[FFmpeg-devel,v12] avformat: add farbfeld muxer and demuxer

diff --git a/Changelog b/Changelog
index 06c00e981a..3024e8d7fb 100644
--- a/Changelog
+++ b/Changelog
@@ -14,6 +14,7 @@  version <next>:
 - xHE-AAC decoder
 - removed DEC Alpha DSP and support code
 - VVC encoding support via libvvenc
+- farbfeld muxer and demuxer
 
 
 version 7.0:
diff --git a/doc/general_contents.texi b/doc/general_contents.texi
index e7cf4f8239..9929c23654 100644
--- a/doc/general_contents.texi
+++ b/doc/general_contents.texi
@@ -786,6 +786,7 @@  following image formats are supported:
     @tab Digital Picture Exchange
 @item EXR          @tab   @tab X
     @tab OpenEXR
+@item FF           @tab X @tab X
 @item FITS         @tab X @tab X
     @tab Flexible Image Transport System
 @item HDR          @tab X @tab X
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 7ca68a7036..ab8f8216ff 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -204,6 +204,8 @@  OBJS-$(CONFIG_EA_DEMUXER)                += electronicarts.o
 OBJS-$(CONFIG_EAC3_DEMUXER)              += ac3dec.o rawdec.o
 OBJS-$(CONFIG_EAC3_MUXER)                += rawenc.o
 OBJS-$(CONFIG_EPAF_DEMUXER)              += epafdec.o pcm.o
+OBJS-$(CONFIG_FARBFELD_DEMUXER)          += farbfelddec.o
+OBJS-$(CONFIG_FARBFELD_MUXER)            += farbfeldenc.o
 OBJS-$(CONFIG_FFMETADATA_DEMUXER)        += ffmetadec.o
 OBJS-$(CONFIG_FFMETADATA_MUXER)          += ffmetaenc.o
 OBJS-$(CONFIG_FIFO_MUXER)                += fifo.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 305fa46532..0cda72c195 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -161,6 +161,8 @@  extern const FFOutputFormat ff_eac3_muxer;
 extern const FFInputFormat  ff_epaf_demuxer;
 extern const FFInputFormat  ff_evc_demuxer;
 extern const FFOutputFormat ff_evc_muxer;
+extern const FFInputFormat  ff_farbfeld_demuxer;
+extern const FFOutputFormat ff_farbfeld_muxer;
 extern const FFOutputFormat ff_f4v_muxer;
 extern const FFInputFormat  ff_ffmetadata_demuxer;
 extern const FFOutputFormat ff_ffmetadata_muxer;
diff --git a/libavformat/farbfelddec.c b/libavformat/farbfelddec.c
new file mode 100644
index 0000000000..a87cdb4674
--- /dev/null
+++ b/libavformat/farbfelddec.c
@@ -0,0 +1,66 @@ 
+/*
+ * Copyright (c) 2024 Marcus B Spencer
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "demux.h"
+#include "internal.h"
+
+static int farbfeld_read_header(AVFormatContext *ctx)
+{
+    AVStream *st = avformat_new_stream(ctx, NULL);
+    char magic[8];
+    int ret;
+
+    if (avio_size(ctx->pb) < 16)
+        return AVERROR_INVALIDDATA;
+
+    if ((ret = avio_read(ctx->pb, magic, 8)) < 0)
+        return ret;
+
+    if (memcmp(magic, "farbfeld", 8))
+        return AVERROR_INVALIDDATA;
+
+    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    st->codecpar->format     = AV_PIX_FMT_RGBA64BE;
+    st->codecpar->codec_id   = AV_CODEC_ID_RAWVIDEO;
+
+    st->codecpar->width         = avio_rb32(ctx->pb);
+    st->codecpar->height        = avio_rb32(ctx->pb);
+    st->codecpar->framerate.num = 25;
+    st->codecpar->framerate.den = 1;
+    st->avg_frame_rate          =
+    st->r_frame_rate            = st->codecpar->framerate;
+
+    return 0;
+}
+
+static int farbfeld_read_packet(AVFormatContext *ctx, AVPacket *pkt)
+{
+    return av_get_packet(ctx->pb, pkt, avio_size(ctx->pb) - 16);
+}
+
+const FFInputFormat ff_farbfeld_demuxer = {
+    .p.name       = "farbfeld",
+    .p.long_name  = NULL_IF_CONFIG_SMALL("farbfeld uncompressed image"),
+    .p.flags      = AVFMT_NOTIMESTAMPS | AVFMT_EXPERIMENTAL,
+    .p.extensions = "ff",
+    .read_header  = farbfeld_read_header,
+    .read_packet  = farbfeld_read_packet,
+};
diff --git a/libavformat/farbfeldenc.c b/libavformat/farbfeldenc.c
new file mode 100644
index 0000000000..a1507d02c8
--- /dev/null
+++ b/libavformat/farbfeldenc.c
@@ -0,0 +1,164 @@ 
+/*
+ * YUV4MPEG muxer
+ * Image format
+ *
+ * Modified by Marcus B Spencer to suit the farbfeld muxer on 30 June 2024
+ *
+ * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
+ * Copyright (c) 2004 Michael Niedermayer
+ * Copyright (c) 2024 Marcus B Spencer
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "internal.h"
+#include "libavutil/avstring.h"
+#include "libavutil/frame.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
+#include "libavutil/mem.h"
+#include "mux.h"
+
+#define PLANE_COUNT 4 // required by av_image_copy_to_buffer
+
+typedef struct FarbfeldMuxContext {
+    const AVClass *class;
+    int start_number, img_number;
