debian/ffmpeg-v4l2-request-fourier: new package

Mirror of arch/ffmpeg-v4l2-request-fourier into the Debian tree.
Same source pin (Kwiboo v4l2-request-n8.1 @ b57fbbe), same 2
patches (libudev-bypass-fallback + nv15-to-p010-unpack), same
configure flag policy (drop X11/AMF/CUDA/Bluray/Vulkan/SDL2/etc.
per Fourier fleet focus).

Output: single .deb at /usr/bin/ffmpeg + /usr/bin/ffprobe +
/usr/lib/aarch64-linux-gnu/libav*.so.61.  Conflicts/Replaces
the stock Debian ffmpeg + per-lib packages; takes epoch 2
(matches Debian's existing ffmpeg epoch).

Provides 'ffmpeg -hwaccel v4l2request' + '-hwaccel drm' routes
that drive rkvdec / hantro / cedrus / rpi-hevc-dec /
daedalus_v4l2 stateless decoders through libavcodec's hwdevice
DRM path, bypassing libva.  Required by mpv-fourier and
firefox-fourier as their backing FFmpeg; also the kdirect
bit-exact reference for libva-v4l2-request-fourier validation.

NOT strictly required for the VAAPI-only path on
daedalus-v4l2 hosts (stock Debian ffmpeg + libva-v4l2-request-
fourier covers that).  Install only when going firefox-fourier
or kdirect.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

