Files
siftlode/backend/app/downloads/edit.py
T
peter cae5702fbb fix(downloads): address code-review findings on the R2.5 mini-epic
- redownload: never clobber a co-held (deduped) asset. Drop the force-reset-to-pending;
  _release_asset already deletes+recreates a solo asset (genuine re-fetch), while a shared
  ready asset is left intact and the re-queued job re-points to it via _finish_from_cache —
  so one user's re-download can't delete another's file mid-serve (finding #1).
- redownload: reset queue_pos to the tail so a re-download doesn't front-run newer queued
  jobs on the worker's `ORDER BY queue_pos` claim (finding #3). Made service.next_queue_pos public.
- formats: video-only mp4 selector prefers every video-only option before any progressive
  `best`, so a "Video only" download stays audio-free whenever a video-only stream exists (#2).
- titles: a title that is only the engagement prefix no longer resurrects the stripped stats
  (return the stripped text / empty, not the raw) (#4).
- worker: probe the file's duration when yt-dlp gave none, so a long re-encode shows real
  progress instead of a frozen 0% (#5); tighten the ensure_browser_playable docstring to its
  actual mp4-profile scope (#6).
2026-07-22 02:21:05 +02:00

444 lines
18 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
"""Video editor (phase 2): per-user trim/crop derivatives via ffmpeg.
An edit derives a NEW per-user clip from an already-downloaded ready asset. It is never shared-
cached across users (the cache key embeds the user id), so it fully counts against the owner's
quota — but it still rides the same `MediaAsset`/`DownloadJob`/worker machinery as a download,
with the worker branching on the asset's `source_kind` to run ffmpeg instead of yt-dlp.
* trim, fast → stream copy (`-c copy`), instant, no quality loss, cuts SNAP to keyframes
(the in/out point can be off by a second or two)
* trim, accurate → re-encode (libx264 + aac), frame-accurate; cost scales with CLIP length
(the `-ss` seeks first), so a short clip is cheap even from a long source
* crop (± trim) → always re-encode (a filter can't be stream-copied), frame-accurate
`edit_spec = {trim?: {start_s, end_s}, crop?: {x, y, w, h}, accurate?: bool}`. `accurate` is the
per-edit user choice for a trim-only cut (ignored when a crop forces a re-encode anyway). `split`
is a frontend concept: the
UI fans a split out into N trim jobs, so there is one output file per job here.
Also builds the editor **filmstrip** — a single tiled sprite of the source video used as a visual
scrub track. Cached on the source asset's `storyboard_path` (reserved in phase 1) and reusable
for a player hover-preview later.
"""
import hashlib
import json
import logging
import math
import subprocess
from pathlib import Path
log = logging.getLogger("siftlode.edit")
class EditAborted(Exception):
"""Raised by run_ffmpeg when the job was paused/canceled mid-encode."""
# --- edit spec ------------------------------------------------------------------------------
def normalize_edit_spec(spec: dict | None) -> dict:
"""Canonicalize a raw edit spec: clamp/round trim, coerce crop to ints, drop empties.
The result is what gets hashed (so two equivalent specs share a cache row) and stored."""
spec = spec or {}
out: dict = {}
# Crop applies to both a single trim and a multi-segment join.
crop = spec.get("crop") or {}
if crop:
try:
c = {k: int(round(float(crop[k]))) for k in ("x", "y", "w", "h")}
except (KeyError, TypeError, ValueError):
c = None
if c and c["w"] > 0 and c["h"] > 0 and c["x"] >= 0 and c["y"] >= 0:
