[Radium[_4_]]

Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...ormalimage.jpg

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.lopass.jpg

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of the
signal to be down-shifted until the highest frequency is low-enough to
be acceptable to the device. This down-shifting should be done w/out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.


Thanks for your assistance, cooperation, and understanding,

Radium

[BobG]

If you play the tape or record faster, the pitch shifts up. If colors
are analogous to pitch, speeding up would be a shift to the blue,
slowing down would be a red shift.

[Jerry Avins]

Radium wrote:
Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

A video signal consists of a succession of still images that follow one
another at fixed intervals. What you call tempo is determined by how
different each image id from the ones before and after it. That makes
what you write next wrong.

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Sharpness is altered by applying a filter. There are sharpening and
softening filters.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...ormalimage.jpg

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.lopass.jpg

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of the
signal to be down-shifted until the highest frequency is low-enough to
be acceptable to the device. This down-shifting should be done w/out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.

But it together and be more specific.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Radium[_4_]]

On Aug 21, 4:39 pm, Jerry Avins wrote:

A video signal consists of a succession of still images that follow one
another at fixed intervals. What you call tempo is determined by how
different each image id from the ones before and after it. That makes
what you write next wrong.

Okay. How would you correct it?

[AnthonyR.]

"Radium" wrote in message
oups.com...
Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...ormalimage.jpg

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.lopass.jpg

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of the
signal to be down-shifted until the highest frequency is low-enough to
be acceptable to the device. This down-shifting should be done w/out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.


Thanks for your assistance, cooperation, and understanding,

Radium


So basically you want software that analyzes each frame the way mpeg coverts
video and instead of eliminating file size by compressing the images, you
want to have it eliminate most of the static images and thus reduce file
duration instead. Is this correct?
So if a scene has movement and talking you want that left alone but if the
person is just standing still or not much action going on in the scene have
it eliminated and blended so it shortens the duration but not affecting the
movement speed thus making the scene shorter in length.
I don't know of anything that would do this to video but I could see a use
for it.
DVD player software can speed up movement by say 10% and allow the sound to
not be effected as far a pitch goes, this is useful for watching say a 2
hour and 15 minute movie on a flight that is 2 hours long.
Is this what you are trying to find?

AnthonyR.

[Jerry Avins]

Radium wrote:
On Aug 21, 4:39 pm, Jerry Avins wrote:

A video signal consists of a succession of still images that follow one
another at fixed intervals. What you call tempo is determined by how
different each image id from the ones before and after it. That makes
what you write next wrong.

Okay. How would you correct it?
I would leave out the rest of the paragraph. It's based on a false
assumption.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Stuart]

"BobG" wrote in message
oups.com...
If you play the tape or record faster, the pitch shifts up. If colors
are analogous to pitch, speeding up would be a shift to the blue,
slowing down would be a red shift.


Sound is physical - Light is electromagnetic radiation

That would make a great Sci-Fi effect to depict 'beings' in a different
temporal dimension co-existing with us but what you describe is the effect
of motion linking the audio analogy to video which is not valid. Sound is an
air-pressure wave whose speed changes depending on the medium whereas light
is part of the electromagnetic spectrum whose speed is fixed to the speed of
light and except for some very high-end academic experiments never changes.
Never-the-less it's a good special effects used in a modified way in the BBC
production Ultra Violet.

[glen herrmannsfeldt]

Radium wrote:

(snip)

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-

It would be reasonably similar to a cyclical intensity of a lamp,
or something similar. A moving object is different.

pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

-- glen

[Jerry Avins]

Stuart wrote:
"BobG" wrote in message
oups.com...
If you play the tape or record faster, the pitch shifts up. If colors
are analogous to pitch, speeding up would be a shift to the blue,
slowing down would be a red shift.


Sound is physical - Light is electromagnetic radiation

That would make a great Sci-Fi effect to depict 'beings' in a different
temporal dimension co-existing with us but what you describe is the effect
of motion linking the audio analogy to video which is not valid. Sound is an
air-pressure wave whose speed changes depending on the medium whereas light
is part of the electromagnetic spectrum whose speed is fixed to the speed of
light and except for some very high-end academic experiments never changes.
Never-the-less it's a good special effects used in a modified way in the BBC
production Ultra Violet.

