H.264 Bit rates above 3X possible?

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Agent86

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Aug 22, 2011, 7:02:23 AM8/22/11
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So it seems quite easy to record video at CBR x1.7-x2 with a
sufficiently fast SDHC card, such as a Sandisk Extreme. However
anything beyond x2 CBR results in the buffer filling up & then the
record process aborts.

I have noticed that as soon as I disable audio in the main menu, I'm
able to record CBR x3 for as long as I like.
As audio takes up very little space, (comparatively to video), it
seems it's more the overhead of the camera trying to process both
audio & video is causing the issues, rather than the data rate being
pushed too high.

I'd be interested to know how far we can push the h.264 data rate,
(without audio), before we hit the max of the buffer or SDHC write
speed. Would it be possible to request a modification to the CBR that
would allow x4,x5 & x6 to experiment with?



Alex

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Aug 22, 2011, 7:09:04 AM8/22/11
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There's no point in pushing CBR above x3, since QScale clamps at -16
(and bitrate won't increase further). I'll actually remove all
settings higher than x2 from the menu (they are dangerous, it will
stop recording as soon as it will encounter sufficient detail).

What can be done to increase data rate is to try to increase the file
write buffer. But that's difficult (it will require a lot of reverse
engineering for movie functions, and there's no guarantee of success).

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Agent86

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Aug 22, 2011, 7:49:23 AM8/22/11
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Increasing the file write buffer sounds like a lot of work. With HDMI
recorders becoming increasingly affordable, (Atomos Ninja, BMD
shuttle), it seems like the more realistic way to go.

My next question would be, is it possible to implement a continually
clean HDMI out, (i.e. no overlays), whilst still retaining overlay
information on the camera LCD?

Lastly, the HDMI output is always locked at 29.97, (whether NTSC or
PAL setup). The 24P or 25P progressive frames are embedded within this
stream, this is why even when using a Ninja recorder you must "strip
away" or "pull down" the redundant frames. Is there any chance of a
true progressive output, 24P or 25P, from HDMI?

Alex

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Aug 22, 2011, 7:51:11 AM8/22/11
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No, and no.

jraiber

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Aug 22, 2011, 3:01:22 PM8/22/11
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boah, thats great, i made a quick test and was very surprised. indeed
with sound disabled, the datarate arround 100Mbit is easily
recordable. (with audio on, it stops at around 70) I was looking for
increasing the datatrate that much for a long time!
hmm, but i need one audiotrack to record timecode, but i would need
only one first second of audio to set the timecode for the clip. But i
ditn't come into the main menu to switch of the sound, while
recording.
Hmm, now i have to decide: weeks of work to synchronize manually but
with very less compression, or the opposite.
Or have anyone out there a different idea?
I'm happy about this news.

greets,
Jan

Ivo Silva

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Aug 22, 2011, 3:14:02 PM8/22/11
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Jan, can't you just use a clapper, then synchronize with markers on
Premiere/Final Cut?

jraiber

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Aug 23, 2011, 4:20:46 AM8/23/11
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Yes, i thought about it. but i'm a one-man-show, so it's hard to clap,
especially for documentary...

Ivo Silva

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Aug 23, 2011, 6:21:18 AM8/23/11
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I've read on another thread that ML can make the camera beep. Maybe
you can request that someone makes an option to make it beep when it
starts recording. Maybe it would be picked up by your sound recorder,
and you could sync with it.

nanomad

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Aug 23, 2011, 7:22:06 AM8/23/11
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On Tue, Aug 23, 2011 at 10:20, jraiber <jra...@web.de> wrote:
> Yes, i thought about it. but i'm a one-man-show, so it's hard to clap,
> especially for documentary...

You can always scream, a high enough noise should do the trick

Ivo Silva

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Aug 23, 2011, 7:31:37 AM8/23/11
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Nanomad, but then how would he sync it?