out["crop"] = c
# Multi-segment JOIN (cut-list → one concatenated file). Takes precedence over `trim`.
segs = spec.get("segments")
if isinstance(segs, list) and segs:
norm: list[dict] = []
for s in segs:
try:
st = max(0.0, float((s or {}).get("start_s") or 0.0))
end_raw = (s or {}).get("end_s")
if end_raw is None:
continue
en = float(end_raw)
except (TypeError, ValueError):
continue
if en > st:
norm.append({"start_s": round(st, 3), "end_s": round(en, 3)})
norm.sort(key=lambda x: x["start_s"])
if norm:
out["segments"] = norm
# A join always chooses a codec path: accurate=filter-concat re-encode,
# fast=demuxer-concat stream-copy (keyframe-snapped).
out["accurate"] = bool(spec.get("accurate", True))
return out
# Single TRIM (one output file; the frontend fans a "separate" split out into N of these).
trim = spec.get("trim") or {}
if trim:
# Guard the numeric coercion like the crop/segments branches do — a malformed value must
# drop the trim (→ empty spec → 400 EditError), not raise an unhandled 500.
try:
start = max(0.0, float(trim.get("start_s") or 0.0))
end_raw = trim.get("end_s")
end = float(end_raw) if end_raw is not None else None
except (TypeError, ValueError):
start, end = 0.0, None
t: dict = {"start_s": round(start, 3)}
if end is not None and end > start:
t["end_s"] = round(end, 3)
# A trim with only a start (open-ended) is valid (cut to the end).
if t.get("start_s") or "end_s" in t:
out["trim"] = t
# `accurate` only changes behaviour for a trim-only cut (a crop always re-encodes). Default to
# frame-accurate — an editor should cut where you asked; the user opts into fast/keyframe.
if out.get("trim") and "crop" not in out:
out["accurate"] = bool(spec.get("accurate", True))
return out
def edit_sig(spec: dict) -> str:
"""Stable 24-char signature of a (normalized) edit spec — the per-user cache identity."""
payload = json.dumps(normalize_edit_spec(spec), sort_keys=True, separators=(",", ":"))
return hashlib.sha256(payload.encode("utf-8")).hexdigest()[:24]
def has_crop(spec: dict) -> bool:
return bool(spec.get("crop"))
def needs_reencode(spec: dict) -> bool:
"""A crop always re-encodes; a trim re-encodes only when the user asked for an accurate cut."""
return bool(spec.get("crop")) or bool(spec.get("accurate"))
def clip_duration(spec: dict, source_duration: int | None) -> int | None:
"""Duration of the derived clip (seconds), for display + progress totals."""
segs = spec.get("segments")
if segs:
return max(0, round(sum(s["end_s"] - s["start_s"] for s in segs)))
trim = spec.get("trim")
if not trim:
return source_duration
start = trim.get("start_s") or 0.0
end = trim.get("end_s")
if end is None:
end = source_duration
if end is None:
return None
return max(0, round(end - start))
# --- ffmpeg: trim / crop --------------------------------------------------------------------
def build_edit_cmd(src: Path, dest: Path, spec: dict, out_ext: str) -> list[str]:
"""ffmpeg command for a trim/crop edit. `-progress pipe:1` streams machine-readable progress.
Trim uses fast input seek (`-ss` before `-i`) + `-t duration`, which is unambiguous across
ffmpeg versions. Trim-only stream-copies; a crop forces a re-encode (a filter can't be
stream-copied)."""
trim = spec.get("trim") or {}
start = trim.get("start_s") or 0.0
end = trim.get("end_s")
crop = spec.get("crop")
reencode = needs_reencode(spec)
cmd = [
"ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostdin",
"-progress", "pipe:1", "-nostats",
]
if start:
cmd += ["-ss", f"{start:.3f}"]
cmd += ["-i", str(src)]
if end is not None:
dur = end - start
if dur > 0:
cmd += ["-t", f"{dur:.3f}"]
if reencode:
# Input -ss + re-encode is frame-accurate (decodes from the prior keyframe, discards up to
# the exact cut). A crop adds the filter; an accurate trim re-encodes with no filter.
if crop:
cmd += ["-vf", f"crop={crop['w']}:{crop['h']}:{crop['x']}:{crop['y']}"]
cmd += [
"-c:v", "libx264", "-preset", "veryfast", "-crf", "20",
"-c:a", "aac", "-b:a", "192k",
]
else:
cmd += ["-c", "copy", "-avoid_negative_ts", "make_zero"]
if out_ext in ("mp4", "m4a", "mov"):
cmd += ["-movflags", "+faststart"]
cmd += [str(dest)]
return cmd
def build_concat_plan(src: Path, dest: Path, spec: dict, out_ext: str, staging: Path):
"""Plan a multi-segment JOIN (cut-list → one file). Returns (cmd, prep_files) where prep_files
maps a path → text content the worker must write before running (a concat list, if any).
