mlt-7.38.0

[Bruce Dubbs]

New minor version.

[Joe Locash]

Version 7.38.0

Framework
  - Added dynamic hash table for `mlt_properties` for better performance.
  - Fixed memory corruption in `mlt_pool`.
  - Added warning on file open failure when parsing in `mlt_properties`. 

Modules
  - Added `hwaccel_scale` filter with preview scaling (scale_vaapi, scale_vulkan
, scale_d3d11, scale_vt (macOS)).
    This adds an environment variable `MLT_AVFORMAT_HWACCEL_PPS` to provide a
    limiter to hwaccel because transfering uncompressed video between memory
    CPU and GPU memory is heavy.
    PPS = maximum pixels per second. Anything over it skips hwaccel. 
  - Added *basic* support for **OpenFX** *filter* plugins.
    OpenFX has many features. This is a summary of what is NOT yet included:
    - GPU rendering
    - exotic parameter types: Integer2D, Integer3D, Double3D, Custom, Bytes, Pag
e, PushButton
    - plugin-driven keyframe animation; but MLT-driven does work
    - tile-, slice-, or frame-based multi-threading (only plugin internal thread
ing)
    - multi-resolution
    - temporal clip access
    - overlays & dialogs
    - timeline queries (e.g. `getTime()`)
    - generator, transition, retimer
    - parametric curves
  - Added `lut` parameter to `avformat` producer.
  - Added `attached_pic` property to `avformat` consumer.
  - Added `movit.overlay_blend` video filter.
  - Added `compositing` property to `movit.overlay` transition.
  - Added constant-power crossfade to `mix` audio transition.
  - Added rounded corner support for `rect` in `kdenlivetitle`.
  - Added typewriter properties to `subtitle` filter.
  - Added underline and strikethrough to the `text` and `qtext` filters.
  - Changed `qtext` `style` property to support family named styles.
  - Added anchor point support for arbitrary rotations in `qtblend`.
  - Allow relative paths for images in `kdenlivetitle`.
  - Updated Glaxnimate module to version 0.6.0.
  - Switched to `QImage` scaling when downscaling in `qtblend`.
  - Deprecated `obscure` and `watermark` filters.
  - Install the jackrack module's blacklist files.
  - Fixed subtitle stream type metadata.
  - Fixed mutex initialization in `avformat` no-validate mode.
  - Fixed crash when using `linearblend` deinterlacer.
  - Fixed black bar with HEVC hwaccel decode and scale on Windows.
  - Fixed crash with hardware scaler and interlaced video.
  - Fixed converting 8-bit full to limited range with hwaccel.
  - Fixed alpha in 12-bit ProRes with alpha.
  - Fixed `movit` linear color not matching CPU filters.
  - Fixed `multi` consumer making extra linear color conversions.
  - Fixed regression writing raw FLAC.
  - Fixed `qtblend` filter returning unexpectedly large frames.
  - Fixed `qtext` outline encroaching on fill color.
  - Fixed wrong last+ frame when `eof=loop` in Glaxnimate.
  - Fixed `brightness` filter on track below a clip with transparency.

Other
  - Fixed crash during exit cleanup in `melt`.
  - Continued build improvements for MSVC.
  - A lot of metadata fixes and improvements.
  - Many fixes to API documentation.
  - Added C++ and Python to the API docs.
  - Added two 10-bit VP9 encoding presets.

Fixed at 57bad1b248.