James Donnelly

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Aug 23, 2011, 7:35:23 AM8/23/11
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Have you looked at Pluraleyes?  It does the syncing pretty much for you and gets rave reviews.  I have not tried it.

http://www.singularsoftware.com/pluraleyes.html

Ivo Silva

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Aug 23, 2011, 7:50:46 AM8/23/11
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James and Nanomad:

I think that the point here is NOT to record audio through the camera
in the first place, so we can achieve higher bitrates with video
alone.

How can you sync it then?

My first suggestion was the a clapper, but as jraiber stated, he's a
one-man-show, and it's just inconvenient to use a clapper when
shooting documentary. So I sugested the in-camera beep. The reasoning
is simple: If he knows the camera beeps at frame 1 of the video, and
he ears the recorded beep on the external audio recorder, then he can
sync that point in the audio to the first frame in the video, without
the need for timecodes or clappers, or sound embeded in the video
file.

Alex

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Aug 23, 2011, 7:53:38 AM8/23/11
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Is the beep loud enough? Can it be played while recording? (use "don't
click me" for testing)

(all my batteries are empty right now, so I can't test)

Ivo Silva

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Aug 23, 2011, 8:15:38 AM8/23/11
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Just did a quick test on my 600D, and I think it could work.

This are the steps I took:

- Pressed "Rec", activated ML menu, used "don't click me" and when it
beeps the camera stops recording. When I play the video, I can ear the
audio cutting of when I press the button, and for that last second
there's no audio at all.

If I deactivate the audio recording in the Canon Menu, I can reach the
ML menu and activate the beep and the camera doesn't stop recording.
It's not too loud but I think that It can be picked up by an external
recorder (wich I don't have, so I can't test right now) if it's close
to the body.

Anyway, I feel that this could become an option ("Beep When Recording
Starts - Warning, audio must be disabled").

Alex

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Aug 23, 2011, 8:30:59 AM8/23/11
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Try with this autoexec (not tested). If it's good for sync purposes...
I'll have to find a place for this in the menu :)

Here's the extra code:

PROP_HANDLER(PROP_MVR_REC_START)
{
if (buf[0] == 2) Beep();
return prop_cleanup( token, property );

autoexec.bin

James Donnelly

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Aug 23, 2011, 8:39:47 AM8/23/11
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Ivo,

I think you may have mis-understood or not read the info on the link.  I understand well that we are talking about dual system sound to maximise the video data rate.  Pluraleyes is designed to automatically sync audio with video without the need for a clapper, or a beep for that matter.

I think the beep is a great idea to be a replacement for the clapper, but the question raised was is there an alternative to 'weeks of work' manually syncing.  Pluraleyes offers such an alternative, whereas the beep does not.  It just replaces the clapper.

Ivo Silva

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Aug 23, 2011, 8:39:33 AM8/23/11
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Thanks Alex,

Was just heading to lunch, will try when I get back.

Once again, thanks!

Alex

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Aug 23, 2011, 8:42:24 AM8/23/11
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> Pluraleyes is designed to automatically sync audio with
> video without the need for a clapper, or a beep for that matter.

Wow, I'll need this program too, but they don't seem to have a
standalone version. Will research it a bit.

Ivo Silva

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Aug 23, 2011, 9:31:29 AM8/23/11
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James,

I'm sorry if I'm wrong. I just don't understand how you can sync a
video file without any audio information, with an audio file without
timecode/clapper or any other reference. I know how to do it "by
hand", but I can't understand how a software does it. Could you
briefly explain it? From what I understood from the site you linked,
the software "replaces" the audio stream from the video (if there is
one to begin with) with an external audio file, by searching similar
patterns. Again, I repeat that what we're trying to achieve here is to
record video without sound, and sync it with an external audio source.
Usually that's what a clapper is for, so I suggested the beep to those
who can't use one.

This is a direct quote from the site (describing DualEyes, the
standalone version):

"The preferred solution is dual-system audio: capture sound on a
separate recorder and substitute this for the camera audio in
post-production.
DualEyes™ makes this complicated process a snap. It uses the same
underlying technology as its big brother, PluralEyes®, to
automatically sync and cut the audio recording into clips that match
the video clips."

