Snapping captured & transmitted audio

We're trying to make a screen grabber / voice chat application with JMF. Basically, it's just a bunch of modified example classes found on the sun netsite, but it doesn't seem to work perfectly, yet. The problem is that when transmitting only audio or video, it works fine, but when we transmit both, the audio has an annoying snapping sound with it, it becomes almost unrecognizable.
The video is set to JPEG_RTP format and audio to DVI_RTP at 8000 bps sample rate, 4 bits sample size, mono. It doesn't seem to help if we lower the quality of the video or raise the quality of the audio.
Could anyone give us so much as a hint of what the problem could be all about? I think something goes wrong in the transmission, but how to fix it?
Thanks for the help :)

Did you figure out the snapping in your sound.
I'm just doing a small app that plays a short sound and it really SNAPS when the sound starts.
My Best,
Gordon

Similar Messages

Unable to capture 2 audio tracks

FCP refuses to capture 2 audio channels?! I have one mic on channel 1 and another mic on channel 2 but FCP captures only 1 mono track eventhough in Clip Setting both channel 1 and 2 are selected. Does anybody know what could be wrong?
Another thing is that when I have captured a clip - it won´t appear automatically in the Browser as it always has done? Now I need to import the Clip from my Project folder. FCP going crazy.

Hi boxpuppy,
iTunes is not able to import some Windows Media Player files. See this article for further information -
Importing Windows Media Audio files with iTunes for Windows
http://support.apple.com/kb/HT1844
Thanks for using Apple Support Communities.
Best,
Brett L

Captivate 7 is not capturing system audio, and the software has a broken link

The Problem:
Captivate 7 is not capturing system audio. When I start a screen recording, the line with "System Audio" and its checkbox are eternally grayed out. Next to the grayed out words is a link that says, "Why is this disabled?"
The lnik goes to: http://www.adobe.com/go/cpaudio
Which is not a valid link, so Adobe's site redirects me to blogs.adoble.com/captivate which is ZERO help. Both browsing and the search bar bring no answers.
The Device:
Apple Macbook Air, Mid 2013, running OSX 10.9.2.
What I've done already:
Obvsiously I have set Captivate 7's preferences to capture system audio, and have set System Settings -> Security and Privacy -> Privacy -> Accessibility to allow Captivate to control my computer.
I have also tried clicking the Mic icon, Selecting Source with the System Audio icon and that doesn't record system audio either. It acts like it is recording system audio, but when I stop recording I get a popup that says, "Cannot record system audio. Ensure that you are playing audio on your computer [Okay]"

It's a wierd one.
One thing to try, and this fixes a lot of things, trash your preferences.
http://www.digitalrebellion.com/prefman/
DM

Why Does FCE capture DV audio as dual mono instead of stereo?

FCE captures DV audio as dual mono audio files instead of a single stereo audio file. You can see this if you "Show Movie Properties" in Quicktime. Files I captured in Premiere 6 years ago have a single stereo file. The problem is that the new dual mono format for DV won't play on the Final Cut Pro 3.04 installed on my wife's G4 (OS 10.4.11, Quicktime 7.6.2). FCP 3.04 doesn't see any audio for these dual mono files though it will play the video. It won't even create an audio waveform. But FCP 3.04 plays the older stereo audio clips captured in Premiere just fine. And if I export the dual mono files out of QT as a stereo file, then FCP 3.04 will play them just fine.
This lack of backward compatibility is quite frustrating. I can't seem to find a setting in FCE that will capture audio as a single stereo file. Why isn't NTSC DV always stereo? I guess maybe they had to go dual mono to facilitate surround sound panning in 5:1 or something. If nobody knows how to do this in FCE, I guess I'll just capture in FCP 3.04. I spent the better part of a day figuring out this hidden little tidbit. The lesson is don't try to go back!! We must always accelerate forward into newer versions and formats.

