CNN cannot handle sound sync in HD
RickMerrill
same program from CNN in HD has the sound coming
almost a second before the video!
What does that say about the technology or lack of
it in such a powerful organization? Has no one
told them? Do they not watch there own show? Or
is there just no possible fix?
Kimba W Lion
>What does that say about the technology or lack of
>it in such a powerful organization? Has no one
>told them? Do they not watch there own show? Or
>is there just no possible fix?
Powerful organization. Right. They're just commercial stuffers like any other
channel. As long as no one pulls an ad, they'll get around to fixing it
eventually. Viewers will just have to deal with the inconvenience because...
they're such a powerful organization.
Charles Tomaras
"RickMerrill" <rick0....@gmail.com.lessspam> wrote in message
news:j07ng3$nsc$1...@dont-email.me...
Actually the video was a second after the sound and there are many possible
places in the chain between CNN and your television where that could be
happening due to additional video processing delays. The problem could even
conceivably be in YOUR television/home theater setup. I watch CNN HD in
Seattle on Comcast Cable every day of the week and it's not out of sync
here.
Kimba W Lion
>Actually the video was a second after the sound and there are many possible
>places in the chain between CNN and your television where that could be
>happening due to additional video processing delays. The problem could even
>conceivably be in YOUR television/home theater setup. I watch CNN HD in
>Seattle on Comcast Cable every day of the week and it's not out of sync
>here.
I get the impression there's no way to guarantee sync with digital TV
transmission. A local engineer said he only had time to sync the video and
audio on their subchannel once in the morning, but it would drift by the end
of each day. Sounds crazy, I know.
UCLAN
> "RickMerrill"<rick0....@gmail.com.lessspam> wrote in message
> news:j07ng3$nsc$1...@dont-email.me...
>> It is 7:04 pm EST and the CNN in SD is ok, but the
>> same program from CNN in HD has the sound coming
>> almost a second before the video!
>
> Actually the video was a second after the sound
How is "the sound coming almost a second before the video" different
from "the video was a second after the sound" ??
me again
> "Charles Tomaras"<tom...@tomaras.com> wrote:
>
...
> I get the impression there's no way to guarantee sync with digital TV
> transmission. A local engineer said he only had time to sync the video and
> audio on their subchannel once in the morning, but it would drift by the end
> of each day. Sounds crazy, I know.
In a number of components there are separate streams processing video frames
and audio segments each with its own delays. You would THINK that a dropped
video frame would put the video sooner, but video errors try to get "corrected"
and that makes the video later.
me again
I guess it is hard to tell which is "actual" ;-)
Charles Tomaras
"Kimba W Lion" <noreplie...@norepliesbyemail.invalid> wrote in message
news:32ov275vhjhedd82e...@4ax.com...
It's gotten much better over the years. My first digital experience was
early off air broadcasts through a Panasonic tuner outputting NTSC to my old
Pioneer Elite 16:9 SD NTSC television. There were more sync issues than I
could shake a stick at. I had a Denon receiver at the time with the ability
to delay the sound up to 100 ms and I had to crank that sucker all around
all the time to be satisfied. Today I rarely notice sync issues.
Charles Tomaras
"UCLAN" <UC...@invalid.net> wrote in message
news:99b36e...@mid.individual.net...
Because it's a more accurate description of what is happening. It's the
video that is delayed. The audio has not been advanced in time.
If your alarm clock is set for 5am and you don't wake up until 5:30am I
suppose you could say your alarm went off too soon but I think it's more
accurate to say you overslept.
UCLAN
>> How is "the sound coming almost a second before the video" different
>> from "the video was a second after the sound" ??
>
> Because it's a more accurate description of what is happening. It's the
> video that is delayed. The audio has not been advanced in time.
LOL.
"The sound coming almost a second before the video" in no way implies
that the audio has been advanced in time. Nice rationalization.
http://sp.life123.com/bm.pix/what-is-tap-dancing.s600x600.jpg
Charles Tomaras
> On 7/27/2011 9:38 PM, Charles Tomaras wrote:
>
>>> How is "the sound coming almost a second before the video" different
>>> from "the video was a second after the sound" ??
>>
>> Because it's a more accurate description of what is happening. It's the
>> video that is delayed. The audio has not been advanced in time.
>
> LOL.
>
> "The sound coming almost a second before the video" in no way implies
> that the audio has been advanced in time.
Well..however you want to look at it...the audio is generally far less
delayed than the video when dealing with digital video recording and
broadcasting. Just wanted to make that clear to the original poster who
didn't seem to understand the physics of the sync problem from his full
description and laying of blame.
me again
Sorry, what "physics?" And yes, I do blame the broadcaster who lets the cable
company screw up their signal.