Alex, as I said in the above text, there's a standalone version called DualEyes.

Again, sorry if I'm wrong. Maybe we're just talking about different things.

Ivo Silva

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Aug 23, 2011, 9:42:19 AM8/23/11
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@Alex,

The bin with the beep doesn't work. When I press "Rec" the shutter
activates, and it flashes on screen the "Error 70 - Can't start
recording while shutter being used" (or something to that extent).

Alex

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Aug 23, 2011, 9:46:09 AM8/23/11
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Well... out of luck.

Ivo Silva

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Aug 23, 2011, 9:49:51 AM8/23/11
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No problem, thanks anyway =) I'm loving ML more and more each day!

James Donnelly

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Aug 23, 2011, 10:04:08 AM8/23/11
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Bad news all round.  It was me who didn't understand Pluraleyes:

"Can PluralEyes sync cameras that have no audio track at all?

No, PluralEyes needs audio to sync. It does not look at the video tracks at all."

Seems obvious now.  I did wonder how it could sync without a reference, but then I drifted into another day dream.

So in short, it seems the solution viability matrix is something like this:

Beeping: no

Screaming: no

Pluraleyes / Dualeyes: no

Timecode: no (would need to record SMTE into the audio track, defeating the object)

Clapping/clappering: yes


The only other thing I can think of that might help is if we had some way of simultaneously triggering the start/stop recording controls on both the audio and the video recorder, which seems unlikely to be completely accurate or easy to do.

Malcolm Debono

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Aug 23, 2011, 10:08:20 AM8/23/11
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On Tuesday, August 23, 2011 4:04:08 PM UTC+2, James wrote:

The only other thing I can think of that might help is if we had some way of simultaneously triggering the start/stop recording controls on both the audio and the video recorder, which seems unlikely to be completely accurate or easy to do.

 That seems to be the best way. However it doesn't have to be accurate as long as the delay between pressing both buttons is constant, since you can easily fix that in post by moving the audio track forward/backward according to the delay.

Ivo Silva

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Aug 23, 2011, 10:10:40 AM8/23/11
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The other solution would be to decrease the quality of the audio
recording in-camera, making room for an higher quality video, and then
we'd have reference to work with PluralEyes/DualEyes. I just don't
know if that's possible at all.

scrax

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Aug 23, 2011, 10:13:51 AM8/23/11
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I'm not a videomaker, I use ML for photos at first, but I was thinking if a one man clapper can't be made with a little plastic like a ruler "gently" slapped on the lens hood?

Message has been deleted

Malcolm Debono

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Aug 23, 2011, 10:16:10 AM8/23/11
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Is it possible to start a recording with audio enabled and then turn it off after a few seconds while still recording video? This would give us a small audio clip which we can then use with Pluraleyes to sync with the external recording.

scrax

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Aug 23, 2011, 10:24:18 AM8/23/11
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Nice idea, but it also need to change the bitrate during rec after disabling audio...

Alex

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Aug 23, 2011, 10:29:23 AM8/23/11
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Audio is uncompressed as far as I know, and I don't think it's
possible to change it in the middle of recording. There are several
initializations related to audio setting in mvrRecStart.

On Tue, Aug 23, 2011 at 5:24 PM, scrax <scr...@gmail.com> wrote:
> Nice idea, but it also need to change the bitrate during rec after disabling
> audio...
>

James Donnelly

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Aug 23, 2011, 10:52:07 AM8/23/11
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You need to clearly see within a couple of video frames where the audio spike corresponds, and I'm not sure a ruler slapping the lens hood would do that. 

You got me thinking though.  It seems that a convenient one handed clapper is required.  Eureka! Barbeque tongs!  Simply tie a pair to your rig with some garden twine for handy access.

Obviously, it will be hard to explain to people on set who naturally find questions arising from your actions.  You could explain that you are merely catching flies that might otherwise interfere with the shot.

