_t coded_height; int bit_depth; int have_alpha; + int alpha_associated; /* * offset, in bits, of the animation header * zero if not animated diff --git a/libavcodec/jpegxl_parser.c b/libavcodec/jpegxl_parser.c index 75acc53708..c13601f3d7 100644 --- a/libavcodec/jpegxl_parser.c +++ b/libavcodec/jpegxl_parser.c @@ -1074,6 +1074,11 @@ static void populate_fields(AVCodecParserContext *s, AVCodecContext *avctx, cons else s->format = meta->have_alpha ? AV_PIX_FMT_RGBAF32 : AV_PIX_FMT_RGBF32; } + + if (meta->have_alpha) { + avctx->alpha_mode |= meta->alpha_associated ? AVALPHA_MODE_PREMULTIPLIED + : AVALPHA_MODE_STRAIGHT; + } } static int skip_icc_profile(void *avctx, JXLParseContext *ctx, GetBitContext *gb) -- 2.50.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".