Audio Silence

[Skieth]

okay i was trying to repair this set of audio and zoomed in to see if there was something i was missing and i found this

this is a screen shot of it

Audacity.png (121.01 KiB) Viewed 877 times

now it when played normally it causes a kind of skipping effect what if anything would fix it?

[kozikowski]

I don't know that the picture tells us a whole lot. Because of the way Audacity manages waveforms, a lot of normal recordings look like that.

Can you describe what you were recording and how?

USB turntable, by any chance?

Koz

[Skieth]

what it was a show at an anime convention i was at the strange thing is it acts like silences and with some audio causes a skipping effect i tried normailize equalization and other thing i zoomed in and found that the areas that were silences while others werent affected at all also i forgot to mention i removed the audio from the video with super so its techially list as an MPG in the title but its actually a WAV file also the how was with my Vivtar 4100 digital camera

[Skieth]

okay i'll explain the flat parts are silenced the thing is i never used any silence generating effects and when look at normally

audacity normal.png (130.36 KiB) Viewed 809 times

hence why i zoomed in to see what was up an found flat lines i also played the file while zoomed in to confrim when it went over the flat parts (i even did loop playback) were silent how do i fix this and what could of caused it?

[kozikowski]

<<<Vivtar 4100 digital camera>>>
<<<its techially list as an MPG in the title but its actually a WAV file>>>

I don't believe you.

Unfortunately in Windows, it's a little rough to prove that one way or the other, but if it was a conventional Windows WAV file, it would be playing.

Audacity is a very simple audio program and it depends on its files and environment to be simple, too. A Windows WAV file wrapped in an MPEG data coating isn't going to do it. I can tell you that Video Standard WAV files (48000, 16-bit) play just fine and I do all my production in that format because of the extra fidelity and I slide in and out of video a lot.

One of Audacity's shortcomings is that it will open and try to play and manage certain foreign audio files even though it has no real idea how to do that.


But given all that, full or badly fragmented hard drives will cause Audacity to miss here and there and it will sometimes record a damaged show. When was the last time you defragmented?

Koz

[Skieth]

okay first off i used SUPER to remove the audio and make it wav second it does this in both the orginal video and the audio

Wav.png (22.05 KiB) Viewed 810 times

so its not just audacity making a guess and getting it wrong hence why i came here to try and get help to try and solve the problem

[steve]

I've re-read this topic several times, and I'm still unsure of what you are asking.

1) You recorded something on your Vivtar 4100 digital camera.
2) You converted it to WAV format using SUPER.
3) You open the WAV file in Audacity and find that there are silences in the recording where there should be sound.

A couple of questions:
1) does the original MP3 recorded on the digital camera play correctly? (without the silences).
2) There are lots of variations of WAV format - If you look at the file properties and go to the "Summary" tab, then click on "Advanced" it should say something like "Microsoft PCM 2 channel stereo 16 bit 44100Hz". Can you tell us what it says (or post a screen shot).

[Skieth]

A couple of questions:
1) does the original MP3 recorded on the digital camera play correctly? (without the silences
2) There are lots of variations of WAV format - If you look at the file properties and go to the "Summary" tab, then click on "Advanced" it should say something like "Microsoft PCM 2 channel stereo 16 bit 44100Hz". Can you tell us what it says (or post a screen shot).

1)no it plays the silence in both the oringal MP3 and in the wav file
2)

Untitled.png (10.65 KiB) Viewed 780 times

sorry for any confusion i've caused

[steve]

1)no it plays the silence in both the oringal MP3 and in the wav file

I think we have the answer right there.

Since the original mp3 has the problem, then that's where the problem lies - in the original recording.

The probable cause of it:
The camera is very much a budget device, so the manufacturers have probably cut a few corners to keep the price down. It is recording onto an SD Flash memory card - this type of memory is not particularly fast, although some brands perform much better than others. A common problem encountered with cheaper SD cards is that they can not store data fast enough to catch all the data.
Using a faster SD card may fix the problem (I use a Sandisk card in my portable recorder, and it works great), or if the camera has the option to reduce the quality, then less data needs to be stored which may then work without the audio drop-outs (though at lower quality).