Matthew L Martin
Umm... How do you propose that broadcasters force cable companies to do
*anything* other than "must carry"?
Matthew
--
"All you need to start an asylum is an empty room and the right kind of
people". Alexander Bullock ("My Man Godfrey" 1936):
Charles Tomaras
"me again" <rick0....@gmail.spamless> wrote in message
news:j0sibf$eq4$1...@dont-email.me...
Still amazed by people who believe there are lots of people involved in the
broadcast chain of a network. There's most likely a few people on different
shifts at CNN who manage the uplink to the satellite and after that it's out
of their hands. Heck...CNN's field reporters now are also the camera guy,
lighting guy and satellite guy. They edit the story on a laptop and then
they set up a laptop sized satellite uplink device to transmit the story.
Not even a sat truck any more for much of it.
T. Keating
<rick0....@gmail.com.lessspam> wrote:
>It is 7:04 pm EST and the CNN in SD is ok, but the
>same program from CNN in HD has the sound coming
>almost a second before the video!
Excessive video processing perhaps??
Use an HDMI from SAT/cable box to feed HDTV, then useTosh-link from TV
to S.R.S.
That way the HDTV can compenstate for any extra processing it
adds(time wise) to keep the sound in sync.
T. Keating
<rick0....@gmail.com.lessspam> wrote:
>It is 7:04 pm EST and the CNN in SD is ok, but the
>same program from CNN in HD has the sound coming
>almost a second before the video!
Excessive video processing perhaps??
Use an HDMI from SAT/cable box to feed HDTV, then useTos-link from TV
to S.R.S.
That way the HDTV can compenstate for any extra processing it
adds(time wise) to keep the sound in sync.
>
Jan B
wrote:
>On Wed, 20 Jul 2011 19:14:16 -0400, RickMerrill
><rick0....@gmail.com.lessspam> wrote:
>
>>It is 7:04 pm EST and the CNN in SD is ok, but the
>>same program from CNN in HD has the sound coming
>>almost a second before the video!
>
>Excessive video processing perhaps??
>
>Use an HDMI from SAT/cable box to feed HDTV, then useTos-link from TV
>to S.R.S.
>
>That way the HDTV can compenstate for any extra processing it
>adds(time wise) to keep the sound in sync.
>
A few comments:
1) Processing delays in TV:s (for motion compensation) are usually in
the range of 50-100ms (with a few exceptions up to 130 or so ms.
If the delay is close to 1s, it is probably not due to the TV
processing. (Agreed that also a video delay of 50ms should be
compensated in order not to become irritating.)
2) It is not a standard feature in TV:s to pass through digital sound
and output at S/PDIF port (TOS-Link or electrical).
The TOS-Link output is often limited to output the sound from a built
in digital tuner. If sound from the HDMI link is passed through, it is
often limited to 2-channel PCM and will not pass 5.1 (DD, DTS etc).
3) Some TV models have the (optional) HDMI feature to report back to a
surround amplifier what processing delay to use, so that the delay
feature in the surround processor can be set automatically.
Otherwise the surround delay can be set manually (in many, but not all
surround amplifiers.)
/Jan
me again
> On 7/28/2011 4:55 PM, me again wrote:
>> Charles Tomaras wrote:
>>> "UCLAN"<UC...@invalid.net> wrote in message
>>> news:99c8o3...@mid.individual.net...
>>>> On 7/27/2011 9:38 PM, Charles Tomaras wrote:
>>>>
>>>>>> How is "the sound coming almost a second before the video" different
>>>>>> from "the video was a second after the sound" ??
>>>>>
>>>>> Because it's a more accurate description of what is happening. It's the
>>>>> video that is delayed. The audio has not been advanced in time.
>>>>
>>>> LOL.
>>>>
>>>> "The sound coming almost a second before the video" in no way implies
>>>> that the audio has been advanced in time.
>>>
>>> Well..however you want to look at it...the audio is generally far less
>>> delayed than the video when dealing with digital video recording and
>>> broadcasting. Just wanted to make that clear to the original poster who
>>> didn't seem to understand the physics of the sync problem from his full
>>> description and laying of blame.
>>
>> Sorry, what "physics?" And yes, I do blame the broadcaster who lets the
>> cable company screw up their signal.
>
> Umm... How do you propose that broadcasters force cable companies to do *anything*
> other than "must carry"?
There are "paid carry" as well, such as 3ABN.
me again
> On Wed, 20 Jul 2011 19:14:16 -0400, RickMerrill
> <rick0....@gmail.com.lessspam> wrote:
>
>> It is 7:04 pm EST and the CNN in SD is ok, but the
>> same program from CNN in HD has the sound coming
>> almost a second before the video!