+} FarbfeldMuxContext;
+
+static int farbfeld_init(AVFormatContext *ctx)
+{
+    FarbfeldMuxContext *priv = ctx->priv_data;
+
+    if (ctx->streams[0]->codecpar->codec_id != AV_CODEC_ID_WRAPPED_AVFRAME &&
+        ctx->streams[0]->codecpar->codec_id != AV_CODEC_ID_RAWVIDEO) {
+        av_log(ctx, AV_LOG_ERROR, "Codec not supported.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (ctx->streams[0]->codecpar->format != AV_PIX_FMT_RGBA64BE) {
+        av_log(ctx, AV_LOG_ERROR,
+            "farbfeld only supports the rgba64be pixel format. "
+            "Add \"-pix_fmt rgba64be\" to your output options to resolve "
+            "this error.\n"
+        );
+        return AVERROR_INVALIDDATA;
+    }
+
+    priv->img_number = priv->start_number;
+
+    return 0;
+}
+
+static int farbfeld_write_packet(AVFormatContext *ctx, AVPacket *pkt)
+{
+    AVStream *st = ctx->streams[pkt->stream_index];
+    int width = st->codecpar->width, height = st->codecpar->height;
+    FarbfeldMuxContext *priv = ctx->priv_data;
+    const uint8_t *planes[PLANE_COUNT];
+    enum AVPixelFormat pix_fmt;
+    char filename[1024];
+    const AVFrame *p;
+    int raw_img_size;
+    AVIOContext *pb;
+    uint8_t *dst;
+    int ret;
+
+    if ((ret = av_get_frame_filename2(filename, sizeof filename, ctx->url,
+        priv->img_number, AV_FRAME_FILENAME_FLAGS_MULTIPLE)) < 0) {
+        if (priv->img_number == priv->start_number) {
+            av_log(ctx, AV_LOG_WARNING, "The specified filename '%s' does not contain an image sequence pattern or a pattern is invalid.\n", ctx->url);
+            av_log(ctx, AV_LOG_WARNING, "Use a pattern such as %%03d for an image sequence.\n");
+            av_strlcpy(filename, ctx->url, sizeof filename);
+        } else {
+            av_log(ctx, AV_LOG_ERROR, "Cannot write more than one file with the same name.\n");
+            return AVERROR(EINVAL);
+        }
+    }
+
+    if ((ret = ctx->io_open(ctx, &pb, filename, AVIO_FLAG_WRITE, NULL)) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Could not open file : %s\n", filename);
+        return ret;
+    }
+
+    avio_write(pb, "farbfeld", 8);
+
+    avio_wb32(pb, width);
+    avio_wb32(pb, height);
+
+    if (st->codecpar->codec_id == AV_CODEC_ID_RAWVIDEO) {
+        avio_write(pb, pkt->data, pkt->size);
+        return 0;
+    }
+
+    p       = (const AVFrame *)pkt->data;
+    pix_fmt = st->codecpar->format;
+
+    if ((raw_img_size = av_image_get_buffer_size(pix_fmt, width, height, 1)) < 0)
+        return raw_img_size;
+
+    if (!(dst = av_malloc(raw_img_size)))
+        return AVERROR(ENOMEM);
+
+    for (int i = 0; i < PLANE_COUNT; i++)
+        planes[i] = p->data[i];
+
+    if ((ret = av_image_copy_to_buffer(dst, raw_img_size, planes, p->linesize,
+        pix_fmt, width, height, 1)) < 0)
+        return ret;
+
+    avio_write(pb, dst, raw_img_size);
+
+    av_freep(&dst);
+
+    priv->img_number++;
+
+    avio_flush(pb);
+
+    return ff_format_io_close(ctx, &pb);
+}
+
+#define OFFSET(x) offsetof(FarbfeldMuxContext, x)
+#define ENC AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption muxoptions[] = {
+    { "start_number", "set first number in the sequence", OFFSET(start_number), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, INT_MAX, ENC },
+    { NULL },
+};
+
+static const AVClass farbfeld_mux_class = {
+    .class_name = "farbfeld muxer",
+    .item_name  = av_default_item_name,
+    .option     = muxoptions,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+const FFOutputFormat ff_farbfeld_muxer = {
+    .p.name           = "farbfeld",
+    .p.long_name      = NULL_IF_CONFIG_SMALL("farbfeld uncompressed image"),
+    .p.extensions     = "ff",
+    .p.audio_codec    = AV_CODEC_ID_NONE,
+    .p.video_codec    = AV_CODEC_ID_WRAPPED_AVFRAME,
+    .p.subtitle_codec = AV_CODEC_ID_NONE,
+    .p.flags          = AVFMT_NOTIMESTAMPS | AVFMT_NOFILE,
+    .p.priv_class     = &farbfeld_mux_class,
+    .priv_data_size   = sizeof(FarbfeldMuxContext),
+    .init             = farbfeld_init,
+    .write_packet     = farbfeld_write_packet,
+    .flags_internal   = FF_OFMT_FLAG_MAX_ONE_OF_EACH,
+};
diff --git a/libavformat/version.h b/libavformat/version.h
index af7d0a1024..e2634b85ae 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -31,7 +31,7 @@ 
 
 #include "version_major.h"
 
-#define LIBAVFORMAT_VERSION_MINOR   4
+#define LIBAVFORMAT_VERSION_MINOR   5
 #define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \