6 Commits

Author SHA1 Message Date
marfrit d449ec1073 daedalus-v4l2 + daedalus-v4l2-dkms: bump to 872eec5 — PROTO_MAX_PAYLOAD 1 MiB (#20)
Picks up reauktion/daedalus-v4l2 PR #20 (closes #19): wire-protocol
cap DAEDALUS_PROTO_MAX_PAYLOAD raised from 64 KiB to 1 MiB.
DAEDALUS_MAX_BITSTREAM follows; daedalus_fill_output_fmt now reports
OUTPUT_MPLANE sizeimage = ~1 MiB.

Fixes the Firefox YouTube avc1 SW-fallback observed on higgs when
any H.264 slice exceeded 64 KiB (routine on 720p+ streams).
libva-v4l2-request-fourier's S_FMT-driven OUTPUT-pool resize was
clamping back to 65484 and Firefox lost the slice; now the kernel
honours the larger sizeimage.

Both packages bumped to 0.1.0+r45+g872eec5-1:

  - daedalus-v4l2 (daemon): r43 -> r45.  Daemon-side allocations
    are dynamic, so the only growth is one ~1 MiB read buffer per
    daemon process at startup.
  - daedalus-v4l2-dkms (kernel module): r33 -> r45.  Skips the
    daemon-only bumps r37/r39/r41/r43 (no kernel/include change in
    that range) and lands the PROTO_MAX_PAYLOAD bump.

LOCK-STEP INSTALL REQUIRED: effective cap is min(kernel, daemon).
A stale kernel with a new daemon (or vice versa) still rejects
>64 KiB payloads.  apt/pacman should pick both up in one
transaction since they share the same upstream pin.

Wire-protocol value-only change in include/daedalus_v4l2_proto.h;
struct layout unchanged.  DAEDALUS_PROTO_VERSION stays at 0.
2026-05-22 20:50:04 +02:00
marfrit 9d30c34be9 Merge pull request 'daedalus-v4l2: 6e6dfa1 -> 1d8f5af — pause-time tiny-bitstream filter (#18)' (#88) from claude-noether/marfrit-packages:noether/daedalus-bump-1d8f5af-pause-filter into main
Reviewed-on: marfrit/marfrit-packages#88
2026-05-22 16:20:14 +00:00
marfrit 1ca18ac130 daedalus-v4l2: 6e6dfa1 -> 1d8f5af — pause-time tiny-bitstream filter (#18)
Picks up reauktion/daedalus-v4l2 PR #18 (closes #17): daemon drops
degenerate (<4 byte) bitstreams at REQ_DECODE entry instead of
letting avcodec_send_packet emit AVERROR_INVALIDDATA, replies
RESP_FRAME NO_FRAME so libva's V4L2 surface pool stays alive.

Fixes the Firefox YouTube avc1 pause→resume regression observed on
higgs: libva-v4l2-request-fourier flushes a 3-byte stub into
OUTPUT_MPLANE at the pause boundary; the old daemon path turned
that into a decode failure, Firefox marked H.264-via-VAAPI as
broken for the session, and routed every subsequent frame to
libmozavcodec SW.  After this bump the daemon logs 'tiny bitstream
3 bytes — dropping as no-op' and the next real REQ_DECODE
proceeds normally.

Wire protocol unchanged.  daedalus-v4l2-dkms bump not needed.
2026-05-22 18:16:33 +02:00
marfrit cf9eef6cfa Merge pull request 'ffmpeg-v4l2-request-fourier: restore AV_CODEC_FLAG_LOW_DELAY in H.264 decoder' (#87) from claude-noether/marfrit-packages:noether/ffmpeg-fourier-restore-low-delay into main
Reviewed-on: marfrit/marfrit-packages#87
2026-05-22 14:27:43 +00:00
marfrit 5c69460722 ffmpeg-v4l2-request-fourier: restore AV_CODEC_FLAG_LOW_DELAY in H.264 decoder
FFmpeg 8.x dropped the H.264 decoder's low_delay code path —
AV_CODEC_FLAG_LOW_DELAY no longer prevents h264_select_output_frame
from running the display-order DPB output queue.  The daedalus-v4l2
daemon's `ctx->flags |= AV_CODEC_FLAG_LOW_DELAY` at
daemon/src/decoder.c:202 has been a silent no-op since the SONAME
61→62 jump landed in reauktion/daedalus-v4l2 PR #16; on Firefox
YouTube this re-introduced the 2-1-4-3 B-frame pair-swap that PR
#12's daemon flag was supposed to prevent.

