Sign in with
Sign up | Sign in
Your question

Can someone help "PTravel" make a frame accurate cut with ..

Last response: in Graphics & Displays
Share
Anonymous
February 11, 2005 6:48:17 PM

Archived from groups: rec.video.desktop (More info?)

"PTravel" makes the claim that you can't make frame accurate
cuts in MPEG. (See the thread: "What product do you think is
best for AVI to DVD?") So I finally made this proposal:

> Why don't you use the free trial of VideoReDo
> www.VideoReDo.com to cut up a MPEG file and compare the resulting
> file with the original file; see for yourself.

"PTravel"'s response:

I've experimented with VideoReDo when doing video extraction from my Tivo
(which produces non-DVD compliant mpeg2). VideoReDo did not let me do
frame-accurate edits though, of course, it didn't matter when all I wanted
to do was chop out commercials.

Luck;
Ken
Anonymous
February 11, 2005 6:48:18 PM

Archived from groups: rec.video.desktop (More info?)

"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:kMSdnTbh6LaCtZDfRVn-hg@giganews.com...
> "PTravel" makes the claim that you can't make frame accurate
> cuts in MPEG. (See the thread: "What product do you think is
> best for AVI to DVD?") So I finally made this proposal:
>
> > Why don't you use the free trial of VideoReDo
> > www.VideoReDo.com to cut up a MPEG file and compare the resulting
> > file with the original file; see for yourself.
>
> "PTravel"'s response:
>
> I've experimented with VideoReDo when doing video extraction from my Tivo
> (which produces non-DVD compliant mpeg2). VideoReDo did not let me do
> frame-accurate edits though, of course, it didn't matter when all I wanted
> to do was chop out commercials.

I don't need help with VideoReDo because I have no use for it. As I've
said, I edit video projects, I don't trim commercials out of TV programs
that I've captured using USB toys.

VideoReDo, as well as the other tools you've identifed, are probably fine
for hobbyists who want to compile a DVD of Survivor episodes. They're not
appropriate for anyone doing any serious editing and authoring.

If there's a way to make VideoReDo do frame-accurate edits without rendering
or re-transcoding, that's very nice. It's also of no particular interest to
anyone who wants to create video projects from AVI (you might, btw, look at
the subject line of the thread which was about going from AVI to MPEG).

>
> Luck;
> Ken
>
>
Anonymous
February 12, 2005 3:06:48 AM

Archived from groups: rec.video.desktop (More info?)

Don't forget. There are a lot of people out there who actually do think that
MPEG-2 is somehow a higher quality video than DV. So, the toy maket abounds.

"PTravel" <ptravel@ruyitang.com> wrote in message
news:374t40F5ahd8sU1@individual.net...
>
> "Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
> news:kMSdnTbh6LaCtZDfRVn-hg@giganews.com...
> > "PTravel" makes the claim that you can't make frame accurate
> > cuts in MPEG. (See the thread: "What product do you think is
> > best for AVI to DVD?") So I finally made this proposal:
> >
> > > Why don't you use the free trial of VideoReDo
> > > www.VideoReDo.com to cut up a MPEG file and compare the resulting
> > > file with the original file; see for yourself.
> >
> > "PTravel"'s response:
> >
> > I've experimented with VideoReDo when doing video extraction from my
Tivo
> > (which produces non-DVD compliant mpeg2). VideoReDo did not let me do
> > frame-accurate edits though, of course, it didn't matter when all I
wanted
> > to do was chop out commercials.
>
> I don't need help with VideoReDo because I have no use for it. As I've
> said, I edit video projects, I don't trim commercials out of TV programs
> that I've captured using USB toys.
>
> VideoReDo, as well as the other tools you've identifed, are probably fine
> for hobbyists who want to compile a DVD of Survivor episodes. They're not
> appropriate for anyone doing any serious editing and authoring.
>
> If there's a way to make VideoReDo do frame-accurate edits without
rendering
> or re-transcoding, that's very nice. It's also of no particular interest
to
> anyone who wants to create video projects from AVI (you might, btw, look
at
> the subject line of the thread which was about going from AVI to MPEG).
>
> >
> > Luck;
> > Ken
> >
> >
>
>
Related resources
Anonymous
February 12, 2005 3:06:49 AM

Archived from groups: rec.video.desktop (More info?)

"Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote in
message news:sMbPd.24466$pc5.24380@tornado.tampabay.rr.com...
> Don't forget. There are a lot of people out there who actually do think
> that
> MPEG-2 is somehow a higher quality video than DV. So, the toy maket
> abounds.
>

Your camcorder's DV Quality is of little interest to most. It is only
an intermediate stage on the way to MPEG-2 in a DVD. But you
are right that MPEG-2 is valued by many; for instance; anyone who
makes a DVD, all the major movie studios, the broadcast networks,
cable and satellite systems.

Still if you want to spend many hours turning your "Higher Quality"
DV into DVD compliant MPEG-2 that could be slightly "Better" in
some way, have at it. Me I'll settle for MPEG-2 video captures that
are ready to author into DVDs what, when played, provide video
that looks exactly the same the source.

Luck;
Ken
Anonymous
February 12, 2005 3:06:50 AM

Archived from groups: rec.video.desktop (More info?)

"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:WN6dnQQtqcA_z5DfRVn-jw@giganews.com...
>
> "Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote in
> message news:sMbPd.24466$pc5.24380@tornado.tampabay.rr.com...
> > Don't forget. There are a lot of people out there who actually do think
> > that
> > MPEG-2 is somehow a higher quality video than DV. So, the toy maket
> > abounds.
> >
>
> Your camcorder's DV Quality is of little interest to most.

Sorry, but that makes absolutely no sense. The format is of interest to
anyone who wants to edit video. Mpeg is a delivery format, and not one that
is amenable to editing.

> It is only
> an intermediate stage on the way to MPEG-2 in a DVD.

Well, yes, but that's like saying computers are of no interest to anyone
producing a DVD because they are only an intermediate vehicle on the way to
a television set.

> But you
> are right that MPEG-2 is valued by many; for instance; anyone who
> makes a DVD, all the major movie studios, the broadcast networks,
> cable and satellite systems.

None of the major movie studioes, none of the broadcast networks, and no
other content producers edit projects in mpeg. Cable and satellite are
delivery systems -- their only concern is bandwidth.

>
> Still if you want to spend many hours turning your "Higher Quality"
> DV into DVD compliant MPEG-2 that could be slightly "Better" in
> some way, have at it.

And that's the whole point. It's not "slightly better." It's dramatically
better. Retranscoded mpeg is not broadcast quality. DV-codec-encoded AVI
is above broadcast quality. Some people are happy with VHS quality video --
perhaps you're one of those people.

> Me I'll settle for MPEG-2 video captures that
> are ready to author into DVDs

But cannot be edited like an AVI. Your VideoReDo is not an NLE. It doesn't
do titles, transitions, allow color or gamma corrections, permit
compositing, do insert edits, etc. It's useful for one thing and only one
thing: simple cuts edits of mpeg video.

> what, when played, provide video
> that looks exactly the same the source.

Utter and complete nonsense. The best commercially-produced DVD will not
look exactly the same as the source video. A good transcode of an AVI will
come close, but the differences are easily detectable. A real-time mpeg
capture, retranscoded and compressed by DVD Shrink will not even come
remotely close.

>
> Luck;
> Ken
>
>
>
Anonymous
February 12, 2005 3:06:51 AM

Archived from groups: rec.video.desktop (More info?)