You have very little influence on the speed of sound in the medium in
which you live.

The speed of light depends on the medium it travels through and
sometimes on the frequency. Consider a prism's dispersion.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Radium[_4_]]

On Aug 21, 5:19 pm, "AnthonyR." wrote:

So basically you want software that analyzes each frame the way mpeg coverts
video and instead of eliminating file size by compressing the images, you
want to have it eliminate most of the static images and thus reduce file
duration instead. Is this correct?

I don't think so. Any thing in the video with a temporal/spatial
frequency component that is too high for a low-bandwidth device to
accept, should have all of its frequencies downshifted until the
highest frequency is low-enough for the low-bandwidth device to accept
without any aliasing or other artifacts associated with a frequency
exceeding the limits.

So if a scene has movement and talking you want that left alone but if the
person is just standing still or not much action going on in the scene have
it eliminated and blended so it shortens the duration but not affecting the
movement speed thus making the scene shorter in length.

No. The length of any parts of the movie should not be affected at
all.

DVD player software can speed up movement by say 10% and allow the sound to
not be effected as far a pitch goes, this is useful for watching say a 2
hour and 15 minute movie on a flight that is 2 hours long.
Is this what you are trying to find?

Not really. This change in video-frequency has nothing to do with
speeding up a video. The movie should remain exactly the same length.
Two hours should stay two hours.

[Stuart]

"BobG" wrote in message
oups.com...
If you play the tape or record faster, the pitch shifts up. If colors
are analogous to pitch, speeding up would be a shift to the blue,
slowing down would be a red shift.



This is only true in the domestic experience using a gramophone record or
tape but in the world of TV, Film and Music Industries if a producer asks
me to speed up some dialog I will do so without affecting the pitch,
likewise I can take the pitch up without affecting the tempo. The chipmunk
sound is of course achieved by both increasing tempo and pitch. In the
analog domain this has been possible and widely used to tighten up
commercials etc since 1958 via the EMT Pitch and Tempo Regulator ( a German
invention of 8 playback heads in a rotating drum either in the direction or
in counter rotation to the linear motion of the tape) and in the modern
digital domain with a simple plug-in for programs like Adobe Audition or
Wavelab.

[Jerry Avins]

Radium wrote:
On Aug 21, 5:19 pm, "AnthonyR." wrote:

So basically you want software that analyzes each frame the way mpeg coverts
video and instead of eliminating file size by compressing the images, you
want to have it eliminate most of the static images and thus reduce file
duration instead. Is this correct?

I don't think so. Any thing in the video with a temporal/spatial
frequency component that is too high for a low-bandwidth device to
accept, should have all of its frequencies downshifted until the
highest frequency is low-enough for the low-bandwidth device to accept
without any aliasing or other artifacts associated with a frequency
exceeding the limits.

Visible light extends for less than one octave, nominally from 400 to
700 nanometers. Those are wavelengths more or less centered around
500,000,000,000,000 Hz. You can't shift the band much and still see it.

So if a scene has movement and talking you want that left alone but if the
person is just standing still or not much action going on in the scene have
it eliminated and blended so it shortens the duration but not affecting the
movement speed thus making the scene shorter in length.

No. The length of any parts of the movie should not be affected at
all.

DVD player software can speed up movement by say 10% and allow the sound to
not be effected as far a pitch goes, this is useful for watching say a 2
hour and 15 minute movie on a flight that is 2 hours long.
Is this what you are trying to find?

Not really. This change in video-frequency has nothing to do with
speeding up a video. The movie should remain exactly the same length.
Two hours should stay two hours.

Describe the action of a person taking a one-mile walk and some stations
along the way.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Radium[_4_]]

On Aug 21, 9:19 pm, Jerry Avins wrote:

Radium wrote:

I don't think so. Any thing in the video with a temporal/spatial
frequency component that is too high for a low-bandwidth device to
accept, should have all of its frequencies downshifted until the
highest frequency is low-enough for the low-bandwidth device to accept
without any aliasing or other artifacts associated with a frequency
exceeding the limits.