Fix lives in libavcodec, not the daemon: restore the documented
LOW_DELAY semantics so the daemon (and any other V4L2-stateless-
style consumer) keeps the one-frame-per-send_packet decode-order
output contract it already declares.

## Patch

0006-h264-restore-low-delay.patch touches libavcodec/h264_slice.c:

- h264_select_output_frame: early-exit when LOW_DELAY is set.
  Emit the just-decoded picture as next_output_pic, mirror the
  corruption / recovery-point tracking the main path performs,
  skip delayed_pic[] / POC reorder machinery entirely.

- h264_field_start: suppress the SPS-driven
  `has_b_frames = sps->num_reorder_frames` clobber when LOW_DELAY
  is set.  Without this the per-slice bitstream_restriction_flag
  re-pickup would reintroduce a nonzero reorder buffer mid-stream
  even after the daemon set has_b_frames=0 at avcodec_open2.

## Why not daemon-side

A daemon SPS-rewrite (`num_reorder_frames=0`) was considered but
rejected: it works only for the daemon's reconstructed SPS NAL,
not for any in-band SPS the daemon dlopens libavformat to parse
in other code paths.  Restoring documented FFmpeg flag semantics
is the smaller, more durable change and keeps the daemon
interface stable.

## Packaging

- PKGREL/pkgrel bump to 9.
- No new build-deps, no Depends change.
- Substitution arc cycles 6/7/8 unchanged.

