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View Full Version : Handbrake generates output with different settings


bjoker
9th May 2013, 23:32
Hello friends,

I'm using handbrake 0.9.8 to convert my DVDs into MP4. But I find output file with different settings than what I used. For e.g, I used the settings shown below:


http://i47.fastpic.ru/big/2013/0510/c7/678b11948c2f21f845436077f55f24c7.jpg


and MediaInfo shows:

Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 23.974 fps
Maximum frame rate : 23.981 fps


Bit rate : 64.0 Kbps
Maximum bit rate : 120 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 32.0 KHz



handbrake log excerpt:

CLI Query: -i "F:\DVDs\VIDEO_TS" -t 1 -c 1-9 -o "C:\Users\admin\Documents\HandBrake\test.mp4" -f mp4 --strict-anamorphic -e x264 -b 640 -2 -r 23.976 --cfr -a 1 -E ffaac -B 32 -6 stereo -R Auto -D 0 --gain=0 --audio-copy-mask none --audio-fallback ffac3 --markers="C:\Users\admin\AppData\Local\Temp\test-chapters.csv" -x ref=1:weightp=1:subq=2:rc-lookahead=10:trellis=0:8x8dct=0 --verbose=1
User Query: False


Is it a bug with Handbrake or am I doing something wrong. I wanted to set it "constant framerate" and audio bitrate of 32kbps.

Appreciate any help. Thanks!!

JohnAStebbins
11th May 2013, 18:11
mediainfo doesn't do a very good job of identifying variable vs. constant framerate.

The timebase used by HandBrake is 1/90000 (that is 90000 ticks per second). At a framerate of 23.976 that works out to about 3753.75 ticks per frame. So most frames will get 3754 (90000/3754 = 23.974 fps) ticks and some will get 3753 (90000/3753 = 23.981 fps) ticks. mediainfo calls this "variable", but by the definitions normally used for video streams, this is not variable. 1/90000 is the same timebase that is defined in the mpeg2 spec and is used by all mpeg2 compliant streams.

The audio bitrate issue is a bug in the UI. faac does not support 32kpbs stereo encoding (minimum is 64kbps for stereo). The underlying library sanitized the value rather than failing to encode.