Visible light extends for less than one octave, nominally from 400 to
700 nanometers. Those are wavelengths more or less centered around
500,000,000,000,000 Hz. You can't shift the band much and still see it.

You're talking about color-frequency. Totally irrelevant to my
discussion of video-frequency. I am talking about temporal and spatial
frequency, not color-frequency.

Color-frequencies = frequencies of electromagnetic radiation visible
to the human eye, which as you pointed out, corresponds to wavelengths
that are at least 400 nm but no more than 700 nm.

Once again, by "video frequency", I am referring to the temporal and
spatial frequencies of the video signal, not the color-frequencies.

Not really. This change in video-frequency has nothing to do with
speeding up a video. The movie should remain exactly the same length.
Two hours should stay two hours.

Describe the action of a person taking a one-mile walk and some stations
along the way.

Huh?

[isw]

In article .com,
Radium wrote:

Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.normalimag
e.jpg

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.lopass.jpg

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of the
signal to be down-shifted until the highest frequency is low-enough to
be acceptable to the device. This down-shifting should be done w/out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.

I didn't want to post this on the original thread because it would have
been lost in the noise.

There is a very fundamental difference between a data stream
representing audio, and one representing video. Analog or digital; makes
no difference.

A stream representing audio is a continuous stream of information, with
every part of it temporally related to a specific time in the audio. It
can be slowed down, sped up, or have pieces cut out or added at will.
These last are the basis for the "speed up/slow down without changing
the pitch" algorithms.

There is absolutely no parallel to this for video, as it is handled
today. Unlike audio, video is a series of still images, equally spaced
(hopefully) in time -- i.o.w. it is always temporally quantized.

It is possible to change the spatial resolution (temporal spacing
between successive images) and the spatial resolution (within each
individual image) totally independently, and in fact, the two need to
bear no particular relation each to the other. You can create high
temporal resolution but low spatial resolution -- or the other way
around -- easily. You can also increase or reduce the temporal
resolution by interpolation/decimation while leaving the spatial
resolution totally unaffected, and you can also do the "reverse".

The fact that there is essentially no relation between these two
entities -- i.e. the data stream is comprised of a sequence of
descriptions of a series of still images -- is the reason why what you
want to do is almost certainly impossible.

If you really want to try, the first step will be to devise a method of
recording video that does not quantize the temporal axis; i.e. not using
a sequence of still images.

Good luck, and great fame awaits.

Isaac

[[email protected]]

On Aug 21, 4:13 pm, Radium wrote:
Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of
an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two
[temporal
and spatial].

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/
low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-
changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will
not
cause your speech to slow down.

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...4/sab/report.n...

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...4/sab/report.l...

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-
frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of
the
signal to be down-shifted until the highest frequency is low-enough
to
be acceptable to the device. This down-shifting should be done w/
out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.

Thanks for your assistance, cooperation, and understanding,

Radium

I can't believe I'm jumping into this muck. Totally useless point in
that any changes in frequency leaves you with a signal you can't use.
No recorder can record it and no monitor can display it. Now if
you're willing to live within the frame/line rate definitions, then
changing frequencies _within the line frame boundaries_ would be
similar to a DVE zoom but there is much more capability than that. 25
years agon the Ampex ADO and Quantel Mirage were literally twisting
pictures into screws, making them into spheres, rolling them up. Tape
machines have been slo-mo and speeding up for over 30 years. Stuff is
way cooler now. Go look it up.

GG

[BOING!!]

"Radium" wrote in message
oups.com...
Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

[

Oh dear how busy you are, making up nonsense trolls! If you were serious,
you would give a couple links to youtube showing examples of spatial &
temportal "pitch shifting" video equivs

[Richard Dobson]

Radium wrote:
...

Describe the action of a person taking a one-mile walk and some stations
along the way.


Huh?


