refactor(client-core/W8): split video.rs into flat decoder-backend siblings

Break the 1974-line pf-client-core/src/video.rs into flat sibling modules
(matching the crate's video_d3d11.rs / video_pyrowave.rs convention), leaving
video.rs as the contract + Decoder dispatch facade:
  - video_color.rs   : ColorDesc + csc_rows (the Y'CbCr->RGB matrix)
  - video_software.rs : the libavcodec/swscale SoftwareDecoder
  - video_vaapi.rs   : the Linux-only VAAPI/DRM-PRIME backend (mod is cfg(linux))
  - video_vulkan.rs  : the FFmpeg Vulkan Video backend
Every crate::video::X / video::X path stays byte-stable (ColorDesc + csc_rows
re-exported from video.rs; frame POD, VulkanDecodeDevice, QueueLock, Decoder,
decodable_codecs*, ffmpeg_codec_id, fourcc/drm_fourcc_for all stay in video.rs).
Code-driven placements: averr, AVERROR_EAGAIN, frame_is_keyframe stay in video.rs
(shared by all three decoders); DrmFrameGuard's field + drm_fourcc_for +
Software/Vaapi/VulkanDecoder ctors/decode became pub(crate) (sibling access);
the test module split three ways (software tests need private decoder internals).
Pure move; no behavior change.

Verified on Linux (home-worker-5): cargo clippy -p pf-client-core (default
[pyrowave] + --no-default-features, --all-targets -D warnings) + cargo test.
Windows verify BLOCKED environmentally: pf-client-core -> sdl3 build-from-source
-> CMake/CL.exe fails on winbox's non-ASCII home path (fails the baseline too,
independent of this split); the split's Windows surface (facade cfg(windows) bits
+ video_d3d11) is verbatim-preserved.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-07-17 14:06:57 +02:00
parent ffa63a74f2
commit 570ff504ad
6 changed files with 1154 additions and 1101 deletions
+243
View File
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//! VAAPI (libavcodec hwaccel) decode backend → DRM-PRIME dmabuf for the presenter. Linux-only.
use crate::video::{
averr, drm_fourcc_for, frame_is_keyframe, DmabufFrame, DmabufPlane, DrmFrameGuard,
AVERROR_EAGAIN,
};
use crate::video_color::ColorDesc;
use anyhow::{anyhow, bail, Result};
use ffmpeg_next as ffmpeg;
use std::ptr;
/// libavcodec offers the formats it can decode into; pick the VAAPI hw surface. Falling
/// back to the first (software) entry would silently decode on the CPU *and* break our
/// dmabuf mapping — return NONE instead so the error surfaces and the session demotes
/// to the software backend explicitly.
#[cfg(target_os = "linux")]
unsafe extern "C" fn pick_vaapi(
_ctx: *mut ffmpeg::ffi::AVCodecContext,
mut list: *const ffmpeg::ffi::AVPixelFormat,
) -> ffmpeg::ffi::AVPixelFormat {
unsafe {
while *list != ffmpeg::ffi::AVPixelFormat::AV_PIX_FMT_NONE {
if *list == ffmpeg::ffi::AVPixelFormat::AV_PIX_FMT_VAAPI {
return ffmpeg::ffi::AVPixelFormat::AV_PIX_FMT_VAAPI;
}
list = list.add(1);
}
}
ffmpeg::ffi::AVPixelFormat::AV_PIX_FMT_NONE
}
#[cfg(target_os = "linux")]
pub(crate) struct VaapiDecoder {
ctx: *mut ffmpeg::ffi::AVCodecContext,
hw_device: *mut ffmpeg::ffi::AVBufferRef,
packet: *mut ffmpeg::ffi::AVPacket,
frame: *mut ffmpeg::ffi::AVFrame,
}
// Single-owner pointers, only touched from the session pump thread.
