Need Help Re: Bit Rate vs. Audio Sample Rate etc.

jerancampy22 wrote on 7/7/2016, 6:19 AM

Hello all-

I am using "Movie Edit Pro 2016 Plus" which works very well for a majority of applications and projects I use it for. Usually I am bringing in different videos and images and then I do an audio narration and after I export to a mp4 file I never have any issues. Yes, the render time is longer than I would hope but I am happy with the outcome and so I don't mind the long render times. I am however having issues with one particular project that unfortunately I need to do weekly and cannot figure out what I am doing wrong. So, that details are below.

CPU: AMD FX-8320E 8 Core Processor 3.20 Ghz

16.0 GB RAM 64 Bit

Windows 8.1

Directx Runtime Version 11.0

GPU: GE Force GTX 950

So, weekly I do a 3 hour podcast and when completed, I can download the show which downloads as a stand alone file 64 kbps and usually between 75-80 mb. So, now I have on my computer the 75mb file in mp3 mode and consisting of all audio. I now want to upload this file to YouTube but obviously it needs to be in video format so to make it simple, I will just go throught 10 or so images that just repeat for the 3 hours.

Now, if I open the audio file and listen... it sounds great, No pops no problem. However, as soon as I drag this file into Magix, it begins to play with pops in the audio. Sounds terrible and in fact, it is not worth even listeing to. It sounds terrible. I checked the audio settings because I assume this is in some way because of or as a result of the original file being 64 kbps. But I see nothing like that, I see Audio Sample Rate and mine is set to the highest which is 48000 hz.

I also see Audio Buffer settigns which are as noted below...

Buffer # 4

Multi-Track Size: 16384

Preview Size: 4096

So, my question is simply... what am I doing wrong here. If I need to change the settings, please tell me which ones. As I said, the settings "as they are" are perfect for my video creations but those are usually 10-45 minutes and never have sound issues at all. But I cannot get my podcast to come out clean. The option of downloading the show at a different kbps is not possible, but I can always convert it but have no clue what I am converting it to or why. Please someone with some sort of technical mind, please help me so that I can start loading my podcast on to YouTube without the hassle. Anyone have any feedback as to why I hear constant pops and snaps in my audio once sent to Magix. This happens even before I add any images to the project. And after I add them all, all I am doing is exporting a mp4 file as I normally do and it comes out so bad I cannot add it to YouTube. Thanks in advance.

Comments

yvon-robert wrote on 7/7/2016, 10:25 AM

Hi,

Check your file using MediaInfo free software the diffrence with the problematic ausio file and the previous working right. Use tthe same parameters. Normallu 44,1 or 48 KHz file sample and 320 Kbps bitrate gives best quality files may be your birate is too low.

Regards,

jerancampy22 wrote on 7/7/2016, 11:50 AM

Wait, a little confused. What bitrate is too low? And what do you mean to check the previous working correct? I can add 50 mp4's into one video and it works fine. I am having issues with the files (everyone of them) that I get that are 64kbps that I try and input into a new video project

yvon-robert wrote on 7/7/2016, 9:51 PM

Hi,

MediaInfo is a small software from SourceForge and we use it to analyse the video file like mp4 file :

Video file is divided in 2 parts : 1) Video track 2) Audio track

In a file like one from my computer :

First video track (Première piste vidéo) see information on captured screen

First audio track (Première piste audio( you can see 192 Kbps this is bitrate that means higher bitrate more quality, after 48,0KHz this is audio sample rate normally 44.1 or 48 is noreml, after 2 channel AAC that is stereo sound.

My idea check a file that work for you and after check the file that cause problem to find the difference between a good and bad.

Regards,

johnebaker wrote on 7/8/2016, 8:29 AM

. . . . Bit Rate vs. Audio Sample Rate . . . .

These are the two of the three main parameters used to describe an audio file the third is Bit Depth, however this is not relevant to the issue you are having, - in laymans language they mean the following:

Bit Rate - this indicates the amount of compression applied to the file, the lower the bitrate the more compression is applied along with some loss of quality.

In your example a 64 kbps can be continuously streamed over an Internet connection that is faster than 64 kbps. The audo is highly compressed comapred to CD quality audio which has a bitrate of - 1411.2 kbps.

Sample rate - this is the number of times per sec the analogue audio signal is sampled for conversion to digital. CD audio is 44100 Hz (samples / second) and determines the quality of the audio the lower the figure the lower the audio quality..

The problems is we do not know what the actual sample rate of the original audio is - this is where you need to analyse the audio file using MediaInfo as YR has posted.

The sample rate has a bearing on the problem because MEP is quite happy with 44100 Hz and 48000 Hz audio, however it can have issues with lower sample rate audio, which I suspect your audio file is.

The symptoms described are typical of low bitrate audio being played in realtime at 48000 Hz bitrate.

There are many audio converters available which will convert a low audio bitrate file to either CD standard ( 44100 Hz ) or 48000 Hz sample rates.

I use MovAvi Video Converter for converting file formats - it also does audio and images as well as video.

HTH

John EB