The problem is in your wife's machine. She is using a version of the OS and QuickTime that are much too new for the version of the software she's using. She really not not be using an OS newer than 10.4.10 and QT should 7.2 or earlier.
Yes. I was beginning to suspect that this was at the root cause of my issue. Thanks for the info. Frankly, my wife needs to buy a new Intel iMac so we'll both be able to work on the video I'm dumping. I had FCP 3 lying around from years ago and it's the only thing that might have worked on her old G4 AGP, so I thought I'd give it a try.

And suddenly my captures are audio-less...

I have been digitizing some VHS tapes through an ADVC100 this evening. I've done about 15 tapes without trouble, then suddenly FCE stopped capturing the audio from the tapes. This happened without me quitting FCE or anything. Just stopped. I tried to capture with iMovie and iMovie captured the audio fine but iMovie's capture is quite clunky for my tastes. I trashed FCE's prefs tried different setups. Restarted and still cannot get back to FCE's capturing goodness that I had for the previous 15 tapes. grrrrrrrrr
Idears????

I don't know whether this applies to your situation but occasionally FCE can give the impression that the audio has not been captured when it actually has.
Go to View>Video Out and check that "Canvas Playback" has been selected.

Problem capturing Stereo audio

I know I have 2 separate tracks of audio on my tapes. One wireless mic and one shotgun mic. I have tried all audio capture settings, but FCP just keeps on capturing the first audio channel? Any suggestions how to get both audio tracks captured.
I even tried to capture with tapes that I´ve succesfully managed to capture both audio channels before. I just added a second scratch disk, also internal, could this have to do with my problem?

When I open the Log & capture window there are items missing in the Capture Settings and Clip Settings Tab?! I can´t for intsance choose how many audio cahnnels I want to capture. Anybody seen thing like this?

Trouble capturing just audio from beta tapes

Hello, I am trying to capture some audio-only beta tapes and having trouble. The deck is all hooked up correctly (deck to IO box to mac), and I followed the manual instructions on how to create an audio only capture setting. When I go to capture the audio, I can hear the audio playing and it says "now capturing", but when it stops I get an error saying "Final cut was unable to read the movie file just captured." Is anyone familiar with this kind of problem? Let me know if you need anymore information about my settings (unfortunately I am relatively new to final cut).
Thanks,
Mike

Try this (no guarantees but it used to work): Go into your scratch disk settings and enable "capture video and audio to separate files." Wasn't consistently a problem, but when it was, this solved it. But I used to get the error when tried to initiate the audio only capture. Be sure and turn this off before you capture video and audio.
Also, what happens if you try and capture video and audio of the same section? You can always just export the audio and then delete the capture.

Capturing 4 Audio Channels - HDV???

Correct me if I'm wrong, but it is NOT possible to capture 4 audio channels all at once in FCP?
If this is this case, how do you go back and capture in another pass? Right now I can only capture the two channels that go along with the onboard mic, and not the channels that go with the XLR audio (in this case a Lav Mic.)
I've tried to create a new capture preset, but it doesn't seem to work w/HDV.
Should I try capturing the audio in a second pass using standard def? Would that work?
Any thoughts would greattttttttttttly be appreciated.
Thanks!

As Thomas suggested in that thread, "Capturing Multiple Audio Channels", in chapter 20 of the the FCP User Manual is a great resource. But I'll break it down for you anyways...
Here's how I capture 4-tracks of audio via Firewire with Final Cut Pro:
Go to -
Final Cut Pro Menu/Audio/Video Settings.../Capture Presets Tab
Create two capture presets (1 set for the first two channels, the 2nd set for the last two channels and maybe one for all 4 channels mixed if you'd like)
Select a Capture Preset and choose Edit then set which channels you'd like the preset to capture inside the Quicktime Audio Settings section of the Capture Preset Editor window. Make sure your device is plugged in and turned on or else the option will be greyed-out.
Open the Log and Capture window in the Capture Settings tab and select which Capture Preset you'd like to use depending of which audio channels you'd like to capture.
To make sure you're caturing 4-channels on your camera:
Go To-
Menu/Audio Setup/Audio Mode/ 12bit 1/2 , 3/4
Throw the phones on and monitor the channels using the Audio Monitor button on the side of the camera. You can switch between monitoring the first 2, the second two, or all four channels at once. Remember if the camera is set to record 4 channels then it'll record 4 channels no matter what channels you're monitoring.

