ffmpeg noise filter usage based on mplayer noise settings?

[Selur]

Since ffmpegs noise filter is ported from mplayers noise filter.
I was wondering if someone here can tell me how to convert some mplayer noise calls to ffmpeg?

mplayers option to add noise:

noise[=luma[u][t|a][h][p]:chroma[u][t|a][h][p]]
  Adds noise.
     <0-100>
          luma noise
     <0-100>
          chroma noise
     u    uniform noise (gaussian otherwise)
     t    temporal noise (noise pattern changes between frames)
     a    averaged temporal noise (smoother, but a lot slower)
     h    high quality (slightly better looking, slightly slower)
     p    mix random noise with a (semi)regular pattern

So for mplayer I can in example use:
- 'noise=5t' to add temporal luma noise with a strength of 5
- 'noise=5t:5t' to add temporal luma&chroma noise with a strength of 5
- 'noise=11p:30u' to add random luma noise with a strength of 11 and uniform chroma noise with a strength of 30
- 'noise=9thp:5utahp' to add temporal high quality random luma noise with a strength of 9 and uniform averaged high quality random chroma noise

How I understood it, for both (mplayer and ffmpeg):
The strength sets amount of noise added to pixel and amount of pixels that have noise added.
Thus 0 for strength should return unmodified video.

Problem is: I don't quite get how to map this to ffmpeg.

ffmpegs option to add noise:

Add noise on video input frame.

The filter accepts the following options:

all_seed
c0_seed
c1_seed
c2_seed
c3_seed
Set noise seed for specific pixel component or all pixel components in case of all_seed. Default value is 123457.

all_strength, alls
c0_strength, c0s
c1_strength, c1s
c2_strength, c2s
c3_strength, c3s
Set noise strength for specific pixel component or all pixel components in case all_strength. Default value is 0. Allowed range is [0, 100].

all_flags, allf
c0_flags, c0f
c1_flags, c1f
c2_flags, c2f
c3_flags, c3f
Set pixel component flags or set flags for all components if all_flags. Available values for component flags are:

    ‘a’
        averaged temporal noise (smoother) 
    ‘p’
        mix random noise with a (semi)regular pattern 
    ‘t’
        temporal noise (noise pattern changes between frames) 
    ‘u’
        uniform noise (gaussian otherwise)

atm. I would guess that
- mplayer "noise=5t:5t", would map to ffmpeg "noise=alls=5:allf=t"
but I don't quite get how the luma&chroma differentiation and different strength can be translated into the ffmpeg syntax.


-> Does someone know how to do this?

Cu Selur

[pandy]

Since ffmpegs noise filter is ported from mplayers noise filter.
I was wondering if someone here can tell me how to convert some mplayer noise calls to ffmpeg?

mplayers option to add noise:

noise[=luma[u][t|a][h][p]:chroma[u][t|a][h][p]]
  Adds noise.
     <0-100>
          luma noise
     <0-100>
          chroma noise
     u    uniform noise (gaussian otherwise)
     t    temporal noise (noise pattern changes between frames)
     a    averaged temporal noise (smoother, but a lot slower)
     h    high quality (slightly better looking, slightly slower)
     p    mix random noise with a (semi)regular pattern

So for mplayer I can in example use:
- 'noise=5t' to add temporal luma noise with a strength of 5
- 'noise=5t:5t' to add temporal luma&chroma noise with a strength of 5
- 'noise=11p:30u' to add random luma noise with a strength of 11 and uniform chroma noise with a strength of 30
- 'noise=9thp:5utahp' to add temporal high quality random luma noise with a strength of 9 and uniform averaged high quality random chroma noise

How I understood it, for both (mplayer and ffmpeg):
The strength sets amount of noise added to pixel and amount of pixels that have noise added.
Thus 0 for strength should return unmodified video.

Problem is: I don't quite get how to map this to ffmpeg.

ffmpegs option to add noise:

Add noise on video input frame.

The filter accepts the following options:

all_seed
c0_seed
c1_seed
c2_seed
c3_seed
Set noise seed for specific pixel component or all pixel components in case of all_seed. Default value is 123457.

all_strength, alls
c0_strength, c0s
c1_strength, c1s
c2_strength, c2s
c3_strength, c3s
Set noise strength for specific pixel component or all pixel components in case all_strength. Default value is 0. Allowed range is [0, 100].

all_flags, allf
c0_flags, c0f
c1_flags, c1f
c2_flags, c2f
c3_flags, c3f
Set pixel component flags or set flags for all components if all_flags. Available values for component flags are:

    ‘a’
        averaged temporal noise (smoother) 
    ‘p’
        mix random noise with a (semi)regular pattern 
    ‘t’
        temporal noise (noise pattern changes between frames) 
    ‘u’
        uniform noise (gaussian otherwise)

atm. I would guess that
- mplayer "noise=5t:5t", would map to ffmpeg "noise=alls=5:allf=t"
but I don't quite get how the luma&chroma differentiation and different strength can be translated into the ffmpeg syntax.


-> Does someone know how to do this?

Cu Selur

noise=alls=5:allf=t works for all planes - set separate planes (channels) assuming that Y is firsts channel, Cb and Cr next second and third.

noise=c0s=5:c0f=t:c1s=5:c1f=t:c2s=5:c2f=t

[Selur]

Okay, that is what I first thought too:

all... = all channels

c0 = Y = luma channel
c1+c2 = chroma channel
c1 = Cb
c2 = Cr
but what about c3 ?

[pandy]

Okay, that is what I first thought too:

all... = all channels

c0 = Y = luma channel
c1+c2 = chroma channel
c1 = Cb
c2 = Cr
but what about c3 ?

alpha
generalized way is 3 channels for video + additional channel for alpha (transparency) (it works for every known to me component video representation)

[Selur]

Doh,... alpha,... totally forgot about alpha

Thanks!

[pandy]

Doh,... alpha,... totally forgot about alpha

Thanks!

NP, glad to help, even if on ffmpeg: "I am only an egg"*

Stranger in a Strange Land, author Robert A. Heinlein.