debian/ffmpeg-v4l2-request-fourier/0001-libudev-bypass-fallback.patch

@@ -0,0 +1,166 @@
+--- a/libavutil/hwcontext_v4l2request.c
++++ b/libavutil/hwcontext_v4l2request.c
+@@ -19,12 +19,13 @@
+ #include "config.h"
+ 
+ #include <fcntl.h>
+ #include <linux/dma-buf.h>
+ #include <linux/media.h>
+ #include <sys/ioctl.h>
++#include <sys/stat.h>
+ #include <sys/mman.h>
+ #include <unistd.h>
+ 
+ #include <drm_fourcc.h>
+ #include <libudev.h>
+ 
+@@ -690,12 +691,125 @@
+     }
+ 
+     udev_enumerate_unref(enumerate);
+     return ret;
+ }
+ 
++/*
++ * Brute-force fallback used when libudev's scan fails (e.g. inside firefox's
++ * RDD sandbox where Mozilla's broker rejects fd-relative openat used by
++ * systemd's chase() symlink resolver). Iterates /dev/video[0..63], picks the
++ * one whose major/minor matches the requested devnum.
++ */
++static char *v4l2request_devnum_to_video_path_brute(dev_t devnum)
++{
++    char path[32];
++    struct stat st;
++    for (int i = 0; i < 64; i++) {
++        snprintf(path, sizeof(path), "/dev/video%d", i);
++        if (stat(path, &st) < 0)
++            continue;
++        if (st.st_rdev == devnum)
++            return av_strdup(path);
++    }
++    return NULL;
++}
++
++/* Brute-force version of v4l2request_probe_video_devices: replaces the
++ * udev_device_new_from_devnum + udev_device_get_devnode flow with
++ * stat()-based major/minor matching against /dev/video[0..63]. */
++static int v4l2request_probe_video_devices_brute(AVHWFramesContext *hwfc,
++                                                 uint32_t pixelformat,
++                                                 uint32_t buffersize)
++{
++    AVV4L2RequestFramesContext *fctx = hwfc->hwctx;
++    AVV4L2RequestFramesContextInternal *fctxi = fctx->internal;
++    struct media_device_info device_info;
++    struct media_v2_topology topology = {0};
++    struct media_v2_interface *interfaces;
++    char *path;
++    dev_t devnum;
++    int ret;
++
++    if (ioctl(fctxi->media_fd, MEDIA_IOC_DEVICE_INFO, &device_info) < 0)
++        return AVERROR(errno);
++
++    if (ioctl(fctxi->media_fd, MEDIA_IOC_G_TOPOLOGY, &topology) < 0)
++        return AVERROR(errno);
++
++    if (!topology.num_interfaces)
++        return AVERROR(ENOENT);
++
++    interfaces = av_calloc(topology.num_interfaces,
++                           sizeof(struct media_v2_interface));
++    if (!interfaces)
++        return AVERROR(ENOMEM);
++
++    topology.ptr_interfaces = (__u64)(uintptr_t)interfaces;
++    if (ioctl(fctxi->media_fd, MEDIA_IOC_G_TOPOLOGY, &topology) < 0) {
++        ret = AVERROR(errno);
++        goto fail;
++    }
++
++    ret = AVERROR(ENOENT);
++    for (unsigned i = 0; i < topology.num_interfaces; i++) {
++        if (interfaces[i].intf_type != MEDIA_INTF_T_V4L_VIDEO)
++            continue;
++
++        devnum = makedev(interfaces[i].devnode.major,
++                         interfaces[i].devnode.minor);
++        path = v4l2request_devnum_to_video_path_brute(devnum);
++        if (!path)
++            continue;
++
++        ret = v4l2request_probe_video_device(hwfc, path, pixelformat, buffersize);
++        if (!ret) {
++            av_log(hwfc, AV_LOG_INFO,
++                   "Using V4L2 media driver %s (brute-force) for %s\n",
++                   device_info.driver, av_fourcc2str(pixelformat));
++            av_free(path);
++            break;
++        }
++        av_free(path);
++    }
++
++fail:
++    av_free(interfaces);
++    return ret;
++}
++
++/* Brute-force fallback for v4l2request_probe_media_devices(). Iterates
++ * /dev/media[0..15], opens each, probes via topology+stat. */
++static int v4l2request_probe_media_devices_brute(AVHWFramesContext *hwfc,
++                                                 uint32_t pixelformat,
++                                                 uint32_t buffersize)
++{
++    AVV4L2RequestFramesContext *fctx = hwfc->hwctx;
++    AVV4L2RequestFramesContextInternal *fctxi = fctx->internal;
++    char path[32];
++    int ret = AVERROR(ENOENT);
++
++    for (int i = 0; i < 16; i++) {
++        snprintf(path, sizeof(path), "/dev/media%d", i);
++
++        fctxi->media_fd = open(path, O_RDWR);
++        if (fctxi->media_fd < 0)
++            continue;
++
++        ret = v4l2request_probe_video_devices_brute(hwfc, pixelformat,
++                                                    buffersize);
++        if (!ret)
++            return 0;
++
++        close(fctxi->media_fd);
++        fctxi->media_fd = -1;
++    }
++
++    return ret;
++}
++
+ static int v4l2request_open_decoder(AVHWFramesContext *hwfc)
+ {
+     AVV4L2RequestFramesContext *fctx = hwfc->hwctx;
+     uint32_t buffersize;
+     struct udev *udev;
+     int ret;
+@@ -712,12 +826,23 @@
+ 
+     buffersize = FFMAX(hwfc->width * hwfc->height * 3 / 2, 256 * 1024);
+ 
+     // Probe all media devices (auto-detection)
+     ret = v4l2request_probe_media_devices(hwfc, udev, fctx->pixelformat, buffersize);
+ 
++    // Brute-force fallback when libudev fails. Firefox-fourier hits this
++    // because Mozilla's RDD sandbox blocks fd-relative openat used by
++    // systemd's chase() symlink resolver inside udev_enumerate_scan_devices.
++    if (ret < 0) {
++        av_log(hwfc, AV_LOG_INFO,
++               "libudev probe failed (%d), falling back to brute-force /dev/media*\n",
++               ret);
++        ret = v4l2request_probe_media_devices_brute(hwfc, fctx->pixelformat,
++                                                    buffersize);
++    }
++
+     udev_unref(udev);
+     return ret;
+ }
+ 
+ static AVBufferRef *v4l2request_v4l2_buffer_alloc(AVHWFramesContext *hwfc,
+                                                   struct v4l2_format *format)