Capturing both AUDIO and VIDEo at a time.....

Hi Every One,
I was able to capture audio separately and save in a file and video separately and save in a file...
I want to Capture both audio and video at a time and save in a file is it possible, if possible suggest me the way

Merging Tracks from Multiple Inputs
[http://java.sun.com/javase/technologies/desktop/media/jmf/2.1.1/solutions/Merge.html]

Capturing streaming audio on Macbook Air?

I want to capture streaming audio from a website on my MacBook Air. But is this possible when the MBA lacks an external microphone? How do I go about it? The sound quality needs to be decent. My compture is brand new and has OS X10.9.1 if that's relevant. Many thanks!

There are tons of such audio (and video) capture apps on the APP STORE, such as twisted wave, sound studio, Amadeus,etc etc
more professional and pricey APPS such as Adobe tools, screen flow, capture screen.
most of the cheap ones can be had for $5 or so.
Why do you need a Mic? audio can be captured internally. Your Air does have an onboard external mic on the left side, either 2 holes, or older Air one larger multi-hole mic input.
for web audio however you want to use an application.

How to use Audacity to capture streaming audio

Hi all-
I have Audacity and am trying to figure out how to capture streaming audio from an internet radio station. Have heard this is possible, but as yet have not been able to figure out how to do it. Any ideas?
DK

Hello,
but when I created a package and added OdiWaitForLogData, pb began. the step that has OdiWaitForLogData succeed. but my interface failed. the step "Load Data" failed.why?
There is no reason for that. WaitForXXX does not affect the data stored in the CDC infrastructure, but just detects it.
- What type of CDC are you using: simple or consistent set?
- Did your interface used journal data only?
- What error did you get precisely on the "Load Data" task?
Could you tell me how to schedule a package?For scheduling, I think you should have a look at "Generating a Scenario" in the user manual. under the generated scenario node, you'll see the schedule node and you can start scheduling from here.
Regards,
-FX

I need to capture streaming audio and save to a wav file

I need to be able to capture an audio stream delivered via ethernet using UDP protocol and then save to a wav file.
I currently can capture the data stream but do not know how to format the data to save it to a file. Our format is 16KS/s, 16bit, PCM, no compression.

Did you do the thing about searching in the example database. Let us use that as base for discussion. Those who put in some effort will be rewarded. Also check out the AU file format http://en.wikipedia.org/wiki/Au_file_format As it is big-endian http://en.wikipedia.org/wiki/Big-endian the numbers can be stored as is in Labview. Must players,matlab, etc can use the AU file format.
Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)

How to Capture Streaming Audio

I'm looking for a technique or app for capturing streaming audio from my 3GS. Any ideas?

Check the app store as I know there are apps that will stream and capture audio. Basically, the app that is doing the streaming has to do the capturing as well. Otherwise, any recording app running in the foreground mutes the audio from any backgrounded app.

Capturing DVD audio into sound files to be played in iTunes

Hi. I am new to the land of Apple. I got an iBook G4 with a Superdrive and I have a question; well, more than one, but I will just ask one for now.
I have several purchased DVDs and I want to capture the audio from these and save them into a format that can be captured into iTunes.
I have downloaded Audicity and tried to use it to capture the audio while I am watching the DVD. No luck!
How can I accomplish this task?
Thanks,

Welcome to the Discussions. Please read the message you missed at the top of the page about this particular Discussion:
Forum: Feedback about New Discussions
Please Read This Before Posting Here
This Feedback about New Discussions forum is intended for questions about how to use Apple Discussions and for general constructive feedback about how the Discussions system is operating or how it may be improved. Please use this forum appropriately. Failure to do so may result in your posting privileges to this forum being disabled.
If your question concerns a hardware or software technical issue, please do not post in this forum — instead, go to the Apple Discussions Homepage, select an appropriate product category and follow the links until you reach the correct forum for your post, then click the Post New Topic link.