## Refs

- reauktion/daedalus-v4l2#11 / #12 (LOW_DELAY half-measure on
  daemon side, originally landed against FFmpeg 7.x).
- daemon/src/decoder.c:202 (`ctx->flags |= AV_CODEC_FLAG_LOW_DELAY`
  for H.264 only — unchanged, but now actually has effect again).
2026-05-22 14:20:37 +02:00
marfrit d11a52405d Merge pull request 'ffmpeg-v4l2-request-fourier: substitute H.264 luma-v deblock → daedalus-fourier' (#86) from claude-noether/marfrit-packages:noether/ffmpeg-fourier-deblock-luma-v-daedalus into main
Reviewed-on: marfrit/marfrit-packages#86
2026-05-22 10:29:09 +00:00
11 changed files with 278 additions and 22 deletions
+3 -3
View File
@@ -23,10 +23,10 @@ _module=daedalus_v4l2
# content-equivalent to f0d4186 plus PR #4 (cosmetic menu ctrls). # content-equivalent to f0d4186 plus PR #4 (cosmetic menu ctrls).
# PROTO_VERSION drops 1 → 0; lock-step install with # PROTO_VERSION drops 1 → 0; lock-step install with
# daedalus-v4l2 0.1.0.r33.5d8b436 REQUIRED. # daedalus-v4l2 0.1.0.r33.5d8b436 REQUIRED.
_commit=5d8b4369e58ab947d1c56b1f718293c57c6065b5 _commit=872eec505eb91b561892d02a0526749348ddc121
pkgver=0.1.0.r33.5d8b436 pkgver=0.1.0.r45.872eec5
pkgrel=1 # reset for new upstream pin (5d8b436 — revert parking design) pkgrel=1 # reset for new upstream pin (872eec5 — PROTO_MAX_PAYLOAD 64 KiB -> 1 MiB, closes #19); lock-step with daedalus-v4l2 0.1.0.r45.872eec5 REQUIRED
pkgdesc="V4L2 stateless decoder shim kernel module (DKMS) — Pi 5 / CM5" pkgdesc="V4L2 stateless decoder shim kernel module (DKMS) — Pi 5 / CM5"
arch=('any') arch=('any')
url="https://git.reauktion.de/reauktion/daedalus-v4l2" url="https://git.reauktion.de/reauktion/daedalus-v4l2"
+3 -3
View File
@@ -23,12 +23,12 @@ _upstreampkg=daedalus-v4l2
# (daedalus-v4l2#11). Daemon still needs daedalus-fourier at # (daedalus-v4l2#11). Daemon still needs daedalus-fourier at
# build time (Arch packaging for that is a follow-up; Debian side # build time (Arch packaging for that is a follow-up; Debian side
# fetches inline via build-deb.sh). # fetches inline via build-deb.sh).
_commit=6e6dfa144da7bc7fa8be50c8da91d7d1c6132a2c _commit=872eec505eb91b561892d02a0526749348ddc121
# 0.1.0 (pre-1.0) + commit count + short sha. Bump the .Y on each # 0.1.0 (pre-1.0) + commit count + short sha. Bump the .Y on each
# Phase 8.x close. pkgver() recomputes at build time. # Phase 8.x close. pkgver() recomputes at build time.
pkgver=0.1.0.r41.6e6dfa1 pkgver=0.1.0.r45.872eec5
pkgrel=1 # reset for new upstream pin (6e6dfa1 — soname 62 via /opt/fourier) pkgrel=1 # reset for new upstream pin (872eec5 — PROTO_MAX_PAYLOAD 64 KiB -> 1 MiB, closes #19); lock-step with daedalus-v4l2-dkms 0.1.0.r45.872eec5 REQUIRED
pkgdesc="Userspace daemon for the daedalus-v4l2 V4L2 stateless decoder shim (VP9/AV1/H.264 on Pi 5 / CM5)" pkgdesc="Userspace daemon for the daedalus-v4l2 V4L2 stateless decoder shim (VP9/AV1/H.264 on Pi 5 / CM5)"
arch=('aarch64') arch=('aarch64')
url="https://git.reauktion.de/reauktion/daedalus-v4l2" url="https://git.reauktion.de/reauktion/daedalus-v4l2"
@@ -0,0 +1,82 @@
From 0d1292ea99bc4e5fa2da438259fa01a2374e3e04 Mon Sep 17 00:00:00 2001
From: Markus Fritsche <mfritsche@reauktion.de>
Date: Fri, 22 May 2026 14:18:25 +0200
Subject: [PATCH] avcodec/h264: restore AV_CODEC_FLAG_LOW_DELAY semantics
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
FFmpeg 8.x dropped the H.264 decoder's low_delay path —