>
> Excessive video processing perhaps??
>
> Use an HDMI from SAT/cable box to feed HDTV,
THat IS actually what I do.
then useTosh-link from TV to S.R.S.
Please explain, as none of that parses for me!
> That way the HDTV can compensate for any extra processing it
> adds (time wise) to keep the sound in sync.
The problem is that the sound sync (or lack thereof) CHANGES
depending on the feed (i.e. an SD clip upconverted versus a studio feed).
>> What does that say about the technology or lack of
>> it in such an ... organization? Has no one
Charles Tomaras
>>> it in such an ... organization? Has no one
>>> told them? Do they not watch there own show? Or
>>> is there just no possible fix?
I think this whole sync issue can be summed up quite easily. Yes it's still
an issue at times for a wide variety of reasons that are difficult to fully
reign in. It's getting better all the time. Dead on sync, 100% of the time,
is probably never going to be realized with the current diverse array of
technology encountered from the source to the viewer.
Matthew L Martin
The point your (intentionally?) ignoring is that even if the
broadcasters provided a perfectly synchronized stream to the cable
company, they have no control of what the cable company (or your STB,
receiver, television) might do to it.
Blaming the broadcaster is ignoring the magnitude of the problem.
me again
As a consumer it is impossible for us/me to tell where the problem originates.
Therefore problems that are channel specific belong to the channel originator.
The originator should have the know how to decide where the problem lies.
The place where the cable company creates the problem is if the originator does not
supply the original signal and the cable company has to do analog to digital
conversion or SD downconvert from HD.
The issue I-thought-i-was-seeing was a variation in sync in a single channel -
therefore it could not be fixed at my end.
SAC 441
variables,it looks to me you almost have to have a degree as an audio
process engineer to just iron out the "bugs" (perceived or not) in your
entertainment equipment.Which for a lot of lay people is one reason why
new technology is not adopted for one reason or another.
It is akin to buying one of those Japanese toilets with a panel of 130
buttons on it.Avoid the complexity please and just solve the damned
problem!
Matthew L Martin
You do not know that. Your simplistic view of this issue is apparent.
Your assignment of blame to the signal originator is naive, at best.
It has been explained to you, in simple terms, just how many
opportunities there are for synchronization to be lost. *Every*
processor in the chain can do something different, depending on the
"problem" it is trying to correct. Because you only observe it on one
channel does not mean that the originator of the signal for that channel
caused the problem.
Daniel W. Rouse Jr.
"Matthew L Martin" <mlma...@teranews.com> wrote in message
news:SXhZp.77873$5v5....@newsfe11.iad...
the broadcasters are not providing anywhere near a perfect audio/video sync.
This causes any audio processing from an AVR and/or video processing from an
AVR, set top box, TV, etc. to amplify the already existing problem. Even if
it's close to perfect, it still isn't dead-on absolutely precice timing, and
therefore a sync problem of some type can visually be determined from the
audio vs. the video.
The way to rule out any audio/video processing delays is to turn off any
phase control in the AVR (to disable any AVR speaker channel delays based on
speaker distance), turn off any video enhancement or frame enhancement in
the TV (to eliminate video processing delay or extra frame creation delay),
and then if the problem continues, then problem has been narrowed to either
the source material or the feed (in the case of a cable feed or set top
box).
Once the problem has been narrowed down to either the broadcast side or the
source feed--more often than not, the problem can be narrowed down to the
broadcast side simply by switching channels and noticing a more accurate
(but still not perfect) audio/video sync on that other channel.
In that case, I definitely won't be adjusting speaker distance values to
compensate for the extra audio lag on the broadcast side even moreso if it's
channel specific or show specific--and I'm still using a CRT TV therefore
there is no HD processing lag--when the defect is clearly not at all in the
audio/ video equipment I am using.
Matthew L Martin
I wasn't attempting to address any part of the problem. I was merely
pointing out that one can't blame the entire problem on the signal
originator. The rest of your snipped response only amplified my point.
Were you trying to make a point of your own?
Charles Tomaras
"Daniel W. Rouse Jr." <dwro...@nethere.comNOSPAM> wrote in message
news:VLadnQpFjITRYKjT...@nethere.com...
>
> The way to rule out any audio/video processing delays is to turn off any
> phase control in the AVR (to disable any AVR speaker channel delays based
> on speaker distance), turn off any video enhancement or frame enhancement
> in the TV (to eliminate video processing delay or extra frame creation
> delay), and then if the problem continues, then problem has been narrowed
> to either the source material or the feed (in the case of a cable feed or
> set top box).