What application for capturing Video+Audio?

Hey,
I've recently installed (with great success) the WinFast 2000 XP RM video capturing card (according the instructions in the wiki).
I can now watch TV using TVTIME or KDETV.
Question is, how can I capture video + audio, to a .avi file?
Note that the card doesn't have an audio input, and that the audio input is connected
to the line-in of my onboard sound card.
I got some instructions from this page: http://forum.videohelp.com/topic307679.html
But, when trying to issue:
mencoder -tv norm=PAL:driver=v4l2:width=720:height=576:input=2:fps=25 tv:// -oac lavc -ovc lavc -of mpeg -mpegopts format=dvd -vf pp=lb/ha/va/dr,hqdn3d,harddup -srate 48000 -af lavcresample=48000 -lavcopts vcodec=mpeg2video:vrc_buf_size=1500:vrc_maxrate=8000:vbitrate=7000:keyint=15:acodec=mp2:abitrate=192:aspect=4/3 -o capture.mpg
I didn't get any sound at all (though the video capturing worked perfectly).
Any help would be appreciated,
Thanks
fiod
Last edited by fiod (2008-05-18 16:06:32)

Ok. The transcode command line is no fun and transcode doesn't work with alsa, so you'll need to have alsa-oss installed. I use v4lctl (part of the xawtv package) to set the video card input and I capture to mjpeg rather than mpeg2, because it's better for editing, with ac3 audio, like this:
#!/bin/bash
# Generate recording filename
if [ -z "$1" ]; then
TMPFILE="tmp-`date +%F-%X`-mjpeg.avi"
else
TMPFILE=$1
fi
# Set capture card
v4lctl -c /dev/video2 setinput Composite1
transcode \
-u 256,2 \
-x v4l2=resync_margin=1:resync_interval=250:overrun_guard=1,v4l2 \
-g 720x576 \
--import_asr 2 \
-i /dev/video2 \
-H 0 \
-p /dev/dsp1 \
-e 32000,16,2 \
-E 48000,16,2 \
-n 0x1 \
-N 0x2000 \
-b 192\
-J resample,smartyuv,mask=lefttop=0x6:rightbot=720x564,hqdn3d=luma=4:chroma=3:luma_strength=6:chroma_strength=4,pv=cache=30 \
-y ffmpeg \
-F mjpeg \
-o $TMPFILE
exit 0
(The "-J mask=lefttop=0x6:rightbot=720x564" hides some vhs artefacts.)
Of course, my card is different to yours, so you'll need to adjust the audio device (/dev/dsp?) and video device (/dev/video?). Use "v4lctl -c /dev/video? list" to get the possible options for your card, like this:
[david@darkstar ~]$ v4lctl -c /dev/video2 list
attribute | type | current | default | comment
-----------+--------+---------+---------+-------------------------------------
norm | choice | PAL-DK | PAL | PAL PAL-BG PAL-I PAL-DK NTSC SECAM SECAM-DK SECAM-L SECAM-Lc PAL-M PAL-Nc PAL-60
input | choice | Televis | Televis | Television Composite1 Composite2 S-Video
audio mode | choice | mono | mono | mono stereo lang1 lang2
bright | int | 128 | 128 | range is 0 => 255
contrast | int | 68 | 68 | range is 0 => 127
color | int | 64 | 64 | range is 0 => 127
hue | int | 0 | 0 | range is -128 => 127
volume | int | 15 | 0 | range is -15 => 15
mute | bool | on | off |
Mirror | bool | off | off |
Invert | bool | off | off |
y offset o | int | 0 | 0 | range is 0 => 128
y offset e | int | 0 | 0 | range is 0 => 128
automute | bool | on | on |
Oh, and my ~/.transcode/ffmpeg.conf contains:
[mjpeg]
precmp = 2
cmp = 2
subcmp = 2
mbd = 2
dia = -2
predia = -2
Last edited by azleifel (2008-05-18 20:37:31)

Snapping captured & transmitted audio

Similar Messages

Maybe you are looking for