* accurate/crop → filter_complex trim+concat, frame-accurate re-encode
* fast → concat demuxer with per-segment inpoint/outpoint, stream-copy
(keyframe-snapped, like the fast single trim)"""
segs: list[dict] = spec["segments"]
crop = spec.get("crop")
prep: dict[Path, str] = {}
head = [
"ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostdin",
"-progress", "pipe:1", "-nostats",
]
if needs_reencode(spec):
cropf = f",crop={crop['w']}:{crop['h']}:{crop['x']}:{crop['y']}" if crop else ""
parts, labels = [], []
for i, s in enumerate(segs):
st, en = s["start_s"], s["end_s"]
parts.append(f"[0:v]trim=start={st}:end={en},setpts=PTS-STARTPTS{cropf}[v{i}]")
parts.append(f"[0:a]atrim=start={st}:end={en},asetpts=PTS-STARTPTS[a{i}]")
labels.append(f"[v{i}][a{i}]")
parts.append(f"{''.join(labels)}concat=n={len(segs)}:v=1:a=1[v][a]")
cmd = head + [
"-i", str(src), "-filter_complex", ";".join(parts),
"-map", "[v]", "-map", "[a]",
"-c:v", "libx264", "-preset", "veryfast", "-crf", "20", "-c:a", "aac", "-b:a", "192k",
]
else:
listp = staging / "concat.txt"
lines = []
for s in segs:
lines.append(f"file '{src.as_posix()}'")
lines.append(f"inpoint {s['start_s']}")
lines.append(f"outpoint {s['end_s']}")
prep[listp] = "\n".join(lines) + "\n"
cmd = head + ["-f", "concat", "-safe", "0", "-i", str(listp), "-c", "copy"]
if out_ext in ("mp4", "m4a", "mov"):
cmd += ["-movflags", "+faststart"]
cmd += [str(dest)]
return cmd, prep
def _parse_out_time(line: str) -> float | None:
"""Parse a `-progress` line into elapsed output seconds."""
if line.startswith("out_time_us="):
try:
return int(line.split("=", 1)[1]) / 1_000_000
except ValueError:
return None
if line.startswith("out_time_ms="): # (some builds mislabel this as microseconds)
try:
return int(line.split("=", 1)[1]) / 1_000_000
except ValueError:
return None
return None
def run_ffmpeg(cmd, total_s, on_progress, should_cancel) -> None:
"""Run an ffmpeg edit, reporting 0–100 progress and honouring cooperative cancel.
Raises EditAborted if should_cancel() turns True mid-run, RuntimeError on a nonzero exit."""
proc = subprocess.Popen(
cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True, bufsize=1
)
try:
assert proc.stdout is not None
for line in proc.stdout:
line = line.strip()
if should_cancel():
proc.terminate()
try:
proc.wait(timeout=5)
except subprocess.TimeoutExpired:
proc.kill()
raise EditAborted
secs = _parse_out_time(line)
if secs is not None and total_s:
on_progress(max(0.0, min(99.0, secs * 100.0 / total_s)))
finally:
if proc.stdout:
proc.stdout.close()
ret = proc.wait()
if ret != 0:
err = (proc.stderr.read() if proc.stderr else "") or ""
raise RuntimeError(f"ffmpeg failed ({ret}): {err[:300]}")