But seriously, there is an app for that, of course:

http://itunes.apple.com/us/app/id320315888?mt=8

http://www.androidfreeware.net/download-clapperboard.html

On 23 August 2011 15:13, scrax <scr...@gmail.com> wrote:
I'm not a videomaker, I use ML for photos at first, but I was thinking if a one man clapper can't be made with a little plastic like a ruler "gently" slapped on the lens hood?

Ivo Silva

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Aug 23, 2011, 10:55:52 AM8/23/11
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An App! Of course! Boy, do I feel stupid! One more reason to get a
tablet ehehe =)

jraiber

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Aug 23, 2011, 4:49:34 PM8/23/11
to Magic Lantern firmware development
Hi guys, it's very cool, that you brainstorm for my situation. I thank
you very much.
But I think, i should explain better my way of filming, which i worked
out for a long time.
On top of my shoulder i've my 60d attached with a shotgun mic, and one
for my voice, asking the questions to my protagonists.
But this mics and a wireless receiver are connected to a multitrack-
audio-recorder (mostly i get a tascam dr-680) not to the 60d.
To sync audio and video i'v generated a 24h-long smtp audio-file as
mp3, which plays, yes, an ordinary mp3-player (instead of super
expensive tc-gens) and feed into one audio-track of the tascam and one
of the 60d.
The audio-recorder runs constantly while i'm filming a scene or a
discussion, sometimes one or two hours. Audio is "cheap" and so i do
not miss any beginning or ending of a sentence, if i'm to slow with
switching on, or to fast with switching off the video.
Than in post, reading audio-timecode and syncing both is done with a
snap of my fingers, yeah!


And now, it's a bit like a new challenge, to make this possible with
disabled sound on the 60d.

Pluraleyes works only with audio on the video, comparing it with audio
on the multitracker.

The beeb is a good idea, years ago i built a little handy box with a
flashing led sametime with a very short beep. But there are two
reasons for not beeping around. First is, people become sometimes
confused (or know, ah, now you're recording...) and second is, I made
my audio unusable, otherwise i had to beep at a break between two
words.... it was terrible.

So beeping is only useful, if it comes out of a connector, maybe the
miniusb-port of the cam, not out of a speaker.

Now you know, why i'm looking for a solution, which keeps my
development of the timecode-workflow.
I thought, would a single mono audio-track work similar to the normal
stereo mode? Or a compressed one work different? I don't know really,
but i think it has to to with writing two separate streams (audio and
video) to the card at the same time, jumping back and forward
constantly, which brings the bottleneck so close. So a mono-mode would
not solve it, i guess.

My observations of the video-data-rate has shown me, that the rate
rises up from a very low level to its average in the time of some
seconds after you push record. So theoretically there would be space
to record one ore two seconds of audio and than switch it of. But i
have no idea, if it's possible to do so while recording.

In post it's no problem, i think every timecode-reading application
can count up the numbers for the rest of the clip.

An other option, reading the incoming timecode and setting it in the
header of the .mov file (which is called a timecode-track) is what i
would call a daydream...
=)