debian/ffmpeg-v4l2-request-fourier/0002-nv15-to-p010-unpack.patch

@@ -0,0 +1,178 @@
+From 0cd6e669735e453ec8772f111065bbb2f70a5bc6 Mon Sep 17 00:00:00 2001
+From: Markus Fritsche <mfritsche@reauktion.de>
+Date: Mon, 18 May 2026 07:27:10 +0000
+Subject: [PATCH] avutil/hwcontext_v4l2request: unpack NV15 to P010 in
+ transfer_data_from
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+V4L2_PIX_FMT_NV15 (RK3399/RK3588 rkvdec 10-bit 4:2:0 capture) is mapped to
+sw_format = AV_PIX_FMT_YUV420P10 in v4l2request_capture_pixelformats[]. The
+existing transfer_get_formats explicitly blanked the format list for that
+sw_format, so 'ffmpeg -hwaccel v4l2request -vf hwdownload,format=p010le' on
+a Hi10P / Main10 input failed at filter init with EINVAL before reaching
+the actual decode (which itself succeeds — 2 frames decoded cleanly).
+
+Expose AV_PIX_FMT_P010 as the transfer target for NV15-backed surfaces and
+unpack the packed 10-bit samples into the standard high-bits-of-16 layout
+inside transfer_data_from. Luma and chroma share the same packing format
+(5 bytes per 4 samples, little endian); chroma plane is W × H/2 samples
+for 4:2:0.
+
+The other 'needs custom unpack' sw_formats (YUV420P / Allwinner NV12_32L32
+tiled and YUV422P10 / rkvdec NV20) keep the original ENOSYS path because
+they need different unpack code that isn't covered by this patch.
+
+Closes marfrit/marfrit-packages#21.
+---
+ libavutil/hwcontext_v4l2request.c | 111 +++++++++++++++++++++++++++++-
+ 1 file changed, 110 insertions(+), 1 deletion(-)
+
+diff --git a/libavutil/hwcontext_v4l2request.c b/libavutil/hwcontext_v4l2request.c
+index b6633d9081..3842160dfb 100644
+--- a/libavutil/hwcontext_v4l2request.c
++++ b/libavutil/hwcontext_v4l2request.c
+@@ -1073,6 +1073,56 @@ fail:
+     return ret;
+ }
+ 
++/*
++ * Unpack one NV15-packed 10-bit plane (5 bytes per 4 samples, little endian)
++ * into a P010-style plane (10 bits in the high bits of a 16-bit container).
++ * `dst_stride` is in bytes; `src_stride` is bytes per row of NV15 data.
++ */
++static void v4l2request_nv15_unpack_plane_to_p010(const uint8_t *src,
++                                                  uint16_t *dst,
++                                                  unsigned width,
++                                                  unsigned height,
++                                                  unsigned src_stride,
++                                                  unsigned dst_stride)
++{
++    for (unsigned y = 0; y < height; y++) {
++        const uint8_t *s = src + y * src_stride;
++        uint16_t *d = (uint16_t *)((uint8_t *)dst + y * dst_stride);
++        unsigned x;
++
++        for (x = 0; x + 4 <= width; x += 4) {
++            uint16_t a = (uint16_t)s[0] | ((uint16_t)(s[1] & 0x03) << 8);
++            uint16_t b = ((uint16_t)s[1] >> 2) | ((uint16_t)(s[2] & 0x0F) << 6);
++            uint16_t c = ((uint16_t)s[2] >> 4) | ((uint16_t)(s[3] & 0x3F) << 4);
++            uint16_t e = ((uint16_t)s[3] >> 6) | ((uint16_t)s[4] << 2);
++
++            d[0] = (uint16_t)(a << 6);
++            d[1] = (uint16_t)(b << 6);
++            d[2] = (uint16_t)(c << 6);
++            d[3] = (uint16_t)(e << 6);
++
++            d += 4;
++            s += 5;
++        }
++
++        if (x < width) {
++            unsigned rem = width - x;
++            uint16_t pix[4] = { 0, 0, 0, 0 };
++
++            pix[0] = (uint16_t)s[0] | ((uint16_t)(s[1] & 0x03) << 8);
++            if (rem >= 2)
++                pix[1] = ((uint16_t)s[1] >> 2) | ((uint16_t)(s[2] & 0x0F) << 6);
++            if (rem >= 3)
++                pix[2] = ((uint16_t)s[2] >> 4) | ((uint16_t)(s[3] & 0x3F) << 4);
++            if (rem >= 4)
++                pix[3] = ((uint16_t)s[3] >> 6) | ((uint16_t)s[4] << 2);
++
++            for (unsigned j = 0; j < rem; j++)