AV_CODEC_FLAG_LOW_DELAY no longer prevents
h264_select_output_frame from running the display-order DPB
output queue. V4L2-stateless-style consumers (daedalus-v4l2
daemon, libva-v4l2-request-fourier) that set the flag end up
seeing the 2-1-4-3 pair-swap pattern on B-frame streams again.
Restore the documented semantics:
- Early-exit at the top of h264_select_output_frame when the
flag is set: emit the just-decoded picture immediately as
next_output_pic, mirror the corruption / recovery-point
tracking the main path performs, and skip the entire
delayed_pic[] / POC reorder machinery.
- Suppress the SPS-driven has_b_frames clobber in
h264_field_start when the flag is set, so the per-slice
bitstream_restriction_flag re-pickup cannot reintroduce a
nonzero reorder buffer mid-stream.
This is a fork-only change required by the daedalus-v4l2 daemon's
one-frame-per-send_packet contract; upstream FFmpeg consumers that
expect display-order output remain untouched (flag default = off).
Refs reauktion/daedalus-v4l2#11 — substitution arc step 2 deblock
+ flag-restoration follow-up.
---
libavcodec/h264_slice.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index 97fab70..a7bfbd6 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1308,6 +1308,28 @@ static int h264_select_output_frame(H264Context *h)
cur->mmco_reset = h->mmco_reset;
h->mmco_reset = 0;
+ /* AV_CODEC_FLAG_LOW_DELAY restore (FFmpeg 8.x dropped the H.264
+ * decoder's low_delay path). Bypass the display-order DPB
+ * output queue: emit the just-decoded picture immediately, in
+ * decode order, one per send_packet. V4L2-stateless-style
+ * consumers (daedalus-v4l2 daemon, libva-v4l2-request-fourier)
+ * do their own POC-based reorder downstream and require this
+ * behaviour. */
+ if (h->avctx->flags & AV_CODEC_FLAG_LOW_DELAY) {
+ h->next_output_pic = cur;
+ h->next_outputed_poc = cur->poc;
+ h->frame_recovered |= cur->recovered;
+ cur->recovered |= h->frame_recovered & FRAME_RECOVERED_SEI;
+ if (!cur->recovered) {
+ if (!(h->avctx->flags & AV_CODEC_FLAG_OUTPUT_CORRUPT) &&
+ !(h->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
+ h->next_output_pic = NULL;
+ else
+ cur->f->flags |= AV_FRAME_FLAG_CORRUPT;
+ }
+ return 0;
+ }
+
if (sps->bitstream_restriction_flag ||
h->avctx->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
h->avctx->has_b_frames = FFMAX(h->avctx->has_b_frames, sps->num_reorder_frames);
@@ -1415,6 +1437,7 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl,
sps = h->ps.sps;
if (sps->bitstream_restriction_flag &&
+ !(h->avctx->flags & AV_CODEC_FLAG_LOW_DELAY) &&
h->avctx->has_b_frames < sps->num_reorder_frames) {
h->avctx->has_b_frames = sps->num_reorder_frames;
}
--
2.47.3
+5 -3
View File
@@ -24,7 +24,7 @@ _srcname=FFmpeg
_version='8.1' _version='8.1'
_commit='b57fbbe50c9b2656fad86a1a7eeabfd2b2a50935' # v4l2-request-n8.1 tip 2026-04-24 _commit='b57fbbe50c9b2656fad86a1a7eeabfd2b2a50935' # v4l2-request-n8.1 tip 2026-04-24
pkgver=8.1.r123329.b57fbbe pkgver=8.1.r123329.b57fbbe
pkgrel=8 # pkgrel=8H.264 luma-v deblock daedalus-fourier substitution (cycle 8, 2026-05-22) pkgrel=9 # pkgrel=9restore AV_CODEC_FLAG_LOW_DELAY for H.264 (2026-05-22)
epoch=2 epoch=2
# daedalus-fourier pin — first kernel substitution in libavcodec # daedalus-fourier pin — first kernel substitution in libavcodec
@@ -92,8 +92,9 @@ source=("git+https://github.com/Kwiboo/FFmpeg.git#commit=${_commit}"