So long, thanks again for your proposals,
greets,
Jan



On 23 Aug., 16:04, James Donnelly <jamesjdonne...@gmail.com> wrote:
> Bad news all round.  It was me who didn't understand Pluraleyes:
>
> "Can PluralEyes sync cameras that have no audio track at all?
>
> No, PluralEyes needs audio to sync. It does not look at the video tracks at
> all."
>
> Seems obvious now.  I did wonder how it could sync without a reference, but
> then I drifted into another day dream.
>
> So in short, it seems the solution viability matrix is something like this:
>
> Beeping: no
>
> Screaming: no
>
> Pluraleyes / Dualeyes: no
>
> Timecode: no (would need to record SMTE into the audio track, defeating the
> object)
>
> Clapping/clappering: yes
>
> The only other thing I can think of that might help is if we had some way of
> simultaneously triggering the start/stop recording controls on both the
> audio and the video recorder, which seems unlikely to be completely accurate
> or easy to do.
>
> On 23 August 2011 14:49, Ivo Silva <ivo.silva.lei...@gmail.com> wrote:
>
>
>
> > No problem, thanks anyway =) I'm loving ML more and more each day!
>
> > On Tue, Aug 23, 2011 at 14:46, Alex <broscutama...@gmail.com> wrote:
> > > Well... out of luck.
>
> > > On Tue, Aug 23, 2011 at 4:42 PM, Ivo Silva <ivo.silva.lei...@gmail.com>
> > wrote:
> > >> @Alex,
>
> > >> The bin with the beep doesn't work. When I press "Rec" the shutter
> > >> activates, and it flashes on screen the "Error 70 - Can't start
> > >> recording while shutter being used" (or something to that extent).
>
> > >> On Tue, Aug 23, 2011 at 14:31, Ivo Silva <ivo.silva.lei...@gmail.com>
> > >>> On Tue, Aug 23, 2011 at 13:42, Alex <broscutama...@gmail.com> wrote:
> > >>>>> Pluraleyes is designed to automatically sync audio with
> > >>>>> video without the need for a clapper, or a beep for that matter.
>
> > >>>> Wow, I'll need this program too, but they don't seem to have a
> > >>>> standalone version. Will research it a bit.
>
> > >>>> On Tue, Aug 23, 2011 at 3:39 PM, James Donnelly
> > >>>> <jamesjdonne...@gmail.com> wrote:
> > >>>>> Ivo,
>
> > >>>>> I think you may have mis-understood or not read the info on the
> > link.  I
> > >>>>> understand well that we are talking about dual system sound to
> > maximise the
> > >>>>> video data rate.  Pluraleyes is designed to automatically sync audio
> > with
> > >>>>> video without the need for a clapper, or a beep for that matter.
>
> > >>>>> I think the beep is a great idea to be a replacement for the clapper,
> > but
> > >>>>> the question raised was is there an alternative to 'weeks of work'
> > manually
> > >>>>> syncing.  Pluraleyes offers such an alternative, whereas the beep
> > does not.
> > >>>>> It just replaces the clapper.
>
> > >>>>> On 23 August 2011 12:50, Ivo Silva <ivo.silva.lei...@gmail.com>
> > wrote:
>
> > >>>>>> James and Nanomad:
>
> > >>>>>> I think that the point here is NOT to record audio through the
> > camera
> > >>>>>> in the first place, so we can achieve higher bitrates with video
> > >>>>>> alone.
>
> > >>>>>> How can you sync it then?
>
> > >>>>>> My first suggestion was the a clapper, but as jraiber stated, he's a
> > >>>>>> one-man-show, and it's just inconvenient to use a clapper when
> > >>>>>> shooting documentary. So I sugested the in-camera beep. The
> > reasoning
> > >>>>>> is simple: If he knows the camera beeps at frame 1 of the video, and
> > >>>>>> he ears the recorded beep on the external audio recorder, then he
> > can
> > >>>>>> sync that point in the audio to the first frame in the video,
> > without
> > >>>>>> the need for timecodes or clappers, or sound embeded in the video
> > >>>>>> file.
>
> > >>>>>> On Tue, Aug 23, 2011 at 12:35, James Donnelly <
> > jamesjdonne...@gmail.com>
> > >>>>>> wrote:
> > >>>>>> > Have you looked at Pluraleyes?  It does the syncing pretty much
> > for you
> > >>>>>> > and
> > >>>>>> > gets rave reviews.  I have not tried it.
>
> > >>>>>> >http://www.singularsoftware.com/pluraleyes.html
>
> > >>>>>> > On 23 August 2011 12:31, Ivo Silva <ivo.silva.lei...@gmail.com>
> > wrote:
>
> > >>>>>> >> Nanomad, but then how would he sync it?
>
> > >>>>>> >> On Tue, Aug 23, 2011 at 12:22, nanomad <condel...@gmail.com>
> > wrote:

daniel thissen

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Aug 23, 2011, 6:03:43 PM8/23/11
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activa audio remoteshot on,level 10
desactiva el audio desde el menu de canon
envia la señal de tu mixer a tu camara
pon rec en tu  grabadora externa y cuando quieras que la camara arranque a grabar mandas la señal  de tono 1000 ciclos.
luego sincronizas  el comienzo del video  con el comienso del tono.
sincronia perfecta  sin grabar audio en camara . :)

active remoteshot on, level 10
* disable the audio from canon 
menu
* sends the signal from your mixer to your 
camera
* pres REC in your external recorder and when you want the camera to start 
recording send the tone signal  1000Hz
* 
sync video whit 1000Hz
perfect synchrony without recording audio on camera. :)
 

2011/8/23 jraiber <jra...@web.de>

jraiber

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Aug 24, 2011, 10:17:11 AM8/24/11
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ok, could work, so i have an additional audio-track on the recorder,
which have the tone switched on, at the moment where the camera was
switched to record. it's a lot to do in post, to sync hundreds of
clips to this peaks, but it's more than nothing. i'll think about it,
if the work is worth.
But thank you for your idea. I'll try, how fast i'll be, to do so.
all the best and greets,
jan



On 24 Aug., 00:03, daniel thissen <thissendan...@gmail.com> wrote:
> activa audio remoteshot on,level 10
> desactiva el audio desde el menu de canon
> envia la señal de tu mixer a tu camara
> pon rec en tu  grabadora externa y cuando quieras que la camara arranque a
> grabar mandas la señal  de tono 1000 ciclos.
> luego sincronizas  el comienzo del video  con el comienso del tono.
> sincronia perfecta  sin grabar audio en camara . :)
>
> * active remoteshot on, level 10
> * disable the audio from canon menu
> * sends the signal from your mixer to your camera
> * pres REC in your external recorder and when you want the camera to
> start recording
> send the tone signal  1000Hz
> * sync video whit 1000Hz
> perfect synchrony without recording audio on camera. :)
>
> 2011/8/23 jraiber <jrai...@web.de>
> > > > >>>>>> >> > You can always scream, a...
>
> Erfahren Sie mehr »

Alex

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Aug 24, 2011, 10:22:20 AM8/24/11
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I might be able to make the flash pop up at some point (when starting
recording). Would that help?

daniel thissen

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Aug 24, 2011, 10:24:55 AM8/24/11
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solo necesitas mandar el tono por un instante, eso activara el rec en camara .
no requieres un canal mas en la grabadora.
para sincronizar solo tienes que poner el principio del video con el pico del tono .
ojala te ayude , yo lo probe y funciona bien. 

google traslate

just send the tone for a moment, that activate the rec on ​​camera.
you do not need another channel on the recorder.
to synchronize only have to place the beginning of the video with the peak of the tone.
hopefully help you, I tried it and works well.


2011/8/24 jraiber <jra...@web.de>

--

Alex

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Aug 24, 2011, 10:30:56 AM8/24/11
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> solo necesitas mandar el tono por un instante, eso activara el rec en camara

Nice tip, I'll add it to the user guide, gracias :)

jraiber

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Aug 24, 2011, 2:02:30 PM8/24/11
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Ok,i got, that i should use the audio remote shot to start the cam.
But i ditn't get what do you mean with "you do not need another
channel on the recorder"? Maybe i'm to slow today, but i have to sync
to some point in the audio, right?

I would try this, but together with a switch, i'm using to start-stop
the cam. (remote-In, record-button=half-shutter) the switch simply
close a circuit, so i could use a double-one which can close
additional a tone circuit and record this to an extra channel of the
audio-recorder. Than i should have an audio-track with beeps, which i
can sync to.
Than i think, the beepsnyc should be only a fine-tune. The main
sorting and placing of the clips next to sync-points should work with
creation date. I hope so.
Much easier would be, the cam itself sends a beep on audio-out, if it
records. Or even better than a beep, a constant tone until stop.