Wide-screen TV showing whole soccer pitch. Man in middle distance runs
from left goal to right goal. Takes 100 paces, 20 seconds. You want to
slow this down to (say) 10 paces (pedestrian equivalent to
wing-flapping). With no artifacts. Does he still reach the other goal,
in 20 seconds? Does it not look like someone running on the moon?

Richard Dobson

[VelociChicken]

"Radium" wrote in message
oups.com...
Hi:

I started a new thread because the previous one started to go into
tangent of digital vs. analog but was filled with emotions and
personal vendettas rather than science and logic. So I changed the
thread.

Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

Mainly I don't really believe this whole question, BUT the only thing I can
think of that comes close is:

Take frames 1 to 4 of someone running for example, replace frames 2 & 3 with
a 'tween' of 1 & 4 - and so on through 4-8 etc.
That way you keep your sharpness (tween is not motion blur) yet loose half
your detail of movement. And would look very strange indeed. Probs need to
do all manner of vid tricks to tween certain films of course.

Cheers,

Dave H

[Jerry Avins]

Radium wrote:
On Aug 21, 9:19 pm, Jerry Avins wrote:

Radium wrote:

I don't think so. Any thing in the video with a temporal/spatial
frequency component that is too high for a low-bandwidth device to
accept, should have all of its frequencies downshifted until the
highest frequency is low-enough for the low-bandwidth device to accept
without any aliasing or other artifacts associated with a frequency
exceeding the limits.

Visible light extends for less than one octave, nominally from 400 to
700 nanometers. Those are wavelengths more or less centered around
500,000,000,000,000 Hz. You can't shift the band much and still see it.

You're talking about color-frequency. Totally irrelevant to my
discussion of video-frequency. I am talking about temporal and spatial
frequency, not color-frequency.

Describe what you mean by "video frequency". To me, it means how often
the still image that makes up the video is updated. I call it the frame
rate.

Color-frequencies = frequencies of electromagnetic radiation visible
to the human eye, which as you pointed out, corresponds to wavelengths
that are at least 400 nm but no more than 700 nm.

Once again, by "video frequency", I am referring to the temporal and
spatial frequencies of the video signal, not the color-frequencies.

Video consists of a sequence of still pictures. There are no temporal
frequencies. Spatial frequency relates to resolution.

Not really. This change in video-frequency has nothing to do with
speeding up a video. The movie should remain exactly the same length.
Two hours should stay two hours.

Describe the action of a person taking a one-mile walk and some stations
along the way.

Huh?

The video is of a person walking leisurely. She covers a mile in 20
minutes. With your magic, we slow her gait to half speed, but she still
finishes that same mile in the the same 20 minutes. How?

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Jerry Avins]

isw wrote:

...

Good luck, and great fame awaits.

Isaac,

If Radium doesn't take the trouble to understand your clear exposition,
he's beyond help.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Ron Capik]

Jerry Avins wrote:

....snip..

If Radium doesn't take the trouble to understand your clear exposition,
he's beyond help.

Jerry
--

You sound like someone who has never followed a
"Radium" thread before. ;-}

[The extent of the cross-post lists says much about
his usenet ~mastery~ ]

Later...

Ron
--

[Rich Grise]

On Wed, 22 Aug 2007 01:17:31 +0000, Stuart wrote:
"BobG" wrote in message
oups.com...
If you play the tape or record faster, the pitch shifts up. If colors
are analogous to pitch, speeding up would be a shift to the blue,
slowing down would be a red shift.

Sound is physical - Light is electromagnetic radiation

That would make a great Sci-Fi effect to depict 'beings' in a different
temporal dimension co-existing with us but what you describe is the effect
of motion linking the audio analogy to video which is not valid. Sound is an
air-pressure wave whose speed changes depending on the medium whereas light
is part of the electromagnetic spectrum whose speed is fixed to the speed of
light and except for some very high-end academic experiments never changes.
Never-the-less it's a good special effects used in a modified way in the BBC
production Ultra Violet.

I believe the point was about the Doppler effect, which they both
experience, albeit in very different media. In fact, you can see this
in water waves, if you have a boat that's going more slowly than the
"speed of wave" in that body of water.

