-
Sound problems after conversion to mpe2
After converting my timeline from 23.98 to mpeg2 29.97 using compressor (15bps), I noticed some skips in the sound during bars and tone. Is it possible that my PowerPC dual 2.0 is just two slow to keep up? The 30 minute show itself seemed fine, but I am concerned. The timeline is smooth and there were no reports of errors from Compressor. Please advise.
jmf
-
9 Replies
-
Does it play with the same issues on other computers? Also did you use an audio codec to compress the sound or is it PCM?
Tone can be a demanding signal for data compression as it is a pure sine wave so if you compressed the audio it might only be tone that glitches.
-
What kind of file are you making if it’s 15mbps? If it’s for SD DVD, that’s too much bandwidth. If it’s for some other purposes such as a digital delivery, then I’ll shut up.
-
It plays fine in the timeline, but the same problem is experienced by all computers after conversion. My concern is my computer not having enough horsepower during conversion. Is there a way to make an mpeg2 file without compression the sound. The project is a standard definition TV show. (see conversion details below)
jmf
Name: Program Stream
Description: MPEG-2 Program Stream with MPEG audio at 48 kHz. Settings based off the source resolution and frame-rate.
File Extension: mpeg
Estimated file size: 3.24 GB
Type: MPEG-2 program stream
Video Encoder
Format: M2V
Width: 720
Height: 480
Pixel aspect ratio: NTSC CCIR 601/DV
Crop: None
Padding: None
Frame rate: 29.97
Frame Controls: Automatically selected: Off
Start timecode: 00:00:00:00
Aspect ratio: 4:3
Field dominance: Progressive
Average data rate: 15 (Mbps)
2 Pass VBR enabled
Maximum data rate: 20 (Mbps)
High quality
Best motion estimation
Closed GOP Size: 15, Structure: IBBP
Audio Encoder
Format: MPEG
Sample Rate: 48.000kHz
Channels: 2
Bits Per Sample: 16 -
[jack fox] “It plays fine in the timeline, but the same problem is experienced by all computers after conversion”
How are you playing the MPEG-2 in the computers?
With QT Player?
This is not the best application to try an MPEG.
Try opening the file with MPEGStreamclip or bring it to DVDSTP and see(?) how it sounds.
Those application are more fitted to play MPEG-2 than QT Player.
Rafael -
Tried streamclip, same problem.
jmf
-
I would expect lack of grunt in your computer to simply make the encode longer. Encoding audio isn’t hard.
mpeg audio isn’t too bad, (in fact I prefer it to AC3). Do you get any settings for the audio compression like variable bit rate, maximum bit rate etc? If so then can you try a higher maximum and choose VBR and see if that helps.
-
Okay, I changed the maximum bit rate (20 to 32), and that helped. Now I have a few skips in the first couples seconds, during the bars and tone, and that’s it. Thanks. Why I’m having any problem with the audio is still a mystery.
jmf
-
Have you checked the export? Is it good?
-
other suggestion:
If the picture is OK, you can make the mp2 audio in ffmpgx (where you can set the data rate up to you) and mux it with the same application.
Rafael
Reply to this Discussion! Login or Sign Up