"PTravel" <ptravel@ruyitang.com> wrote in message
news:3754s9F58s43iU1@individual.net...
>
> "Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
> news:WN6dnQQtqcA_z5DfRVn-jw@giganews.com...
>>
>> "Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote
>> in
>> message news:sMbPd.24466$pc5.24380@tornado.tampabay.rr.com...
>> > Don't forget. There are a lot of people out there who actually do think
>> > that
>> > MPEG-2 is somehow a higher quality video than DV. So, the toy maket
>> > abounds.
>> >
>>
>> Your camcorder's DV Quality is of little interest to most.
>
> Sorry, but that makes absolutely no sense. The format is of interest to
> anyone who wants to edit video. Mpeg is a delivery format, and not one
> that
> is amenable to editing.
>
>> It is only
>> an intermediate stage on the way to MPEG-2 in a DVD.
>
> Well, yes, but that's like saying computers are of no interest to anyone
> producing a DVD because they are only an intermediate vehicle on the way
> to
> a television set.
>
>> But you
>> are right that MPEG-2 is valued by many; for instance; anyone who
>> makes a DVD, all the major movie studios, the broadcast networks,
>> cable and satellite systems.
>
> None of the major movie studioes, none of the broadcast networks, and no
> other content producers edit projects in mpeg. Cable and satellite are
> delivery systems -- their only concern is bandwidth.
>
>>
>> Still if you want to spend many hours turning your "Higher Quality"
>> DV into DVD compliant MPEG-2 that could be slightly "Better" in
>> some way, have at it.
>
> And that's the whole point. It's not "slightly better." It's
> dramatically
> better. Retranscoded mpeg is not broadcast quality. DV-codec-encoded AVI
> is above broadcast quality. Some people are happy with VHS quality
> video --
> perhaps you're one of those people.
>
>> Me I'll settle for MPEG-2 video captures that
>> are ready to author into DVDs
>
> But cannot be edited like an AVI. Your VideoReDo is not an NLE. It
> doesn't
> do titles, transitions, allow color or gamma corrections, permit
> compositing, do insert edits, etc. It's useful for one thing and only one
> thing: simple cuts edits of mpeg video.
>
>> what, when played, provide video
>> that looks exactly the same the source.
>
> Utter and complete nonsense. The best commercially-produced DVD will not
> look exactly the same as the source video. A good transcode of an AVI
> will
> come close, but the differences are easily detectable. A real-time mpeg
> capture, retranscoded and compressed by DVD Shrink will not even come
> remotely close.
>


You can keep changing the question with all your strawman arguments,
but you still won't and obviously have never in the past TRIED to produce
good results using any process than the one you espouse. You say you
have tried VideoReDo, and it won't make frame accurate cuts. No one
else that has ever tried it would come here and make that claim.

You say there are tremendous problems with the quality of MPEG that
hasn't spent time as AVI. When called on that you say the issue is that
MPEG can't be edited. When directed to the new MPEG frame accurate
editors, you say they can't work or change it to be about adding various
effects. You even had to add DVDShrink to the real-time capture process,
when you know it was mentioned only as a means to allow a slightly over
sized capture to remain usable, not as a routine part of the process.

Your assertion that Direct to DVD Compliant MPEG Capture, cannot
produce results that are indistinguishable from that video source (not the
output of the movie camera on the movie lot, what the guy at home has
as a source.); flies in the face of, not only my experience but many others.

If done properly it is the easiest and fastest way to produce a true copy
of the viewing experience provided by the source. ( Cable, Satellite, VCR,
TV tuner)

It is certainly the case that if you are working with material that
requires the type of editing that would actually require a re-encoding if
it were already DVD compliant MPEG, like your camcorder DV, then
it would be only common sense to edit it in the format it already is in.
This does not make your assertion that "MPEG can't be edited" valid.
It certainly doesn't mean that your characterization of the quality of
MPEG-2 that was made in real-time and without the "benefit" of
having spent time as AVI, is any more valid.

Luck;
Ken
Anonymous
February 12, 2005 6:40:11 AM

Archived from groups: rec.video.desktop (More info?)

"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:aPGdnc_lqM0v6ZDfRVn-vA@giganews.com...
>
> "PTravel" <ptravel@ruyitang.com> wrote in message
> news:3754s9F58s43iU1@individual.net...
>>
>> "Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
>> news:WN6dnQQtqcA_z5DfRVn-jw@giganews.com...
>>>
>>> "Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote
>>> in
>>> message news:sMbPd.24466$pc5.24380@tornado.tampabay.rr.com...
>>> > Don't forget. There are a lot of people out there who actually do
>>> > think
>>> > that
>>> > MPEG-2 is somehow a higher quality video than DV. So, the toy maket
>>> > abounds.
>>> >
>>>
>>> Your camcorder's DV Quality is of little interest to most.
>>
>> Sorry, but that makes absolutely no sense. The format is of interest to
>> anyone who wants to edit video. Mpeg is a delivery format, and not one
>> that
>> is amenable to editing.
>>
>>> It is only
>>> an intermediate stage on the way to MPEG-2 in a DVD.
>>
>> Well, yes, but that's like saying computers are of no interest to anyone
>> producing a DVD because they are only an intermediate vehicle on the way
>> to
>> a television set.
>>
>>> But you
>>> are right that MPEG-2 is valued by many; for instance; anyone who
>>> makes a DVD, all the major movie studios, the broadcast networks,
>>> cable and satellite systems.
>>
>> None of the major movie studioes, none of the broadcast networks, and no
>> other content producers edit projects in mpeg. Cable and satellite are
>> delivery systems -- their only concern is bandwidth.
>>
>>>
>>> Still if you want to spend many hours turning your "Higher Quality"
>>> DV into DVD compliant MPEG-2 that could be slightly "Better" in
>>> some way, have at it.
>>
>> And that's the whole point. It's not "slightly better." It's
>> dramatically
>> better. Retranscoded mpeg is not broadcast quality. DV-codec-encoded
>> AVI
>> is above broadcast quality. Some people are happy with VHS quality
>> video --
>> perhaps you're one of those people.
>>
>>> Me I'll settle for MPEG-2 video captures that
>>> are ready to author into DVDs
>>
>> But cannot be edited like an AVI. Your VideoReDo is not an NLE. It
>> doesn't
>> do titles, transitions, allow color or gamma corrections, permit
>> compositing, do insert edits, etc. It's useful for one thing and only
>> one
>> thing: simple cuts edits of mpeg video.
>>
>>> what, when played, provide video
>>> that looks exactly the same the source.
>>
>> Utter and complete nonsense. The best commercially-produced DVD will not
>> look exactly the same as the source video. A good transcode of an AVI
>> will
>> come close, but the differences are easily detectable. A real-time mpeg
>> capture, retranscoded and compressed by DVD Shrink will not even come
>> remotely close.
>>
>
>
> You can keep changing the question with all your strawman arguments,
> but you still won't and obviously have never in the past TRIED to produce
> good results using any process than the one you espouse. You say you
> have tried VideoReDo, and it won't make frame accurate cuts. No one
> else that has ever tried it would come here and make that claim.

And you're the only person here who would claim that VideoReDo is a NLE.

Ken, who cares if it can produce frame-accurate edits. The bottom line is
this: if you're editing video, use video editing software. VideoReDo is not
substitute for FCP. Premiere, Liquid Edition, or even Studio or Microsoft
MovieMaker.

If you're editing commercials out of TV shows that you've recorded, use
VideoReDo. NLEs are overkill and, clearly, you're unconcerned with quality
anyway.


>
> You say there are tremendous problems with the quality of MPEG that
> hasn't spent time as AVI.

Wrong, wrong, wrong, wrong. Talk about "strawman arguments." That's not
what I said and you know it. Last time:

Trying to edit mpeg for anything other than your Survivor DVD compilations
is pointless because:

1. Transitions, corrections, compositing, etc. require re-rendering which
will SERIOUSLY impact the quality of the video in mpeg.

2. REAL editing programs either don't handle mpeg, or don't handle it well.
REAL editing programs don't do frame-accurate mpeg editing, except, perhaps,
a specialized few. I wouldn't know because REAL editors don't work in mpeg.

> When called on that you say the issue is that
> MPEG can't be edited.

No. Again you're wrong about what I said.

Mpeg can be edited -- just not well.

> When directed to the new MPEG frame accurate
> editors,

What new MPEG frame accurate editors? VideoReDo? Oh, please.

>you say they can't work or change it to be about adding various
> effects.

Wrong again.

You know what? This is really pointless. You have a bug up your butt for
some reason and are more interested in making this about personalities than
about video.

> You even had to add DVDShrink to the real-time capture process,
> when you know it was mentioned only as a means to allow a slightly over
> sized capture to remain usable, not as a routine part of the process.

Hey, you're the one who recommended DVD Shrink which, of course, requires
retranscoding and degradation of the video.

>
> Your assertion that Direct to DVD Compliant MPEG Capture, cannot
> produce results that are indistinguishable from that video source (not the
> output of the movie camera on the movie lot, what the guy at home has
> as a source.); flies in the face of, not only my experience but many
> others.

Then you and many others have very, very, very little experience.
Commercial-quality mpeg is the result of multiple-pass transcoding. The
best realtime hardware transcoders (which are used by the satellite and
cable providers) don't produce output comparable to a commercial DVD.

>
> If done properly it is the easiest and fastest way to produce a true copy
> of the viewing experience provided by the source. ( Cable, Satellite, VCR,
> TV tuner)

See, this is what I'm talking about. You're speaking from the perspective
of someone copying television shows and removing commercials. THAT is not
video editing. I don't doubt that you're satisfied with the quality of
video that you get from programs like VideoReDo and DVD Shrink.