But, yes, alas, other than moving at a significant fraction of c, I
don't think there's any way to exploit blue-shift. ;-)

Hope This Helps!
Rich

[Ron N.]

On Aug 21, 4:13 pm, Radium wrote:
Anyways, Adobe Audition and voice-changers allow the frequencies of an
audio signal to be shifted w/out low-pass filtering or changing the
tempo. There are two video-equivalents of this because, while audio
has only one frequency component [temporal], video has two [temporal
and spatial].

Voice-changing and pitch shifting algorithms work
by duplicating or throwing away information which
the ear can rarely detect, but would be really
obvious to the eye (a phoneme may sound the same
with less or more excitation cycles, but a picture
of your family would not look the same with a some
people missing, or with twin children added.)

MPEG-2 video compression already does a coarse
equivalent of time-domain pitch shifting via motion
estimation and compensation, e.g. it throws away
whole frames of video and repeats the spacial
components from previous frames, sometimes skipping
some new motion (leading to jerky patches of video
playback if the compression rate is lower than a
suitable information bandwidth).


IMHO. YMMV.

[Jim Kelley]

Radium wrote:

The temporal video-equivalent would be changing the rate of back/
forth, up-down or other repetitive/cyclical movement [such as wing-
flapping or flickering of lights] of the video signal without high/low-
pass-filtering, separating any portion of the video signal, or
changing the speed at which the video-signal -- just as voice-changers
can lower the frequency of audio without changing the speed of the
audio. Using a voice-changer to decrease the pitch your voice will not
cause your speech to slow down.

In order to change the 'spacial frequency' aspect of video data
without altering the 'temporal' aspect you have to either add or
delete information interstitially and then play back the altered data
at a compensated data rate. (Using the term 'data' in the most
general sense here.)

jk

The spatial video-equivalent would be changing the "sharpness" of a
still image without high/low-pass-filtering or changing the size of
the image.

Below is an example of low-pass-filtering in the spatial domain:

Here is an original pictu

http://www-dse.doc.ic.ac.uk/~nd/surp...ormalimage.jpg

Here is the picture after low-pass filtering:

http://www-dse.doc.ic.ac.uk/~nd/surp...ort.lopass.jpg

I obviously do not want this at all. Low-pass filtering involves
removing high-frequency components while preserving the low-frequency
components. Once again, this is not what I want. If a device cannot
handle high-frequencies, then I would like all the frequencies of the
signal to be down-shifted until the highest frequency is low-enough to
be acceptable to the device. This down-shifting should be done w/out
slowing the speed of the signal -- or in the case of spatial
frequency, w/out increasing the size of the image.


Thanks for your assistance, cooperation, and understanding,

Radium

[isw]

In article om,
"Ron N." wrote:

MPEG-2 video compression already does a coarse
equivalent of time-domain pitch shifting via motion
estimation and compensation, e.g. it throws away
whole frames of video and repeats the spacial
components from previous frames, sometimes skipping
some new motion (leading to jerky patches of video
playback if the compression rate is lower than a
suitable information bandwidth).

Not really. MPEG-2 is frame rate conservative, end-to-end. In fact, the
output frame rate is required by the standard to be *identical* to the
input rate. That has to be the case for it to be able to handle NTSC or
PAL delivered to ordinary TV sets.

And if there are "jerky patches", that just means that it was improperly
applied.

Isaac

[Ron N.]

On Aug 22, 8:31 pm, isw wrote:
In article om,
"Ron N." wrote:

MPEG-2 video compression already does a coarse
equivalent of time-domain pitch shifting via motion
estimation and compensation, e.g. it throws away
whole frames of video and repeats the spatial
components from previous frames, sometimes skipping
some new motion (leading to jerky patches of video
playback if the compression rate is lower than a
suitable information bandwidth).

Not really. MPEG-2 is frame rate conservative, end-to-end. In fact, the
output frame rate is required by the standard to be *identical* to the
input rate. That has to be the case for it to be able to handle NTSC or
PAL delivered to ordinary TV sets.

