Ethanfel
6573fa6e05
mpv embedding: - Replace wid/QOpenGLWidget with QOffscreenSurface + QOpenGLFramebufferObject + QPainter readback — works on Wayland/KDE without sub-surface compositing - Force desktop OpenGL 3.3 core profile before QApplication (fixes black output on GLES) - Timer-based render polling (16 ms) replaces signal-flood from mpv C thread; fixes playback animation and scrubbing preview - Fix AB-loop: set ab-loop-a/b to "no" on stop (0 means infinite in mpv) Timeline: - Full redesign: time ruler with adaptive major/minor ticks, playhead triangle handle, selection region with edge lines, numbered marker badges - Height 160 px; layout collapsed from 4 rows to 2 below timeline - Markers appear immediately on export (optimistic update before ffmpeg finishes) - Right-click marker → context menu to delete from DB Hotkeys: - Replace keyPressEvent with QShortcut(ApplicationShortcut) so keys work regardless of focused widget; MpvWidget gets NoFocus policy Export: - WebP: switch lossless→lossy quality 85, compression_level 1 (~10x faster) - Add -threads 0 for full CPU utilisation during decode/filter - Remember last export folder across sessions via QSettings Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
47 lines
2.1 KiB
Markdown
47 lines
2.1 KiB
Markdown
# 8-cut Design
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## Overview
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A Linux desktop tool for dropping a video clip, setting a start point on a timeline, and exporting exactly 8 seconds to a numbered output file.
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## Stack
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- **Python + PyQt6** — native desktop window, drag & drop, custom timeline widget
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- **python-mpv** — embedded video playback with audio, frame-accurate seeking, AB loop for 8s preview
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- **ffmpeg** — export via subprocess, always re-encodes to guarantee exactly 8s with no freeze frames
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## Layout
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Single window, top to bottom:
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1. Drop zone / loaded file path display
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2. mpv video embed (preview)
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3. Custom timeline widget with draggable cursor
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4. Playback controls + cursor position display
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5. Export controls: base name input, folder picker, next filename preview, Export button
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## Behavior
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- **Drag & drop** a video file onto the window to load it
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- **Timeline**: click or drag to reposition cursor; shows current frame when paused
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- **Play 8s**: mpv seeks to cursor position, plays 8 seconds, loops back using mpv AB-loop (`ab-loop-a` = cursor, `ab-loop-b` = cursor + 8s)
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- **Pause**: shows current frame at cursor position
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- **Export**: runs ffmpeg in a QThread (non-blocking UI)
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- Command: `ffmpeg -ss {start} -i {input} -t 8 -c:v libx264 -c:a aac {output}`
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- Output: `{folder}/{basename}_{NNN:03d}.mp4`
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- Counter auto-increments after each successful export
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- Counter resets if base name or folder changes
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## Architecture
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Single file `main.py` (~300-400 lines):
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- `MainWindow(QMainWindow)` — owns all state: file path, cursor (seconds), base name, output folder, export counter
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- `TimelineWidget(QWidget)` — custom `paintEvent` draws bar + cursor line; `mousePressEvent`/`mouseMoveEvent` for scrubbing
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- `MpvWidget(QWidget)` — embeds mpv using window ID (`wid`), exposes `load(path)`, `seek(t)`, `play_loop(a, b)`, `pause()`
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- `ExportWorker(QThread)` — runs ffmpeg subprocess, emits `finished(path)` or `error(msg)` signal
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## Export guarantees
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Always re-encode (never stream copy) to avoid freeze frames caused by keyframe misalignment at the cut point. Output is always exactly 8.000 seconds.
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