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Sync Ignores Quality Settings


Ceth
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I'm using folder sync with 3.0.5724.6.  It doesn't matter what profile or quality setting I choose, I get the same size of file with the same apparent quality (which is poor).  For example, when I start with large file (1.4 GB), and convert to low quality baseline, or high quality general, I get two files of identical size (307MB)  down to the last byte.  I've tried this with three different files and the results are the same.

 

These are the ffmpeg commands from the logs:

ffmpeg.exe -fflags +genpts -i file:"inputfile" -map 0:0 -map 0:1 -map -0:s 
-codec:v:0 libx264 -vf "scale=min(iw\,1280):trunc(ow/dar/2)*2" -pix_fmt yuv420p 
-preset superfast -crf 28 -maxrate 1372000 -bufsize 2744000 -vsync vfr 
-profile:v high -level 40 -map_metadata -1 -threads 1 -codec:a:0 aac -strict 
experimental -ac 2 -ab 128000 -af "aresample=48000:async=1,volume=2" -y 
"outputfile"
 
ffmpeg.exe -fflags +genpts -i file:"inputfile" -map 0:0 -map 0:1 -map -0:s 
-codec:v:0 libx264 -vf "scale=min(iw\,1280):trunc(ow/dar/2)*2" -pix_fmt yuv420p 
-preset superfast -crf 28 -maxrate 1588423 -bufsize 3176846 -vsync vfr 
-profile:v high -level 40 -map_metadata -1 -threads 1 -codec:a:0 aac -strict 
experimental -ac 2 -ab 128000 -af "aresample=48000:async=1,volume=2" -y 
"outputfile"

The only differences between the two is the -maxrate and -bufsize options.  Again, one is baseline low quality, and the other is general high quality.

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So just looking the command line, everything looks good here. when you drop down in quality we reduce the bitrate requested from ffmpeg. but why it's producing two identical videos, i'm not sure. in fact i would guess that that's not happening and perhaps your method of determining that might not be correct. but it is just a guess. you could try running those command lines with ffmpeg in a standalone fashion.

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I double checked and according to the command line, the files differ by about 900 bytes (not sure if that is actual difference or "used by disk" difference).  Shouldn't the difference be larger?  And shouldn't choosing a different profile change the encoding settings?

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