MPEG is frame rate conservative, but only the I frames are
actually sent as full images. The P and B frames are made
up out of some duplicated and possibly displaced contents of
other frames, plus some quantized portion of an error vector
depending on the compression rate. Thus the data bandwidth
required for an P and B frames is a fraction of that typically
required for the full image, as contained a nearby I frame.

Some pitch-shifters or time-stretchers also duplicate and
blend preceding and following periods of waveforms or
spectral frame contents.

[isw]

In article . com,
"Ron N." wrote:

On Aug 22, 8:31 pm, isw wrote:
In article om,
"Ron N." wrote:

MPEG-2 video compression already does a coarse
equivalent of time-domain pitch shifting via motion
estimation and compensation, e.g. it throws away
whole frames of video and repeats the spatial
components from previous frames, sometimes skipping
some new motion (leading to jerky patches of video
playback if the compression rate is lower than a
suitable information bandwidth).

Not really. MPEG-2 is frame rate conservative, end-to-end. In fact, the
output frame rate is required by the standard to be *identical* to the
input rate. That has to be the case for it to be able to handle NTSC or
PAL delivered to ordinary TV sets.

MPEG is frame rate conservative, but only the I frames are
actually sent as full images. The P and B frames are made
up out of some duplicated and possibly displaced contents of
other frames, plus some quantized portion of an error vector
depending on the compression rate. Thus the data bandwidth
required for an P and B frames is a fraction of that typically
required for the full image, as contained a nearby I frame.

Yup. Also, some of those frames are sent out of sequence (I or P
"anchor" frames must be present first, in order for the interpolated
frames to be recreated), but every frame has a representation of some
sort in the stream, every frame gets put in its proper place by the
decoder, and no frames are skipped.

Some pitch-shifters or time-stretchers also duplicate and
blend preceding and following periods of waveforms or
spectral frame contents.

Yes again. The difference is that with MPEG video the "duplicating and
blending" has zero effect on the frame rate (i.e., the temporal
resolution).

There is an interesting sort-of exception to frame rate conservation,
when film source is encoded at 24 FPS (actually about 23.98) and the
decoder performs 3-2 pulldown to deliver the NTSC-required 29.97 FPS,
but that's not germane to this discussion.

Isaac

[Ron N.]

On Aug 23, 10:02 am, isw wrote:
There is an interesting sort-of exception to frame rate conservation,
when film source is encoded at 24 FPS (actually about 23.98) and the
decoder performs 3-2 pulldown to deliver the NTSC-required 29.97 FPS,
but that's not germane to this discussion.

Actually, it is very germane, since 3-2 pulldown is similar
to how some primitive audio pitch/rate changing hardware worked,
by duplicating small time domain frames of audio at a fixed
proportion and rate. Some MPEG decoders do "special effects"
by varying the frame duplicate/drop fractions to slow down
or speed up playback using the same mechanism as for pulldown.

[robert bristow-johnson]

On Aug 23, 3:37 am, "Ron N." wrote:

Some pitch-shifters or time-stretchers also duplicate and
blend preceding and following periods of waveforms or
spectral frame contents.

when i first saw the thread title, that's what i first thought about.
actually, not pitch-shifting but more time-scaling. it seems to me
natural that if they were speeding up or slowing down the motion in
the video (which means only for the termporal dimension, not either
"x" or "y"), that would naturally correspond to the same speeding up
or slowing down of tempo (without pitch change) of the audio. if you
twist the knob that makes the actress talk faster (Ms. Motormouth), it
shouldn't be upshifting her pitch to sound like Wendy or Bebe in South
Park.

r b-j

[robert bristow-johnson]

On Aug 22, 1:37 am, isw wrote:

The fact that there is essentially no relation between these two
entities -- i.e. the data stream is comprised of a sequence of
descriptions of a series of still images -- is the reason why what you
want to do is almost certainly impossible.