Spend a little time over at rec.video.production and www.dvinfo.net where
the professionals gather and run your theories by them.

>
> It is certainly the case that if you are working with material that
> requires the type of editing that would actually require a re-encoding if
> it were already DVD compliant MPEG, like your camcorder DV, then
> it would be only common sense to edit it in the format it already is in.
> This does not make your assertion that "MPEG can't be edited" valid.


I never said that MPEG can't be edited. I said it can't be edited easily or
well.

> It certainly doesn't mean that your characterization of the quality of
> MPEG-2 that was made in real-time and without the "benefit" of
> having spent time as AVI, is any more valid.

Your mischaracterization of what I said may not mean it, but the reality of
video capture certainly does.

>
> Luck;
> Ken
>
>
>
Anonymous
February 12, 2005 3:02:19 PM

Archived from groups: rec.video.desktop (More info?)

> 2. REAL editing programs either don't handle mpeg, or don't handle it
well.
> REAL editing programs don't do frame-accurate mpeg editing, except,
perhaps,
> a specialized few. I wouldn't know because REAL editors don't work in
mpeg.

And that's a fact. Even using the Main Concept plugin for PP, mpeg editing
is clunky at best.

For simple slicing and dicing of material already encoded into mpeg format,
V-Redo, Womble, etc are fine. And they can, in fact, do frame accurate
edits. But there's no way anyone can say that mpeg'd material is the
preferred format for video editing. Unfortunately, people using the Hauppage
line of products have no choice because _all_ of their captures are hardware
mpeg encoded. Since I use an ATI card, I prefer to capture to Huffyuv avi's,
edit in Premier and encode with Procoder. And I'll match my two-pass VBR
encodes against a five year old hardware encoding algorithm anyday of the
week.

> You know what? This is really pointless. You have a bug up your butt for
> some reason and are more interested in making this about personalities
than
> about video.

The Hauppage/Video-Redo/Vegas crowd in here can be downright arrogant
sometimes.

> > If done properly it is the easiest and fastest way to produce a true
copy
> > of the viewing experience provided by the source. ( Cable, Satellite,
VCR,
> > TV tuner)

Easiest and fastest usually do not add up to quality.
Anonymous
February 12, 2005 9:41:58 PM

Archived from groups: rec.video.desktop (More info?)

"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote in message
news:GzqPd.6014$a06.1863@bignews1.bellsouth.net...
>> 2. REAL editing programs either don't handle mpeg, or don't handle it
> well.
>> REAL editing programs don't do frame-accurate mpeg editing, except,
> perhaps,
>> a specialized few. I wouldn't know because REAL editors don't work in
> mpeg.
>
> And that's a fact. Even using the Main Concept plugin for PP, mpeg editing
> is clunky at best.
>
> For simple slicing and dicing of material already encoded into mpeg
> format,
> V-Redo, Womble, etc are fine. And they can, in fact, do frame accurate
> edits. But there's no way anyone can say that mpeg'd material is the
> preferred format for video editing.


And No One ever said anything different, Except "PTravel" saying
that you can't do frame accurate edits.



> Unfortunately, people using the Hauppage
> line of products have no choice because _all_ of their captures are
> hardware
> mpeg encoded. Since I use an ATI card, I prefer to capture to Huffyuv
> avi's,
> edit in Premier and encode with Procoder. And I'll match my two-pass VBR
> encodes against a five year old hardware encoding algorithm anyday of the
> week.
>
>> You know what? This is really pointless. You have a bug up your butt
>> for
>> some reason and are more interested in making this about personalities
> than
>> about video.
>
> The Hauppage/Video-Redo/Vegas crowd in here can be downright arrogant
> sometimes.
>
>> > If done properly it is the easiest and fastest way to produce a true
> copy
>> > of the viewing experience provided by the source. ( Cable, Satellite,
> VCR,
>> > TV tuner)
>
> Easiest and fastest usually do not add up to quality.
>

Just who is being arrogant here? No one has said the way you
capture, edit, encode, author, or burn DVDs produces bad results.
No one on this side of the issue is saying you can't edit AVI.
We aren't saying the results that you see every day are impossible,
or the result of some lower standard of "Quality", as your side
often does.

I myself have often recommended your old, slow, method of
capture and DVD production to those who are working with
unedited material.

With the process that I and many others use, I save up some
of the video entertainment that arrives at my house, into DVD
format. When I playback that archived video it looks and
sounds in no way inferior or different from the way it looked
when it first arrived. Your side keeps saying this is a lie, that
it can't be, that there must be some "Degradation" that I am
unwilling to acknowledge. Isn't That arrogant?

It is your side that is saying, that your way is the Only REAL
Way. You are in effect saying that since we are not trying to
make movies from scratch, our faster and easier methods
don't count and must be inferior to your methods, just
because they aren't applicable to movie making. How
arrogant is that?

If "PTravel" had said you can't do a crossfade transition in
MPEG, I would have let it go. Those with the objective of
saving up professionally edited material, never need to do
such editing. But his false claims that frame accurate editing
of MPEG would require the introduction of horrendous
degradation, because (first the whole video then even if a
few frames) must be "re-transcoded", do impact on our
efforts.

All in all it appears to me that you old guard, the only way
to get good results is my way crowd, are the ones with
your noes in the air.

We will never agree, but the issue is here in this thread
for all to see, and at least one false claim hasn't gone
unanswered.

Luck;
Ken
Anonymous
February 13, 2005 11:35:10 AM

Archived from groups: rec.video.desktop (More info?)

PTRAVEL, Ken is kid, I think. Pretty much of a novice. I think you're
wasting your time.

Ken, Any compressed image is NOT ever going to be better than its
source.

I highly DOUBT that video-re-do does frame accurate MPEG cuts. More
probably just cuts at I Frames. Its a toy anyway.. who cares. ?
Anonymous
February 13, 2005 11:35:11 AM

Archived from groups: rec.video.desktop (More info?)

"Ken Maltby" wrote ...
> You express the attitude, reverence for the truth, and that
> amazing ability to evaluate things you have obviously never
> tried, that marks the rest of your crowd. What I actually said
> is there for all to read.

Ken, take a deep breath and look at that statement in a mirror.
Your worldview appears to be remarkably limited to what you
see on your OTA/cable/sattelite. Go down to a TV station and
see what real video looks like before it has the life compressed
out of it. It will blow your mind and completely change your
attitude.

In a way you are correct that MPEG compression and even editing
of such is a "new generation" and is rejected summarily by many
of us. But what you don't seem to realize is what a remarkable
step DOWN in quality and functionality MPEG encoding and
"editing" is. Perhaps it is excusable if you have only MPEG
compressed video to work with.

TV shows go through a long production and distribution chain
which includes MPEG compression if you are watching cable
or sattelite. We attempt to store and edit video at the highest
quality available and hold off MPEG compression until the
last possible moment in order to preserve enough quality that
the video will be good enough for you to consider it worth
archiving and "editing" when it finally gets to your house.
Anonymous
February 13, 2005 12:38:46 PM

Archived from groups: rec.video.desktop (More info?)

Given the GOP structure of VBR or CBR MPEG-2, whether the video is captured
to or encoded to that format, frame accurate editing is not - and I repeat
NOT possible. The program and the manufacturer that claims this frame
accurate editing is in short stretching the truth, and anyone who believes
it is easily fooled.

MPEG-2 when encoded, whether using VBR or CBR to a GOP with the IBBP frame
structure has full frames only about 1/3 of the time. Every frame in between
I frames is made up of information from subsequent and previous frames in
the stream. These "so-called" frame accurate MPEG-2 editing packages may
have the ability to take the information from the BBP frames to create a
pseudo "full frame" but that is still NOT frame accurate. The only way these
programs could come near to frame accurate editing would be to negate the
BBP frames near the cut in favor of the nearest I frame.

If this is not the case then the whole structure of the GOP would be trashed
by the cut. The GOP cannot have a structure of IIBPIPBIPPI, which is what
you get if true frame accurate editing is allowed. It's purely simple. The
MPEG GOP standard is 15 and is divisable by 3. The explanation below (which
is information from the Motion Pictures Engineers Group proper) shows that
it is impossible to do frame accurate editing on MPEG files with the IBBP
frame structure. ONLY I frame MPEG can be editing in frame accurate mode.
The GOP (Group of Pictures) Pattern is the arrangement of frames in an MPEG
video stream. The GOP consists of a variable number of I, B, and P frames.
There is not a standard way of formatting the groups, and different
manufacturers may choose quite varied GOP arrangement. One may use I, B, and
P frames in specific groups arranged as IBBP, while another may use an
arrangement which incorporates on I and P frames, and others I-frames only.

