HDR-to-SDR-Converter v.25.0

v25.0

Added

• Compare tone-mapping methods dialog: Visual side-by-side comparison of up to 18 GPU (libplacebo) and CPU (zscale + tonemap) curve × gamut combinations (Perceptual, Relative, Clip) on any frame from the source video, with an interactive timeline frame strip, 5-second test video clip rendering, and one-click ✓ Apply to conversion.
• Dolby Vision & HDR10+ support: Automatic detection of Dolby Vision (Profile 5, Profile 7, Profile 8) and HDR10+ dynamic metadata, native Profile 5 ICtCp reshaping via libplacebo, and ST2094-40 / ST2094-10 dynamic tone-mapping curves.
• Pro colour & image filters: Interactive 2D Brightness × Saturation pad, Colour temperature (Cool ↔ Warm) slider, Denoise (hqdn3d / nlmeans), Deband (gradfun), Sharpen (unsharp), 10-bit HDR Auto-crop, and Subtitle burn-in.
• Crash-safe conversion resume: Interrupted conversions are tracked automatically and can be resumed from the last completed keyframe segment with seamless segment splicing and output verification.
• Mini mode: Compact drag-and-drop launcher window with one-tap Fast, Optimal, and Best quality presets and live progress tracking.
• Settings & Theme Customizer (Ctrl+,): Full customization window with Light, Dark, and Neon palettes, custom gradient stops, background patterns, and adjustable card/button corner rounding.
• Intel QSV hardware encoding: Added h264_qsv, hevc_qsv, and av1_qsv alongside NVIDIA NVENC, AMD AMF, and CPU encoders.
• Post-conversion power actions: Option to do nothing, close the app, put the PC to sleep, or shut down after the queue finishes, plus toggles to keep the PC and display awake during conversion.
• SHA-256 verified portable tools: Added Stable and Latest download channels for portable FFmpeg and HandBrakeCLI with automatic SHA-256 checksum verification.
• 31 interface languages: Bundled complete localization files in i18n/.

Changed

• Modular hdr2sdr/ package architecture: Split the monolithic hdr_to_sdr_gui_qt.py script into hdr2sdr/{core,runtime,i18n,theme,ui} with a pure-Python core/ layer and an automated pytest test suite, while keeping python hdr_to_sdr_gui_qt.py and python -m hdr2sdr entry points compatible.
• Matroska (MKV) subtitle handling: Automatically converts MP4 mov_text timed-text subtitle streams to SRT (-c:s:N srt) when outputting to .mkv, while copying all other subtitle and audio streams untouched.
• Empty-state UI & Live Preview: Source analysis and Live preview panels remain permanently visible with stable heights; added an interactive timeline frame strip under Live Preview.

Fixed

• SVT-AV1 Bitrate mode: Removed unsupported -maxrate and -bufsize flags when building libsvtav1 bitrate commands.
• 10-bit HDR Auto-crop: Added format=yuv420p before cropdetect=24:2:0 so black bars are accurately detected on 10-bit HDR sources.
• HandBrakeCLI 10-bit H.264 & multi-pass: Updated --two-pass to --multi-pass and set --encoder-profile high10 for x264_10bit.
• Test clip & resume audio/video sync: Placed -ss 0 after -i to reset stream-copied audio/subtitle timestamps on 5-second test clips and resumed segments.
• NVENC preflight check: Increased the synthetic probe frame size from 128x128 to 256x256 to avoid false NVENC minimum-dimension rejections.
• GPU fallback state reset: Cleared libplacebo fallback flags when starting a new conversion or changing the tone-mapping curve manually.

HDR-to-SDR-Video-Converter

v2.2 — Changes

Fixed

• Audio dropped when switching tracks mid-playback on multi-audio/subtitle HDR/DV files (VLC/MPC) — fixed interleaving of copied streams
• FFmpeg portable installer no longer misses libplacebo/Vulkan (switched source, GPU tonemap curves now actually work)
• Orphaned conversion-history dialog reconnected (right-click on Output button)
• Tone-mapping tooltips and ~20 other hardcoded UI strings now properly localized (previously always English regardless of language setting)
• fix(i18n): wire tone-mapping tooltip descriptions (TONEMAP_INFO) through the translator — previously always shown in English regardless of interface language
• fix(i18n): sync tonemap_info_* strings in en.json with current source text (drift had silently broken existing translations)
• fix(i18n): add missing tonemap_info_spline translation key
• fix(i18n): translate ~20 other hardcoded tooltips (queue list, output/history button, analyze, preview expand/save, test clip controls, container MKV/MP4, install/update button, tray icon, dark/light mode)
• fix(i18n): dynamic test-clip button tooltips (render/cancel/ready states) now translate correctly instead of resetting to English at runtime
• feat(i18n): add translations for all newly wired tooltip strings (other languages fall back to English until translated)

Added

• Intel QuickSync (QSV) hardware encoding support (FFmpeg + HandBrakeCLI)
• HDR metadata panel (MaxCLL/MaxFALL, mastering display range, Dolby Vision profile, HDR10+ detection)
• Cross-platform completion notifications (system tray)
• "Check for updates" button — checks app + FFmpeg + HandBrakeCLI, offers to update either/both
• Spline tonemap curve
• Configurable test-clip duration, now includes all audio/subtitle tracks
• Russian translations for new tooltip strings

Changed

• Merged "Output"/"Open output folder"/"History" buttons into one
• Renamed GPU tonemap curve labels (details moved to tooltips)
• Activity log no longer auto-opens on conversion start

HDR-to-SDR-Video-Converter

• UI update
• Package conversion
• Saturation Trim
• MP4, MKV container
• else