If you really want to try, the first step will be to devise a method of
recording video that does not quantize the temporal axis; i.e. not using
a sequence of still images.

can't we think of the intensity (and chroma components) of a
particular point (x,y) of a still image as a sampled (at a rate of 30
Hz) value of a continuous-time signal that represents intensity at
that point? i.e. we have I(x,y,t) being sampled as I(x,y,n*T). and
then use some kinda interpolation to hypothetically reconstruct the
"still" images in between the sequence we are given? i imagine there
would be some blurring, but if the resolution was very good to start
with, would that not work. at least as a beginning point?

r b-j

[Gene E. Bloch]

On 8/23/2007, robert bristow-johnson posted this:
On Aug 22, 1:37 am, isw wrote:

The fact that there is essentially no relation between these two
entities -- i.e. the data stream is comprised of a sequence of
descriptions of a series of still images -- is the reason why what you
want to do is almost certainly impossible.

If you really want to try, the first step will be to devise a method of
recording video that does not quantize the temporal axis; i.e. not using
a sequence of still images.

can't we think of the intensity (and chroma components) of a
particular point (x,y) of a still image as a sampled (at a rate of 30
Hz) value of a continuous-time signal that represents intensity at
that point? i.e. we have I(x,y,t) being sampled as I(x,y,n*T). and
then use some kinda interpolation to hypothetically reconstruct the
"still" images in between the sequence we are given? i imagine there
would be some blurring, but if the resolution was very good to start
with, would that not work. at least as a beginning point?

r b-j

Yes. Radium included that idea in his first thread of the week, but it
was not liked by the community[1] :-)

I thought it was perhaps his only cogent idea, but OTOH, I'm not sure
where to take it.

[1] At least in the part of the thread that I read.

--
Gene E. Bloch (Gino)
letters617blochg3251
(replace the numbers by "at" and "dotcom")

[isw]

In article . com,
robert bristow-johnson wrote:

On Aug 22, 1:37 am, isw wrote:

The fact that there is essentially no relation between these two
entities -- i.e. the data stream is comprised of a sequence of
descriptions of a series of still images -- is the reason why what you
want to do is almost certainly impossible.

If you really want to try, the first step will be to devise a method of
recording video that does not quantize the temporal axis; i.e. not using
a sequence of still images.

can't we think of the intensity (and chroma components) of a
particular point (x,y) of a still image as a sampled (at a rate of 30
Hz) value of a continuous-time signal that represents intensity at
that point? i.e. we have I(x,y,t) being sampled as I(x,y,n*T). and
then use some kinda interpolation to hypothetically reconstruct the
"still" images in between the sequence we are given? i imagine there
would be some blurring, but if the resolution was very good to start
with, would that not work. at least as a beginning point?

That's not far from the way PAL (25 FPS)-to-NTSC (29.97 FPS) converters
work.

Isaac

[Jerry Avins]

Ron N. wrote:
On Aug 23, 10:02 am, isw wrote:
There is an interesting sort-of exception to frame rate conservation,
when film source is encoded at 24 FPS (actually about 23.98) and the
decoder performs 3-2 pulldown to deliver the NTSC-required 29.97 FPS,
but that's not germane to this discussion.

Actually, it is very germane, since 3-2 pulldown is similar
to how some primitive audio pitch/rate changing hardware worked,
by duplicating small time domain frames of audio at a fixed
proportion and rate. Some MPEG decoders do "special effects"
by varying the frame duplicate/drop fractions to slow down
or speed up playback using the same mechanism as for pulldown.

I think he means the change from 2:2 pull-down's natural rate of 30fps
and TV's 29.97. I call that negligible.

jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Jerry Avins]

robert bristow-johnson wrote:
On Aug 23, 3:37 am, "Ron N." wrote:
Some pitch-shifters or time-stretchers also duplicate and
blend preceding and following periods of waveforms or
spectral frame contents.

when i first saw the thread title, that's what i first thought about.
actually, not pitch-shifting but more time-scaling. it seems to me
natural that if they were speeding up or slowing down the motion in
the video (which means only for the termporal dimension, not either
"x" or "y"), that would naturally correspond to the same speeding up
or slowing down of tempo (without pitch change) of the audio. if you
twist the knob that makes the actress talk faster (Ms. Motormouth), it
shouldn't be upshifting her pitch to sound like Wendy or Bebe in South
Park.