++                d[j] = (uint16_t)(pix[j] << 6);
++        }
++    }
++}
++
+ static int v4l2request_transfer_get_formats(AVHWFramesContext *hwfc,
+                                             enum AVHWFrameTransferDirection dir,
+                                             enum AVPixelFormat **formats)
+@@ -1082,6 +1132,22 @@ static int v4l2request_transfer_get_formats(AVHWFramesContext *hwfc,
+     if (dir == AV_HWFRAME_TRANSFER_DIRECTION_TO)
+         return AVERROR(ENOSYS);
+ 
++    /*
++     * NV15-backed surfaces (sw_format = YUV420P10) are exposed as P010 to
++     * downstream filters: the unpack below converts the packed 10-bit
++     * samples into the standard high-bits-of-16 layout. Hi10P / Main10
++     * VAAPI/v4l2-request decode reaches userspace through this path.
++     */
++    if (hwfc->sw_format == AV_PIX_FMT_YUV420P10) {
++        fmts = av_malloc_array(2, sizeof(*fmts));
++        if (!fmts)
++            return AVERROR(ENOMEM);
++        fmts[0] = AV_PIX_FMT_P010;
++        fmts[1] = AV_PIX_FMT_NONE;
++        *formats = fmts;
++        return 0;
++    }
++
+     fmts = av_malloc_array(2, sizeof(*fmts));
+     if (!fmts)
+         return AVERROR(ENOMEM);
+@@ -1089,8 +1155,13 @@ static int v4l2request_transfer_get_formats(AVHWFramesContext *hwfc,
+     fmts[0] = hwfc->sw_format;
+     fmts[1] = AV_PIX_FMT_NONE;
+ 
++    /*
++     * Tiled-NV12-32L32 (Allwinner) and NV20 (rkvdec 4:2:2 10-bit) still need
++     * dedicated unpacks before hwdownload can consume them; leave them as
++     * "no transfer formats" so the filter graph reports the limitation
++     * rather than silently producing garbage.
++     */
+     if (hwfc->sw_format == AV_PIX_FMT_YUV420P ||
+-        hwfc->sw_format == AV_PIX_FMT_YUV420P10 ||
+         hwfc->sw_format == AV_PIX_FMT_YUV422P10)
+         fmts[0] = AV_PIX_FMT_NONE;
+ 
+@@ -1110,6 +1181,44 @@ static int v4l2request_transfer_data_from(AVHWFramesContext *hwfc,
+     map = av_frame_alloc();
+     if (!map)
+         return AVERROR(ENOMEM);
++
++    /*
++     * For NV15→P010, map the raw NV15 bytes (sw_format) and unpack into
++     * dst's P010 storage. Otherwise fall through to the original byte-copy
++     * path used for 1:1 sw_format matches (NV12, NV16, AFBC handled by DRM).
++     */
++    if (hwfc->sw_format == AV_PIX_FMT_YUV420P10) {
++        /*
++         * Only P010 is advertised by transfer_get_formats for this sw_format;
++         * a caller that bypasses get_formats and asks for anything else would
++         * silently corrupt output via av_frame_copy on NV15-packed bytes.
++         * Reject explicitly.
++         */
++        if (dst->format != AV_PIX_FMT_P010) {
++            ret = AVERROR(ENOSYS);
++            goto fail;
++        }
++
++        map->format = hwfc->sw_format;
++        ret = v4l2request_map_frame(hwfc, map, src);
++        if (ret)
++            goto fail;
++
++        v4l2request_nv15_unpack_plane_to_p010(map->data[0],
++                                              (uint16_t *)dst->data[0],
++                                              dst->width, dst->height,
++                                              map->linesize[0],
++                                              dst->linesize[0]);
++        /* NV15 chroma plane is W × H/2 samples (4:2:0, UV interleaved). */
++        v4l2request_nv15_unpack_plane_to_p010(map->data[1],
++                                              (uint16_t *)dst->data[1],
++                                              dst->width, dst->height / 2,
++                                              map->linesize[1],
++                                              dst->linesize[1]);
++        ret = 0;
++        goto fail;
++    }
++
+     map->format = dst->format;
+ 
+     ret = v4l2request_map_frame(hwfc, map, src);
+-- 
+2.47.3
+

