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[79.124.17.100]) by mx.google.com with ESMTP id d9-20020a170906040900b006f458fb419bsi2026769eja.219.2022.06.01.11.06.16; Wed, 01 Jun 2022 11:06:16 -0700 (PDT) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@google.com header.s=20210112 header.b=ZCEdIM0b; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id A116F68B7AB; Wed, 1 Jun 2022 21:06:07 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 7B0FA68B766 for ; Wed, 1 Jun 2022 21:06:01 +0300 (EEST) Received: by mail-pj1-f73.google.com with SMTP id s18-20020a17090aa11200b001d92f7609e8so1470946pjp.3 for ; Wed, 01 Jun 2022 11:06:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=T41PWj0BH4rnb7f9OoruQ1O5aAWzmKyhmPA/qq1Pda8=; b=ZCEdIM0baCHIpK1m/kHaf1FqKVXq0DTTVsW2CfUJ5dO7XSryQCfT2CfgpqpGGjTNHq LyaT/qdjalvrW21FNODOydquanU0cV9cHLC9Y7DovDiH6tzXZYiew5V+t0cFUxztxNby P71Yphq4qxVoO5bAOBvJg3kGy692aolpZgdDiZ5quyIm0FAs6dWNoeyWc9SKuSl9OXml jq0wGBm6Zu42VIJEREpX30tq+MF7N2d4lntQogdeeFM7LDhCSFvQzlFuSpvR8jbvroK3 rxB+ngyOdr3RvWzct4LehZ05JSkzFd1JUwEOhv/IHx2k7NDaa+vRUr96P5isc+fOPD65 c0ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=T41PWj0BH4rnb7f9OoruQ1O5aAWzmKyhmPA/qq1Pda8=; b=WaXI09PhWjVQd95S0w01flexTkLyIAwmFTvMOuD2naOQZgkJA8dTw2m5uDPEzxsgIH QZujjd/5TkhbJxd60WtcO2Cbr7iRs17VQ3abrTycAEMZE7hSRtVYNtqBGIjxdY88ZO7F aSNM8Rzd/8ryJiep2Ar9aB1cNeUwKbsVGXTedvY0m11FNYqLQtxNH6zI9vjIQK0OMKnu BTOeInxlVuOPWlcBhholAmFWirbIdLbg4pdOCqS6VPpoFIzz+ujKplhOLXZ68tktfF5m 56WwSuGcidJMTiDqeDErm9QQwwx5e+LXuXoADOiNkkNV0b1+oZBQ+e2fCHEooFQvNSIn 65qg== X-Gm-Message-State: AOAM532ESZPQ9bspjyYwZW1bllhMs2c8A4hbtZtH4mQCM0SIeUy2w3Bs IZwk7xzf05DnAdRbhBYyCskTU6b0ws5Op/vFPZzvviKWiHP4HbVgcL9AUzZkU0i+1rFoCH0BWBL FH1eLwodgRziBHk4nwCFtf8Za/yNd6rGZFYyiYznv5Fq6Nq8ymTj03luf3I0Pkebx2TJa X-Received: from vigneshv3.mtv.corp.google.com ([2620:0:1000:2511:c15a:291d:d112:ec10]) (user=vigneshv job=sendgmr) by 2002:a17:90a:6941:b0:1e2:f37a:f889 with SMTP id j1-20020a17090a694100b001e2f37af889mr19094537pjm.160.1654106759597; Wed, 01 Jun 2022 11:05:59 -0700 (PDT) Date: Wed, 1 Jun 2022 11:05:56 -0700 In-Reply-To: Message-Id: <20220601180556.949526-1-vigneshv@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.36.1.255.ge46751e96f-goog From: Vignesh Venkatasubramanian To: ffmpeg-devel@ffmpeg.org Subject: [FFmpeg-devel] [PATCH] avformat/movenc: Support alpha channel for AVIF 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: Vignesh Venkatasubramanian Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" X-TUID: XUqg1EsyiqZ6 AVIF specification allows for alpha channel as an auxiliary item (in case of still images) or as an auxiliary track (in case of animated images). Add support for both of these. The AVIF muxer will take exactly two streams (when alpha is present) as input (first one being the YUV planes and the second one being the alpha plane). The input has to come from two different images (one of it color and the other one being alpha), or it can come from a single file source with the alpha channel extracted using the "alphaextract" filter. Example using alphaextract: ffmpeg -i rgba.png -filter_complex "[0:v]alphaextract[a]" -map 0 -map "[a]" -still-picture 1 avif_with_alpha.avif Example using two sources (first source can be in any pixel format and the second source has to be in monochrome grey pixel format): ffmpeg -i color.avif -i grey.avif -map 0 -map 1 -c copy avif_with_alpha.avif The generated files pass the compliance checks in Compliance Warden: https://github.com/gpac/ComplianceWarden libavif (the reference avif library) is able to decode the files generated using this patch. They also play back properly (with transparent background) in: 1) Chrome 2) Firefox (only still AVIF, no animation support) Signed-off-by: Vignesh Venkatasubramanian --- libavformat/movenc.c | 188 +++++++++++++++++++++++++++++-------------- libavformat/movenc.h | 4 +- 2 files changed, 130 insertions(+), 62 deletions(-) diff --git a/libavformat/movenc.c b/libavformat/movenc.c index de971f94e8..02eb4d0e9a 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -2852,7 +2852,7 @@ static int mov_write_hdlr_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *tra hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0"; if (track->par->codec_type == AVMEDIA_TYPE_VIDEO) { if (track->mode == MODE_AVIF) { - hdlr_type = "pict"; + hdlr_type = (track == &mov->tracks[0]) ? "pict" : "auxv"; descr = "PictureHandler"; } else { hdlr_type = "vide"; @@ -2940,57 +2940,83 @@ static int mov_write_iloc_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatConte avio_wb32(pb, 0); /* Version & flags */ avio_w8(pb, (4 << 4) + 4); /* offset_size(4) and length_size(4) */ avio_w8(pb, 0); /* base_offset_size(4) and reserved(4) */ - avio_wb16(pb, 1); /* item_count */ + avio_wb16(pb, s->nb_streams); /* item_count */ - avio_wb16(pb, 1); /* item_id */ - avio_wb16(pb, 0); /* data_reference_index */ - avio_wb16(pb, 1); /* extent_count */ - mov->avif_extent_pos = avio_tell(pb); - avio_wb32(pb, 0); /* extent_offset (written later) */ - // For animated AVIF, we simply write the first packet's size. - avio_wb32(pb, mov->avif_extent_length); /* extent_length */ + for (int i = 0; i < s->nb_streams; i++) { + avio_wb16(pb, i + 1); /* item_id */ + avio_wb16(pb, 0); /* data_reference_index */ + avio_wb16(pb, 1); /* extent_count */ + mov->avif_extent_pos[i] = avio_tell(pb); + avio_wb32(pb, 0); /* extent_offset (written later) */ + // For animated AVIF, we simply write the first packet's size. + avio_wb32(pb, mov->avif_extent_length[i]); /* extent_length */ + } return update_size(pb, pos); } static int mov_write_iinf_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s) { - int64_t infe_pos; int64_t iinf_pos = avio_tell(pb); avio_wb32(pb, 0); /* size */ ffio_wfourcc(pb, "iinf"); avio_wb32(pb, 0); /* Version & flags */ - avio_wb16(pb, 1); /* entry_count */ + avio_wb16(pb, s->nb_streams); /* entry_count */ - infe_pos = avio_tell(pb); - avio_wb32(pb, 0); /* size */ - ffio_wfourcc(pb, "infe"); - avio_w8(pb, 0x2); /* Version */ - avio_wb24(pb, 0); /* flags */ - avio_wb16(pb, 1); /* item_id */ - avio_wb16(pb, 0); /* item_protection_index */ - avio_write(pb, "av01", 4); /* item_type */ - avio_write(pb, "Color\0", 6); /* item_name */ - update_size(pb, infe_pos); + for (int i = 0; i < s->nb_streams; i++) { + int64_t infe_pos = avio_tell(pb); + avio_wb32(pb, 0); /* size */ + ffio_wfourcc(pb, "infe"); + avio_w8(pb, 0x2); /* Version */ + avio_wb24(pb, 0); /* flags */ + avio_wb16(pb, i + 1); /* item_id */ + avio_wb16(pb, 0); /* item_protection_index */ + avio_write(pb, "av01", 4); /* item_type */ + avio_write(pb, !i ? "Color\0" : "Alpha\0", 6); /* item_name */ + update_size(pb, infe_pos); + } return update_size(pb, iinf_pos); } -static int mov_write_ispe_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s) + +static int mov_write_iref_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s) +{ + int64_t auxl_pos; + int64_t iref_pos = avio_tell(pb); + avio_wb32(pb, 0); /* size */ + ffio_wfourcc(pb, "iref"); + avio_wb32(pb, 0); /* Version & flags */ + + auxl_pos = avio_tell(pb); + avio_wb32(pb, 0); /* size */ + ffio_wfourcc(pb, "auxl"); + avio_wb16(pb, 2); /* from_item_ID */ + avio_wb16(pb, 1); /* reference_count */ + avio_wb16(pb, 1); /* to_item_ID */ + update_size(pb, auxl_pos); + + return update_size(pb, iref_pos); +} + +static int mov_write_ispe_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s, + int stream_index) { int64_t pos = avio_tell(pb); avio_wb32(pb, 0); /* size */ ffio_wfourcc(pb, "ispe"); avio_wb32(pb, 0); /* Version & flags */ - avio_wb32(pb, s->streams[0]->codecpar->width); /* image_width */ - avio_wb32(pb, s->streams[0]->codecpar->height); /* image_height */ + avio_wb32(pb, s->streams[stream_index]->codecpar->width); /* image_width */ + avio_wb32(pb, s->streams[stream_index]->codecpar->height); /* image_height */ return update_size(pb, pos); } -static int mov_write_pixi_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s) +static int mov_write_pixi_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s, + int stream_index) { int64_t pos = avio_tell(pb); - const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(s->streams[0]->codecpar->format); + const AVPixFmtDescriptor *pixdesc = + av_pix_fmt_desc_get(s->streams[stream_index]->codecpar->format); avio_wb32(pb, 0); /* size */ ffio_wfourcc(pb, "pixi"); avio_wb32(pb, 0); /* Version & flags */ @@ -3001,15 +3027,30 @@ static int mov_write_pixi_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatConte return update_size(pb, pos); } +static int mov_write_auxC_tag(AVIOContext *pb) +{ + int64_t pos = avio_tell(pb); + avio_wb32(pb, 0); /* size */ + ffio_wfourcc(pb, "auxC"); + avio_wb32(pb, 0); /* Version & flags */ + avio_write(pb, "urn:mpeg:mpegB:cicp:systems:auxiliary:alpha\0", 44); + return update_size(pb, pos); +} + static int mov_write_ipco_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s) { int64_t pos = avio_tell(pb); avio_wb32(pb, 0); /* size */ ffio_wfourcc(pb, "ipco"); - mov_write_ispe_tag(pb, mov, s); - mov_write_pixi_tag(pb, mov, s); - mov_write_av1c_tag(pb, &mov->tracks[0]); - mov_write_colr_tag(pb, &mov->tracks[0], 0); + for (int i = 0; i < s->nb_streams; i++) { + mov_write_ispe_tag(pb, mov, s, i); + mov_write_pixi_tag(pb, mov, s, i); + mov_write_av1c_tag(pb, &mov->tracks[i]); + if (!i) + mov_write_colr_tag(pb, &mov->tracks[0], 0); + else + mov_write_auxC_tag(pb); + } return update_size(pb, pos); } @@ -3019,18 +3060,21 @@ static int mov_write_ipma_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatConte avio_wb32(pb, 0); /* size */ ffio_wfourcc(pb, "ipma"); avio_wb32(pb, 0); /* Version & flags */ - avio_wb32(pb, 1); /* entry_count */ - avio_wb16(pb, 1); /* item_ID */ - avio_w8(pb, 4); /* association_count */ - - // ispe association. - avio_w8(pb, 1); /* essential and property_index */ - // pixi association. - avio_w8(pb, 2); /* essential and property_index */ - // av1C association. - avio_w8(pb, 0x80 | 3); /* essential and property_index */ - // colr association. - avio_w8(pb, 4); /* essential and property_index */ + avio_wb32(pb, s->nb_streams); /* entry_count */ + + for (int i = 0, index = 1; i < s->nb_streams; i++) { + avio_wb16(pb, i + 1); /* item_ID */ + avio_w8(pb, 4); /* association_count */ + + // ispe association. + avio_w8(pb, index++); /* essential and property_index */ + // pixi association. + avio_w8(pb, index++); /* essential and property_index */ + // av1C association. + avio_w8(pb, 0x80 | index++); /* essential and property_index */ + // colr/auxC association. + avio_w8(pb, index++); /* essential and property_index */ + } return update_size(pb, pos); } @@ -4112,6 +4156,8 @@ static int mov_write_meta_tag(AVIOContext *pb, MOVMuxContext *mov, mov_write_pitm_tag(pb, 1); mov_write_iloc_tag(pb, mov, s); mov_write_iinf_tag(pb, mov, s); + if (s->nb_streams > 1) + mov_write_iref_tag(pb, mov, s); mov_write_iprp_tag(pb, mov, s); } else { /* iTunes metadata tag */ @@ -6040,8 +6086,8 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt) avio_write(pb, reformatted_data, size); } else { size = ff_av1_filter_obus(pb, pkt->data, pkt->size); - if (trk->mode == MODE_AVIF && !mov->avif_extent_length) { - mov->avif_extent_length = size; + if (trk->mode == MODE_AVIF && !mov->avif_extent_length[pkt->stream_index]) { + mov->avif_extent_length[pkt->stream_index] = size; } } @@ -6872,16 +6918,26 @@ static int mov_init(AVFormatContext *s) return AVERROR(EINVAL); } - /* AVIF output must have exactly one video stream */ + /* AVIF output must have at most two video streams (one for YUV and one for + * alpha). */ if (mov->mode == MODE_AVIF) { - if (s->nb_streams > 1) { - av_log(s, AV_LOG_ERROR, "AVIF output requires exactly one stream\n"); + if (s->nb_streams > 2) { + av_log(s, AV_LOG_ERROR, "AVIF output requires exactly one or two streams\n"); return AVERROR(EINVAL); } - if (s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO) { - av_log(s, AV_LOG_ERROR, "AVIF output requires one video stream\n"); + if (s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO && + (s->nb_streams > 1 && s->streams[1]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO)) { + av_log(s, AV_LOG_ERROR, "AVIF output supports only video streams\n"); return AVERROR(EINVAL); } + if (s->nb_streams > 1) { + const AVPixFmtDescriptor *pixdesc = + av_pix_fmt_desc_get(s->streams[1]->codecpar->format); + if (pixdesc->nb_components != 1) { + av_log(s, AV_LOG_ERROR, "Second stream for AVIF (alpha) output must have exactly one plane\n"); + return AVERROR(EINVAL); + } + } s->streams[0]->disposition |= AV_DISPOSITION_DEFAULT; } @@ -7543,18 +7599,25 @@ static int avif_write_trailer(AVFormatContext *s) { AVIOContext *pb = s->pb; MOVMuxContext *mov = s->priv_data; - int64_t pos_backup, mdat_pos; + int64_t pos_backup, extent_offsets[2]; uint8_t *buf; - int buf_size, moov_size; + int buf_size, moov_size, i; if (mov->moov_written) return 0; mov->is_animated_avif = s->streams[0]->nb_frames > 1; + if (mov->is_animated_avif && s->nb_streams > 1) { + // For animated avif with alpha channel, we need to write a tref tag + // with type "auxl". + mov->tracks[1].tref_tag = MKTAG('a', 'u', 'x', 'l'); + mov->tracks[1].tref_id = 1; + } mov_write_identification(pb, s); mov_write_meta_tag(pb, mov, s); moov_size = get_moov_size(s); - mov->tracks[0].data_offset = avio_tell(pb) + moov_size + 8; + for (i = 0; i < s->nb_streams; i++) + mov->tracks[i].data_offset = avio_tell(pb) + moov_size + 8; if (mov->is_animated_avif) { int ret; @@ -7565,19 +7628,24 @@ static int avif_write_trailer(AVFormatContext *s) buf_size = avio_get_dyn_buf(mov->mdat_buf, &buf); avio_wb32(pb, buf_size + 8); ffio_wfourcc(pb, "mdat"); - mdat_pos = avio_tell(pb); - if (mdat_pos != (uint32_t)mdat_pos) { - av_log(s, AV_LOG_ERROR, "mdat offset does not fit in 32 bits\n"); - return AVERROR_INVALIDDATA; - } + // The offset for the YUV planes is the starting position of mdat. + extent_offsets[0] = avio_tell(pb); + // The offset for alpha plane is YUV offset + YUV size. + extent_offsets[1] = extent_offsets[0] + mov->avif_extent_length[0]; avio_write(pb, buf, buf_size); - // write extent offset. + // write extent offsets. pos_backup = avio_tell(pb); - avio_seek(pb, mov->avif_extent_pos, SEEK_SET); - avio_wb32(pb, mdat_pos); /* rewrite offset */ + for (i = 0; i < s->nb_streams; i++) { + if (extent_offsets[i] != (uint32_t)extent_offsets[i]) { + av_log(s, AV_LOG_ERROR, "extent offset does not fit in 32 bits\n"); + return AVERROR_INVALIDDATA; + } + avio_seek(pb, mov->avif_extent_pos[i], SEEK_SET); + avio_wb32(pb, extent_offsets[i]); /* rewrite offset */ + } avio_seek(pb, pos_backup, SEEK_SET); return 0; diff --git a/libavformat/movenc.h b/libavformat/movenc.h index 281576cc66..e4550f7900 100644 --- a/libavformat/movenc.h +++ b/libavformat/movenc.h @@ -246,8 +246,8 @@ typedef struct MOVMuxContext { int empty_hdlr_name; int movie_timescale; - int64_t avif_extent_pos; - int avif_extent_length; + int64_t avif_extent_pos[2]; // index 0 is YUV and 1 is Alpha. + int avif_extent_length[2]; // index 0 is YUV and 1 is Alpha. int is_animated_avif; } MOVMuxContext;