But he wants her to talk faster, say the same number of words, and
finish in the same time! What's worse, I think he's serious.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Radium[_4_]]

On Aug 23, 11:31 am, robert bristow-johnson
wrote:

when i first saw the thread title, that's what i first thought about.
actually, not pitch-shifting but more time-scaling.

That's the opposite of what I'm looking for.

it seems to me
natural that if they were speeding up or slowing down the motion in
the video (which means only for the termporal dimension, not either
"x" or "y"), that would naturally correspond to the same speeding up
or slowing down of tempo (without pitch change) of the audio. if you
twist the knob that makes the actress talk faster (Ms. Motormouth), it
shouldn't be upshifting her pitch to sound like Wendy or Bebe in South
Park.

I want the actress to talk at the same speed, at a lower-pitch, and
finish at the same-time without any low-pass filtering.

[isw]

In article ,
Jerry Avins wrote:

Ron N. wrote:
On Aug 23, 10:02 am, isw wrote:
There is an interesting sort-of exception to frame rate conservation,
when film source is encoded at 24 FPS (actually about 23.98) and the
decoder performs 3-2 pulldown to deliver the NTSC-required 29.97 FPS,
but that's not germane to this discussion.

Actually, it is very germane, since 3-2 pulldown is similar
to how some primitive audio pitch/rate changing hardware worked,
by duplicating small time domain frames of audio at a fixed
proportion and rate. Some MPEG decoders do "special effects"
by varying the frame duplicate/drop fractions to slow down
or speed up playback using the same mechanism as for pulldown.

I think he means the change from 2:2 pull-down's natural rate of 30fps

30 fps? What is that the "natural rate" of? I'm not aware of anything
that runs "naturally" at 30 fps.

Isaac

[robert bristow-johnson]

On Aug 26, 10:23 pm, Radium wrote:
On Aug 23, 11:31 am, robert bristow-johnson

wrote:
when i first saw the thread title, that's what i first thought about.
actually, not pitch-shifting but more time-scaling.

That's the opposite of what I'm looking for.

it seems to me
natural that if they were speeding up or slowing down the motion in
the video (which means only for the termporal dimension, not either
"x" or "y"), that would naturally correspond to the same speeding up
or slowing down of tempo (without pitch change) of the audio. if you
twist the knob that makes the actress talk faster (Ms. Motormouth), it
shouldn't be upshifting her pitch to sound like Wendy or Bebe in South
Park.

I want the actress to talk at the same speed, at a lower-pitch, and
finish at the same-time without any low-pass filtering.

okay, so that is a real-time pitch shifter. you can buy those things
and you can buy plug-ins that do it. so what is the "video-
equivalent" to a real-time pitch shifter?

r b-j

(Jerry, i hope i didn't step in a puddle of dung, did i? were you
trying to warn me away?)

[Radium[_4_]]

On Aug 26, 8:43 pm, robert bristow-johnson
wrote:

so what is the "video-
equivalent" to a real-time pitch shifter?

I wish I knew. This is so interesting for me yet so difficult for me
to answer.

What is the "video-equivalent" to a real-time pitch shifter if the
video is B&W? Since I've been giving wrong answers to my questions,
I'll definitely need guidance.

I do know that video-frequency [in B&W video, not color] has two
elements:

1. Temporal frequency

2. Spatial frequency

#1 only applies if the video consists of changing visual signals [such
as a movie or show]

#2 applies to all video signals -- including still images.

In color video, there is the a 3rd element [which is irrelevant to
this discussion] and that relates to the wavelengths of lights in the
video.

[Jerry Avins]

Radium wrote:

...

I want the actress to talk at the same speed, at a lower-pitch, and
finish at the same-time without any low-pass filtering.

That's audio pitch shifting. What has it to do with video? You wanted
something else in the past.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

[Radium[_4_]]

On Aug 26, 9:47 pm, Jerry Avins wrote:

Radium wrote:

I want the actress to talk at the same speed, at a lower-pitch, and
finish at the same-time without any low-pass filtering.

That's audio pitch shifting. What has it to do with video?

I want the video-equivalent of that.