«

Dudley Hanks wrote:
> According to A Wee Bit Too Honest, the garbled image looked kind of like a
> couple of images getting scrambled on a malfunctioning memory card, which
> got me thinking...
>
> I keep my web files on a memory card, so the pic was transferred from the
> netbook to the memory card before being uploaded. In the off chance the
> image got garbled while copying, I've re-uploaded the pic; this time,
> directly from the laptop.
>
> http://www.snaps.blind-apertures.ca/index.html
>
> Just wondering if it's improved, or if it's still jumbled.

Still jumbled. It initially looks like a double exposure but it's not.
The problem is the green (or cyan?) drops out after a few rows of data.

--
Paul Furman
www.edgehill.net
www.baynatives.com

all google groups messages filtered due to spam

"Paul Furman" <paul-@-edgehill.net> wrote in message
news:h524ie$6f5$...
> Dudley Hanks wrote:
>> According to A Wee Bit Too Honest, the garbled image looked kind of like
>> a couple of images getting scrambled on a malfunctioning memory card,
>> which got me thinking...
>>
>> I keep my web files on a memory card, so the pic was transferred from the
>> netbook to the memory card before being uploaded. In the off chance the
>> image got garbled while copying, I've re-uploaded the pic; this time,
>> directly from the laptop.
>>
>> http://www.snaps.blind-apertures.ca/index.html
>>
>> Just wondering if it's improved, or if it's still jumbled.
>
> Still jumbled. It initially looks like a double exposure but it's not. The
> problem is the green (or cyan?) drops out after a few rows of data.
>
> --
> Paul Furman
> www.edgehill.net
> www.baynatives.com
>
> all google groups messages filtered due to spam

Thanks, Paul, I'll have to do a bit of experimenting with it.

I wonder if it is a result of the low light. The software gives more
lighting adjustment when using the video mode than for stills. I hope the
error has something to do with that area. The thought that files are
getting merged concerns me more, since that could have more to do with the
OS than the cam.

Take Care,
Dudley

Dudley Hanks wrote:
> Paul Furman wrote
>> Dudley Hanks wrote:
>>
>>> According to A Wee Bit Too Honest, the garbled image looked kind of like
>>> a couple of images getting scrambled on a malfunctioning memory card,
>>> which got me thinking...
>>>
>>> I keep my web files on a memory card, so the pic was transferred from the
>>> netbook to the memory card before being uploaded. In the off chance the
>>> image got garbled while copying, I've re-uploaded the pic; this time,
>>> directly from the laptop.
>>>
>>> http://www.snaps.blind-apertures.ca/index.html
>>>
>>> Just wondering if it's improved, or if it's still jumbled.
>> Still jumbled. It initially looks like a double exposure but it's not. The
>> problem is the green (or cyan?) drops out after a few rows of data.
>
> Thanks, Paul, I'll have to do a bit of experimenting with it.
>
> I wonder if it is a result of the low light. The software gives more
> lighting adjustment when using the video mode than for stills. I hope the
> error has something to do with that area. The thought that files are
> getting merged concerns me more, since that could have more to do with the
> OS than the cam.

Looks like the data got corrupted somehow: malfunctioning memory card. I
checked and it's actually the yellow channel that's cut off. That
suggests some problem with the jpeg compression:

http://www.impulseadventure.com/phot...lor-space.html
"The human eye has a frequency response that suggests a strong
sensitivity to high-frequency luminance (brightness) and a weak
sensitivity to high-frequency chrominance (color information). Realizing
this, an optimized compression scheme would apply less compression to
the luminance detail (i.e. higher quality, lower loss) than the
chrominance detail.

To accomplish this, the JPEG compression scheme begins with a color
space conversion from RGB (Red - Green - Blue) into YCbCr (Luminance -
Blue/Yellow - Red/Green) (also called YCrCb by some). This conversion
takes the three standard channels (RGB) and maps them into a different
representation that is based on a luminance (brightness) channel and two
opposing color channels.
RGB color space conversion to YCbCr

Having done this conversion step, the JPEG image compression algorithm
can then apply more compression to the color information channels than
the luminance information and yet still arrive at an acceptable
resulting image quality.

The most significant savings in JPEG compression come from the
truncation or elimination of high-frequency detail (through a process
called quantization). Low-frequency information is preserved, while
detail at higher frequencies is progressively discarded in greater
amounts as the frequency increases.

If JPEG compression operated on RGB data instead of YCbCr data, one
would not be able to discard as much of the higher frequency content
without causing a noticeable loss in image quality. Some studies have
compared the suitability of other color spaces (e.g. RGB, HSV, Lab,
etc.) for image compression and have demonstrated that YCbCr is a very
suitable choice (at least for human observation of natural photos)."