'0002-nv15-to-p010-unpack.patch' '0002-nv15-to-p010-unpack.patch'
'0003-h264-idct4-daedalus-fourier.patch' '0003-h264-idct4-daedalus-fourier.patch'
'0004-h264-idct8-daedalus-fourier.patch' '0004-h264-idct8-daedalus-fourier.patch'
'0005-h264-deblock-luma-v-daedalus-fourier.patch') '0005-h264-deblock-luma-v-daedalus-fourier.patch'
sha256sums=('SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP') '0006-h264-restore-low-delay.patch')
sha256sums=('SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP' 'SKIP')
pkgver() { pkgver() {
cd "${_srcname}" cd "${_srcname}"
@@ -109,6 +110,7 @@ prepare() {
patch -Np1 -i "${srcdir}/0003-h264-idct4-daedalus-fourier.patch" patch -Np1 -i "${srcdir}/0003-h264-idct4-daedalus-fourier.patch"
patch -Np1 -i "${srcdir}/0004-h264-idct8-daedalus-fourier.patch" patch -Np1 -i "${srcdir}/0004-h264-idct8-daedalus-fourier.patch"
patch -Np1 -i "${srcdir}/0005-h264-deblock-luma-v-daedalus-fourier.patch" patch -Np1 -i "${srcdir}/0005-h264-deblock-luma-v-daedalus-fourier.patch"
patch -Np1 -i "${srcdir}/0006-h264-restore-low-delay.patch"
} }
build() { build() {
+3 -3
View File
@@ -14,9 +14,9 @@
# Sibling userspace package: ../daedalus-v4l2/build-deb.sh # Sibling userspace package: ../daedalus-v4l2/build-deb.sh
set -euo pipefail set -euo pipefail
UPSTREAM_COMMIT=5d8b4369e58ab947d1c56b1f718293c57c6065b5 UPSTREAM_COMMIT=872eec505eb91b561892d02a0526749348ddc121
PKGVER=0.1.0+r33+g5d8b436 PKGVER=0.1.0+r45+g872eec5
PKGREL=1 # reset for new upstream pin (5d8b436 — revert parking design); still carries the #64 multi-kernel postinst fix PKGREL=1 # reset for new upstream pin (872eec5 — PROTO_MAX_PAYLOAD 64 KiB -> 1 MiB, closes #19); lock-step with daedalus-v4l2 0.1.0+r45+g872eec5 REQUIRED
MODULE_NAME=daedalus_v4l2 MODULE_NAME=daedalus_v4l2
HERE=$(dirname "$(readlink -f "$0")") HERE=$(dirname "$(readlink -f "$0")")
+21
View File
@@ -1,3 +1,24 @@
daedalus-v4l2-dkms (0.1.0+r45+g872eec5-1) bookworm trixie; urgency=medium
* Bump to 872eec5 — picks up daedalus-v4l2 PR #20 (closes #19).
Wire-protocol cap DAEDALUS_PROTO_MAX_PAYLOAD raised from 64 KiB
to 1 MiB in include/daedalus_v4l2_proto.h. The kernel module
inherits the larger DAEDALUS_MAX_BITSTREAM via the same #define
and daedalus_fill_output_fmt now reports OUTPUT_MPLANE
sizeimage = ~1 MiB instead of 65484.
* Skips the r33 -> r45 commit range — between 5d8b436 and 872eec5
only one kernel/include change landed (the PROTO_MAX_PAYLOAD
bump above). The intervening daemon-only bumps (r37 / r39 /
r41 / r43) didn't touch kernel/ or include/ at all.
* Effective wire cap is min(kernel, daemon) — lock-step install
WITH daedalus-v4l2 0.1.0+r45+g872eec5 REQUIRED.
* Allocations (kmemdup / kmalloc on payload, vb2 plane backing)
are dynamic and sized per-payload at runtime; the bump only
sets the ceiling. KMALLOC_MAX_SIZE on aarch64 SLUB is several
MiB so 1 MiB is well within bounds.
-- Markus Fritsche <mfritsche@reauktion.de> Fri, 22 May 2026 21:00:00 +0000
daedalus-v4l2-dkms (0.1.0+r33+g5d8b436-1) bookworm trixie; urgency=medium daedalus-v4l2-dkms (0.1.0+r33+g5d8b436-1) bookworm trixie; urgency=medium
* Bump to 5d8b436 — reverts daedalus-v4l2 PRs #7 + #8. Kernel * Bump to 5d8b436 — reverts daedalus-v4l2 PRs #7 + #8. Kernel
+3 -3
View File
@@ -19,9 +19,9 @@ set -euo pipefail