The flash-popuop would drive me crazy, i'm shure. =)

but never the less, thanks again,
cheers,
jan



On 24 Aug., 16:24, daniel thissen <thissendan...@gmail.com> wrote:
> solo necesitas mandar el tono por un instante, eso activara el rec en camara
> .
> no requieres un canal mas en la grabadora.
> para sincronizar solo tienes que poner el principio del video con el pico
> del tono .
> ojala te ayude , yo lo probe y funciona bien.
>
> google traslate
>
> just send the tone for a moment, that activate the rec on ​​camera.
> you do not need another channel on the recorder.
> to synchronize only have to place the beginning of the video with the peak of
> the tone.
> hopefully help you, I tried it and works well.
>
> 2011/8/24 jraiber <jrai...@web.de>
>
>

Alex

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Aug 24, 2011, 2:06:25 PM8/24/11
to ml-d...@googlegroups.com
> Much easier would be, the cam itself sends a beep on audio-out, if it
> records. Or even better than a beep, a constant tone until stop.

When I toggle Mic Power from menu, and I connect headphones instead of
a microphone, I hear a pretty solid clicking sound.

So, you can consider the 3.5 mic jack as "audio out", and I can make
that click from magic lantern when starting recording (or so).

Please test it from ML menu first (just to see if your recorder
detects the click).

daniel thissen

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Aug 24, 2011, 2:27:11 PM8/24/11
to ml-d...@googlegroups.com
Hola Alex
yo detecto perfectamente el clik en mi  mixer , no tengo la grabadora  en casa. No puedo grabarlo.
Gracias por ML es  simplemente inbreible!!


google translate

I detect clik perfectly in my mixer, I don't have the recorder at home. I can not record it.

Jan:
but i have to sync
to some point in the audio, right?

En tu archivo de audio vas a tener  un pico  en el instante en el que presionaste el boton del tono, ese pico lo sincronizas con el comienzo del archivo de video y van a correr perfectamente en sincro.
ojala te ayude en algo. 

google translate
your Audio file is  going to have a peak at the instant the  tone button is pressed , this peak is synchronized to the beginning of the video file and will run perfectly in sync.
hopefully help you with something.


2011/8/24 Alex <broscu...@gmail.com>

daniel thissen

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Aug 24, 2011, 2:30:24 PM8/24/11
to ml-d...@googlegroups.com
PD: tienes que  poner a grabar el audio antes del tono.
Googel T:
PS: you have to star recording  the audio before the tone.

2011/8/24 daniel thissen <thisse...@gmail.com>

jraiber

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Aug 24, 2011, 3:21:34 PM8/24/11
to Magic Lantern firmware development
cool idea, i'll try tomorrow.
thanks a lot.
jan

lightimages

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Aug 25, 2011, 12:42:29 PM8/25/11
to Magic Lantern firmware development
Hi Alex

Another simple fix for cam/ext audio sync mark.

Start camera. Start audio recorder.

Hold an external flash unit, pointed up, near the mic for the recorder
and press the test button on the flash. Dumping the flash capacitor
makes a very audible pop that's easy to pickup on a nearby mic.

White frame of video matches POP on mic recorder +/- a frame. The
frame offset will be constant if the flash is always the same distance
from the audio recorder.

I use this trick to sync video cameras and HDSLR's on multi-cam
shoots. It really helps in spots where PluralEyes gets lost.

Sub-tip: Mount the flash on the recorder stand, if you are using one.
Even add a remote flash trigger at the camera.

BTW - The new release is working great on my T2i. Terrific work.

George
Light Images

jraiber

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Aug 30, 2011, 2:03:15 PM8/30/11
to Magic Lantern firmware development
Hi guys,
i'll tell you my workarround: i'll do it with qtchange from
"VideoToolShed.com" which uses creation-date/time as timecode. Yeah!
The very friendly guy have also written a lot of other cool stuff.
Have a look!

But one question: can anybody tell me, if the last build for 60d has
up to CBR2x or CBR3x ? I have not updated yet, want to do it, cause of
an other feature, but i'm not sure if i can go back to 1.0.9 if it's
"only" CBR2x.