# --- ffmpeg: universal browser playability --------------------------------------------------
# A downloaded file must play in EVERY browser, whatever the source shipped. Universal = H.264
# video + AAC/MP3 audio in an mp4 container: H.264 is the only video codec all browsers decode
# (VP9/AV1 fail on Safari/iOS; HEVC fails on Chrome/Firefox), and mp4/AAC is the safe pairing.
# Anything else is fixed post-download: re-encode the offending stream(s), or just remux when the
# codecs are already fine but the container isn't.
_BROWSER_SAFE_VCODEC = ("h264",)
_BROWSER_SAFE_ACODEC = ("aac", "mp3")
def probe_codecs(path: Path) -> tuple[str | None, str | None]:
"""Return (video_codec, audio_codec) lowercased via one ffprobe call; None for a missing
stream or if ffprobe fails (a failed probe is treated as 'leave it alone' upstream)."""
try:
out = subprocess.run(
["ffprobe", "-v", "error", "-show_entries", "stream=codec_type,codec_name",
"-of", "default=nw=1", str(path)],
capture_output=True, text=True, timeout=30, check=True,
).stdout.lower()
except (subprocess.TimeoutExpired, subprocess.CalledProcessError, OSError):
return None, None
vcodec = acodec = None
ctype = None
for line in out.splitlines():
if line.startswith("codec_type="):
ctype = line.split("=", 1)[1].strip()
elif line.startswith("codec_name="):
name = line.split("=", 1)[1].strip() or None
if ctype == "video" and vcodec is None:
vcodec = name
elif ctype == "audio" and acodec is None:
acodec = name
return vcodec, acodec
def probe_duration(path: Path) -> int:
"""Media duration in whole seconds via ffprobe, or 0 if unknown — a progress denominator for a
re-encode when the yt-dlp info dict carried no `duration` (some URL/live extractions)."""
try:
out = subprocess.run(
["ffprobe", "-v", "error", "-show_entries", "format=duration",
"-of", "default=nw=1:nk=1", str(path)],
capture_output=True, text=True, timeout=30, check=True,
).stdout.strip()
return int(float(out)) if out else 0
except (subprocess.TimeoutExpired, subprocess.CalledProcessError, OSError, ValueError):
return 0
def browser_transcode_flags(vcodec: str | None, acodec: str | None, is_mp4: bool) -> tuple[bool, bool, bool]:
"""Decide what (if anything) makes a file universally browser-playable. Returns
(needs_change, reencode_video, reencode_audio). needs_change=False => already H.264 + AAC/MP3
in mp4. A None codec (no such stream, or a failed probe) is never re-encoded."""
rv = bool(vcodec) and vcodec not in _BROWSER_SAFE_VCODEC
ra = bool(acodec) and acodec not in _BROWSER_SAFE_ACODEC
return (rv or ra or not is_mp4), rv, ra
def build_browser_safe_cmd(src: Path, dest: Path, reencode_video: bool, reencode_audio: bool) -> list[str]:
"""ffmpeg command that lands `src` as a browser-safe mp4 (faststart): re-encode only the
stream(s) that need it (libx264 / aac), stream-copy the rest, always into mp4. `-progress
pipe:1` streams machine-readable progress for run_ffmpeg."""
cmd = [
"ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostdin",
"-progress", "pipe:1", "-nostats", "-i", str(src),
]
cmd += ["-c:v", "libx264", "-preset", "veryfast", "-crf", "20"] if reencode_video else ["-c:v", "copy"]
cmd += ["-c:a", "aac", "-b:a", "192k"] if reencode_audio else ["-c:a", "copy"]
cmd += ["-movflags", "+faststart", str(dest)]
return cmd
# --- filmstrip (editor scrub track) ---------------------------------------------------------
_SB_COLS = 12
_SB_TILE_W = 160
def storyboard_geometry(duration_s: int | None) -> dict:
"""Deterministic sprite geometry for a source duration (so meta is recomputable, unstored).