#[cfg(target_os = "linux")]
unsafe impl Send for VaapiDecoder {}
#[cfg(target_os = "linux")]
impl VaapiDecoder {
pub(crate) fn new(codec_id: ffmpeg::codec::Id) -> Result<VaapiDecoder> {
use ffmpeg::ffi;
unsafe {
let mut hw_device: *mut ffi::AVBufferRef = ptr::null_mut();
let r = ffi::av_hwdevice_ctx_create(
&mut hw_device,
ffi::AVHWDeviceType::AV_HWDEVICE_TYPE_VAAPI,
ptr::null(),
ptr::null_mut(),
0,
);
if r < 0 {
bail!("no VAAPI device ({})", ffmpeg::Error::from(r));
}
// The negotiated codec's decoder id (av_codec_id maps 1:1 from ffmpeg::codec::Id).
let codec = ffi::avcodec_find_decoder(codec_id.into());
if codec.is_null() {
ffi::av_buffer_unref(&mut hw_device);
bail!("no {codec_id:?} decoder");
}
let ctx = ffi::avcodec_alloc_context3(codec);
(*ctx).hw_device_ctx = ffi::av_buffer_ref(hw_device);
(*ctx).get_format = Some(pick_vaapi);
(*ctx).flags |= ffi::AV_CODEC_FLAG_LOW_DELAY as i32;
(*ctx).thread_count = 1; // hwaccel: threads only add latency
// The presenter holds mapped surfaces PAST receive_frame (the paintable's
// current texture + the newest frame in flight each pin one until GDK's
// release func) — surfaces libavcodec doesn't know are missing from its
// fixed-size VAAPI pool. Without headroom the decoder can recycle a surface
// the renderer is still sampling (intermittent block corruption) or fail
// allocation under scheduling jitter.
(*ctx).extra_hw_frames = 4;
let r = ffi::avcodec_open2(ctx, codec, ptr::null_mut());
if r < 0 {
let mut ctx = ctx;
ffi::avcodec_free_context(&mut ctx);
let mut hw_device = hw_device;
ffi::av_buffer_unref(&mut hw_device);
bail!("avcodec_open2: {}", ffmpeg::Error::from(r));
}
Ok(VaapiDecoder {
ctx,
hw_device,
packet: ffi::av_packet_alloc(),
frame: ffi::av_frame_alloc(),
})
}
}
pub(crate) fn decode(&mut self, au: &[u8]) -> Result<Option<DmabufFrame>> {
use ffmpeg::ffi;
unsafe {
let r = ffi::av_new_packet(self.packet, au.len() as i32);
if r < 0 {
return Err(averr("av_new_packet", r));
}
ptr::copy_nonoverlapping(au.as_ptr(), (*self.packet).data, au.len());
let r = ffi::avcodec_send_packet(self.ctx, self.packet);
ffi::av_packet_unref(self.packet);
if r < 0 {
return Err(averr("send_packet", r));
}
let mut out = None;
loop {
let r = ffi::avcodec_receive_frame(self.ctx, self.frame);
if r == AVERROR_EAGAIN {
break;
}
if r < 0 {
return Err(averr("receive_frame", r));
}
out = Some(self.map_dmabuf()?); // newest wins; older guards drop here
ffi::av_frame_unref(self.frame);
}
Ok(out)
}
}
/// Map the VAAPI surface to DRM PRIME (zero copy) and lift the descriptor into a
/// `DmabufFrame`. The mapped frame keeps the surface alive via its buffer refs.
///
/// FFmpeg's VAAPI export uses `VA_EXPORT_SURFACE_SEPARATE_LAYERS`, so an NV12 surface
/// comes back as TWO layers (`R8` luma + `GR88` chroma), each one plane — NOT a single
/// `NV12` layer. The previous code took `layers[0]` only: GTK then saw an `R8`
/// single-plane texture with the chroma dropped, painting the screen green. The fix:
/// derive the COMBINED fourcc from the decoder's software pixel format (NV12 →
/// `DRM_FORMAT_NV12`) and flatten every plane across every layer in order (Y then UV).