# source tree we own in marfrit-packages. Headers + .pc files # source tree we own in marfrit-packages. Headers + .pc files
# come from ffmpeg-v4l2-request-fourier (installed by the CI # come from ffmpeg-v4l2-request-fourier (installed by the CI
# workflow before this script runs; see PKG_CONFIG_PATH below). # workflow before this script runs; see PKG_CONFIG_PATH below).
UPSTREAM_COMMIT=6e6dfa144da7bc7fa8be50c8da91d7d1c6132a2c UPSTREAM_COMMIT=872eec505eb91b561892d02a0526749348ddc121
PKGVER=0.1.0+r41+g6e6dfa1 PKGVER=0.1.0+r45+g872eec5
PKGREL=1 # reset for new upstream pin (6e6dfa1 — soname 62 via /opt/fourier) PKGREL=1 # reset for new upstream pin (872eec5 — PROTO_MAX_PAYLOAD 64 KiB -> 1 MiB, closes #19); lock-step with daedalus-v4l2-dkms 0.1.0+r45+g872eec5 REQUIRED
# daedalus-fourier pin. d87239d = marfrit/daedalus-fourier PR #1 merge # daedalus-fourier pin. d87239d = marfrit/daedalus-fourier PR #1 merge
# (install rules + pkg-config, enables this consumer to find_package # (install rules + pkg-config, enables this consumer to find_package
+43
View File
@@ -1,3 +1,46 @@
daedalus-v4l2 (0.1.0+r45+g872eec5-1) bookworm trixie; urgency=medium
* Bump to 872eec5 — picks up daedalus-v4l2 PR #20 (closes #19).
Wire-protocol cap DAEDALUS_PROTO_MAX_PAYLOAD raised from 64 KiB
to 1 MiB. DAEDALUS_MAX_BITSTREAM follows; daedalus_fill_output_fmt
now reports OUTPUT_MPLANE sizeimage = ~1 MiB instead of 65484.
libva-v4l2-request-fourier's S_FMT-driven OUTPUT-pool resize
finally succeeds; Firefox no longer falls off to libmozavcodec
SW when an H.264 slice exceeds 64 KiB (routine on any
720p+ stream).
* #define-only change in include/daedalus_v4l2_proto.h; struct
layout unchanged. But effective cap is min(kernel, daemon) —
lock-step install of this package WITH
daedalus-v4l2-dkms 0.1.0+r45+g872eec5 REQUIRED.
* Daemon-side allocations are dynamic (malloc-on-payload), so
the practical growth is one ~1 MiB read buffer per daemon
process at startup. Negligible on Pi 5 / 8 GB.
* Picks up the same r43 -> r45 transition as daedalus-v4l2-dkms
(which had been stuck at r33+g5d8b436 since the parking-design
revert because the kernel module didn't change in r37/r39/r41/r43).
-- Markus Fritsche <mfritsche@reauktion.de> Fri, 22 May 2026 21:00:00 +0000
daedalus-v4l2 (0.1.0+r43+g1d8f5af-1) bookworm trixie; urgency=medium
* Bump to 1d8f5af — picks up daedalus-v4l2 PR #18 (closes #17).
Daemon now drops degenerate (<4 byte) bitstreams at the REQ_DECODE
entry instead of letting avcodec_send_packet return
AVERROR_INVALIDDATA. Reply RESP_FRAME with status=
DAEDALUS_DECODE_NO_FRAME so libva's V4L2 surface pool stays
healthy.
* Fixes the Firefox YouTube avc1 pause→resume regression observed
on higgs: libva-v4l2-request-fourier flushes a 3-byte stub
(presumably a bare NAL start code) into OUTPUT_MPLANE at the
pause boundary; the old INVALIDDATA error path made Firefox
fall off to libmozavcodec SW for the rest of the session. With
this filter the daemon logs the sentinel as 'tiny bitstream 3
bytes — dropping as no-op' and the next real REQ_DECODE
proceeds normally.
* Wire protocol unchanged. No daedalus-v4l2-dkms bump needed.
-- Markus Fritsche <mfritsche@reauktion.de> Fri, 22 May 2026 17:30:00 +0000
daedalus-v4l2 (0.1.0+r41+g6e6dfa1-1) bookworm trixie; urgency=medium daedalus-v4l2 (0.1.0+r41+g6e6dfa1-1) bookworm trixie; urgency=medium
* Bump to 6e6dfa1 — daedalus-v4l2 PR #16. Daemon dlopens Kwiboo * Bump to 6e6dfa1 — daedalus-v4l2 PR #16. Daemon dlopens Kwiboo
@@ -0,0 +1,82 @@
From 0d1292ea99bc4e5fa2da438259fa01a2374e3e04 Mon Sep 17 00:00:00 2001
