Converting Downloaded FLV Recording to MP4 using FFMPEG

[mr98978428]

We have been creating MP4s of our downloaded webinar FLVs from AdobeConnect but since February, we have been unable to generate good MP4 files.  The audio/video are not synced properly.

The FFMPEG log shows thousands of "DTS - Invalid timestamp" errors indicating the FLV files being generated are not quite the same as they were a few months ago.

Can anyone share the FFMPEG command you use to convert your AdobeConnect videos to MP4?

Thank you.

[forresttw97892848]

I am having similar issues, our mp4 files have serious audio sync issues. The audio sync 'drifts' - in a 1 hour video the audio can be off by up to 15 seconds of more, and around 30 minutes it syncs up correctly.

I have tried Handbrake, multiple different settings, same results.

I have tried Adobe Media Encoder, multiple different settings, same results.

I must be missing something, I cannot find the optimal settings for converting flv to mp4 anywhere online to prevent this issue.

[forresttw97892848]

I did find this just now, I'm going to try using these settings:

http://blogs.adobe.com/connectsupport/the-specifications-for-mp4-conversion/

[forresttw97892848 · Accepted solution]

Okay, nevermind, I got on the Adobe Connect Support Chat and they provided these settings to use:

Format – H.264

Dimensions – 880x586 [you may alter this if required]

TV Standards – NTSC or PAL

Frame Rate – 29.97fps

Pixel Aspect Ratio – Square Pixels

Bitrate Encoding ~ 500kbps [0.5Mbps]

Audio Aspects:

Format – AAC/MP3

Bit Rate – 128 kbps

Frequency ~ 48 kHz

Channel – Stereo

Encoding – 2 Pass Encode for better quality

I put that into Handbrake and it worked like a charm, no more audio sync issues.

I hope that helps