The GOP interval and size will determine the pattern of the frame types in
the MPEG stream. It is common practice to keep the number of pictures in the
GOP at a number that is evenly divisible by the interval. So, if the
interval is 3 then the GOP has to be divisible by 3. MPEG has a standard GOP
of 15 with the interval of 3.

Using an IBBP arrangement will yield a low data rate video with the best
quality. When you use I-frames only the quality is much higher as is the
data rate also higher. When you want to keep bandwidth to a minimum and
maintain quality it is good to use the IBBP arrangement as the GOP.


"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:aPGdnc_lqM0v6ZDfRVn-vA@giganews.com...
>
> "PTravel" <ptravel@ruyitang.com> wrote in message
> news:3754s9F58s43iU1@individual.net...
> >
> > "Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
> > news:WN6dnQQtqcA_z5DfRVn-jw@giganews.com...
> >>
> >> "Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote
> >> in
> >> message news:sMbPd.24466$pc5.24380@tornado.tampabay.rr.com...
> >> > Don't forget. There are a lot of people out there who actually do
think
> >> > that
> >> > MPEG-2 is somehow a higher quality video than DV. So, the toy maket
> >> > abounds.
> >> >
> >>
> >> Your camcorder's DV Quality is of little interest to most.
> >
> > Sorry, but that makes absolutely no sense. The format is of interest to
> > anyone who wants to edit video. Mpeg is a delivery format, and not one
> > that
> > is amenable to editing.
> >
> >> It is only
> >> an intermediate stage on the way to MPEG-2 in a DVD.
> >
> > Well, yes, but that's like saying computers are of no interest to anyone
> > producing a DVD because they are only an intermediate vehicle on the way
> > to
> > a television set.
> >
> >> But you
> >> are right that MPEG-2 is valued by many; for instance; anyone who
> >> makes a DVD, all the major movie studios, the broadcast networks,
> >> cable and satellite systems.
> >
> > None of the major movie studioes, none of the broadcast networks, and no
> > other content producers edit projects in mpeg. Cable and satellite are
> > delivery systems -- their only concern is bandwidth.
> >
> >>
> >> Still if you want to spend many hours turning your "Higher Quality"
> >> DV into DVD compliant MPEG-2 that could be slightly "Better" in
> >> some way, have at it.
> >
> > And that's the whole point. It's not "slightly better." It's
> > dramatically
> > better. Retranscoded mpeg is not broadcast quality. DV-codec-encoded
AVI
> > is above broadcast quality. Some people are happy with VHS quality
> > video --
> > perhaps you're one of those people.
> >
> >> Me I'll settle for MPEG-2 video captures that
> >> are ready to author into DVDs
> >
> > But cannot be edited like an AVI. Your VideoReDo is not an NLE. It
> > doesn't
> > do titles, transitions, allow color or gamma corrections, permit
> > compositing, do insert edits, etc. It's useful for one thing and only
one
> > thing: simple cuts edits of mpeg video.
> >
> >> what, when played, provide video
> >> that looks exactly the same the source.
> >
> > Utter and complete nonsense. The best commercially-produced DVD will
not
> > look exactly the same as the source video. A good transcode of an AVI
> > will
> > come close, but the differences are easily detectable. A real-time mpeg
> > capture, retranscoded and compressed by DVD Shrink will not even come
> > remotely close.
> >
>
>
> You can keep changing the question with all your strawman arguments,
> but you still won't and obviously have never in the past TRIED to produce
> good results using any process than the one you espouse. You say you
> have tried VideoReDo, and it won't make frame accurate cuts. No one
> else that has ever tried it would come here and make that claim.
>
> You say there are tremendous problems with the quality of MPEG that
> hasn't spent time as AVI. When called on that you say the issue is that
> MPEG can't be edited. When directed to the new MPEG frame accurate
> editors, you say they can't work or change it to be about adding various
> effects. You even had to add DVDShrink to the real-time capture process,
> when you know it was mentioned only as a means to allow a slightly over
> sized capture to remain usable, not as a routine part of the process.
>
> Your assertion that Direct to DVD Compliant MPEG Capture, cannot
> produce results that are indistinguishable from that video source (not the
> output of the movie camera on the movie lot, what the guy at home has
> as a source.); flies in the face of, not only my experience but many
others.
>
> If done properly it is the easiest and fastest way to produce a true
copy
> of the viewing experience provided by the source. ( Cable, Satellite, VCR,
> TV tuner)
>
> It is certainly the case that if you are working with material that
> requires the type of editing that would actually require a re-encoding if
> it were already DVD compliant MPEG, like your camcorder DV, then
> it would be only common sense to edit it in the format it already is in.
> This does not make your assertion that "MPEG can't be edited" valid.
> It certainly doesn't mean that your characterization of the quality of
> MPEG-2 that was made in real-time and without the "benefit" of
> having spent time as AVI, is any more valid.
>
> Luck;
> Ken
>
>
>
Anonymous
February 13, 2005 12:38:47 PM

Archived from groups: rec.video.desktop (More info?)

"Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote in
message news:GeFPd.31046$pc5.23046@tornado.tampabay.rr.com...
> Given the GOP structure of VBR or CBR MPEG-2, whether the video is
> captured
> to or encoded to that format, frame accurate editing is not - and I repeat
> NOT possible. The program and the manufacturer that claims this frame
> accurate editing is in short stretching the truth, and anyone who believes
> it is easily fooled.
>
> MPEG-2 when encoded, whether using VBR or CBR to a GOP with the IBBP frame
> structure has full frames only about 1/3 of the time. Every frame in
> between
> I frames is made up of information from subsequent and previous frames in
> the stream.

----From here to the next break is this poster demonstrating that -he-
doesn't
know how it can be done, therefore he can't accept that anyone else has done
it. I am sure there would be problems if the Frame Accurate MPEG Editors
actually worked the way this poster seems to think that they
do. ------------

>These "so-called" frame accurate MPEG-2 editing packages may
> have the ability to take the information from the BBP frames to create a
> pseudo "full frame" but that is still NOT frame accurate. The only way
> these
> programs could come near to frame accurate editing would be to negate the
> BBP frames near the cut in favor of the nearest I frame.
>
> If this is not the case then the whole structure of the GOP would be
> trashed
> by the cut. The GOP cannot have a structure of IIBPIPBIPPI, which is what
> you get if true frame accurate editing is allowed. It's purely simple. The
> MPEG GOP standard is 15 and is divisable by 3. The explanation below
> (which
> is information from the Motion Pictures Engineers Group proper) shows that
> it is impossible to do frame accurate editing on MPEG files with the IBBP
> frame structure. ONLY I frame MPEG can be editing in frame accurate mode.

This may come as a shock, but the standard only sets the upper limit
for GOP size (and current practice has extended that dramatically, check out
MPEG4 and there is an extended DVD (xDVD) that plays in most DVD
players, See the TMPGEnc 3.0 XPress help files). All the cuts I've seen
with VideoReDo result in two smaller GOP, each with a normal structure.
By the way the PAL standard has the 15 frame per GOP limit with NTSC
it's 18. There is no restriction, in the standards or in practice, to any
smaller
GOP all the way down to the I Frame only variety.

Let Me speculate for a minute, you have never used VideoReDo or any
other MPEG editor that "claims" to do frame accurate cuts; have you?


---- All the below is mostly quite accurate, if irrelevent. --------------

> The GOP (Group of Pictures) Pattern is the arrangement of frames in an
> MPEG
> video stream. The GOP consists of a variable number of I, B, and P frames.
> There is not a standard way of formatting the groups, and different
> manufacturers may choose quite varied GOP arrangement. One may use I, B,
> and
> P frames in specific groups arranged as IBBP, while another may use an
> arrangement which incorporates on I and P frames, and others I-frames
> only.
>
> The GOP interval and size will determine the pattern of the frame types in
> the MPEG stream. It is common practice to keep the number of pictures in
> the
> GOP at a number that is evenly divisible by the interval. So, if the
> interval is 3 then the GOP has to be divisible by 3. MPEG has a standard
> GOP
> of 15 with the interval of 3.
>
> Using an IBBP arrangement will yield a low data rate video with the best
> quality. When you use I-frames only the quality is much higher as is the
> data rate also higher. When you want to keep bandwidth to a minimum and
> maintain quality it is good to use the IBBP arrangement as the GOP.
>
----------------------------

If it were true that : "The program and the manufacturer that claims
this frame accurate editing is in short stretching the truth, and anyone who
believes it is easily fooled." Then the fact that the MPEG that I cut that
way, starts or ends on the exact frame that I want, must be a really good
illusion. If we are back to "it's not a REAL frame accurate cut" because
it wasn't done your way, I give up.