Thanks,
Jan

Alex

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Aug 30, 2011, 2:05:36 PM8/30/11
to ml-d...@googlegroups.com
It's only CBR 2x, which is identical with 3x as long as it doesn't
stop recording. It has more risk and no gain in bitrate, since QScale
clamps at -16 (that's why it was removed).

jraiber

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Aug 30, 2011, 3:49:10 PM8/30/11
to Magic Lantern firmware development
Hi Alex,
thanks for your response. with my sandisk extreme card i dit
recordings with a constant bitrate of 110 Mbit/s. and it handled peaks
up to 148Mbit/s without stopping. (all with audio disabled)
This were very complex pictures, trees with waving leaves. And i do
achieve this high bitrates with CBR 2.7x.
And that's more secure than shooting with qscale-16 all the time,
because at the edge the cbr switched to -15 and saved the cam before
stoping recording.
Yes, i can live with cbr2x, (same picture: av.85, peak 98) but if i
have to shoot with higher ISOs it would be nice to go a little bit
further.
(you can see with bare eyes in this situations, the compression makes
the image blurry, to handle the detail)
All that is much better than with audio enabled, where peaks of 75
kill the take.

So thank you, maybe you want to bring it back, maybe not, i'll still
love Magic Lantern!
Cheers,
Jan

Alex

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Aug 30, 2011, 3:57:31 PM8/30/11
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Wow, so far nobody got past 1.8x (that's why I set it at 2).

I actually have an idea about increasing the buffer size. If it works,
it could go even further. The problem is with the QScale limit at -16
(I wasn't able to remove it).

Tip: you can enter any value in config file (even CBR 10x if you like).

jraiber

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Aug 30, 2011, 4:18:48 PM8/30/11
to Magic Lantern firmware development
"even CBR 10x if you like"

YYYYYYEEEEAAAAAAHHHH!
=)

Jolly Roger

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Sep 1, 2011, 11:37:51 AM9/1/11
to Magic Lantern firmware development
Just a question:

could be useful in some ways to implement a delay between REC-button-
pressed and videorec-start? Maybe a sort of visual countdown like a
chronometer?

(At least, this could save some seconds of useless video when using
the camera on a crane without remote).



On 25 Ago, 18:42, lightimages <twosund...@yahoo.com> wrote:
> Hi Alex
>
> Another simple fix for cam/ext audio sync mark.
>
> Start camera.  Start audio recorder.
>
> Hold an external flash unit, pointed up, near the mic for the recorder
> and press the test button on the flash. Dumping the flash capacitor
> makes a very audible pop that's easy to pickup on a nearby mic.
>
> White frame of video matches POP on mic recorder +/- a frame.  The
> frame offset will be constant if the flash is always the same distance
> from the audio recorder.
>
> I use this trick to sync video cameras and HDSLR's on multi-cam
> shoots. It really helps in spots wherePluralEyesgets lost.

jraiber

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Sep 2, 2011, 1:08:22 AM9/2/11
to Magic Lantern firmware development
Hi Jolly,
i don't know, if it's possible, cause i'm not a programer, but i've a
infrared remote which is one or two bucks on ebay and does an
excellent job.
Maybe you'll try this.
greets,
Jan

jraiber

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Sep 2, 2011, 1:14:27 AM9/2/11
to Magic Lantern firmware development
"I actually have an idea about increasing the buffer size. If it
works,
it could go even further. The problem is with the QScale limit at -16
"

Yes you're right, i shoot last days and the goal of disabling audio
and getting much higher bitrates i reached only in few moments, with
landscape f.e.
Most of the time, while dialog with blurry background, datarate hang
at 50 to 60, even with cbr3x.
So i'm locking forward to a possibility of going beyond -16.

Thanks and greets,
Jan

Jolly Roger

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Sep 2, 2011, 3:53:37 AM9/2/11
to Magic Lantern firmware development
Hi Jan,

it works also from behind?
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