[FFmpeg-devel] [PATCH]Use flt as default input format for libaacplus

Sergiy piratfm at gmail.com
Fri Nov 25 17:40:39 CET 2011

2011/11/25 Carl Eugen Hoyos <cehoyos at ag.or.at>

> Hi!
> If I understand aacplusenc.c correctly, float is the native format for the
> encoder:

Yes, You are right, But when I digging in aac+ code I found, that  to make
sound with normal loudness each sample must be multiplied with SHRT_MAX.
This needs more test, due I have cuccess with wav files only with -1.0 ...
+1.0 floats.

As you see in that code, the floats, that given to 3gpp code are -32768.0
... +32768.0:

>        case AACPLUS_INPUT_FLOAT: {
>            float *inbuff = (float *) inputBuffer;
>            for (i=0; i<samplesInput; i++)
>                aacp->inBuf[...] = inbuff[i] * SHRT_MAX;
>            break;
>        }

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