Luck;
Ken
Anonymous
February 13, 2005 4:29:49 PM

Archived from groups: rec.video.desktop (More info?)

> TV shows go through a long production and distribution chain
> which includes MPEG compression if you are watching cable
> or sattelite. We attempt to store and edit video at the highest
> quality available and hold off MPEG compression until the
> last possible moment in order to preserve enough quality that
> the video will be good enough for you to consider it worth
> archiving and "editing" when it finally gets to your house.

When I was making the transition from C-Band analog satellite TV reception
to the mpeg'd format of Dish Network, I was surprised that I generally could
not tell the difference in "quality" on my 32" Sony XBR. Sure, you could
tell on certain situations where there's fast motion and low light levels,
but for casual viewing they were both virtually identical, to me... on my
system.

Using the method I've previously described, I burned a DVD of material I had
captured and played it back on my system. It was easily watchable. I then
went over to my brother's house and viewed it on his 55" monster. It was
almost unwatchable. Now I had previously done this with my C-band system and
the shows were virtually indistinguishable from his normal OTA picture. So I
had to conclude that even though _I_ couldn't easily discern the apparent
"quality" differences between the two transmission systems on _my_ system
didn't mean it wouldn't be apparent on another system.

So what's the point of this long-winded post? "Quality" is determined not
only by the "quality" of the original signal but in the manner in which it
is displayed as well.
Anonymous
February 13, 2005 8:21:07 PM

Archived from groups: rec.video.desktop (More info?)

"Richard Crowley" <rcrowley7@xprt.net> wrote in message
news:110us82cpk7ng4c@corp.supernews.com...
> "Ken Maltby" wrote ...
>> You express the attitude, reverence for the truth, and that amazing
>> ability to evaluate things you have obviously never tried, that marks the
>> rest of your crowd. What I actually said is there for all to read.
>
> Ken, take a deep breath and look at that statement in a mirror.
> Your worldview appears to be remarkably limited to what you see on your
> OTA/cable/sattelite. Go down to a TV station and see what real video looks
> like before it has the life compressed out of it. It will blow your mind
> and completely change your attitude.
>

Well the fact still remains that, "life compressed out of it" or
not, that is what most of us have for source video. It is the
"Quality" of video that we non-professionals have access to,
at home. It is to this that we must make our comparisons.

I am also curious how capturing the analog signals of such
inferior sources in the less compressed AVI DV format will
allow you to, in the end, produce a DVD that is "better"
than this source. Just how much "better" than this source
can come from using your techniques? I know that using a
multi-pass encoding technique you can do a better job
compressing the source into a smaller MPEG, but the
source (the analog signal that you encoded as AVI)
contained only so much image data.

If my process gets enough of the analog input's image
data properly stored, so that on playback, it is virtually
identical to how it looks when the analog signal is
played directly; How much more of the analog signal's
image can your process retain?

> In a way you are correct that MPEG compression and even editing
> of such is a "new generation" and is rejected summarily by many
> of us. But what you don't seem to realize is what a remarkable
> step DOWN in quality and functionality MPEG encoding and "editing" is.
> Perhaps it is excusable if you have only MPEG
> compressed video to work with.
>

I am very aware of the effects of compression on video. I
would remind you though, that to make a DVD you must
compress the video. With the Real-time capture to DVD
compliant MPEG approach there is only the one encoding,
one compression. With your approach isn't it that the
analog signal is first encoded as AVI, image altering editing
applied, and then transcoded to DVD compliant MPEG?

As to the issue of the "functionality" of MPEG Editing;
if it provides all that is needed, in this case Frame accurate
cuts, then it -is- functional. Keeping in mind the nature
of the sources coming into the home and that most of
us are capturing, Professionally edited material with
commercials and other unwanted parts; the Only editing
required is to cut out some material.



> TV shows go through a long production and distribution chain which
> includes MPEG compression if you are watching cable or sattelite. We
> attempt to store and edit video at the highest
> quality available and hold off MPEG compression until the
> last possible moment in order to preserve enough quality that
> the video will be good enough for you to consider it worth
> archiving and "editing" when it finally gets to your house.

Yes and I'm sure we all appreciate the Professional
Videographer's efforts, but that's part of the point, we are
working with their Output, not their Source.

If I can convert the analog sources that I have coming
into my home, into a DVD that, when played back looks
just the same as it looked when it arrived, then I've done
all that I want. Then the procedure I use will have done
all that I can ask of it. That it does this in Real-time, is a
much appreciated bonus.

If I were making a movie, I would certainly be using a
process similar to yours. But as long as I am just saving
up entertainment, that has been professionally produced,
and edited, the faster,easier and just as good as it looked
when I got it approach is, on balance, at least as good as
yours.

Luck;
Ken
Anonymous
February 13, 2005 8:52:50 PM

Archived from groups: rec.video.desktop (More info?)

"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote in message
news:N_MPd.5296$u16.4769@bignews6.bellsouth.net...
>> TV shows go through a long production and distribution chain
>> which includes MPEG compression if you are watching cable
>> or sattelite. We attempt to store and edit video at the highest
>> quality available and hold off MPEG compression until the
>> last possible moment in order to preserve enough quality that
>> the video will be good enough for you to consider it worth
>> archiving and "editing" when it finally gets to your house.
>
> When I was making the transition from C-Band analog satellite TV reception
> to the mpeg'd format of Dish Network, I was surprised that I generally
> could
> not tell the difference in "quality" on my 32" Sony XBR. Sure, you could
> tell on certain situations where there's fast motion and low light levels,
> but for casual viewing they were both virtually identical, to me... on my
> system.
>
> Using the method I've previously described, I burned a DVD of material I
> had
> captured and played it back on my system. It was easily watchable. I then
> went over to my brother's house and viewed it on his 55" monster. It was
> almost unwatchable. Now I had previously done this with my C-band system
> and
> the shows were virtually indistinguishable from his normal OTA picture. So
> I
> had to conclude that even though _I_ couldn't easily discern the apparent
> "quality" differences between the two transmission systems on _my_ system
> didn't mean it wouldn't be apparent on another system.
>
> So what's the point of this long-winded post? "Quality" is determined not
> only by the "quality" of the original signal but in the manner in which it
> is displayed as well.
>

Agreed, and interesting, but you used the same capture
procedures for both trials, right? It wasn't one was properly
captured directly to MPEG and the other properly captured
to AVI first then encoded to MPEG.

One wasn't MPEG that had been Cut when it was AVI and
the other cut with a frame accurate MPEG editor?

I have a "SharpVision" Projector that lets me view any of
my video on a 100" screen, in a darkened room. Under
that screen I have a 27" S-Video capable monitor/TV. I
can route the same S-Video signal to both. When I do so
with any analog (S-Video) source the image is a little softer
on the projection screen than it is on the monitor and the
blacks could be a little blacker. When I playback one of
my "homemade" DVDs I see the same effects looking from
the monitor to the projection screen. I haven't seen any new
effects, as you describe, looking at the 100" screen.

Luck;
Ken
Anonymous
February 13, 2005 11:07:07 PM

Archived from groups: rec.video.desktop (More info?)

> Agreed, and interesting, but you used the same capture
> procedures for both trials, right? It wasn't one was properly

Yes, the only variable was one source was C-Band analog and the other was
mpeg'd.

> captured directly to MPEG and the other properly captured
> to AVI first then encoded to MPEG.
> One wasn't MPEG that had been Cut when it was AVI and
> the other cut with a frame accurate MPEG editor?

As I said before I don't capture directly to mpeg, I capture to Huffyuv avi
and then encode with Procoder with 2 pass VBR. I don't believe that a 5
year old encoding algorythm hard coded into a chip is going to give the same
"quality" as a dual pass VBR encode with a current, top quality s/w encoder.
How the footage was edited has absolutely no bearing on how it was
displayed.