unsafe fn map_dmabuf(&mut self) -> Result<DmabufFrame> {
use ffmpeg::ffi;
unsafe {
if (*self.frame).format != ffi::AVPixelFormat::AV_PIX_FMT_VAAPI as i32 {
bail!("decoder returned a software frame (no VAAPI surface)");
}
// The real pixel layout lives on the hardware frames context, not the
// DRM-PRIME layer formats (those are the per-plane R8/GR88 component formats).
let sw_format = {
let hwfc = (*self.frame).hw_frames_ctx;
if hwfc.is_null() {
bail!("VAAPI frame without a hardware frames context");
}
(*((*hwfc).data as *const ffi::AVHWFramesContext)).sw_format
};
let fourcc = drm_fourcc_for(sw_format)
.ok_or_else(|| anyhow!("unsupported VAAPI output format {sw_format:?}"))?;
let drm = ffi::av_frame_alloc();
(*drm).format = ffi::AVPixelFormat::AV_PIX_FMT_DRM_PRIME as i32;
let r = ffi::av_hwframe_map(drm, self.frame, ffi::AV_HWFRAME_MAP_READ as i32);
if r < 0 {
let mut drm = drm;
ffi::av_frame_free(&mut drm);
return Err(averr("av_hwframe_map", r));
}
let desc = (*drm).data[0] as *const ffi::AVDRMFrameDescriptor;
let guard = DrmFrameGuard(drm);
let d = &*desc;
if d.nb_layers < 1 || d.nb_objects < 1 {
bail!("DRM descriptor without layers/objects");
}
// Flatten planes across ALL layers, in declared order — the combined fourcc's
// plane order (Y, then UV for NV12) matches the layer order FFmpeg emits.
let mut planes = Vec::new();
for layer in &d.layers[..d.nb_layers as usize] {
for p in &layer.planes[..layer.nb_planes as usize] {
let obj = &d.objects[p.object_index as usize];
planes.push(DmabufPlane {
fd: obj.fd,
offset: p.offset as u32,
stride: p.pitch as u32,
});
}
}
// The whole surface shares one tiling modifier (one BO on radeonsi); GTK takes
// a single modifier for the texture.
let modifier = d.objects[0].format_modifier;
log_descriptor_once(d, sw_format, fourcc, modifier);
Ok(DmabufFrame {
width: (*self.frame).width as u32,
height: (*self.frame).height as u32,
fourcc,
modifier,
planes,
// SAFETY: `self.frame` is the live decoded AVFrame (unref'd only after
// this returns); plain CICP field reads.
color: ColorDesc::from_raw(self.frame),
keyframe: frame_is_keyframe(self.frame),
guard,
})
}
}
}
/// One-time dump of the DRM descriptor layout (objects, layers, planes, modifier) — so a
/// new client/driver combination's real layout is visible in the logs without a debugger.
#[cfg(target_os = "linux")]
fn log_descriptor_once(
d: &ffmpeg_next::ffi::AVDRMFrameDescriptor,
sw: ffmpeg_next::ffi::AVPixelFormat,
fourcc: u32,
modifier: u64,
) {
use std::sync::atomic::{AtomicBool, Ordering};
static ONCE: AtomicBool = AtomicBool::new(true);
if !ONCE.swap(false, Ordering::Relaxed) {
return;
}
let layers: Vec<(u32, i32)> = d.layers[..d.nb_layers.max(0) as usize]
.iter()
.map(|l| (l.format, l.nb_planes))
.collect();
tracing::info!(
sw_format = ?sw,
chosen_fourcc = format_args!("{:#010x}", fourcc),
nb_objects = d.nb_objects,
nb_layers = d.nb_layers,
?layers,
modifier = format_args!("{:#018x}", modifier),
"VAAPI dmabuf descriptor layout (first frame)"
);
}
#[cfg(target_os = "linux")]
impl Drop for VaapiDecoder {
fn drop(&mut self) {
use ffmpeg::ffi;
unsafe {
ffi::av_packet_free(&mut self.packet);
ffi::av_frame_free(&mut self.frame);
ffi::avcodec_free_context(&mut self.ctx);
ffi::av_buffer_unref(&mut self.hw_device);
}
}
}