From: Markus Fritsche <mfritsche@reauktion.de>
Date: Fri, 22 May 2026 14:18:25 +0200
Subject: [PATCH] avcodec/h264: restore AV_CODEC_FLAG_LOW_DELAY semantics
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
FFmpeg 8.x dropped the H.264 decoder's low_delay path —
AV_CODEC_FLAG_LOW_DELAY no longer prevents
h264_select_output_frame from running the display-order DPB
output queue. V4L2-stateless-style consumers (daedalus-v4l2
daemon, libva-v4l2-request-fourier) that set the flag end up
seeing the 2-1-4-3 pair-swap pattern on B-frame streams again.
Restore the documented semantics:
- Early-exit at the top of h264_select_output_frame when the
flag is set: emit the just-decoded picture immediately as
next_output_pic, mirror the corruption / recovery-point
tracking the main path performs, and skip the entire
delayed_pic[] / POC reorder machinery.
- Suppress the SPS-driven has_b_frames clobber in
h264_field_start when the flag is set, so the per-slice
bitstream_restriction_flag re-pickup cannot reintroduce a
nonzero reorder buffer mid-stream.
This is a fork-only change required by the daedalus-v4l2 daemon's
one-frame-per-send_packet contract; upstream FFmpeg consumers that
expect display-order output remain untouched (flag default = off).
Refs reauktion/daedalus-v4l2#11 — substitution arc step 2 deblock
+ flag-restoration follow-up.
---
libavcodec/h264_slice.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index 97fab70..a7bfbd6 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1308,6 +1308,28 @@ static int h264_select_output_frame(H264Context *h)
cur->mmco_reset = h->mmco_reset;
h->mmco_reset = 0;
+ /* AV_CODEC_FLAG_LOW_DELAY restore (FFmpeg 8.x dropped the H.264
+ * decoder's low_delay path). Bypass the display-order DPB
+ * output queue: emit the just-decoded picture immediately, in
+ * decode order, one per send_packet. V4L2-stateless-style
+ * consumers (daedalus-v4l2 daemon, libva-v4l2-request-fourier)
+ * do their own POC-based reorder downstream and require this
+ * behaviour. */
+ if (h->avctx->flags & AV_CODEC_FLAG_LOW_DELAY) {
+ h->next_output_pic = cur;
+ h->next_outputed_poc = cur->poc;
+ h->frame_recovered |= cur->recovered;
+ cur->recovered |= h->frame_recovered & FRAME_RECOVERED_SEI;
+ if (!cur->recovered) {
+ if (!(h->avctx->flags & AV_CODEC_FLAG_OUTPUT_CORRUPT) &&
+ !(h->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
+ h->next_output_pic = NULL;
+ else
+ cur->f->flags |= AV_FRAME_FLAG_CORRUPT;
+ }
+ return 0;
+ }
+
if (sps->bitstream_restriction_flag ||
h->avctx->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
h->avctx->has_b_frames = FFMAX(h->avctx->has_b_frames, sps->num_reorder_frames);
@@ -1415,6 +1437,7 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl,
sps = h->ps.sps;
if (sps->bitstream_restriction_flag &&
+ !(h->avctx->flags & AV_CODEC_FLAG_LOW_DELAY) &&
h->avctx->has_b_frames < sps->num_reorder_frames) {
h->avctx->has_b_frames = sps->num_reorder_frames;
}
--
2.47.3
+8 -7
View File
@@ -33,13 +33,13 @@ FFMPEG_VERSION=8.1
# epoch 2 matches Debian's stock ffmpeg (currently 7:7.1.x in trixie); # epoch 2 matches Debian's stock ffmpeg (currently 7:7.1.x in trixie);
# +rfourier suffix to avoid colliding with upstream/Debian rebuilds. # +rfourier suffix to avoid colliding with upstream/Debian rebuilds.
PKGVER=2:${FFMPEG_VERSION}+rfourier+gb57fbbe PKGVER=2:${FFMPEG_VERSION}+rfourier+gb57fbbe