> I have a "SharpVision" Projector that lets me view any of
> my video on a 100" screen, in a darkened room. Under
> that screen I have a 27" S-Video capable monitor/TV. I
> can route the same S-Video signal to both. When I do so
> with any analog (S-Video) source the image is a little softer
> on the projection screen than it is on the monitor and the
> blacks could be a little blacker. When I playback one of
> my "homemade" DVDs I see the same effects looking from
> the monitor to the projection screen. I haven't seen any new
> effects, as you describe, looking at the 100" screen.

The _source_ of what you are viewing is the same, that's why you see the
same "effects" on both displays. Now if you're trying to say they both look
exactly the same to you and you can't tell the difference in pixelization
between a 27" monitor and a 100" projection, then I have to question your
ability to perceive video.
Anonymous
February 13, 2005 11:07:08 PM

Archived from groups: rec.video.desktop (More info?)

"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote in message
news:gPSPd.5331$u16.5264@bignews6.bellsouth.net...
>> Agreed, and interesting, but you used the same capture
>> procedures for both trials, right? It wasn't one was properly
>
> Yes, the only variable was one source was C-Band analog and the other was
> mpeg'd.
>

But they weren't even the same source, how's that for a
variable? The only point I could see to that paragraph was
that Dish Network's output can't stand up to being enlarged,
but your C-Band can. In both cases you are taking the
analog signal from the receiver/box and producing the video
using only your technique. It only provides information on
some effect that you notice using your technique. There is no
comparison of the techniques under discussion.


>> captured directly to MPEG and the other properly captured
>> to AVI first then encoded to MPEG.
>> One wasn't MPEG that had been Cut when it was AVI and
>> the other cut with a frame accurate MPEG editor?
>
> As I said before I don't capture directly to mpeg, I capture to Huffyuv
> avi
> and then encode with Procoder with 2 pass VBR. I don't believe that a 5
> year old encoding algorythm hard coded into a chip is going to give the
> same
> "quality" as a dual pass VBR encode with a current, top quality s/w
> encoder.
> How the footage was edited has absolutely no bearing on how it was
> displayed.
>
But how it was edited is a factor in contention, in this thread.

>
>> I have a "SharpVision" Projector that lets me view any of
>> my video on a 100" screen, in a darkened room. Under
>> that screen I have a 27" S-Video capable monitor/TV. I
>> can route the same S-Video signal to both. When I do so
>> with any analog (S-Video) source the image is a little softer
>> on the projection screen than it is on the monitor and the
>> blacks could be a little blacker. When I playback one of
>> my "homemade" DVDs I see the same effects looking from
>> the monitor to the projection screen. I haven't seen any new
>> effects, as you describe, looking at the 100" screen.
>
> The _source_ of what you are viewing is the same, that's why you see the
> same "effects" on both displays. Now if you're trying to say they both
> look
> exactly the same to you and you can't tell the difference in pixelization
> between a 27" monitor and a 100" projection, then I have to question your
> ability to perceive video.
>
To make a Valid comparison the source Must be the same.
What I did and am now saying is that whatever differences there
are between the monitor and the projection, they don't change or
increase when I play one of my DVDs. The same differences
appear when using the analog S-Video signal from my DirecTiVo
DVR as appear when using the S-Video output of my DVD
player as it plays one of my DVDs. No new or more grievous
artifacts appear.

Given that the "Quality" of the DirecTiVo S-Video output, I'm
not surprised that it can be Blown up without problems, this is
also some testament to the "Quality" of the Phillips SAA7114H
A/D and the Broadcom BCM7040 "KFir-II" Encoder Chips.
Combining your and my experience might suggest that the S-Video
output of the DirecTiVo DVR is closer to the analog output of your
C-Band Receiver than it is to that of a Dish Network Box. All
this is interesting, but has little to do with the theme of this thread.

Luck;
Ken
Anonymous
February 14, 2005 4:31:59 PM

Archived from groups: rec.video.desktop (More info?)

> > exactly the same to you and you can't tell the difference in
pixelization
> > between a 27" monitor and a 100" projection, then I have to question
your
> > ability to perceive video.
> >
> To make a Valid comparison the source Must be the same.
> What I did and am now saying is that whatever differences there
> are between the monitor and the projection, they don't change or
> increase when I play one of my DVDs. The same differences

As I said above, based on your posts in this thread I question your ability
to perceive video artifacts that result from mpeg compression.
Anonymous
February 14, 2005 7:55:06 PM

Archived from groups: rec.video.desktop (More info?)

"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote in message
news:N_MPd.5296$u16.4769@bignews6.bellsouth.net...
>> TV shows go through a long production and distribution chain
>> which includes MPEG compression if you are watching cable
>> or sattelite. We attempt to store and edit video at the highest
>> quality available and hold off MPEG compression until the
>> last possible moment in order to preserve enough quality that
>> the video will be good enough for you to consider it worth
>> archiving and "editing" when it finally gets to your house.
>
> When I was making the transition from C-Band analog satellite TV reception
> to the mpeg'd format of Dish Network, I was surprised that I generally
> could
> not tell the difference in "quality" on my 32" Sony XBR. Sure, you could
> tell on certain situations where there's fast motion and low light levels,
> but for casual viewing they were both virtually identical, to me... on my
> system.
>
> Using the method I've previously described, I burned a DVD of material I
> had
> captured and played it back on my system. It was easily watchable. I then
> went over to my brother's house and viewed it on his 55" monster. It was
> almost unwatchable. Now I had previously done this with my C-band system
> and
> the shows were virtually indistinguishable from his normal OTA picture. So
> I
> had to conclude that even though _I_ couldn't easily discern the apparent
> "quality" differences between the two transmission systems on _my_ system
> didn't mean it wouldn't be apparent on another system.
>
> So what's the point of this long-winded post? "Quality" is determined not
> only by the "quality" of the original signal but in the manner in which it
> is displayed as well.


more accurately .. compression artifacts are hidden on smaller TVs.
>
>
Anonymous
February 15, 2005 10:47:35 AM

Archived from groups: rec.video.desktop (More info?)

MPEG-2 and MPEG-4 are not the same, and believe what you want....it's
bullshit.

"Ken Maltby" <kmaltby@sbcglobal.net> wrote in message
news:D PidnQ1nh--TrZLfRVn-1w@giganews.com...
>
> "Digital Video Solutions" <video@digitalvideosolutionsNOSPAM.com> wrote in
> message news:GeFPd.31046$pc5.23046@tornado.tampabay.rr.com...
> > Given the GOP structure of VBR or CBR MPEG-2, whether the video is
> > captured
> > to or encoded to that format, frame accurate editing is not - and I
repeat
> > NOT possible. The program and the manufacturer that claims this frame
> > accurate editing is in short stretching the truth, and anyone who
believes
> > it is easily fooled.
> >
> > MPEG-2 when encoded, whether using VBR or CBR to a GOP with the IBBP
frame
> > structure has full frames only about 1/3 of the time. Every frame in
> > between
> > I frames is made up of information from subsequent and previous frames
in
> > the stream.
>
> ----From here to the next break is this poster demonstrating that -he-
> doesn't
> know how it can be done, therefore he can't accept that anyone else has
done
> it. I am sure there would be problems if the Frame Accurate MPEG Editors
> actually worked the way this poster seems to think that they
> do. ------------
>
> >These "so-called" frame accurate MPEG-2 editing packages may
> > have the ability to take the information from the BBP frames to create a
> > pseudo "full frame" but that is still NOT frame accurate. The only way
> > these
> > programs could come near to frame accurate editing would be to negate
the
> > BBP frames near the cut in favor of the nearest I frame.
> >
> > If this is not the case then the whole structure of the GOP would be
> > trashed
> > by the cut. The GOP cannot have a structure of IIBPIPBIPPI, which is
what
> > you get if true frame accurate editing is allowed. It's purely simple.
The
> > MPEG GOP standard is 15 and is divisable by 3. The explanation below
> > (which
> > is information from the Motion Pictures Engineers Group proper) shows
that
> > it is impossible to do frame accurate editing on MPEG files with the
IBBP
> > frame structure. ONLY I frame MPEG can be editing in frame accurate
mode.
>
> This may come as a shock, but the standard only sets the upper limit
> for GOP size (and current practice has extended that dramatically, check
out
> MPEG4 and there is an extended DVD (xDVD) that plays in most DVD
> players, See the TMPGEnc 3.0 XPress help files). All the cuts I've seen
> with VideoReDo result in two smaller GOP, each with a normal structure.
> By the way the PAL standard has the 15 frame per GOP limit with NTSC
> it's 18. There is no restriction, in the standards or in practice, to any
> smaller
> GOP all the way down to the I Frame only variety.
>
> Let Me speculate for a minute, you have never used VideoReDo or any
> other MPEG editor that "claims" to do frame accurate cuts; have you?
>
>
> ---- All the below is mostly quite accurate, if irrelevent. --------------
>
> > The GOP (Group of Pictures) Pattern is the arrangement of frames in an
> > MPEG
> > video stream. The GOP consists of a variable number of I, B, and P
frames.
> > There is not a standard way of formatting the groups, and different
> > manufacturers may choose quite varied GOP arrangement. One may use I, B,
> > and
> > P frames in specific groups arranged as IBBP, while another may use an
> > arrangement which incorporates on I and P frames, and others I-frames
> > only.
> >
> > The GOP interval and size will determine the pattern of the frame types
in
> > the MPEG stream. It is common practice to keep the number of pictures in
> > the
> > GOP at a number that is evenly divisible by the interval. So, if the
> > interval is 3 then the GOP has to be divisible by 3. MPEG has a standard
> > GOP
> > of 15 with the interval of 3.
> >
> > Using an IBBP arrangement will yield a low data rate video with the best
> > quality. When you use I-frames only the quality is much higher as is the
> > data rate also higher. When you want to keep bandwidth to a minimum and
> > maintain quality it is good to use the IBBP arrangement as the GOP.
> >
> ----------------------------
>
> If it were true that : "The program and the manufacturer that claims
> this frame accurate editing is in short stretching the truth, and anyone
who
> believes it is easily fooled." Then the fact that the MPEG that I cut
that
> way, starts or ends on the exact frame that I want, must be a really good
> illusion. If we are back to "it's not a REAL frame accurate cut" because
> it wasn't done your way, I give up.
>
> Luck;
> Ken
>
>
>
Anonymous
February 19, 2005 8:52:13 PM