>
> Once the problem has been narrowed down to either the broadcast side or
> the source feed--more often than not, the problem can be narrowed down to
> the broadcast side simply by switching channels and noticing a more
> accurate (but still not perfect) audio/video sync on that other channel.
>
> In that case, I definitely won't be adjusting speaker distance values to
> compensate for the extra audio lag on the broadcast side even moreso if
> it's channel specific or show specific--and I'm still using a CRT TV
> therefore there is no HD processing lag--when the defect is clearly not at
> all in the audio/ video equipment I am using.
Can also be a 1080i source on a native 720p television etc etc. Vizio
processes that in a different way than Samsung does as do all of the
manufactures. Or you could have the cable box doing the conversion and
outputting 720p or 1080i. There are lots of places these problems can hide.
Good news is the sync problems are less and less these days and at my house
they have disappeared almost completely in the last couple of years.
Jan B
<dwro...@nethere.comNOSPAM> wrote:
...
>In that case, I definitely won't be adjusting speaker distance values to
>compensate for the extra audio lag on the broadcast side even moreso if it's
>channel specific or show specific--and I'm still using a CRT TV therefore
>there is no HD processing lag--when the defect is clearly not at all in the
>audio/ video equipment I am using.
I just like to point out that the speaker distance delays available in
the surround amplifiers have had a limited range to 10m (about 30ms).
According to EBU studies a common threshold where most of us get
irritated over bad audio sync is -40ms (ahead of video) and +60ms
(after the video)..
The global audio delay feature built into many surround amplifers have
often a range of 0 to +200ms.
So in order to have the possibility to correct (certain events) when
the "broadcasting side" delivers the video ahead of the souund it is
actually good to have a TV that adds video delay (up to say 100ms).
Then the audio delay feature can compensate in both directions.
(Even though it is annoying that we have to bother with these
adjustments.)
/Jan
RickMerrill
Matthew my boy, you should not jump to conclusions. The goal is to get <somebody> to
figure out where the problem is coming from. One way is to get the producer to push on
the cable company. THere are multiple soucres of sync problems and they change all the time.
Matthew L Martin
> Matthew L Martin wrote:
--8<---8<---8<------>8--->8--->8---
>>
>> You do not know that. Your simplistic view of this issue is apparent.
>> Your assignment of blame to the signal originator is naive, at best.
>>
>> It has been explained to you, in simple terms, just how many
>> opportunities there are for synchronization to be lost. *Every*
>> processor in the chain
>> can do something different, depending on the "problem" it is trying to
>> correct. Because you only observe it on one channel does not mean that
>> the
>> originator of the signal for that channel caused the problem.
>>
>> Matthew
>>
>>
>
> Matthew my boy, you should not jump to conclusions. The goal is to get
> <somebody> to
> figure out where the problem is coming from. One way is to get the
> producer to push on
> the cable company. THere are multiple soucres of sync problems and they
> change all the time.
So, in what way did you disagree with my comment?
me again
> On 8/14/2011 7:28 PM, RickMerrill wrote:
>> Matthew L Martin wrote:
>
> --8<---8<---8<------>8--->8--->8---
>
>>>
>>> You do not know that. Your simplistic view of this issue is apparent.
>>> Your assignment of blame to the signal originator is naive, at best.
>>>
>>> It has been explained to you, in simple terms, just how many
>>> opportunities there are for synchronization to be lost. *Every*
>>> processor in the chain
>>> can do something different, depending on the "problem" it is trying to
>>> correct. Because you only observe it on one channel does not mean that
>>> the
>>> originator of the signal for that channel caused the problem.
>>>
>>> Matthew
>>>
>>>
>>
>> Matthew my boy, you should not jump to conclusions. The goal is to get
>> <somebody> to
>> figure out where the problem is coming from. One way is to get the
>> producer to push on
>> change all the time.
>
> So, in what way did you disagree with my comment?
>
> Matthew
>
You are "begging the question" by saying it is too complicated and coming from too
many places. We all know that.
I say the originator, say CNN, has a bigger stake in delivering a synced signal than
either the cable company or the end user.
Matthew L Martin
Are you saying that CNN should send a tech to your house to work the
chain backwards? I do not think that will happen.
CNN is responsible for providing a coherent signal for cable/satellite
distribution, full stop. If something along the delivery chain
(including equipment in your home) screws it up, that is not CNN's fault
nor are they going to spend *any* money trying to fix such a problem. If
you think they are, you are truly living in a fantasy land.
me again
How would I contact them?
me again
"For Viewer Services, tweet us at http://twitter.com/teamcnn
Text CNN (space) and your tip to 772937 (don't forget the space after CNN). Include
your cell phone number if you'd like a call back."
<answers own question>