debian/ffmpeg-v4l2-request-fourier/build-deb.sh

@@ -0,0 +1,177 @@
+#!/bin/bash
+# Build ffmpeg-v4l2-request-fourier_<ver>_arm64.deb (the Kwiboo FFmpeg
+# fork with the V4L2-Request API hwaccel patches).
+#
+# Mirror of arch/ffmpeg-v4l2-request-fourier into the Debian tree.
+# Provides the patched `ffmpeg` + `ffprobe` binaries plus the shared
+# libav* libraries with v4l2-request support, so consumers like
+# mpv-fourier (and the kdirect bit-exact reference test rig) work
+# end-to-end without a stock-Debian FFmpeg fallback.
+#
+# Conflicts: ffmpeg, libav* — this is a drop-in replacement.  Pi 5 /
+# CM5 (BCM2712) hosts using daedalus_v4l2 + libva-v4l2-request-fourier
+# DON'T strictly need this package (stock Debian ffmpeg + libva path
+# is sufficient for the VAAPI route), but the kdirect bit-exact
+# reference + firefox-fourier / mpv-fourier consumers do.
+#
+# Big build: 25-40 min on a runner.  Output is a single .deb that
+# bundles ffmpeg/ffprobe + libavcodec.so.61 + libavformat.so.61 etc.
+# all together — no split per-library subpackages.  Easier to consume,
+# trades off finer-grained downgrades.
+#
+# Sibling Arch package: ../../arch/ffmpeg-v4l2-request-fourier/PKGBUILD
+# Upstream: https://github.com/Kwiboo/FFmpeg (branch v4l2-request-n8.1)
+set -euo pipefail
+
+# Same pin as arch/ — v4l2-request-n8.1 tip 2026-04-24.
+UPSTREAM_COMMIT=b57fbbe50c9b2656fad86a1a7eeabfd2b2a50935
+FFMPEG_VERSION=8.1
+# epoch 2 matches Debian's stock ffmpeg (currently 7:7.1.x in trixie);
+# +rfourier suffix to avoid colliding with upstream/Debian rebuilds.
+PKGVER=2:${FFMPEG_VERSION}+rfourier+gb57fbbe
+PKGREL=1
+
+HERE=$(dirname "$(readlink -f "$0")")
+
+# Reproducible build.  2026-05-18 23:00 UTC — Phase 8.13 close.
+export SOURCE_DATE_EPOCH=1779231600
+
+work=$(mktemp -d)
+trap "rm -rf $work" EXIT
+
+cd "$work"
+git clone --depth 1 \
+    --branch v4l2-request-n8.1 \
+    https://github.com/Kwiboo/FFmpeg.git FFmpeg
+cd FFmpeg
+# git fetch the specific commit (depth=1 of branch tip might not be it)
+if [ "$(git rev-parse HEAD)" != "$UPSTREAM_COMMIT" ]; then
+    git fetch origin "$UPSTREAM_COMMIT"
+    git checkout "$UPSTREAM_COMMIT"
+fi
+
+# Apply patches (same as Arch).
+patch -Np1 -i "$HERE/0001-libudev-bypass-fallback.patch"
+patch -Np1 -i "$HERE/0002-nv15-to-p010-unpack.patch"
+
+# Configure with Arch-parity flags.  Drops the same set of features
+# (X11, AMF, CUDA, FireWire, AviSynth, Bluray, OpenMPT, JPEG-XL,
+# Theora, XVid, rsvg, soxr, ssh, vidstab, modplug, SDL2, Vulkan,
+# JACK, GSM, Speex) — not needed on the Fourier fleet, keeps the .deb
+# smaller and the dependency graph tighter.
+./configure \
+    --prefix=/usr \
+    --libdir=/usr/lib/aarch64-linux-gnu \
+    --shlibdir=/usr/lib/aarch64-linux-gnu \
+    --incdir=/usr/include/aarch64-linux-gnu \
+    --disable-debug \
+    --disable-static \
+    --disable-doc \
+    --disable-stripping \
+    --enable-shared \
+    --enable-gpl \
+    --enable-version3 \
+    --enable-pic \
+    --enable-neon \
+    --arch=aarch64 \
+    --enable-libdrm \
+    --enable-libv4l2 \
+    --enable-libudev \
+    --enable-v4l2-request \
+    --enable-v4l2_m2m \
+    --enable-vaapi \
+    --enable-opengl \
+    --enable-gnutls \
+    --enable-fontconfig \