PKGREL=8 # pkgrel=8H.264 luma-v deblock daedalus-fourier substitution PKGREL=9 # pkgrel=9restore AV_CODEC_FLAG_LOW_DELAY semantics in the
# (cycle 8, non-intra bS<4 vertical luma). Stacks on cycles # H.264 decoder (FFmpeg 8.x dropped them). Fixes the 2-1-4-3
# 6/7 (IDCT 4x4 + 8x8). Wires H264DSPContext.v_loop_filter_luma # B-frame pair-swap that re-appeared in Firefox YouTube after
# through daedalus_recipe_dispatch_h264_deblock_luma_v. # the SONAME 61→62 jump (PR #75) silently neutered the
# ctx stays no-QPU until a separate change gates Vulkan init # daemon's ctx->flags |= AV_CODEC_FLAG_LOW_DELAY at
# on a feature flag; cycle-8 dispatch is NEON-by-recipe for # daemon/src/decoder.c:202. Substitution arc unchanged.
# now. (2026-05-22) # (2026-05-22)
# daedalus-fourier pin — first kernel substitution in libavcodec (cycle 6 # daedalus-fourier pin — first kernel substitution in libavcodec (cycle 6
# H.264 IDCT 4x4). Same SHA as the daedalus-v4l2 daemon already ships # H.264 IDCT 4x4). Same SHA as the daedalus-v4l2 daemon already ships
@@ -71,6 +71,7 @@ patch -Np1 -i "$HERE/0002-nv15-to-p010-unpack.patch"
patch -Np1 -i "$HERE/0003-h264-idct4-daedalus-fourier.patch" patch -Np1 -i "$HERE/0003-h264-idct4-daedalus-fourier.patch"
patch -Np1 -i "$HERE/0004-h264-idct8-daedalus-fourier.patch" patch -Np1 -i "$HERE/0004-h264-idct8-daedalus-fourier.patch"
patch -Np1 -i "$HERE/0005-h264-deblock-luma-v-daedalus-fourier.patch" patch -Np1 -i "$HERE/0005-h264-deblock-luma-v-daedalus-fourier.patch"
patch -Np1 -i "$HERE/0006-h264-restore-low-delay.patch"
# --- daedalus-fourier: fetch + build static .a with PIC, install to a # --- daedalus-fourier: fetch + build static .a with PIC, install to a
# per-build prefix; libavcodec.so links it into the shared object so # per-build prefix; libavcodec.so links it into the shared object so
+25
View File
@@ -1,3 +1,28 @@
ffmpeg-v4l2-request-fourier (2:8.1+rfourier+gb57fbbe-9) bookworm trixie; urgency=medium
* Add 0006-h264-restore-low-delay.patch — restore the documented
AV_CODEC_FLAG_LOW_DELAY semantics in the H.264 decoder. FFmpeg
8.x dropped the H.264 low_delay code path entirely; setting the
flag at avcodec_open2 no longer prevents the display-order DPB
output queue from running. Visible on Firefox YouTube as the
2-1-4-3 B-frame pair-swap, re-introduced silently by the
SONAME 61→62 jump in daedalus-v4l2 PR #16.
* h264_select_output_frame: early-exit when LOW_DELAY is set;
emit the just-decoded picture as next_output_pic, mirror the
corruption / recovery-point tracking, skip delayed_pic[] and
the POC reorder machinery entirely.
* h264_field_start: suppress the SPS-driven
has_b_frames = sps->num_reorder_frames clobber when LOW_DELAY
is set — without this the per-slice bitstream_restriction_flag
re-pickup would reintroduce a nonzero reorder buffer mid-
stream.
* Restores the same one-frame-per-send_packet contract the
daedalus-v4l2 daemon's decoder.c already relies on (the flag
is set unconditionally for H.264). No daemon side change.
* No SONAME change, no Depends change.
-- Markus Fritsche <mfritsche@reauktion.de> Fri, 22 May 2026 13:30:00 +0000
ffmpeg-v4l2-request-fourier (2:8.1+rfourier+gb57fbbe-8) bookworm trixie; urgency=medium ffmpeg-v4l2-request-fourier (2:8.1+rfourier+gb57fbbe-8) bookworm trixie; urgency=medium
* Add 0005-h264-deblock-luma-v-daedalus-fourier.patch — * Add 0005-h264-deblock-luma-v-daedalus-fourier.patch —