Fast audio in Handbrake HAVC-Intra (MXF) to H264

SecondWind-SK wrote on 5/18/2015, 8:08 AM

I've rendered a 1920x 1080, PCM audio timeline to Sony XAVC HD 1920x 1080 Intra 29.97P. The resulting file looks and plays great. When I use Handbrake to encode an H264 file, the video looks great but the audio plays sped up. a 3:10 original to a 1:57 running time in the MP4. In Handbrake, on the audio tab, the original audio stream is identified as "unknown PCM":. Anybody know what's going on?

Comments

rraud wrote on 5/18/2015, 9:06 AM

Don't know what the HB problem is, but after the fact, an AAC audio file could muxed in fairly easily. I do this all the time when I decide re-mix a project.

NormanPCN wrote on 5/18/2015, 9:49 AM

MXF audio is normally has each audio channel in a separate audio stream. Two streams for stereo. Handbrake cannot handle these separated audio streams.

SecondWind-SK wrote on 5/18/2015, 10:02 AM

Thanks Norman. Probably the problem. What is a better digital intermediate to use so that I can take advantage of Handbrakes H.264 encode?

OldSmoke wrote on 5/18/2015, 10:54 AM

XAVC-S works fine and the losses over XAVC-Intra are minimal on the final output from HB.

SecondWind-SK wrote on 5/18/2015, 11:12 AM

Thanks. I'll try that.

NormanPCN wrote on 5/18/2015, 4:14 PM

If you really NEED to feed an MXF with separated stereo audio to Handbrake then you can use the following ffmpeg command line to do so.

ffmpeg.exe -i %1 -c:v copy -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le "%~dpn1.mov"

It simply copies the video stream and merges the separate streams into a single unified stereo stream.