+    --enable-libass \
+    --enable-libfreetype \
+    --enable-libfribidi \
+    --enable-libxml2 \
+    --enable-libpulse \
+    --enable-libdav1d \
+    --enable-libopus \
+    --enable-libvorbis \
+    --enable-libmp3lame \
+    --enable-libvpx \
+    --enable-libx264 \
+    --enable-libx265 \
+    --enable-libwebp \
+    --host-cflags='-fPIC'
+
+make -j"$(nproc)"
+make tools/qt-faststart
+
+# Stage
+ROOT="$work/pkgroot"
+make DESTDIR="$ROOT" install
+install -Dm755 tools/qt-faststart "$ROOT/usr/bin/qt-faststart"
+
+# Doc
+mkdir -p "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier" "$ROOT/DEBIAN"
+install -Dm644 "$HERE/debian/copyright" \
+    "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/copyright"
+install -Dm644 "$HERE/debian/changelog" \
+    "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/changelog.Debian"
+gzip -9 -n "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/changelog.Debian"
+
+cat > "$ROOT/DEBIAN/control" <<EOF
+Package: ffmpeg-v4l2-request-fourier
+Version: ${PKGVER}-${PKGREL}
+Section: video
+Priority: optional
+Architecture: arm64
+Depends: libc6,
+         libdrm2,
+         libfontconfig1,
+         libfreetype6,
+         libfribidi0,
+         libxml2,
+         libpulse0,
+         libdav1d7 | libdav1d6,
+         libopus0,
+         libvorbis0a,
+         libvorbisenc2,
+         libmp3lame0,
+         libvpx9 | libvpx8 | libvpx7,
+         libx264-164 | libx264-163,
+         libx265-215 | libx265-209 | libx265-199,
+         libwebp7 | libwebp6,
+         libwebpmux3,
+         libass9,
+         libgnutls30,
+         libudev1,
+         libv4l-0,
+         libva2,
+         libva-drm2
+Conflicts: ffmpeg, libavcodec61, libavformat61, libavutil59,
+           libswresample5, libswscale8, libavdevice61, libavfilter10,
+           libpostproc58
+Replaces: ffmpeg, libavcodec61, libavformat61, libavutil59,
+          libswresample5, libswscale8, libavdevice61, libavfilter10,
+          libpostproc58
+Provides: ffmpeg (= ${PKGVER}-${PKGREL}),
+          libavcodec.so.61,
+          libavformat.so.61,
+          libavutil.so.59
+Maintainer: Markus Fritsche <mfritsche@reauktion.de>
+Homepage: https://github.com/Kwiboo/FFmpeg
+Description: FFmpeg with V4L2 Request API hwaccel (Kwiboo fork)
+ FFmpeg ${FFMPEG_VERSION} patched with the V4L2 Request API stateless
+ video decoder hwaccel — Kwiboo's long-running rebase of Jernej
+ Škrabec's v4l2-request patchset onto FFmpeg release tags.
+ .
+ Provides 'ffmpeg -hwaccel v4l2request' / '-hwaccel drm' routes that
+ drive rkvdec / hantro / cedrus / rpi-hevc-dec / daedalus_v4l2
+ stateless decoders directly through libavcodec's hwdevice DRM path,
+ bypassing libva.  Used by mpv-fourier and firefox-fourier as their
+ backing FFmpeg, and as the kdirect bit-exact reference in libva-v4l2-
+ request-fourier validation.
+ .
+ Drops X11/AMF/CUDA/Bluray/JACK/Vulkan/SDL2/Theora/XVid/Speex/JPEG-XL
+ per Fourier fleet policy (Wayland + ARM + video-decode focus).
+ No 'ffplay' binary; mpv-fourier covers interactive playback.
+EOF
+
+DEB_OUT="ffmpeg-v4l2-request-fourier_${PKGVER//:/%3a}-${PKGREL}_arm64.deb"
+dpkg-deb --root-owner-group --build "$ROOT" "$HERE/$DEB_OUT"
+echo "built: $HERE/$DEB_OUT"

