[MPlayer-DOCS] Improved vi_qfactor and (tcplx|scplx|p)_mask

[Diego Biurrun]

Guillaume POIRIER writes:
> Thanks to Loren Merritt, here are some better descriptions for
> remaining, poorly documented masking options.

All hail Loren Merritt :-)

> It also features vi_qfactor's description, as it was lacking.

Good.

>  .B tcplx_mask=<0.0\-1.0>
>  temporal complexity masking (default: 0.0 (disabled))
> +Imagine a scene with a bird flying across the whole scene, tcplx_mask
> +will decrease the bird's macroblocks quantizers (thus decreasing their

macroblock

> +quality) as the human eye usually doesn't have time to see all the bird's
> +details.
> +Be warned that if the masked object stops (e.g.\& the bird lands) it is
> +likely to look horrible for a a short period of time (until the encoder
> +figures out that the object isn't moving and needs refined blocks).
> +The saved bits will be spent on other parts of the video, which may increase
> +subjective quality, provided that tcplx_mask is carefully chosen.

Avoid short forms.

> +Imagine a scene with grass (which usually has a great spatial complexity),
> +a blue sky and a house, scplx_mask will raise grass' macroblocks quantizers

raise the macroblock of the grass

> +.I NOTE:
> +This setting doesn't have the same effect as using a custom matrix that

Avoid short forms.

> +whould compress harder high frequencies, as scplx_mask will reduce the

high frequencies harder

> +quality of P-blocks even if only DC is changing, which will probably not

P-blocks or P-frames?


> +.B p_mask=<0.0\-1.0> (also see vi_qfactor)
> +Reduces the quality of inter blocks, which is equivalent to increasing
> +the quality of intra blocks, since the same average bitrate will be
> +distributed by the rate controler to the whole video sequence

controller

> +(default: 0.0 (disabled)).
> +p_mask=1.0 doubles the bits allocated to each intra block.

Same question here as in the paragraph above: Are we talking about
blocks or frames?

Commit with the suggested fixes.

Diego