[FFmpeg-user] Apple Lossless conversion requires resampling?

Carl Eugen Hoyos cehoyos at ag.or.at
Mon Jun 9 16:45:42 CEST 2014

Marcus Johnson <bumblebritches57 <at> gmail.com> writes:

> why does it depend on aresample? 

(Command line and complete, uncut console output 

> does this mean that the output isn't lossless

Please test: If it is not lossless, this would be a 
serious bug that we would like to know of!
(for 16 bit!)

> or at the very least that it's wasting CPU time 
> resampling audio each time I convert it?

It is "wasting" CPU cycles to speed the general 
transcoding process up.
(Or more exactly: To speed up processes in general, 
possibly - but unlikely - at the cost of some 
specific transcodings being slower.)

> ./configure --enable-shared 

> --enable-lto

I am assuming you are using this flag (that is extremely 
expensive at compile time) because you want a faster 
executable, is this correct?

> --disable-yasm

This option makes sure your final executable is slow.

> --enable-opencl --disable-filters

These options are useless together
(I am not sure --enable-opencl is very useful over 
all but in any case, it only works with some 
selected filters.)

> --disable-bsfs --disable-decoders --disable-demuxers 
> --disable-encoders --disable-filters --disable-hwaccels 
> --disable-indevs --disable-muxers
> --disable-parsers --disable-protocols

There is --disable-everything (which does not disable 
everything but exactly the same as these options).

Carl Eugen

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