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FFMPEG terrible conversion quality when using -sameq (same quantizer as source) flag

Tags:

video

ffmpeg

I'm trying to convert .flv videos to .ogg format. After experimenting for a while, the ogg is always produced as very low quality. Even when I use the -sameq flag which uses the same quantizer as the input file, the quality is substantially worse.

Since I am pretty new with ffmpeg, does anyone know some good options to convert video files with maximum quality?

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Brad Avatar asked Apr 09 '11 08:04

Brad


1 Answers

As far as I remember -sameq can mimic the quality to a certain level with the limitation of buffsize. Means either you need put some extra settings in use which I think mostly concerns -buffsize, buffer related settings etc.. (But i may be wrong i'm not using ffmpeg for a year.)

Or use the qscale tag if you need the best, but i need to warn you the size of the output will 3 or 4 times bigger differentiating on video. Usage is -qscale [x] where [x] (without brackets) is the quality value of output, lower is better. If you put -qscale 0 it means the best. Also you may want to use -ar (audio frequency) and -ab (audio bitrate: 192k is enough for HD, 128k is the most common) for better audio quality.

Example usage of -qscale -ar -ab tags:

-i a1.wmv -qscale 0 -ar 44100 -ab 128k -y aOut.wmv
like image 145
umutto Avatar answered Sep 16 '22 13:09

umutto