v6.26.1 released

Apr 10, 2021

You can download it from GitHub.

This is the last planned release of major version 6. Version 7 will be released soon and introduce some minor API breakage while removing deprecations. The main new feature in this version is hardware-accellerated decoding! However, this is a basic implementation: It always returns the uncompressed video to the CPU memory with no pipelining to filters. Even when coupled with hardware encoding in the avformat consumer it must transfer the video. Also, there is no automatic software/CPU fallback and no resource management.


  • Added support for hwaccel query string parameter to the avformat producer. It accepts the following values:
    vaapi (Linux/BSD), cuda (Linux), videotoolbox (macOS), d3d11va (Windows), dxva2 (Windows)
    The query string delimiter is a backslash followed by a question mark: \?. The backslash prevents interpreting the question mark from being a part of the file name. You must preface the file name with either avformat: or file: to make it work with melt (but not XML or via API because melt interprets name=value as a MLT property if there is no colon before equals).
  • Added support for hwaccel_device query string parameter to the avformat producer. This is only used with vaapi (device path) and cuda, d3d11va, or dxva (number).
  • Improved the usage of image slice threading in frei0r. This only applies when threads=0 and only works with some frei0r plugins that you must decide yourself.
  • Added an ellipse item to kdenlivetitle producer.
  • Added support for PNG and GIF as album art in the avformat producer.
  • Added BT.2020 color space metadata to the avformat producer.
  • Resolved many FFmpeg deprecations in the avformat producer making it possible to support AV1 decoding.
  • Added a strobe fitler that periodically makes the alpha channel transparent.
  • Added a new typewriter text filter (currently only works with the kdenlivetitle producer).
  • Improved sound quality for lower pitch shifts in rbpitch.
  • Fixed speed of trick play in the jack, rtaudio, sdl_audio, and sdl2_audio consumers.
  • Fixed matrix for independent channels in swresample filter.
  • Fixed leading zeros for the timer filter.
  • Fixed flickering using affine with a luma transition.
  • Fixed a crash using RGBA images in the qimage producer (regression in v6.22.0).
  • Fixed brightness filter misbehaves on alpha > 1.
  • Fixed writing flac format file does not set its duration in the avformat consumer.
  • Fixed an infinite loop in rbpitch filter.
  • Fixed ttl in the qimage producer.
  • Fixed building with OpenCV 4.5
  • Fixed artifacts with multiple HTML qtext filters and frame threading.
  • Deprecated the start and end properties on the following (use property animation instead):
    • brightness
    • panner
    • boxblur
    • wave
    • volume
  • Deprecated the following services:
    • data_show
    • region
    • transition filter
    • autotrack_rectangle
    • motion_est
    • slowmotion


  • CMake:
    • Fixed building without SWIG.
    • Added many “MOD_…” options to explictly disable modules.
    • Added src/tests and the option BUILD_TESTING, which defaults off.
    • All dependency checks moved to top level CMakeLists.txt.
    • Install melt man page.
    • Install oldfilm SVG files.
    • Added src/examples.
    • Install framework/metaschema.yaml.
    • Fixed plusgpl datadir.
    • Added all swwig/ languages.
    • Increased C++ standard to C++14.
  • Added an AV1 encoding preset.
  • Improved documentation of the requirement for C11.
  • The minimum version of FFmpeg is v4.0 and Libav is no longer supported.



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