--
Paul Furman
www.edgehill.net
www.baynatives.com

all google groups messages filtered due to spam

"Paul Furman" <paul-@-edgehill.net> wrote in message
news:h527t2$onl$...
> Dudley Hanks wrote:
>> Paul Furman wrote
>>> Dudley Hanks wrote:
>>>
>>>> According to A Wee Bit Too Honest, the garbled image looked kind of
>>>> like a couple of images getting scrambled on a malfunctioning memory
>>>> card, which got me thinking...
>>>>
>>>> I keep my web files on a memory card, so the pic was transferred from
>>>> the netbook to the memory card before being uploaded. In the off
>>>> chance the image got garbled while copying, I've re-uploaded the pic;
>>>> this time, directly from the laptop.
>>>>
>>>> http://www.snaps.blind-apertures.ca/index.html
>>>>
>>>> Just wondering if it's improved, or if it's still jumbled.
>>> Still jumbled. It initially looks like a double exposure but it's not.
>>> The problem is the green (or cyan?) drops out after a few rows of data.
>>
>> Thanks, Paul, I'll have to do a bit of experimenting with it.
>>
>> I wonder if it is a result of the low light. The software gives more
>> lighting adjustment when using the video mode than for stills. I hope
>> the error has something to do with that area. The thought that files are
>> getting merged concerns me more, since that could have more to do with
>> the OS than the cam.
>
> Looks like the data got corrupted somehow: malfunctioning memory card. I
> checked and it's actually the yellow channel that's cut off. That suggests
> some problem with the jpeg compression:
>
> http://www.impulseadventure.com/phot...lor-space.html
> "The human eye has a frequency response that suggests a strong sensitivity
> to high-frequency luminance (brightness) and a weak sensitivity to
> high-frequency chrominance (color information). Realizing this, an
> optimized compression scheme would apply less compression to the luminance
> detail (i.e. higher quality, lower loss) than the chrominance detail.
>
> To accomplish this, the JPEG compression scheme begins with a color space
> conversion from RGB (Red - Green - Blue) into YCbCr (Luminance -
> Blue/Yellow - Red/Green) (also called YCrCb by some). This conversion
> takes the three standard channels (RGB) and maps them into a different
> representation that is based on a luminance (brightness) channel and two
> opposing color channels.
> RGB color space conversion to YCbCr
>
> Having done this conversion step, the JPEG image compression algorithm can
> then apply more compression to the color information channels than the
> luminance information and yet still arrive at an acceptable resulting
> image quality.
>
> The most significant savings in JPEG compression come from the truncation
> or elimination of high-frequency detail (through a process called
> quantization). Low-frequency information is preserved, while detail at
> higher frequencies is progressively discarded in greater amounts as the
> frequency increases.
>
> If JPEG compression operated on RGB data instead of YCbCr data, one would
> not be able to discard as much of the higher frequency content without
> causing a noticeable loss in image quality. Some studies have compared the
> suitability of other color spaces (e.g. RGB, HSV, Lab, etc.) for image
> compression and have demonstrated that YCbCr is a very suitable choice (at
> least for human observation of natural photos)."
>
> --
> Paul Furman
> www.edgehill.net
> www.baynatives.com
>
> all google groups messages filtered due to spam

So, basically, this was a compression problem, possibly brought on (or
exacerbated) by low light. That makes me feel a bit better. I just had to
have a new desktop computer repaired because of HD problems, so I had
visions of long chats with techies again...

I'll do a few runs of shots in varying light conditions and see if the error
can be replicated, or whether it's just a one-off gliche because of some
unique problem the existing light posed to the compression routine.

Thanks, Paul.

Take Care,
Dudley

"Dudley Hanks" <> wrote in message
newsTScm.39044$PH1.18223@edtnps82...
> It's only a webcam...
>
> http://www.snaps.blind-apertures.ca/index.html
>
> Take Care,
> Dudley


I've a webcam on my pet too,
http://homepage.ntlworld.com/whisky-...cam/index.html

well actually it's to check who's trying to go through the cat flap.

Once triggered ,a video clip is recorded for 3 mins. Then I put the clips
together,
playback speed 400-800%

Both the tracks below contain music
http://www.youtube.com/watch?v=IUBgEZ5fteU
http://www.youtube.com/watch?v=gHNeKgu1k34

whisky-dave wrote:
>
> "Dudley Hanks" <> wrote in message
> newsTScm.39044$PH1.18223@edtnps82...
> > It's only a webcam...
> >
> > http://www.snaps.blind-apertures.ca/index.html
> >
> > Take Care,
> > Dudley
>
> I've a webcam on my pet too,
> http://homepage.ntlworld.com/whisky-...cam/index.html
>
> well actually it's to check who's trying to go through the cat flap.

<edited>

Hello, Dave:

If a feline (or any other animal) is using your "cat flap," he shouldn't
be referred to, as a "who." <g>

--
Cordially,
John Turco <>

Paintings Pain and Pun <http://laughatthepain.blogspot.com>

"John Turco" <> wrote in message
news:...
> whisky-dave wrote:
>>
>> "Dudley Hanks" <> wrote in message
>> newsTScm.39044$PH1.18223@edtnps82...
>> > It's only a webcam...
>> >
>> > http://www.snaps.blind-apertures.ca/index.html
>> >
>> > Take Care,
>> > Dudley
>>
>> I've a webcam on my pet too,
>> http://homepage.ntlworld.com/whisky-...cam/index.html
>>
>> well actually it's to check who's trying to go through the cat flap.
>
> <edited>
>
> Hello, Dave:
>
> If a feline (or any other animal) is using your "cat flap," he shouldn't
> be referred to, as a "who." <g>

True, I usually refer to them as either the ginger bastard, or the ginger
bastard with the collar,
or the black bastard.


> Paintings Pain and Pun <http://laughatthepain.blogspot.com>

I noticed the titles of the painting aren't quite as inventive as mine

whisky-dave wrote:
>
> "John Turco" <> wrote in message
> news:...

<edited for brevity>

> > If a feline (or any other animal) is using your "cat flap," he shouldn't
> > be referred to, as a "who." <g>
>
> True, I usually refer to them as either the ginger bastard, or the ginger
> bastard with the collar, or the black bastard.

Hello, Dave:

My, such colorful language! <g>

> > Paintings Pain and Pun <http://laughatthepain.blogspot.com>
>
> I noticed the titles of the painting aren't quite as inventive as mine

That's my younger sister's Web site...she's a pretty good artist, no? Help
her make some extra money, by clicking on the ads.

Please, encourage all of your pals to do so, too. :-J

--
Cordially,
John Turco <>

Paintings Pain and Pun <http://laughatthepain.blogspot.com>