~1 frame / 5 s, clamped to fill a 12-wide grid of 24–120 tiles."""
dur = max(1, int(duration_s or 1))
count = max(24, min(120, round(dur / 5)))
rows = math.ceil(count / _SB_COLS)
count = _SB_COLS * rows # fill the grid exactly
return {
"cols": _SB_COLS,
"rows": rows,
"count": count,
"interval_s": dur / count,
"tile_w": _SB_TILE_W,
}
def build_storyboard_cmd(src: Path, dest: Path, duration_s: int | None, geom: dict) -> list[str]:
"""One-pass tiled sprite. fps picks `count` frames evenly across the whole clip."""
dur = max(1, int(duration_s or 1))
fps = geom["count"] / dur
vf = f"fps={fps:.6f},scale={_SB_TILE_W}:-2,tile={geom['cols']}x{geom['rows']}"
return [
"ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostdin",
"-i", str(src), "-frames:v", "1", "-q:v", "5", "-vf", vf, str(dest),
]
def build_poster_cmd(src: Path, dest: Path, at_s: float) -> list[str]:
"""Grab one representative frame as a poster JPEG. `-ss` before `-i` seeks fast."""
return [
"ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostdin",
"-ss", f"{max(0.0, at_s):.3f}", "-i", str(src),
"-frames:v", "1", "-q:v", "3", "-vf", "scale=640:-2", str(dest),
]
def ensure_poster(asset, download_root: str, timeout_s: int = 30) -> str | None:
"""Generate a poster frame for a ready asset that has no thumbnail (e.g. a direct media URL
like a reddit HLS manifest, which yt-dlp can't get a thumbnail for). Written as the media's
`<base>.jpg` sidecar — so Plex uses it too and `delete_asset_files` cleans it up — and returned
as a rel path (or None on failure). Best-effort + time-bounded; a few seconds in (or 10% of a
short clip) dodges black intro frames."""
if not asset.rel_path:
return None
root = Path(download_root)
src = root / asset.rel_path
if not src.exists():
return None
rel = str(Path(asset.rel_path).with_suffix(".jpg"))
dest = root / rel
if dest.exists():
return rel
at = min(3.0, (asset.duration_s or 10) * 0.1)
try:
subprocess.run(build_poster_cmd(src, dest, at), capture_output=True, timeout=timeout_s, check=True)
except (subprocess.TimeoutExpired, subprocess.CalledProcessError, OSError) as exc:
log.info("poster gen skipped for asset %s: %s", asset.id, str(exc)[:120])
return None
return rel if dest.exists() else None
def ensure_storyboard(asset, download_root: str, timeout_s: int = 90) -> dict | None:
"""Return the filmstrip meta for a ready source asset, generating the sprite on first use.
Best-effort + time-bounded: for a very long/high-res source the one-pass decode can be slow,
so it's capped by `timeout_s`; on timeout/failure we return None and the editor falls back to
a plain timeline (no filmstrip). Caches the sprite path on `asset.storyboard_path`.
Returns None (caller should NOT commit) if generation didn't happen; otherwise a meta dict and
sets `asset.storyboard_path` (caller commits)."""
if not asset.rel_path:
return None
geom = storyboard_geometry(asset.duration_s)
root = Path(download_root)
rel = f".storyboards/asset-{asset.id}.jpg"
dest = root / rel
if asset.storyboard_path and (root / asset.storyboard_path).exists():
return {**geom, "rel": asset.storyboard_path}
src = root / asset.rel_path
if not src.exists():
return None
dest.parent.mkdir(parents=True, exist_ok=True)
cmd = build_storyboard_cmd(src, dest, asset.duration_s, geom)
try:
subprocess.run(cmd, capture_output=True, timeout=timeout_s, check=True)
except (subprocess.TimeoutExpired, subprocess.CalledProcessError, OSError) as exc:
log.info("storyboard gen skipped for asset %s: %s", asset.id, str(exc)[:120])
return None
if not dest.exists():
return None
asset.storyboard_path = rel # caller commits
return {**geom, "rel": rel}