[FFmpeg-devel] [PATCH 3/4] doc/filters: add tonemap_opencl document.

Gyan gyandoshi at gmail.com
Tue Oct 30 08:31:47 EET 2018


On Mon, Oct 29, 2018 at 11:29 AM Ruiling Song <ruiling.song at intel.com>
wrote:

> Signed-off-by: Ruiling Song <ruiling.song at intel.com>
> ---
>  doc/filters.texi | 96
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 96 insertions(+)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 83df460..f884ba4 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -16387,6 +16387,7 @@ tmix=frames=3:weights="-1 2 -1":scale=1
>  @end example
>  @end itemize
>
> + at anchor{tonemap}
>  @section tonemap
>  Tone map colors from different dynamic ranges.
>
> @@ -18440,6 +18441,101 @@ Apply sobel operator with scale set to 2 and
> delta set to 10
>  @end example
>  @end itemize
>
> + at section tonemap_opencl
> +
> +Perform HDR(PQ/HLG) to SDR conversion with tone-mapping.
> +
> +It accepts the following parameters:
> +
> + at table @option
> + at item tonemap
> +Specify the tone-mapping operator to be used. Same as tonemap option in
> @ref{tonemap}.
> +
> + at item param
> +Tune the tone mapping algorithm. same as param option in @ref{tonemap}.
> +
> + at item desat
> +Apply desaturation for highlights that exceed this level of brightness.
> The
> +higher the parameter, the more color information will be preserved. This
> +setting helps prevent unnaturally blown-out colors for super-highlights,
> by
> +(smoothly) turning into white instead. This makes images feel more
> natural,
> +at the cost of reducing information about out-of-range colors.
> +
> +The default value is 0.5, and the algorithm here is a little different
> from
> +the cpu version tonemap currently. A setting of 0.0 disables this option.
> +
> + at item threshold
> +The tonemapping algorithm parameters is fine-tuned per each scene. And a
> threshold
> +is used to detect whether the scene has changed or not. If the distance
> beween
> +the current frame average brightness and the current running average
> exceeds
> +a threshold value, we would re-calculate scene average and peak
> brightness.
> +The default value is 0.2.
> +
> + at item format
> +Specify the output pixel format.
> +
> +Currently supported formats are:
> + at table @var
> + at item p010
> + at item nv12
> + at end table
> +
> + at item range, r
> +Set the output color range.
> +
> +Possible values are:
> + at table @var
> + at item tv/mpeg
> + at item pc/jpeg
> + at end table
> +
> +Default is same as input.
> +
> + at item primaries, p
> +Set the output color primaries.
> +
> +Possible values are:
> + at table @var
> + at item bt709
> + at item bt2020
> + at end table
> +
> +Default is same as input.
> +
> + at item transfer, t
> +Set the output transfer characteristics.
> +
> +Possible values are:
> + at table @var
> + at item bt709
> + at item bt2020
> + at end table
> +
> +Default is bt709.
> +
> + at item matrix, m
> +Set the output colorspace matrix.
> +
> +Possible value are:
> + at table @var
> + at item bt709
> + at item bt2020
> + at end table
> +
> +Default is same as input.
> +
> + at end table
> +
> + at subsection Example
> +
> + at itemize
> + at item
> +Convert HDR(PQ/HLG) video to bt2020-transfer-characteristic p010 format
> using linear operator.
> + at example
> +-i INPUT -vf
> "format=p010,hwupload,tonemap_opencl=t=bt2020:tonemap=linear:format=p010,hwdownload,format=p010"
> OUTPUT
> + at end example
> + at end itemize
> +
>  @section unsharp_opencl
>

LGTM.

Gyan


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