[FFmpeg-devel] [PATCH v3] doc/filters: add 4x4 layout example for xstack filter

[Gyan]

On 24-09-2019 06:20 PM, lance.lmwang at gmail.com wrote:
> From: Limin Wang <lance.lmwang at gmail.com>
>
> Reviewed-by: Gyan <ffmpeg at gyani.pro>
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
>   doc/filters.texi | 34 +++++++++++++++++++++++++++++++++-
>   1 file changed, 33 insertions(+), 1 deletion(-)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index e41384aed8..9e76af36a3 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -19057,6 +19057,11 @@ terminates. Default value is 0.
>   @itemize
>   @item
>   Display 4 inputs into 2x2 grid.
> +
> +Below is the 4 inputs position:
> +input1(0, 0)    | input3(w0, 0)
> +input2(0, h0)   | input4(w0, h0)
> +
>   Note that if inputs are of different sizes unused gaps might appear,
>   as not all of output video is used.
>   @example
> @@ -19065,6 +19070,10 @@ xstack=inputs=4:layout=0_0|0_h0|w0_0|w0_h0
>   
>   @item
>   Display 4 inputs into 1x4 grid.
> +
> +Below is the 4 inputs position:
> +input1(0, 0) | input2(0, h0) | input3(0, h0+h1) | input4(0, h0+h1+h2)
> +
>   Note that if inputs are of different sizes unused gaps might appear,
>   as not all of output video is used.
>   @example
> @@ -19073,11 +19082,34 @@ xstack=inputs=4:layout=0_0|0_h0|0_h0+h1|0_h0+h1+h2
>   
>   @item
>   Display 9 inputs into 3x3 grid.
> +
> +Below is the 9 inputs position:
> +input1(0, 0)          |  input4(w0, 0)        | input7(w0+w1, 0)
> +input2(0, h0)         |  input5(w0, h0)       | input8(w0+w1, h0)
> +input3(0, h0+h1)      |  input6(w0, h0+h1)    | input9(w0+w1, h0+h1)
> +
>   Note that if inputs are of different sizes unused gaps might appear,
>   as not all of output video is used.
>   @example
> -xstack=inputs=9:layout=w3_0|w3_h0+h2|w3_h0|0_h4|0_0|w3+w1_0|0_h1+h2|w3+w1_h0|w3+w1_h1+h2
> +xstack=inputs=9:layout=0_0|0_h0|0_h0+h1|w0_0|w0_h0|w0_h0+h1|w0+w1_0|w0+w1_h0|w0+w1_h0+h1
>   @end example
> +
> + at item
> +Display 16 inputs into 4x4 grid.
> +
> +Below is the 16 inputs position:
> +input1(0, 0)        |  input5(w0, 0)        | input9 (w0+w1, 0)        | input13(w0+w1+w2, 0)
> +input2(0, h0)       |  input6(w0, h0)       | input10(w0+w1, h0)       | input14(w0+w1+w2, h0)
> +input3(0, h0+h1)    |  input7(w0, h0+h1)    | input11(w0+w1, h0+h1)    | input15(w0+w1+w2, h0+h1)
> +input4(0, h0+h1+h2) |  input8(w0, h0+h1+h2) | input12(w0+w1, h0+h1+h2) | input16(w0+w1+w2, h0+h1+h2)
> +
> +Note that if inputs are of different sizes unused gaps might appear,
> +as not all of output video is used.
> + at example
> +xstack=inputs=16:layout=0_0|0_h0|0_h0+h1|0_h0+h1+h2|w0_0|w0_h0|w0_h0+h1|w0_h0+h1+h2|w0+w1_0|\
> +w0+w1_h0|w0+w1_h0+h1|w0+w1_h0+h1+h2|w0+w1+w2_0|w0+w1+w2_h0|w0+w1+w2_h0+h1|w0+w1+w2_h0+h1+h2
> + at end example
> +
>   @end itemize
>   
>   @anchor{yadif}

I tested the HTML and manual output and linebreaks aren't honoured. Even 
with manual linebreaks, the grid isn't aligned. You should manually set 
and test it.

Gyan