Archived from groups: rec.video.desktop (More info?)

In article <m46Qd.110$lI2.79@bignews5.bellsouth.net>,
"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote:

> > > exactly the same to you and you can't tell the difference in
> pixelization
> > > between a 27" monitor and a 100" projection, then I have to question
> your
> > > ability to perceive video.
> > >
> > To make a Valid comparison the source Must be the same.
> > What I did and am now saying is that whatever differences there
> > are between the monitor and the projection, they don't change or
> > increase when I play one of my DVDs. The same differences
>
> As I said above, based on your posts in this thread I question your ability
> to perceive video artifacts that result from mpeg compression.


I think this whole thread is a nice reflection of the Blaise Pascal
comment that when the tool you have is a hammer, every problem starts to
look like a nail.

Both sides are struggling mightly to define the argument in terms of
what THEY experience and doing their damdest NOT to see it from the
other side.

Bad strategy, IMO.

Particularly if it's tied to the old stalking horse "I know how to look
at this clip and see things YOU can't see."

Don't get me wrong. I believe that statement is often 100% true. But I
also believe it's often 100% beside the point.

"Compromised" video formats have been winning the war decade after
decade - because what they provide, (portability, scalability, cost,
whatever) is often more important to the economics of the situation than
what they lack.

I know this is true because the last NLE users group meeting I attended
was chock full FULL of seasoned working pros trying to get a handle on
DV-based techniques.

Mostly guys who 5 years ago were sneering at DV as being too compressed
to be useful for anything other than "home video." Today are running
like demons to catch up with what they missed by dismissing it for too
long.

Hey, you bet SOMEONE is going to solve GOP editing. Or replace it with
something similar that lets lower budget players edit higher def signals.

The industry has learned that there's just too much money sitting around
below the "network professional" level to leave on the table.

My 2 cents anyway.
Anonymous
February 20, 2005 10:21:22 AM

Archived from groups: rec.video.desktop (More info?)

"William Davis" wrote ...
> Both sides are struggling mightly to define the argument
> in terms of what THEY experience and doing their damdest
> NOT to see it from the other side.
>
> Bad strategy, IMO.
>
> Particularly if it's tied to the old stalking horse "I know
> how to look at this clip and see things YOU can't see."
>
> Don't get me wrong. I believe that statement is often 100%
> true. But I also believe it's often 100% beside the point.
>
> "Compromised" video formats have been winning the war
> decade after decade - because what they provide, (portability,
> scalability, cost, whatever) is often more important to the
> economics of the situation than what they lack.

You seem to have bypassed the fact that the presenting question
came from one of the group of users for whom "editing" means
removing commercials from their off-air (or cable or satellite,
etc.) recording of South Park. Perhaps this whole genre of
activity (sorry, I can't bring myself to call it "editing") deserves
a new name and its own newsgroup.

It is a matter of producers vs. consumers. If you think that the
compressed formats will overtake the uncompressed formats
perhaps you aren't reading all the information available out
there. Check out, for example, the long-running thread on
"The HDV format...Compressed audio?"
Anonymous
February 20, 2005 8:24:06 PM

Archived from groups: rec.video.desktop (More info?)

>
> You seem to have bypassed the fact that the presenting question
> came from one of the group of users for whom "editing" means
> removing commercials from their off-air (or cable or satellite,
> etc.) recording of South Park.

Which, by any definition of the term IS editing. No, it's not the full
range of editing that you and I do - but it IS editing. Just as
switching a couple of paragraphs around in a personal letter or email is
as much "editing" as preparing a manuscript for publication in a
newspaper or magazine.

It's a matter of degree - NOT a different task, IMO.


Perhaps this whole genre of
> activity (sorry, I can't bring myself to call it "editing") deserves
> a new name and its own newsgroup.

If things evolve that way fine, but don't hold your breath - It's like
asking that there be a separate term for BASEBALL when it's done by pros
rather than amatures. It's just baseball - the same way this is all
"editing". You want to say "pro editing" like we distinguish "pro
baseball" fine.

>
> It is a matter of producers vs. consumers. If you think that the
> compressed formats will overtake the uncompressed formats
> perhaps you aren't reading all the information available out
> there. Check out, for example, the long-running thread on
> "The HDV format...Compressed audio?"

Hello? the compressed formats LONG AGO took over from "uncompressed"
ones.

There's a lot more DV and DVCAM being shot out there than Digibeta.
Simple economies.

And as to the HDV thread - the discussion - in large part among working
audio pros - is about how to WORK WITH the new format. Judging it's
audio capabilities rationally.

I'm sure there are compromises involved in both the video and the audio
streams in HDV - but if clients want to work with them - the ONLY thing
we can do as professional videomakers is to learn about them so that we
can make good recommendations as to when it's appropriate to dive out to
double system or when it's okay to track our audio to on-board tape.

A case by case judgement based on what the client expects.

Like it's always been.
Anonymous
February 20, 2005 11:24:47 PM

Archived from groups: rec.video.desktop (More info?)

This is from an article in Broadcast Engineering by Michael Robin:

"Seamless frame-accurate editing of compressed video is most easily
accomplished with the use of short and closed GOP structures. A closed
GOP does not contain frames that make reference to frames in the
preceding GOP. Longer GOP structures can be edited by decoding and
re-encoding or by transcoding to shorter GOP structures."

Complete article:

http://artistoftheyear.broadcastengineering.com/ar/broa...
Anonymous
February 21, 2005 10:38:08 AM

Archived from groups: rec.video.desktop (More info?)

"Mark Burns" <marcus520520@yahoo.com> wrote in message
news:1108959887.771834.67430@g14g2000cwa.googlegroups.com...
> This is from an article in Broadcast Engineering by Michael Robin:
>
> "Seamless frame-accurate editing of compressed video is most easily
> accomplished with the use of short and closed GOP structures. A closed
> GOP does not contain frames that make reference to frames in the
> preceding GOP. Longer GOP structures can be edited by decoding and
> re-encoding or by transcoding to shorter GOP structures."
>
> Complete article:
>
> http://artistoftheyear.broadcastengineering.com/ar/broa...
>

From your post:

"Longer GOP structures can be edited by decoding and
re-encoding or by transcoding to shorter GOP structures."

Which is what I've been saying from the beginning.
Anonymous
February 21, 2005 11:15:25 PM

Archived from groups: rec.video.desktop (More info?)

"William Davis" <newvideo@fastq.com> wrote in message
news:newvideo-47A7B8.17521319022005@news.west.cox.net...
> In article <m46Qd.110$lI2.79@bignews5.bellsouth.net>,
> "Chuck U. Farley" <chuckufarley@dyslexia.com> wrote:

> Hey, you bet SOMEONE is going to solve GOP editing. Or replace it with
> something similar that lets lower budget players edit higher def signals.
>
> The industry has learned that there's just too much money sitting around
> below the "network professional" level to leave on the table.
>
> My 2 cents anyway.