debian/ffmpeg-v4l2-request-fourier/debian/changelog

@@ -0,0 +1,14 @@
+ffmpeg-v4l2-request-fourier (2:8.1+rfourier+gb57fbbe-1) bookworm trixie; urgency=medium
+
+  * Initial Debian packaging for the Kwiboo FFmpeg fork with V4L2
+    Request API hwaccel patches.
+  * Mirror of arch/ffmpeg-v4l2-request-fourier (same pin b57fbbe,
+    same configure flags, same 2 patches: libudev-bypass-fallback +
+    nv15-to-p010-unpack).
+  * Drop-in replacement for Debian's stock ffmpeg + libav*; takes
+    epoch 2 to win the apt version comparison.
+  * Required by mpv-fourier and firefox-fourier; not strictly
+    required for the VAAPI-only path on daedalus-v4l2 hosts (stock
+    libva + Debian ffmpeg works there).
+
+ -- Markus Fritsche <mfritsche@reauktion.de>  Mon, 18 May 2026 23:00:00 +0000

debian/ffmpeg-v4l2-request-fourier/debian/control

@@ -0,0 +1,61 @@
+Source: ffmpeg-v4l2-request-fourier
+Section: video
+Priority: optional
+Maintainer: Markus Fritsche <mfritsche@reauktion.de>
+Build-Depends: debhelper-compat (= 13),
+               git,
+               nasm,
+               pkg-config,
+               libass-dev,
+               libdrm-dev,
+               libfontconfig1-dev,
+               libfreetype6-dev,
+               libfribidi-dev,
+               libgnutls28-dev,
+               libmp3lame-dev,
+               libopus-dev,
+               libpulse-dev,
+               libudev-dev,
+               libv4l-dev,
+               libva-dev,
+               libvorbis-dev,
+               libvpx-dev,
+               libwebp-dev,
+               libx264-dev,
+               libx265-dev,
+               libxml2-dev,
+               libdav1d-dev,
+               linux-libc-dev
+Standards-Version: 4.6.2
+Homepage: https://github.com/Kwiboo/FFmpeg
+
+Package: ffmpeg-v4l2-request-fourier
+Architecture: arm64
+Depends: ${misc:Depends}, ${shlibs:Depends}
+Conflicts: ffmpeg,
+           libavcodec61, libavformat61, libavutil59,
+           libswresample5, libswscale8, libavdevice61, libavfilter10,
+           libpostproc58
+Replaces: ffmpeg,
+          libavcodec61, libavformat61, libavutil59,
+          libswresample5, libswscale8, libavdevice61, libavfilter10,
+          libpostproc58
+Provides: ffmpeg (= ${binary:Version}),
+          libavcodec.so.61,
+          libavformat.so.61,
+          libavutil.so.59
+Description: FFmpeg with V4L2 Request API hwaccel (Kwiboo fork)
+ FFmpeg 8.1 patched with the V4L2 Request API stateless video decoder
+ hwaccel — Kwiboo's long-running rebase of Jernej Škrabec's
+ v4l2-request patchset onto FFmpeg release tags.
+ .
+ Provides 'ffmpeg -hwaccel v4l2request' / '-hwaccel drm' routes that
+ drive rkvdec / hantro / cedrus / rpi-hevc-dec / daedalus_v4l2
+ stateless decoders directly through libavcodec's hwdevice DRM path,
+ bypassing libva. Used by mpv-fourier and firefox-fourier as their
+ backing FFmpeg, and as the kdirect bit-exact reference in
+ libva-v4l2-request-fourier validation.
+ .
+ Drops X11/AMF/CUDA/Bluray/JACK/Vulkan/SDL2/Theora/XVid/Speex/JPEG-XL
+ per Fourier fleet policy (Wayland + ARM + video-decode focus). No
+ 'ffplay' binary; mpv-fourier covers interactive playback.

debian/ffmpeg-v4l2-request-fourier/debian/copyright

@@ -0,0 +1,21 @@
+Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
+Upstream-Name: FFmpeg (Kwiboo v4l2-request fork)
+Upstream-Contact: Niklas Haas <niklas@haasn.dev>, Jernej Škrabec, Kwiboo
+Source: https://github.com/Kwiboo/FFmpeg
+
+Files: *
+Copyright: 2000-2026 The FFmpeg developers
+License: GPL-3.0-or-later
+
+Files: 0001-libudev-bypass-fallback.patch 0002-nv15-to-p010-unpack.patch
+Copyright: 2024-2026 Markus Fritsche <fritsche.markus@gmail.com>
+License: GPL-3.0-or-later
+
+License: GPL-3.0-or-later
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+ .
+ On Debian systems, the complete text of the GNU General Public
+ License v3 can be found in `/usr/share/common-licenses/GPL-3'.