If you look at the MPEG spec you will see that GOP editing is an
interruption in the transcode format. So unless you have complete control
over the transcoding initally you will suffer quality differences between
edits.

Not to mention the fact that an MPEG stream is already compressed and in a
GOP there is usually only a single frame which represents the 'key'' so you
hvae to reconstruct the intermediate frames fromm the delta data that
follows. Then you have to recompress it.

Not exactly an editable format. But because of this MPEG editing will always
be clumsy.
Anonymous
February 21, 2005 11:18:33 PM

Archived from groups: rec.video.desktop (More info?)

"PTRAVEL" <ptravel@ruyitang.com> wrote in message
news:AdgSd.2323$OU1.1055@newssvr21.news.prodigy.com...
>
> "Mark Burns" <marcus520520@yahoo.com> wrote in message
> news:1108959887.771834.67430@g14g2000cwa.googlegroups.com...
>> This is from an article in Broadcast Engineering by Michael Robin:
>>
>> "Seamless frame-accurate editing of compressed video is most easily
>> accomplished with the use of short and closed GOP structures. A closed
>> GOP does not contain frames that make reference to frames in the
>> preceding GOP. Longer GOP structures can be edited by decoding and
>> re-encoding or by transcoding to shorter GOP structures."
>>
>> Complete article:
>>
>> http://artistoftheyear.broadcastengineering.com/ar/broa...
>>
>
> From your post:
>
> "Longer GOP structures can be edited by decoding and
> re-encoding or by transcoding to shorter GOP structures."
>
> Which is what I've been saying from the beginning.
>

EXACTLY! Even with a closed GOP, which is really what DV is since each
frame stands alone and is not dependent on previous frames, you still have
the problem of the other frames int he group having to be recontructed and
then recompressed. But the closed GOP is the best way to deal with an
otherwise uneditable format.

>
>
Anonymous
February 22, 2005 1:15:04 AM

Archived from groups: rec.video.desktop (More info?)

"nap" <gospam@yourself.com> wrote in message
news:tmrSd.2456$OU1.2270@newssvr21.news.prodigy.com...
>
> "PTRAVEL" <ptravel@ruyitang.com> wrote in message
> news:AdgSd.2323$OU1.1055@newssvr21.news.prodigy.com...
>>
>> "Mark Burns" <marcus520520@yahoo.com> wrote in message
>> news:1108959887.771834.67430@g14g2000cwa.googlegroups.com...
>>> This is from an article in Broadcast Engineering by Michael Robin:
>>>
>>> "Seamless frame-accurate editing of compressed video is most easily
>>> accomplished with the use of short and closed GOP structures. A closed
>>> GOP does not contain frames that make reference to frames in the
>>> preceding GOP. Longer GOP structures can be edited by decoding and
>>> re-encoding or by transcoding to shorter GOP structures."
>>>
>>> Complete article:
>>>
>>> http://artistoftheyear.broadcastengineering.com/ar/broa...
>>>
>>
>> From your post:
>>
>> "Longer GOP structures can be edited by decoding and
>> re-encoding or by transcoding to shorter GOP structures."
>>
>> Which is what I've been saying from the beginning.
>>
>
> EXACTLY! Even with a closed GOP, which is really what DV is since each
> frame stands alone and is not dependent on previous frames, you still have
> the problem of the other frames int he group having to be recontructed and
> then recompressed. But the closed GOP is the best way to deal with an
> otherwise uneditable format.

I don't expect the OTA compilers to get it, but at least we tried. ;) 

On a related topic, I've been looking at Sony's new HD handycam, which uses
a 25-meg mpeg stream. As I recall, Sony has worked with Adobe to create a
plugin for Premiere that will allow editing the Sony HD format. Do you know
how they're doing it? The high bit rate would certainly help, but I still
don't see any way around re-transcoding.


>
>>
>>
>
>
Anonymous
February 22, 2005 12:56:24 PM

Archived from groups: rec.video.desktop (More info?)

> thread going was an inquiry about going from AVI to DVD. One poster
> recommended capturing in mpeg rather than AVI, editing the mpeg in
VideoReDo

I've found those who recommend mpeg capture invariably use Hauppage video
cards. They have no other choice as they _have_ to capture in mpeg as the
cards won't allow avi capture.


> shown on, it works fine. The problem, which, among other things resulted
in
> this subthread, is that the poster claimed the quality was
indistinguishable
> from video produced by editing AVI in a proper NLE, transcoding it to mpeg
> using 2-pass VBR (and sizing it correctly at that point) and then
authoring
> to DVD. He wasn't only wrong, he was arrogant about (and quite
insulting).

I have had "discussions" with the poster in question in many threads,
including this one. He seems to have a fanatical belief in VideoReDo. While
it may be a nice piece of s/w for mpeg editing, it's certainly not the only
one available and I learned a very long time ago that there is no "best" s/w
for _any_ application.

> And don't worry -- though I do represent content producers, HBO isn't a
> client (and who's Glen Frey?). ;)  The fair use question is an interesting

I thought he was the writer for New York Minute but I was wrong, it's Glen
Frey. Both were/are in the Eagles.

> one -- I don't think, under this Supreme Court (and with district court
> judges constituting, primarily, Reagan and Bush appointees) that Survivor
> compilations, or even my transfers from Tivo to my laptop, could clearly
be
> said to come within fair use. It's a pity, too.

As I said on the website on Nov. 3, the American people are going to get
exactly what they deserve.
Anonymous
February 22, 2005 12:56:25 PM

Archived from groups: rec.video.desktop (More info?)

"Chuck U. Farley" <chuckufarley@dyslexia.com> wrote in message
news:lFHSd.14225$hd6.12022@bignews1.bellsouth.net...
> > thread going was an inquiry about going from AVI to DVD. One poster
> > recommended capturing in mpeg rather than AVI, editing the mpeg in
> VideoReDo
>
> I've found those who recommend mpeg capture invariably use Hauppage video
> cards. They have no other choice as they _have_ to capture in mpeg as the
> cards won't allow avi capture.

Ah, the old "when your only tool is a hammer, the world look like it is full
of nails" problem.

>
>
> > shown on, it works fine. The problem, which, among other things
resulted
> in
> > this subthread, is that the poster claimed the quality was
> indistinguishable
> > from video produced by editing AVI in a proper NLE, transcoding it to
mpeg
> > using 2-pass VBR (and sizing it correctly at that point) and then
> authoring
> > to DVD. He wasn't only wrong, he was arrogant about (and quite
> insulting).
>
> I have had "discussions" with the poster in question in many threads,
> including this one. He seems to have a fanatical belief in VideoReDo.
While
> it may be a nice piece of s/w for mpeg editing, it's certainly not the
only
> one available and I learned a very long time ago that there is no "best"
s/w
> for _any_ application.

I also disagree with his reference to VideoReDo as an NLE. Yes, it's an
editor in the sense that it can do cuts. However, it doesn't begin to
approach the functionality of(or serve as a replacement for) even the most
basic, entry level NLE, e.g. MovieMaker, iMovie, etc.

Again, VideoReDo may be the tool of choice for OTA compilers (I've looked at
it, and it's okay for that purpose, but just okay), but it's not even
remotely adequate for handling a child's birthday party video, much less
anything more elaborate.

>
> > And don't worry -- though I do represent content producers, HBO isn't a
> > client (and who's Glen Frey?). ;)  The fair use question is an
interesting
>
> I thought he was the writer for New York Minute but I was wrong, it's Glen
> Frey. Both were/are in the Eagles.
>
> > one -- I don't think, under this Supreme Court (and with district court
> > judges constituting, primarily, Reagan and Bush appointees) that
Survivor
> > compilations, or even my transfers from Tivo to my laptop, could clearly
> be
> > said to come within fair use. It's a pity, too.
>
> As I said on the website on Nov. 3, the American people are going to get
> exactly what they deserve.

Yep -- we're going to reap the whirlwind, no question about it. I better
dust off my copy of The Handmaid's Tale and study up. ;) 

>
>
Anonymous
February 23, 2005 12:50:08 PM

Archived from groups: rec.video.desktop (More info?)

> Yep -- we're going to reap the whirlwind, no question about it. I better
> dust off my copy of The Handmaid's Tale and study up. ;) 

Nice reference! Not many people familiar with that title, at least in my
circles. For me it's a more obvious reference. Winston Smith immediately
comes to mind, just 20-25 years later than Orwell predicted. <vbg>
!